file which includes the original illustrations4 ,see #dffcd-;h4htm or #dffcd-;h4zip3 7https3_/_/www4gutenberg4org_/cache_/epu b_/#dffcd_/pg#dffcd-;images4html7 or 7https3_/_/www4gutenberg4org_/files_/#df fcd_/dffcd-;h4zip7 ,images of the original pages are available through ,internet ,archive4 ,see https3_/_/archive4org_/details_/lifeofri chardtre#jbtrevrich ,,life ,,of ,,richard ,,trevithick1 ,with an ,account of ,his ,inventions4 by ,,francis ,,trevithick1 ,c4,e4 ,illustrated with ,engravings on ,wood by ,w4 ,j4 ,welch4 ,,volume ,,ii4 ,london3 ,e4 ,f4 ,n4 ,spon1 #dh1 ,charing ,cross4 ,new ,york3 #ddf1 ,broome ,street4 #ahgb4 ,london3 ,printed by ,william ,clowes and ,sons1 ,duke ,street1 ,stamford ,street and ,charing ,cross4 ,,contents ,,of ,,volume ,,ii4 ,,chapter ,,xvii4 ,,various ,,inventions4 ,stone-crushing mill1 #ahjd--,portable puffer1 #ahje--,staffordshire potteries--,engine for ,south ,america--,diversity of steam appliance--,numerous high-pressure engines--,west ,india ,dock locomotive--,engines at ,newcastle--,blacklead lubricator--,engines in ,wales--,mine engines on wheels1 #ahjd--;,engines in ,london--,engines to be sold in market towns--,blast-furnaces--,arated steam-boiler--,st4 ,ives ,breakwater--,dolcoath blast copper furnace--,davies ,gilbert's opinion of the arated steam-boiler--,trevithick's advice to a brewer--,agricultural engines--,west ,india engines--,thrashing engine--,horizontal engines--,expansive steam--,cold surface condenser--,air-pump--,expansive cam--,fire-bars--,comparison with ,watt's engine--,stone-boring engine1 #ahac--,plymouth ,breakwater1 reduction in cost--,locomotive engine1 #ahac--,stone splitting--,new method of stone boring1 #ahac--,screw bit1 #ahac--;,falmouth ,harbour--,exeter ,bridge--,engine at ,lima--,proposed train from ,buenos ,ayres to ,lima--,west ,india portable engine ,page #a-ce ,,chapter ,,xviii4 ,,agricultural ,,engines2 ,,loss ,,of ,,papers4 ,sir ,christopher ,hawkins's thrashing machine1 #ahab--,report of three wise men--,cost of horse and steam power--,wheal ,liberty engine--,sir ,john ,sinclair and the ,board of ,agriculture--,cost of engine--,power of engine--,welsh locomotive--,trevithick on steam agriculture--,west ,indies engine--,horse-power--,trevithick on patents--,engines in charge of labourers--,teapot--,detail of agricultural engine--,lord ,dedunstanville's thrashing machine--,plymouth ,breakwater locomotive--,wheal ,prosper engine--,wheal ,alfred engine--,steam-plough--,cultivation of commons--,combined steam-tormentor1 narrower1 and shoveller--,mr4 ,rendal's thrashing machine--,cost and work performed by thrashing engines--,their durability--,bridgenorth engine--,trevithick's drawings light the tires #cf-fh ,,chapter ,,xix4 ,,pole ,,steam-,,engine4 ,return to ,cornwall1 #ahaj--,wheal ,prosper pole vacuum engine1 #ahaa--;,cylindrical boilers1 #ahaa--,steam pressure1 #ajj lbs4--,duty of engine1 #dj millions--,expansive working1 #ahaa--;,herland high-pressure pole puffer1 #ahae--,steam pressure1 #aej lbs4--,boiler making--,comparison with ,watt's engine--,blue-fire--,steam--,patent specification--,steam-ring stuffing box--,engines in ,lima--,a #cc-;inch pole-puffer more powerful than a #gb-;inch ,watt engine--,description of pole engine and boilers--,trevithick's calculation--,trial of ,herland engines--,steam-cushion--,power of the pole-engine--,defective workmanship--,sims examines the pole-engine--,opposition from shareholders--,defective boilers--,challenge to ,woolf--,davies ,giddy's opinion--,first cost1 and cost of working one-third of the ,watt engine--,meeting of opposing shareholders--,duty of the high-pressure steam pole puffer-engine1 #ahaf--;,comparison with the ,watt engine--,combined high-pressure pole and cylinder for expansion--,wheal ,alfred ,watt engine converted to high pressure--,wheal ,chance combined engine--,mr4 ,michael ,williams's opinion--,woolf and ,trevithick ,page #fi-aac ,,chapter ,,xx4 ,,the ,,watt ,,and ,,the ,,trevithick ,,engines ,,at ,,dolcoath4 ,early steam-engines--,semicircular boiler1 #agge1 net power #g lbs4 on the inch--,watt's statement in #aggg--;,engines in ,dolcoath--,watt's engine1 #aggh--,watt's engine at ,herland1 #agih--,trevithick's tubular boiler1 #agii--,reconstruction of the ,carloose #de-;inch1 #agii--;,gross and net power of engines--,comparison of ,newcomen1 ,watt1 and ,trevithick engines--,boiler explosion1 #ahjc--,strong rivalry with ,watt--,locomotive at ,coalbrookdale1 #ahjc--,watt's proposed locomotive--,competition in ,wales--,numerous high-pressure engines1 #ahjc--,patent difficulty--,watt's opposition1 #ahjd--;,government inquiry--,competitive trials in ,wales--,tramway locomotive1 #ahjd--,the bet--,opposition because of saving of labour--,worcester engine--,west ,india ,docks engine--,high-pressure steam condensing engines--,one or two cylinders for expansion--,sirhowey boilers--,mr4 ,homfray's opinion of the ,watt opposition--,mr4 ,whitehead makes engines in ,manchester--,cylindrical tubular boiler in ,wales for large engines1 #ahje--,watt contests at ,dolcoath1 #ahje--,steam-blast--,superiority of high-pressure whim-engines--,proposed boiler for the large pumping engine1 #ahjf--,steam pressure--,the ,watt boiler--,comparison of size of fire-place and coal used--,dredger contract--,theory of steam--,trevithick's ,dolcoath boiler when applied to the ,watt engine1 with expansive gear1 to save #cjjl4 monthly1 #ahjf--,momentum of pumping engine--,continued tests of high and low pressure whim-engines at ,dolcoath--,watt engine put aside1 #ahjf--;,high-pressure engines ordered1 #ahjf--;,high-pressure pumping engine for ,wheal ,abraham1 #ahjf--;,disputed patent right--,expansion reduces heat--,boiler for the ,watt #fc-;inch engine1 #ahjf--;,cost of ,trevithick's boiler--,advantage of small tubes in boilers--,trinity ,board--,watt's steam-cylinder unsuitable for high steam1 #ahjf--,sims' trial of engines--,little fight--,tubular boilers1 #ahjf--;,high-pressure steam pumping engines1 #ahah--,reporter of engines--,application to ,government1 #ahaj--;,dolcoath engines and boilers--,high steam to the ,watt engine--,duty of engines1 #ahab--,watt's boiler thrown out--,expansive valve--,dolcoath manager--,saving by boilers and expansive working1 #ahab--,lean's reports--,increased duty of the three old ,dolcoath engines1 #ahad--gf-;inch engine1 #ahaf--hj1jjjl4 a year saved--,durability of engine--,its removal--,cylindrical boilers--,hornblower and ,watt engines--,davies ,gilbert's report1 #agih--,lean's report1 #ahaf--,watt's views of expansive working--,watt's steam of #a or #b lbs4 to the inch--,pole's statement--,engine at ,marazion1 #ahjd--,woolf in ,cornwall--,rees' ,cyclopdia--',encyclopdia ,britannica'--,application to ,parliament--,wheal ,towan--,newcomen and ,watt engines--,pompe--feu ',la ,belle ,machine1' ,dolcoath ,page #aad-aid ,,chapter ,,xxi4 ,,engines ,,for ,,south ,,america4 ,engines for ,lima1 #ahac--,uville's application to ,watt--,high-pressure model--,cerro de ,pasco mines--,uville's return in search of ,trevithick--,engines ordered--,pump-work--,modern pumping engines--,money difficulty--,weight of pieces--',sanspareil' of #ahac--;,expansive working--,quartz crusher--,locomotive for ,south ,america1 #ahac--,sketch of winding engine--,their simplicity of form--,power and cost of engines--,trevarthen and ,bull to accompany the engines--,a third man recommended--,boilers put together at ,cerro de ,pasco--,uville's arrest--,trevithick a shareholder--,vivian's application--,departure of machinery1 #ahad--,uville's agreement--,invoice of engines sent ,page #aie-bbj ,,chapter ,,xxii4 ,,peru4 ,agreement for working the ,peruvian mines1 #ahab--,uville and ,watt1 #ahaa--,uville and ,trevithick1 #ahac--,uville's opinion of ,trevithick--,estimated value of the mines--,machinery reached ,peru1 #ahae--,trevithick's departure from ,penzance1 #ahaf--,mr4 ,edmond's statement--,cerro de ,pasco mines in #ahej--,report from the ,viceroy of ,peru1 #ahaf--,report from the ,magisterial ,deputation of ,yauricocha1 #ahaf--;,despatch from the ,governor of the ,province of ,tarma1 #ahaf--,pumping engines at work--,the ,viceroy's reply--,report in the ',lima ,gazette1' #ahaf--,trevithick's reception at ,lima--,trevithick's report1 #ahag--;,differences between ,trevithick and ,uville--,trevithick's thoughtless acts--,his visit to the nunnery--,the ,lord ,warden proposed to erect a statue in silver to ,trevithick--,bust of ,trevithick in ,cornwall--,quicksilver--,sunk ship--,chili--,copper and silver mine--,departure from ,lima--,cerro de ,pasco mines ,page #bba-bei ,,chapter ,,xxiii4 ,,costa ,,rica4 ,gerard at ,punta de ,arenas1 in the ,pacific1 in #ahbb--,nicolas ,castro worked a gold mine1 #ahba--;,alverado's ore-grinding machine1 #ahbb--;,climate of ,costa ,rica--,mines in the ,cordillera--,canal from the river ,machuca to ,quebrada-honda--,castro's mine--,padre ,arias1 or the ,priest's mine--,trevithick and ,gerard's proposal for iron railroads1 c41 for the mines of ,costa ,rica1 #ahbg--,new line of road from ,san ,juan1 on the ,atlantic1 to the ,costa ,rica mines--,serapique ,river navigable--,trevithick's diary--,a mule track easily constructed--,comparative distance to the mines from the head of the ,serapique on the ,atlantic1 and ,punta de ,arenas on the ,pacific--,trevithick nearly drowned in the ,serapique--,nearly starved before reaching ,san ,juan--,performs a surgical operation--,designed the locomotive between breakfast and dinner--,robert ,stephenson and ,trevithick at ,carthagena--,nearly drowned in the ,magdalena--,saved by ,mr4 ,bruce ,napier ,hall--,trevithick nursed ,robert ,stephenson ,page #bfj-bge ,,chapter ,,xxiv4 ,,return ,,to ,,england4 ,bodmin ,school1 #ahbg--;,cube root--,trevithick's reception--,saving in ,cornish mines--,model gun--,gerard's return1 #ahbg--;,his meeting ,robert ,stephenson--,his remarks on ,costa ,rica--,montelegre's search for a better line of road--,mr4 ,m4 ,williams's proposal--,change of ,ministry1 and the gun-carriage--,model of iron packet-ship and engine--,robert ,stephenson's remarks on mining--,trevithick's rejection of purchase-money ,page #bgf-bhc ,,chapter ,,xxv4 ,,gun-,,carriage--,,iron ,,ships--,,hydraulic ,,crane--,,ice ,,making--,,drainage ,,of ,,holland--,,chain-,,pump--,,open-,,top ,,cylinder--,,hayle ,,harbour--,,patent ,,rights--,,petition ,,to ,,parliament4 ,trevithick's description of gun-carriage and iron ship--,select committee--,glasgow iron-ship builders--,trevithick's comparison of gunpowder and steam--,cranes worked by air or water--,artificial cold--,liberality--,holland--,drainage-- ,dredging--,zuyder ,zee--,hydraulic crane--,dutch pumping engine--,chain-pump--,haarlem ,lake--,rhine--,windmills--,hayle ,harbour--,disputed pole-engine patent right--,petition to ,parliament1 #ahbh--,marine boilers--,steam pressure--,engine duty--,lords of the ,treasury refuse the petition--,davies ,gilbert's views--,marine compound engine of #ahga ,page #bhd-cad ,,chapter ,,xxvi4 ,,tubular ,,boiler--,,superheating ,,steam--,,surface ,,condenser4 ,binner ,downs engine1 #ahbh--;,fires around cylinder and steam-pipes--,saving of coal--,surface condensation at sea--,superheating tubes--,used steam returned to the boiler1 #ahbh--;,holland pumping engine--,woolf at the ,consolidated ,mines--,laws of steam--,power of heat from #a lb4 of coal--,loss of heat--,experiments at ,binner ,downs--,surface condensation--,partial surface condensation for ships or railways--,effect of superheating--,watt's theory doubted--,wheal ,towan and other engines--,loss of heat--,injection-water--,surface condensation and superheating--,partial condensation engine--,duty of chain pumping engine--,surface condensation by cold water or air--,results of the experiment--,hayle ,harbour--,condenser of copper tubes1 #ahbi--,suitability for steam-ships--,proposal to erect at his own expense a marine engine with surface condenser and screw-propeller for the instruction of the ,admiralty1 #ahcj4--,sketch of tubular boiler and surface-air condenser--,screw draught--,preservation of heat in condensing by air--,comptroller of the ,navy--,patent of #ahca--;,boiler within the condenser--,surface condensation by air or water--,safety boiler of concentric tubes--,blowing vessel for air condensation and draught--,tubes for distilling water--,steam pressure--,expansive working--,robert ,stephenson's statement--',echo' steamboat1 #ahca--;,bottle-neck boiler--,admiralty--,steam ,users' ,association--,mr4 ,alexander ,crichton's boiler and surface condenser--,captain ,dick and ,captain ,andrew--,captain ,king and the ',echo' ,page #cae-cfb ,,chapter ,,xxvii4 ,,heating ,,apparatus--,,marine ,,steam-,,engines--,,reform ,,column4 ,ill health1 #ahcj--;,hot-house boiler--,heating rooms--,discharging coal-ships by steam--,hot-water stoves for ,france--,patent for heating apparatus1 #ahca--,marine portable engines--,boat propeller--,wheal ,towan--,discharging coal by steam at ,hayle--,proposal to the ,common ,council of ,london--,every vessel to carry a steam-engine--,mr4 ,george ,rennie--,proposal to the ,admiralty--,surface condensation--,locomotives supplying their own feed-water--,petition in ,trevithick's favour--,davies ,gilbert's suggestion--,his comparison of the ,watt and ,trevithick engines--,maudslay on ,trevithick's proposals--,patent of #ahcb--,superheating steam--,cylinder placed in flue from boiler--,expansive steam--,tubular boiler--,water propulsion--,superheating and surface condensation for locomotives--,detail of engine--,proposal to send steamboats to ,buenos ,ayres--,waterwitch ,company--,messrs4 ,hall and ,sons--,hall's condenser--,rennie and the ,admiralty--',syria' steamboat--,compound engines--,watt on high-pressure steam--,trevithick on compound engines--,tubular boiler and variable blast-pipe--,refusal of ,trevithick's petition to ,government--,ill health--,davies ,gilbert's statement to ,spring ,rice--,meeting on proposed ,reform ,column--,trevithick's description--,means of ascent and descent--,placed before the ,king--,death--,funeral--,his last letter ,page #cfc-cif ,,illustrations ,,to ,,volume ,,ii4 ,,page ,a,,rated ,,steam-,,boiler #g ,,rock ,,splitting #be ,,steam ,,thrashing ,,engine #cg ,,agricultural ,,machine #eh ,,wheal ,,prosper ,,high-,,pressure ,,steam ,,pole-,,engine #gj ,,cylindrical ,,high-,,pressure ,,steam-,,boilers #ga ,,expansive ,,steam ,,pole-,,engine #ha ,,carn ,,brea ,,castle #adg ,,trevithick',s ,,dolcoath ,,engine ,,of #ahaf #afh ,,trevithick',s ,,dolcoath ,,boilers ,,of #ahaa #afi ,,steam ,,diagram #ahe ',,la ,,belle ,,machine' #aij ,,carriage-,,wheels #bjg ,,winding ,,engines #bjh ,,penzance ,,in ,,olden ,,time #bbh ,,market1 ,,jew ,,street1 ,,penzance #bdc ,,mule ,,track ,,from ,,lima ,,to ,,cerro ,,de ,,pasco #beh ,,map ,,of ,,costa ,,rica ,,mines #bfj ,,gun-,,carriage #bhe ,,dutch ,,pumping ,,engine #bih ,,mount',s ,,bay #cah ,,partial ,,condensation ,,engine #ccb ,,tubular ,,boiler ,,and ,,condenser #cci ,,bottle-,,neck ,,boiler #ceg ,,captain ,,dick ,,and ,,captain ,,andrew #cfa ,,hot-,,water ,,room-,,warmer #cfd ,,patent ,,heating ,,apparatus #cff ,,duck',s-,,foot ,,paddle #cfi ,,marine ,,engine ,,and ,,boiler #chj ,,compound ,,marine ,,engine #che ,,reform ,,column ,,in ,,detail #cia ,,general ,,view ,,of ,,reform ,,column #cic ,,life ,,of ,,trevithick4 ,,chapter ,,xvii4 ,,various ,,inventions4 ,about #ahjd ,captain ,trevithick put up in ,dolcoath ,mine a stone-crushing mill1 having large cast-iron rollers1 for breaking into small pieces the large stones of ore2 it was spoken of as the first ever used for such a purpose2 the same form of crusher is still used in the mines4 ,it caused a great saving compared with breaking by a hand hammer4#a ,i saw at the ,weith ,mine in #ahje a portable high-pressure engine1 made by ,captain ,trevithick4 ,it was called a puffer2 the cylinder was in the boiler2 the steam about #cj lbs4 on the inch above the atmosphere4 ,a wooden shed sheltered the engine and man4 ,the facility of manufacture and cheapness of those engines caused them to be much used in the mines1 and also elsewhere4#b ,footnote #a3 ,recollections of the late ,captain ,charles ,thomas1 manager of ,dolcoath4 ,footnote #b3 ,captain ,samuel ,grose's recollections4 ,mrs4 ,trevithick1 about the time we are speaking of1 accompanied her husband through one of the ,staffordshire china manufactories4 ,trevithick said to the manufacturer1 ,you would grind your clay much better by using my cast-iron rolls and high-pressure steam-engine4 ,the manufacturer begged him to accept a set of china4 ,mrs4 ,trevithick was disappointed at hearing her husband say ,no6 ,i have only told you what was passing in my mind4 ,driving rolling-mills was among the early applications of the high-pressure steam-engines2 but pulverizing hard rock by the use of iron rollers was a novelty3 though his patent of #ahjb shows the proposed rolls driven by steam for crushing sugar-canes1 yet no one had dreamt1 prior to #ahjd1 of economy in crushing stone and clay by such a means4 ,the plan1 however1 remains in use to this day in many mines1 and is frequently spoken of under the name of quartz-crusher4 ,,mr4 ,,giddy1 ,,coalbrookdale1 ,september #bcrd1 #ahjd4 ,sir1--,yours of the #acth this day came to hand4 ,i left ,wales about eight weeks since1 and put an engine to work in ,worcester1 of #aj-;horse power1 for driving a pair of grist-stones1 and a leather-dressing machine1 and another in ,staffordshire for winding coals2 each of them works exceedingly well4 ,from ,coalbrookdale ,i went to ,liverpool1 where a founder had made two of them1 which also worked exceedingly well2 one other was nearly finished1 and three others begun4 ,some ,spanish merchants there saw one of them at work1 and said that as soon as they returned to ,spain they would send an order for twelve engines1 of #ab-;horse power1 for ,south ,america4 ,in ,south ,america and the ,spanish ,west ,indies water is very scarce2 in several places there is scarcely water for the inhabitants to drink1 therefore there is no water for any engine4 ,by making inquiry1 ,i found that ten mules would roll as much cane in an hour as would produce #bej gallons of cane-juice1 which they boil until the water is evaporated1 and the sugar produced4 ,i told them that the engine-boiler might be fed with this juice1 and by a cock in the bottom of the boiler constantly turning1 and by taking a greater or smaller stream from it1 they might make the juice as rich as they liked4 ,in this process the juice would be so far on towards sugar1 and the fire that worked the engine would cost nothing1 because it would have taken the same quantity of fuel under the sugar-pans to evaporate the water1 as it would in the engine-boiler4 ,the steam from the engine might be turned around the outside of the furnace for distilling rum1 as the distilleries require but a slow heat4 ,i think the steam would answer a good purpose around the outside of the pan4 ,if this method answers1 the cost of working the engine would be nothing1 and the engine would be then working1 as it were1 without fire or water4 ,the ,spaniards told me that if this plan answers1 they would take a thousand engines for ,south ,america and the ,spanish ,west ,indies4 ,i shall be very much obliged to you for your opinion on this business4 ,these merchants make a trade of buying up sugar mills and pans1 with every other thing they want from ,england1 and exchange them with the ,spaniards for sugar4 ,at ,manchester ,i found two engines had been made and put to work2 they worked very well3 three more are in building4 ,from there ,i went to ,derbyshire4 ,the great pressure-engine ,i expect will be at work before the middle of ,october4 ,a foundry at ,chesterfield is building a steam-engine as a sample2 two foundries in ,manchester are at full work on them1 and one in ,liverpool4 ,there are six engines nearly finished at ,coalbrookdale1 and seven in a foundry at ,bridgenorth4 ,i am making drawings for several other foundries4 ,any number of them would sell4 ,a vast number are now being erected1 and no other engine is erected where these are known4 ,the engine for the ,west ,india ,docks was neglected during my absence from the ,dale1 but ,i expect it will be ready to send off in ten days4 ,in about three weeks ,i shall be in ,london to set it up4 ,it will please you very much1 for it is a very neat and complete job1 and ,i have no doubt will answer every purpose exceedingly well4 ,at ,newcastle ,i found four engines at work1 and four more nearly ready2 six of these were for winding coal1 one for lifting water1 and one for grinding corn4 ,that grinding corn was an #aa-;inch cylinder1 driving two pair of #e-;feet stones #abj rounds per minute2 ground #aej winchesters of wheat in twelve hours with #ab cwt4 of small coal4 ,it worked exceedingly well1 and was a very complete engine1 only the stroke was much too short1 not more than #b feet #f inches1 which made very much against the duty4 ,the other engine that was lifting water had a #e-a_/b-;inch diameter cylinder1 with a #c-;feet stroke1 drawing #ajj-;gallon barrels1 twenty-four every hour1 #hj yards1 burning #e cwt4 of coal in twenty-four hours4 ,this work it did with very great ease4 ,i believe you will find this an exceeding good duty for a #e-a_/b-;inch cylinder engine4 ,below ,i send a copy of ,mr4 ,homfray's and ,mr4 ,wood's letters to me3-- ,mr4 ,homfray's1 of the #ajth ,september4--',our great engine goes on extremely well here1 nothing can go better2 the piston gives no trouble2 it goes about three weeks1 and we work it with blacklead and water2 the cylinder is as bright as a looking-glass2 it uses about #b lbs4 of blacklead in a week2 about once in twelve or fifteen hours we put a small quantity of blacklead1 mixed with a little water1 through the hole in the cylinder screw1 and we never use any grease4 ,we rolled last week #adj tons of iron with it1 and it will roll as fast with the both pair of rolls1 as they can bring to it4' ,mr4 ,wood's letter1 ,september #abth4--',we are going on1 as it is likely we always shall1 in the old dog-trot way1 puddling and rolling from the beginning of the week till the end of it4 ,your engine is the favourite engine with every man about the place1 and ,mr4 ,homfray says it is the best in the kingdom4' ,i have not the smallest doubt but that ,i can make a piston without any friction or any packing whatever1 that needs not to have the cylinder screw taken up once in seven years4 ,it is a very simple plan1 and will be perfectly tight2 it is by restoring an equilibrium on both sides of the piston4 ,i expect to see you in ,london soon1 and then will give you the plan for inspection before ,i put it in practice4 ,i am very much obliged to you for recommending these engines in ,cornwall1 but you have not stated in what manner they are to be applied2 whether to work pumps1 or barrels1 or both4 ,they may be made both winding and pumping engines at the same time1 if so required4 ,a rotative engine will cost more than an up-and-down-stroke1 on account of the expense of the fly-wheel and axle4 ,an engine capable of lifting #ahj gallons of water per minute #bj fathoms would cost1 when complete and at work1 patent right included1 about #bbjl4 ,if it is a rotative engine1 with a winding barrel1 it will cost #bgjl4 ,i expect that a #g-;inch cylinder would be sufficient for winding at ,penberthy ,crofts1 which might have a ,crank on the fly for lifting water in pumps1 and a winding barrel on its back4 ,this would cost about #agjl42 the erection of them1 when on the spot1 will cost nothing4 ,you do not say when you intend to be in town4 ,i hope you will be present when the dock-engine is set to work4 ,the engines first sent to ,cornwall1 must be from ,coalbrookdale2 then they will be well executed1 but from ,wales it would not be so4 ,you may depend on having a real good engine sent down1 with sufficient openings given to the passages4 ,the engineer from the ,dale has been lately in ,london1 and has just returned2 he gives a wonderful account of the engines working in ,london4 ,there are twelve now at work there4 ,they have well established their utility in different parts of the kingdom1 and any number would sell4 ,the founders intend to make a great number1 of different sizes1 and send them to different markets for sale1 completely finished1 as they stand4 ,you do not say anything about wheels to the engine for ,penberthy ,crofts4 ,there are several engines here nearly finished2 if they suit in size for ,penberthy1 one may be sent down in four or five weeks1 otherwise it may be two months4 ,i am1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,direct for me at the ,talbot ,inn1 ,coalbrookdale4 ,trevithick worked hard and successfully in making his steam-engines useful1 and firmly believed that he could and would make them universal labourers4 ,even the ,spanish merchants1 unacquainted with steam1 talked of giving an order for several engines for ,south ,america2 and their glowing account of the wide field open to him may have been instrumental to his going to that country by making his engines known there4 ,his proposal to make the sugar-cane convert itself into sugar by the use of his patent high-pressure steam-engine may be more theoretical than practical2 but many more unlikely things have come to pass4 ,at that time several of his engines were at work in ,wales1 ,worcester1 ,staffordshire1 ,coalbrookdale1 ,manchester1 ,derbyshire1 ,liverpool1 ,cornwall1 and ,newcastle-upon-,tyne4 ,twelve were at work in ,london1 and so familiar were people with them1 that founders intended to construct them of different sizes1 and send them for sale at the large market or county towns2 their cost complete1 ready for work1 to be #bjjl41 more or less1 according to size1 with a range of application unlimited4 ,his one letter1 casually written sixty-seven years ago1 mentions them as grinding corn1 dressing leather1 winding coal1 crushing sugar-cane1 prepared to boil sugar1 and distil rum2 pumping water1 rolling iron1 railway locomotion1 portable steam fire-engine1 portable steam-crane1 mine engines on wheels2 so that it may almost be said he was not too sanguine in hoping to send in #ahjd a thousand of his engines to ,south ,america1 for in those cursory remarks he draws attention to no less than thirty-six high-pressure steam-puffers at work4 ,the ,penberthy ,croft ,mine portable engine could be placed on wheels or otherwise1 according to the wish of the purchaser1 as though steam locomotion was an every day occurrence in #ahjd4 ,,camborne1 ,january #acth1 #ahaa4 ,,mr4 ,,giddy1 ,sir1--,from calculating the quantity of blast given to a blast-furnace1 ,i find a considerable quantity more of coal consumed by the same quantity of air in this way1 than by the usual way in common engine chimneys4 ,of course the more cold air admitted to pass through the fire1 the more heat carried to the top of the stack4 ,crenver #fc-;inch cylinder1 double-power1 #h-;feet stroke1 with but one boiler1 works five strokes per minute4 ,this gives about #afjj square feet of steam per minute1 and burns about #h tons of coals in twenty-four hours4 ,the stack for this boiler is #c-a_/b feet square1 and the draught rises #aj feet per second1 and will set white paper in a flame at the top of it in about a minute4 ,therefore1 this chimney delivers #gbjj square feet of air per minute1 which is four and a half times the quantity of heated air1 at nearly four times the temperature of heat that there is of steam produced from the same fire1 and delivered to the cylinder4 ,a blast-furnace that burns #ajj tons of coal per week is blown by a #e-;feet diameter air-cylinder1 #d-;feet stroke1 ten strokes per minute1 double-power1 giving about #afjj square feet of air per minute1 to consume #ajj tons of coal1 besides giving a melting heat to #cej tons of ore and limestone4 ,crenver engine has #gbjj square feet of air to burn #ef tons of coal per week1 which is above eight times the quantity of air used by air fire-places to what is used in a blast-furnace1 and of course must carry off a great proportion of the heat to the top of the stack1 that might be saved if the engine-fire was a blast instead of an air fire4 ,but suppose the idea to be carried still further1 by making an apparatus to condense and take the whole of the heat into the cylinder instead of its passing up the chimney4 ,by having a very small boiler1 and a blast-cylinder to blow the whole of the blast into the bottom of the boiler1 under a cylinder full of small holes under the water1 to make the heated air give all its heat to the water4 ,illustration ,the furnace must be made in a tight cast-iron cylinder4 ,both the fire-door and the hole through which the blast enters must be quite tight1 as the pressure will be as strong in the fire-place as in the boiler4 ,the whole of the air driven into the fire-place1 with all the steam raised by its passage up through the water in the boiler1 must go into the cylinder4 ,there will also be the advantage of the expansion of the air by the heat over and above what it was when taken cold into the blast-cylinder4 ,from the great quantity of coal burnt in blast-furnaces you will find that a very small blast-cylinder would work a #fc-;inch cylinder double4 ,if there is as much heat in a square foot of air as in steam of the same temperature1 the saving will be beyond all conception2 but for my own part ,i cannot calculate from theory what the advantages will be1 if any1 and for that reason1 before ,i drop or condemn the idea1 ,i must request you will have the goodness1 when you have an hour to spare1 to turn your thoughts to this subject1 and inform me of your sentiments on it4 ,perhaps it is like many other wild fancies that fly through the brain1 but ,i did not like to let it go unnoticed without first getting your opinion4 ,i hope you will excuse me for so often troubling you4 ,st4 ,ives plans will be delivered to them on ,tuesday1 when ,i expect they will be forwarded to you4 ,i hear there is a good course of ore in the adit end at ,wheat ,providence ,mine4 ,a ,mr4 ,sheffield1 of ,cumberland1 writes to ,mr4 ,gould that he has turned idle his air-furnaces1 and smelted his ores by a blast near a year since4 ,his furnace is but #aj feet high and #d feet diameter1 and it melts #bh tons of ore1 of from #d to #e in the #ajj per week1 and makes a regel of from #fe to #gj in the #ajj1 and answers beyond what we calculated for them4 ,suppose a furnace #bj feet high and #d feet diameter1 it would smelt eight times the quantity of his1 which would be near #ijj tons per month1 or nearly double the quantity raised by any one mine in the country4 ,the expense of the 444 would be very trifling4 ,to-morrow ,dolcoath account will be held1 when ,i expect to have orders to begin to erect a furnace on the spot4 ,this trial of ,mr4 ,sheffield's has put it out of my power to get a patent1 and now ,i do not know how to get paid4 ,i should be content with #e per cent4 on the profits gained by this plan1 and would conduct the business for the mines without salary4 ,should you chance to fall on the subject with his ,lordship1 be pleased to mention something about the mode of my payment1 as his ,lordship is by far the properest person to begin with about my pay1 for after his ,lordship has agreed to the sum1 and ,dolcoath ,mine the first to try the experiment1 ,i think all the county will give way to what he might propose4 ,but ,i wish something to be fixed on before all the agents in the mines know how to be smelters themselves1 after which ,i expect no favour1 unless first arranged4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,how great was the practical insight his genius gave him1 and how imperfectly his followers have acted on this advice given sixty years ago6 ,the chimney that at its top would ignite paper1 threw to waste four and a half times more heated air than was requisite to supply the quantity of heat which passed through the working cylinder in steam1 and at a temperature nearly four times greater than the temperature of the steam4 ,it needs only to observe the burnt appearance of a steamboat funnel of the present day to know how wasteful we still are1 or how very ignorant of improved methods of economizing fuel4 ,to prevent this waste of heat up the chimney be proposed to do away with the chimney altogether2 the fire-place was to be a close one1 having a blast under the fire-bars of a strength sufficient to force the air1 heated by its passage through the fire1 direct through a small valve into the water in the boiler1 by which means all the heat given by ignition would pass into the steam1 and his steam-puffer become an arated steam-engine4 ,from the following it appears that this plan of ,trevithick's is now coming into use as something quite new3-- ,in your last impression1 under the head of ',air and ,steam combined1 as a ,motive ,power1' you state 'the invention was described to be that of ,mr4 ,warsop1 but we have recently heard that a few years back 7#ahfe7 the same invention had been protected in an earlier patent than ,mr4 ,warsop's1 by ,mr4 ,bell ,galloway4'#c ,trevithick thought of patenting a plan for reducing copper ore by the use of a blast1 in preference to the usual air-furnace and chimney1 but something similar had been tried by ,mr4 ,gould1 and he therefore proposed to erect a blast-furnace in ,dolcoath ,mine1 receiving a portion of the saving of fuel as his remuneration4 ,such a furnace worked there for many years1 until copper smelting was removed from ,cornwall to ,wales4 ,the plans for a breakwater at ,st4 ,ives were for an undertaking that has since been in many hands1 but without success1 except perhaps for the convenient making of members of ,parliament4 ,some slight progress has been made by engineers and contractors1 but vessels are not willingly taken to the port1 and ratepayers grumble at unprofitable harbour taxes4 ,,london1 ,january #bjth1 #ahaa4 ,,dear ,,trevithick1 ,i have not lost any time in mentioning your wishes respecting a compensation for the plan of smelting copper to ,lord ,dedunstanville1 who intends mentioning the affair in his next letter to ,mr4 ,reynolds4 ,lord ,dedunstanville wishes you extremely well1 but it is impossible for him to settle anything apart from the adventurers4 ,footnote #c3 ,see the ',mechanics' ,magazine1' ,june #crd1 #ahgj4 ,i am very sorry that anyone should have executed the plan of reducing copper ore by a blast-furnace before you had put into practice the idea suggested to me ten years ago4 ,it ascertains1 however1 that the contrivance will succeed1 although you are certainly reduced to ask moderate terms1 and ,i know not what can be more moderate than those you have asked1 except that ,i would recommend some limit as to time4 ,the plan you suggest for an engine on a new construction is1 ,i fear1 very doubtful4 ,according to the data furnished to me1 the air in the blast would be to that in a common fire-place as #f-a_/d to #a very nearly1 provided their densities were the same2 but you have measured one entering the furnace at the common temperature1 and the other going to the stack so hot as to set on fire a piece of paper held at the top4 ,thus the increase of temperature that augments the elasticity of a fluid confined1 would expand it in the same degree4 ,it is therefore uncertain from these statements which furnace consumes the greater quantity of air4 ,i apprehend the general principles of an engine worked by hot air1 through the medium of a blast1 would be as follows3-- ,let any quantity of air be driven into a furnace with the pressure of an atmosphere1 and let it be there expanded ten times4 ,it should then be taken off ten times as quick1 but in that case no power whatever would be produced1 so the external atmosphere would balance the internal4 ,now1 let the blast be two atmospheres strong1 and let them be expanded ten times1 and be taken off ten times as fast1 each stroke will be opposed by one1 equal in all to ten2 subtract two for the blast1 there remain eight4 ,but air so hot would burn every vegetable or animal substance1 and such a furnace ,i suppose could scarcely be kept air-99tight4 ,if the heated air is made to act on water1 then it becomes a mere question of how much absolute heat is given out by the fuel1 and whether that excess is more than sufficient to compensate the burden of the blast2 for the water will absorb an immense quantity of heat in changing itself into steam1 and thus reduce the force of the air as to make it almost impossible for that addition to add so much power as the blast takes away4 ,i have1 therefore1 no hesitation in saying that this plan will certainly not do4 ,write to me by all means whenever anything strikes you1 and you may always depend on having my best advice4 ,i am1 dear ,sir1 ,ever most truly yours1 ,,davies ,,giddy4 ,trevithick saw without apparent reasoning1 while his friend's reasonings failed to make plain the full bearing of the questions1 and so cramped the position as to make a change of front difficult--an operation in which ,trevithick excelled4 ,we learn1 however1 that in #ahja he suggested a blast in copper-ore furnaces1 and in #ahaa was on the verge of a discovery that has since revolutionized the iron-smelter's art by the use of hot blast4 ,wasted heat from a blast-furnace #aj feet high led him to the conclusion that by doubling the height of the furnace1 enabling the cold mineral thrown in at the top to take up the heat wasted through the top of the low furnace1 seven-eighths of the coal would be saved4 ,his idea of sending blast through the furnace of his steam-boiler to economize heat could have been readily applied to the iron furnace1 and we should have had the modern hot-blast iron furnaces4 ,rough draft4 ,,camborne1 ,march #eth1 #ahab4 ,,gentlemen1 ,your favour of the #aeth ,february1 with a sketch of your brewery1 ,i have received2 and from which ,i find the head of water is #cj feet above the brewery1 which makes it difficult to erect the chain and buckets so as to take advantage of the whole height of water2 and as the stream is so very small1 it will not admit of losing any part of the power4 ,to erect a machine so high1 to engage the whole fall1 would be1 ,i fear1 more expense than the power you would get would warrant2 therefore ,i would recommend it to be made use of in a cylinder1 in the same way as we use falls of water of #bjj feet in our ,cornish copper mines4 ,we allow one-third loss for friction and leakage in those machines2 but your machine being so very small1 the loss will exceed that proportion2 therefore ,i cannot promise you above one-half of the real weight and fall to be performed on your machinery1 and that must be by a well-executed machine1 for a small defect would destroy the value of so trifling a power4 ,as there is no expansion in water1 it will be somewhat difficult to make the machine turn the centres with a fly-wheel1 for if the valve shuts a little too early or too late for the turn of the crank over the centre1 the fly-wheel's velocity must break something by confining the water between the piston and the bottom of the cylinder1 which1 after the valve is shut1 cannot make its escape1 and not having an elastic principle1 the piston will strike as dead on the water as on a piece of iron1 because1 unless the valve is shut by the engine before the stroke is finished1 it cannot shut at all4 ,i know persons who have attempted to put fly-wheels on pressure-engines of this kind1 but never yet has one been made to work rotative4 ,i do not see much difficulty in making an engine of this kind to work a crank and fly-wheel1 by connecting an air-vessel with the cylinder to receive the pressure and contract and expand and shut the valves1 the same as in steam-engines4 ,a machine on this plan ought to be placed as near the low level as possible4 ,if ,i furnish you with drawings and directions for the executing of the work yourselves1 ,i shall charge you fifteen guineas for them4 ,if ,i send the machine finished1 the charge will be #ejl4 ,your objections respecting steam-engines ,i do not doubt are correct1 when executed by persons who do not understand the construction of them4 ,in ,england some persons privately erected my engine to evade the patent premium1 but have severely paid for their saving knowledge by accidents and defects in their engineering ability4 ,i have erected above #ajj steam-engines on this principle1 but never met with one accident or complaint against them4 ,to prevent mischief from bad castings1 or from the fire injuring the surface of cast iron1 ,i make the boilers of wrought iron1 and always prove them with a pressure of water1 forced in equal to four times the strength of steam intended to be worked with4 ,some persons have worked those engines under a pressure above #ajj lbs4 on the square inch1 but in general practice ,i do not exceed #bj lbs41 finding under this pressure the piston will stand six or eight weeks1 and the joints remain perfect1 and no risk of bursting the boiler1 it being made of wrought iron1 and proved by pressure before sent off2 but cast-iron boilers may1 by defects not discernible1 and are very apt to break by the water being left low in the boiler1 and if heated red hot1 exploding without the smallest notice2 but wrought-iron boilers1 when defective1 give way only partially1 without injury to anyone4 ,with respect to the erecting and management of the engine1 you need not have an engineer1 for any common tradesman can do this from the drawings and directions sent with the engine2 for1 as ,i before informed you1 farmers and their labourers set up and keep in order the thrashing-machine engines without my going on the spot or sending any person to assist them4 ,i never saw a steam-engine rolling malt1 therefore cannot judge the quantity the engine would roll1 only by a comparison with horse labour1 against the consumption of coal1 which will be in some cases as about #db lbs4 to one horse2 but where great speed is required in the machine1 the coal will be less1 as steam-engines make more revolutions in a minute than horse mills1 therefore the work is done with less friction4 ,i have several times applied the steam1 after it has worked the engine1 to boil water and other purposes1 with as good effect as if the engine had not been there1 therefore the work of the engine will be a clear profit4 ,you say about a #a-;horse engine4 ,the boiler would be so small that it would not be worth applying that steam to any other purpose1 as any large quantity of water would be but slowly heated4 ,i find that it does not answer either the purpose of the vendor or the user of an engine1 to make less than a #b-;horse power1 as the expense on a very small engine is nearly as much as one of the power ,i use for thrashing1 those being only #hjl41 and a #b-;horse is #fjl4 ,respecting the mashing with steam1 ,i never before heard of it1 but from the theory of the plan ,i think it cannot fail to answer a far better purpose than any other that can possibly be applied for extracting the essence of the malt4 ,however1 should it not answer your purpose1 it is only the loss of the expense of a few yards of #a-;inch lead pipe4 ,in an engine of the size used for thrashing1 if the fire is kept brisk1 it will boil1 by the steam sent into a separate vessel1 near #cjj gallons of water per hour4 ,the room required to work in is about #g feet diameter1 and #ab feet high4 ,it would be useless to put you to the expense of drawings1 until you have made up your minds on what you intend to have done4 ,i remain1 ,gentlemen1 ,your most obedient humble servant1 ,,richard ,,trevithick4 ,to ,,robinson ,,and ,,buchanan1 ,brewers1 ,londonderry1 ,ireland4 ,engineers of the present day do not volunteer such general information without charge1 or give such a variety of practical mechanism slightly but clearly described1 and principles reduced to practice4 ,an endless chain with buckets is a form of water-wheel not then in use4 ,a water-pressure engine for so small a quantity of water1 with a fall of about #cj feet1 would cause a loss of #ej per cent4 from friction and small defects4 ,the non-elastic character of water made it unsuitable for a machine requiring a fly-wheel4 ,air-vessels should be used to lessen the rigidity of water4 ,cast-iron boilers dangerous4 ,wrought-iron boilers to be tested with a water pressure four times as great as the proposed working steam pressure4 ,a steam pressure of #bj lbs4 to the inch most suitable for engines in charge of inexperienced persons4 ,the brewers' mash tub to be heated by the waste or surplus steam4 ,rough draft4 ,,camborne1 ,december #eth1 #ahab4 ,,gentlemen1 ,i have yours of the #bjth ,november4 ,the letter you directed for ,truro never came to hand4 ,i find by your letter that you have been trying to put into practice the hints ,i gave you about the chain and buckets1 and that you expect it will answer if properly executed4 ,you are not the first that has picked up my hints1 and stuck fast in their execution4 ,i make it a rule never to send a drawing until ,i have received my fee1 and when you remit to me fifteen guineas ,i will furnish you with proper drawings and directions to enable you to make and erect the machine4 ,i remain1 ,gentlemen1 ,your very humble servant1 ,,richard ,,trevithick4 ,,robinson ,,and ,,buchanan1 ,brewers1 ,londonderry4 ,what a pocket encyclopdia of inventions6 from which1 as by stealth1 ,robinson and ,buchanan selected the least applicable1 declining a suitable steam-engine at a very small cost1 rather than pay an engineer for his opinion4 ,rough draft4 ,,camborne1 ,april #bfth1 #ahab4 ,,sir ,,charles ,,hawkins1 ,bart41 ,sir1--,i have received yours of the #gth1 respecting the small breakwater at ,st4 ,ives4 ,as far as ,i can judge from a rough calculation1 ,i think it an undertaking likely to pay well2 but as you wished me not to mention anything about your intentions1 and not receiving your orders to make a minute inquiry and estimate1 ,i cannot answer your letter so fully as ,i should wish1 fearing that giving a random and imperfect statement might be apt to lead you into errors1 and also make me look simple4 ,if an engineer were employed to survey and estimate after me1 every information in my power is at your service2 therefore be pleased to state particularly what information you wish1 and ,i will attend to the business and answer your questions as early as possible4 ,i have received a letter from ,sir ,john ,sinclair requesting correct drawings and statements of the thrashing engine to be forwarded to the ,president of the ,board of ,agriculture1 which ,i shall attend to4 ,he also says that he has sent my letter to the ,navy ,board1 in hopes that the experiment of propelling vessels by steam may be tried under its sanction and expense4 ,perhaps it might be proper to wait the answer of the ,navy ,board before writing to ,mr4 ,praed about propelling the canal boats4 ,i am very much obliged to you for writing to ,captain ,gundry1 about the ,wheal ,friendship engine4 ,i expect to have a portable steam-whim and stamps at work at my own expense in a few days1 which will prove for itself its utility2 that being the only way to introduce new things4 ,i would be very much obliged to you to say if ,mr4 ,halse is to pay me for my past attendance at ,st4 ,ives about the breakwater4 ,enclosed you have a letter to ,sir ,john ,sinclair1 unsealed for your inspection1 which1 if you approve of1 please to forward4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,trevithick's skill did not prevent his being reasonably modest1 or cause him to be envious of others2 neither did his dear-bought experience1 that one's own pocket must pay for making public one's own inventions1 prevent his again soliciting the assistance of persons of influence1 though it does not seem that ,mr4 ,praed helped forward the screw-propeller1 or that ,sir ,john ,sinclair gave direct help1 though he probably made known the high-pressure steam-engine to the marine experimenters on the ,clyde4 ,rough draft4 ,,mr4 ,,rastrick1 ,,camborne1 ,december #gth1 #ahab4 ,sir1--,i have been waiting your answer to my last1 and especially that part respecting the ,west ,india engine1 as ,i have not nor could not answer their letter to me without first hearing from you2 therefore must beg you will be so good as to answer me by return of post on that subject4 ,if they get impatient about the time1 and refuse to take the engine1 ,i have no doubt the ,plymouth people will take it and several others2 but ,i very much wish to send one to the ,west ,indies1 as there is a large field open there for engines of this kind4 ,i have received an order for a thrashing engine for ,lord de ,dunstanville1 of ,tehidy2 and as ,i wish those thrashing engines to be known through the country1 ,i intend to take one of the engines ordered for ,padstow and send it to ,tehidy4 ,one of the ,padstow farmers can wait until you make another for him4 ,therefore ,i would thank you to send the first finished by ship from ,bristol for ,portreath or ,hayle4 ,send a drum with everything complete1 of which you are a better judge than ,i4 ,probably about #c feet in diameter and #c-a_/b feet long will be sufficient4 ,there must be a fly-wheel with a notch to carry the rope1 and also a small notch-wheel on the drum-axle4 ,i think #f-a_/b feet diameter for the fly1 and #i-a_/b inches diameter for the small wheel1 will give speed enough to the drum4 ,mind to cast a lump1 or screw on a balance1 of about #a cwt41 on one side of the fly-wheel4 ,there must be two stands on the boiler1 and a crank-axle1 or otherwise a crank-pin1 in the fly-wheel1 whichever you please2 with a shaft #c feet long with a carriage4 ,the engine is to stand in a room under the barn1 about #g-a_/b feet high1 #g feet wide1 and #ad feet long4 ,the fly-wheel will stand across the narrow way of the room4 ,the rope will go up through the floor1 and the drum be shifted by a screw1 horizontally1 on the barn floor1 so as to tighten the rope4 ,i shall put down the top of the boiler level with the surface1 with an arched way to the fire and ash-pit under ground1 to prevent the chance of fire1 which the farmers are very much afraid of4 ,i send you a sketch showing how it is to stand4 ,i do not bind you to the size of the drum or wheels1 only the room that the fly-wheel works in is but #g feet wide4 ,now to ,mr4 ,richards' mill4 ,query #ast4--,the length of the piston1 and the small variation that the beam will give it1 is so trifling that it will not be felt4 ,the cylinders that have been working on their sides for seven years past1 are now working as well as any engine with upright cylinders1 which is a proof that the little rubbing is of no consequence4 ,query #bnd4--,the passage in the cock is equal to the passage we make in our large engines1 which is only one-fortieth part of the piston2 and as we shall work with high steam1 we do not mind the pressing through the steam-passage2 and as the steam will be very much expanded1 it will not be felt in the passage to the condenser4 ,i know where we have removed cylinders and put larger ones on the same nozzles and condensing work1 and the engines did good duty4 ,query #crd4--,i find by experience that if you give double the quantity of injection to an engine one stroke1 and none the other1 that the quicksilver in the gauge will stand nearly the same2 the cold sides of the condenser are sufficient to work an engine a great many strokes without any injection4 ,query #dth4--,you may put a hanging to the air-pump bucket1 and foot-valve2 either that or a rising one will do very well1 but ,i think the rising cover and wood face on the top1 best4 ,query #eth4--,the air-pump bucket is large enough4 ,at ,wheal ,alfred they have a #fd-;inch cylinder2 the air-pump is #bj inches1 and the stroke is half that of the engine4 ,they were afraid that it was too small2 they then put another of #ad inches by the side of the first1 the same stroke4 ,the quicksilver tube stands as high with the one #bj-;inch bucket as with the two buckets2 the engine works best with the one bucket4 ,i have found by experience that size to be sufficient1 and 7especially in an engine that works quickly7 make the cistern high enough to cover the condensing work well with water4 ,query #fth4--,my reason for making the forcing pump with duck-valves is1 because they do not bum like the others1 and we find them seldom out of repair2 but make it whichever way you think best1 and work it in any way you like4 ,query #gth4--,i mean by #c_/d expansive1 that the steam is to be shut off from the cylinder when the piston has moved up from the bottom one quarter of its stroke4 ,make the cam to your own mind4 ,query #hth4--,i do not think the engine will require a heavier fly-wheel1 as the stones will act as a fly1 and the power1 though so very irregular1 will be so sudden in its changes1 that the speed of the machinery will not let it be felt4 ,if you make a crank1 you may make the fly-wheel #c or #d feet more in diameter4 ,but if with a pin in the fly-wheel1 the beam would come down on the top of it2 therefore1 ,i think it will be better to put a crank1 and put the fly-wheel in the middle of the shaft4 ,query #ith4--,the steam will be raised to #be lbs4 to the inch above the atmosphere1 or #dj lbs4 to the inch on a vacuum2 but ,i think you need not calculate for much more strength on that account4 ,it is not the power that breaks the machinery1 but bangs1 and not the uniform weight that this will give4 ,query #ajth4--,twenty strokes per minute ,i propose1 which ,i think a fair speed4 ,query #aath4--,the fire-bars must be of wrought iron2 we find them answer much better than cast iron4 ,let them be #e_/hths of an inch from bar to bar1 #a inch thick at the top1 #c_/hths of an inch at the bottom1 #b inches deep1 #d feet long1 with bits on them at the ends1 to prevent their getting too close together4 ,i find the nearer the fire is to the door1 the better and handier it is to work4 ,all the large engines are in this way1 and we do not find the door or front plate get hot1 as they are lined with brick4 ,cast the door with a rib to hold a brick on its edge4 ,tube1 #b feet #i inches by #a foot #aa inches2 manhole1 #ae by #aj inches4 ,query #abth4--,a governor will be required2 perhaps as good a place as any for it1 out of the way1 will be on the cast iron that carries the beam2 you may turn the fly-wheel whichever way you please4 ,if this engine is worked with steam of #be lbs4 to the inch above the atmosphere1 and the steam shut off at one-twentieth part of the ascending stroke of the piston1 the power will be as three is to two of ,boulton and ,watt's single engines4 ,only two pairs of stones for the present1 but calculate those stones to stand in such a way that another pair may be placed1 on a future day1 if wanted4 ,i have not seen ,mr4 ,richards lately4 ,i wish you to write a form of an order1 in your next1 such as you wish1 and ,i will get him to write to you accordingly4 ,put the engine and drum for ,lord de ,dunstanville out of hand neat and well1 as it will be well paid for2 and make the stands1 c41 in your own way4 ,,rd4 ,,trevithick4 ,mr4 ,richards' flour-mill engine may claim to be the first practical smoke-burner3 keeping the fire much thinner at the inner end of the grate-bars than at the fire-door end of the grate1 allowed of the freer passage of air through the thinner layer of coal1 near the fire-99bridge1 causing the combustion of the passing gas4 ,this idea has1 since the date of ,trevithick's letter1 led to several smoke-burning patents4 ,the boiler fire-tube was oval1 #b feet #i inches by #a foot #aa inches4 ,the open-topped cylinder was supplied with a heavy and deep piston serving as a counterweight1 and also as a guide in the cylinder for correcting the angle of the connecting rod4 ,experience had taught him that the cold sides of the condenser were sufficient to work an engine a great many strokes without a supply of injection2 and he had already used high-pressure steam of #be lbs4 to the inch above the atmosphere1 cut off from the cylinder when the piston had performed one quarter of its course3 thus both these things were as first steps leading to the modern expansive steam-engine and surface condensation4 ,the simplicity of the engine is remarkable--a high-pressure1 expansive1 condensing engine1 worked by a single four-way cock1 without cylinder-cover1 or parallel motion4 ,the low first cost1 and non-liability to derangement1 were always kept in view2 and his confirmed experience in the satisfactory working of horizontal cylinders prior to #ahab illustrates their extended application2 for at that time scarcely any other engineer had constructed other than upright cylinder engines4 ,no detail escaped his observant gaze4 ,the fire-bars were to be #b inches deep1 #a inch thick at the top edge1 tapered to #c_/dths of an inch at the bottom1 giving the required strength1 with free room for air1 which in its passage cooled the bar1 carrying the heat into the fire4 ,years before and after that period the fire-bar in common use by thoughtless people was a square iron bar that was always burning and bending4 ,the letter is descriptive of the high-pressure steam-engine in the sixteenth year of its age2 and its expansive steam1 made practical by ,trevithick's high-pressure boilers4 ,this engine only took steam during the first quarter of its stroke1 the remaining three-quarters were by the expansion4 ,had it taken steam only during one-twentieth of its stroke1 it would have been more powerful than ,boulton and ,watt's low-pressure steam vacuum engine of the same size4 ,rough draft4 ,,sir1 ,,camborne1 ,november #hth1 #ahab4 ,i have your favour of the #crd inst41 informing me that ,messrs4 ,fox and ,williams have engaged to quarry the stone for e breakwater at ,plymouth1 but does not say whether you hold any share with them in the contract or not4 ,therefore ,i cannot understand from your letter whether you wish to see an engine fitted to the purpose of the breakwater1 or for pumping the water from the foundations of the ,exeter ,bridge4 ,please to inform me which of the two purposes you wish to see the engine calculated for1 and about what time you think you shall want it1 and ,i will get one finished suitable to the purpose you intend it for4 ,yours1 c41 ,r4 ,t4 ,,jas4 ,,green1 ,,esq41 ,st4 ,david's ,hill1 ,exeter4 ,n4,b4--,to what extent have ,messrs4 ,fox engaged1 and what parts of the work do they perform8 ,i think more good might be done by loading1 carrying1 and discharging1 than by quarrying only4 ,trevithick was equally ready with the application of steam-power either for pumping of water or for boring and removing rock4 ,the use of chisels and rock-breakers in the ,thames in #ahjcd had prepared the way for the more perfect engine for boring1 lifting1 and carrying rock from the quarries to its destination at the ,plymouth ,breakwater in #ahab4e ,footnote #d3 ,see ,stonebreaker of #ahjc1 vol4 i41 p4 #bci4 ,footnote #e3 ,see ,steam-crane1 vol4 i41 pp4 #afb1 #bgd4 ,,sir1 #ajf1 ,,holborn ,,hill1 ,november #bfth1 #ahab4 ,i am in receipt of yours of the #bbnd inst4 ,mr4 ,giddy informs me that ,mr4 ,fox and ,mr4 ,williams are to have #bs4 #f;d4 per ton for making the breakwater at ,plymouth1 and he considers that they can do it for #bs41 which he thought would give them #ej1jjjl4 profit4 ,if you meet those gentlemen1 ,i have to caution you not to ,,learn ,,them anything until you make a bargain1 as ,i know ,mr4 ,williams will endeavour to learn all he can and then you may go whistle4 ,if #f;d4 per ton will give #ej1jjjl4 profit1 a halfpenny per ton would give upwards of #djjjl4 ,would they agree to give you that for your labour only8 ,however1 this will depend in a great measure on the time it will take in doing4 ,if it takes eight years it would be #ejjl4 a year for you 7according to ,mr4 ,giddy's calculation74 ,your well-wisher1 ,,henry ,,harvey4 ,,mr4 ,,rd4 ,,trevithick1 ,camborne4 ,mr4 ,harvey knew ,trevithick's weakness in money matters4 ,rennie had been employed to report on the proposed ,plymouth ,breakwater1 and in #ahaa was desired by ,lord ,melville1 the head of the ,admiralty1 to proceed with the work4 ,the price paid in #ahab for taking and depositing rubble in the breakwater was #bs4 #i;d4 per ton2 it was afterwards reduced to #as4 per ton4 ,a piece of ground was purchased from the ,duke of ,bedford at ,oreston1 up the ,catwater1 containing #be acres of limestone1 well adapted for the purposes of the work2 and steps were taken to open out the quarry1 to lay down railways to the wharves1 to erect cranes4#f ,the idea of the plan to be followed in conveying stone with greater economy and dispatch than was contemplated by ,rennie1 originated with ,trevithick1 while the former received the credit and the pay1 as he before had done with the steam-dredger4 ,footnote #f3 ',lives of the ,engineers1' by ,smiles1 vol4 ii41 p4 #bfj4 ,rough draft4 ,,mr4 ,,fox ,jun41 ,,camborne1 ,january #bith1 #ahac4 ,sir1--,since ,i was at ,roskrow ,i have been making trial on boring lumps of ,plymouth limestone at ,hayle ,foundry1 and find that ,i can bore holes five times as fast with a borer turned round than by a blow or jumping-down in the usual way1 and the edge of the boring bit was scarcely worn or injured by grinding against the stone1 as might have been expected4 ,i think the engine that is preparing for this purpose will bore ten holes of #b-a_/b inches in diameter #d feet deep per hour4 ,now suppose the engine to stand on the top of the cliff1 or on any level surface1 and a row of holes bored1 #d feet in from the edge of the cliff1 #d feet deep1 and about #ab inches from hole to hole for the width of the piece to be brought down at one time1 and wedges driven into the holes to split the rock in the same way as they cleave moorstone1 only instead of holes #d inches deep1 which will cleave a moorstone rock #aj feet deep when the holes are #ad or #ae inches apart1 the holes in limestone must go as deep as you intend to cleave out each stope1 otherwise the rock will cleave in an oblique direction1 because detached moorstone rocks have nothing to hold them at the bottom1 and split down the whole depth of the rock4 ,in carrying down a large piece of solid ground the bottom will always be fast1 therefore unless it is wedged hard at the bottom of the hole the stope cannot be carried down square4 ,in a hole #b-a_/b inches diameter and #d feet deep put in two pieces of iron1 one on each side of the hole1 having a rounded back1 then put a wedge between the two pieces1 which might be made thus1 if required to wedge tighter at the bottom of the hole than at the top4 ,illustration ,if this plan answers1 the whole of the stones would be fit for service1 even for building1 and would all be nearly of the same size and figure4 ,each piece would be easily removed from the spot by an engine on a carriage working a crane1 which would place them into the ship's hold at once4 ,it would all stand on a plain surface1 and might be had in one1 two1 three1 or four tons in a stone1 as might best suit the purpose1 which would make the work from beginning to end one uniform piece4 ,steam machinery would accomplish more than nine-tenths of all the work1 besides saving the expense of all the powder4 ,i find that limestone will split much easier than moorstone1 and ,i think that a very great saving in expense and time may be made if the plan is adopted4 ,please to think of these hints and write me when and where ,i may see you to consult on the best method of making the tools for this purpose before ,i set the workmen to make them4 ,any day will suit me1 except ,monday1 the #hth of ,february4 ,the sooner the better1 as ,i cannot set to work to make the tools until we have arranged the plan4 ,i am1 ,sir1 ,your humble servant1 ,,rd4 ,t4 ,the successful completion of the ,mont ,cenis ,tunnel in #ahga was mainly due to an ingenious application of combined mechanical force to boring tools1 before limited to man's strength2 but the applied principle existed sixty years ago1 and though not so perfect in detail1 yet more comprehensive4 ,trevithick's high-pressure steam boring engine enabled him to penetrate the rock five times as fast as the quarryman's power4 ,ten holes1 #b-a_/b inches in diameter1 #d feet deep1 could be bored in an hour1 and he sagaciously suggested that in quarrying the limestone for the breakwater1 a row of holes should be bored by his engine #d feet in from the face of the rock1 #b-a_/b inches in diameter1 #d feet deep1 and #ab inches apart2 and by dropping into each hole two half-round pieces of iron1 to be driven asunder by a steel wedge1 large blocks would be forced off without the use of gunpowder4 ,the high-pressure steam-puffer having bored the stone1 moved itself toward the broken mass1 lifted it into waggons1 and again changing its powers from steam-crane to steam-locomotive1 conveyed it to the port1 and lifted it into the ship's hold4 ,the whole operation was thus aptly described by the inventor1 who then counted on contracting for the breakwater work3--,steam machinery will accomplish more than nine-tenths of all the work1 besides saving the expense of all the gunpowder4 ,rough draft4 ,,mr4 ,,robert ,,fox1 ,jun41 ,,camborne1 ,february #dth1 #ahac4 ,sir1--,since ,i was with you at ,falmouth ,i have made a trial of boring limestone1 and find that the men will bore a hole #a-a_/b inch in diameter #a inch deep in every minute1 with a weight of #ejj lbs4 on the bit4 ,i had no lump more than #ab inches deep2 but to that depth ,i found that having a flat stem to the bit of the same width as the diameter of the hole1 twisted like a screw1 completely discharged the powdered limestone from the bottom of the hole without the least inconvenience4 ,from the time the two men were employed boring a hole #ab inches deep1 ,i am convinced to a certainty that the engine at ,hayle will bore as many holes in one day as will be sufficient to split above #ajj tons of limestone1 and would draw that #ajj tons of stone from the spot and put them into the ship's hold in one other day4 ,the engine would burn in two days #ae bushels of coal1 four men would be sufficient to attend on the engine1 cleave the stone1 and put it into the ship's hold4 ,i think it would not amount to above #i;d4 per ton1 every expense included1 but say #as41 which ,i am certain it will not amount to4 ,perhaps it may not be amiss to withhold the method of executing this work until the partners have more fully arranged with me the agreement as to what ,i was to receive for carrying the plan into execution4 ,i do not wish that anyone but your father should be made acquainted with the plan1 and have no doubt he will have sufficient confidence in the scheme to adopt it4 ,i shall be glad to hear from you soon1 as ,i intend to go to ,padstow in a few days and shall not return under a fortnight4 ,your humble servant1 ,,rd4 ,,trevithick4 ,n4,b4--,i this day received a letter from ,mr4 ,gould1 requesting to know what the expense of an engine and apparatus would be for clearing ,falmouth ,harbour1 which ,i have sent by the post4#g ,footnote #g3 ,see letter1 #dth ,february1 #ahac1 vol4 i41 p4 #bdh4 ,it had been and still is the custom to bore rock either with a long and heavy jumper-chisel1 lifted a foot or two1 and falling by its own weight1 pounding to powder a portion of the rock1 or by the use of a much smaller chisel called a borer1 struck by a hammer4 ,trevithick having made his steam-engine perform those jumper and borer movements1 turned his attention to the improvement of the borer1 and found that a revolving bit was more suitable for drilling limestone than the borer-chisel4 ,the powdered stone was removed from the hole by giving a screw form to the stem of the bit4 ,many years afterwards precisely similar bits for boring wood were patented as new things1 and are still used4 ,within five months of his first communication with the contractors for the ,plymouth ,breakwater he had designed and made an engine to bore1 lift1 and convey to the ship's hold #ej tons of stone daily at less than half the cost ,rennie was then paying for it4 ,rough draft4 ,,sir1 ,,camborne1 ,february #dth1 #ahac4 ,i have your letter of the #cast ,january requesting to know the time in which the engine will be ready for the bridge at ,exeter1 and also about giving an additional power to it4 ,the engine shall be ready in six weeks from the end of ,january1 and shall be capable of lifting the #aj-;inch bucket you have ordered instead of the #i-;inch before proposed1 which was to have delivered #ejj gallons of water #ab feet high per minute2 but now the engine shall be made to lift in the same proportion as a #i-;inch is to a #aj-;inch bucket1 which will be #fag gallons of water per minute instead of #ejj gallons1 as was before agreed on1 and ,i shall charge you accordingly4 ,i observe that you have ordered the pump1 and from the description you give of it1 ,i think it will answer very well4 ,if you wish a perpendicular cylinder instead of a horizontal1 ,i can construct it in that way1 but it will not be so convenient for a portable engine4 ,i have now engines with horizontal cylinders at work above ten years1 and find them answer equally as well as a perpendicular cylinder4 ,i remain1 ,sir1 ,your very humble servant1 ,,richd4 ,,trevithick4 ,,jas4 ,,green1 ,esq41 ,exeter4 ,engineers nowaday are not in the habit of designing and constructing a steam-engine in six weeks1 or willing to alter the agreed form from the horizontal to the vertical without charge4 ,rough draft4 ,mr4 ,robert ,fox1 jun41 informed me the other day that you had the sole direction of the work at ,plymouth4 ,had ,i known it at the time you were at ,scorier ,i should have communicated to you my ideas relating to the application of machinery there2 but until a few days since ,i had an idea that the young ,mr4 ,fox was about to take an active part in the management1 which ,i now find was never his intention1 only he very much wishes to have an experiment tried to see to what extent an engine was capable of performing as against men4 ,an engine is now preparing for that purpose4 ,,sir1 ,,camborne1 ,february #bdth1 #ahac4 ,on my return from ,padstow this evening1 where ,i have been for the last fortnight1 ,i found your letter of the #aath inst4 respecting the getting an apparatus ready for the ,plymouth undertaking4 ,before ,i set about it ,i wish to see you and ,mr4 ,fox1 and will call any day you may appoint4 ,waiting your reply1 ,i remain1 ,sir1 ,your very humble servant1 ,r4 ,,trevithick4 ,,mr4 ,,robert ,,fox1 ,jun41 ,falmouth ,after three months of experimental scheming1 without a thought of keeping his inventions secret1 ,trevithick for a moment became worldly wise1 and asked for a written agreement before sending his locomotive boring engine to the breakwater4 ,rough draft4 ,,mr4 ,,fox1 ,,camborne1 #adth ,march1 #ahad4 ,sir1--,i expect to be called to ,london immediately after the end of this month4 ,the engine with the boring apparatus for ,plymouth remains at ,redruth4 ,i very much wish to see you on that business before ,i leave home1 and would be much obliged by your dropping me a note by post1 saying what day it would be convenient for me to wait on you4 ,r4 ,t4 ,the rock-boring machine was completed1 and reached the breakwater two months after his interview with the ,foxes1 who were prominent in the quarrying work4 ,the engine for ,plymouth will be put to break the ground as soon as ,i can find time to go up there4#h ,it was impossible for any one man1 single-handed1 to make perfect such numerous practical inventions as were undertaken by ,trevithick at that time4 ,his letter of a few months before#i reveals the facility with which he moulded the steam-engine to his requirements4 ,the ploughing engine that ,i sent you a drawing for1 after being used for that purpose1 was to have been sent to ,exeter for pumping water4 ,i have been obliged to take the small portable engine from ,wheal ,alfred ,mine1 and have a new apparatus fitted to it for ,plymouth ,breakwater4 ,a small engine which ,i had at work at a mine ,i have been obliged to send to the farmers for thrashing4 ,messrs4 ,fox would probably require many engines for the ,plymouth ,breakwater1 having engaged with ,government to deliver three million tons of stone2 and to prevent delay1 the boring apparatus was applied to an engine made for another purpose1 while drawings for a new and more suitable engine for boring stone were sent to ,mr4 ,rastrick4 ,footnote #h3 ,trevithick's letter1 ,may #bj1 #ahac1 chap4 xxi4 ,footnote #i3 ,see letter to ,mr4 ,rastrick1 ,january #bf1 #ahac1 chap4 xviii4 ,he engaged that an engine should bore holes to split #ajj tons of limestone a day2 and that on the following day it should1 as a locomotive and steam-crane1 load that quantity in waggons1 convey it from the quarry to the port of shipment1 and then by steam-crane place it in the hold of a vessel4 ,the whole of the work to be done by #aa cwt4 of coal and four men4 ,the gross cost would be #as4 per ton for breaking and removing1 though at that time ,mr4 ,rennie was paying #bs4 #i;d4 a ton1 which in after years was reduced to #as41 just what ,trevithick said was a fair price4 ,while this ready application of the high-pressure steam-engine was going on in ,england1 it had also extended to1 and was coining money in the ,mint at ,lima1 where ,trevithick contemplated going to look after it1 intending to land at ,buenos ,ayres1 and make his way across the continent of ,south ,america and the mountains of the ,cordilleras as best he could1 leaving the home field he had made so fertile to be reaped by others1 and the stone-boring locomotive to be forgotten for many years4 ,rough draft4 ,,sirs1 ,,penzance1 ,december #ith1 #ahae4 ,your very great neglect in not writing4444 ,herland engine will work1 ,i expect1 in about fifteen days4 ,it is a plunger of #cc inches diameter1 #aj-;feet stroke1 with a double packing around the top of the plunger-pole1 in the same way as the steam is turned into the stuffing box of a double engine to exclude the air1 only there is a small tube from the bottom of the boiler to the middle of the stuffing box to prevent the escape of steam4 ,i am sorry to find by ,mr4 ,uville's letter that the ,mint engine does not go well4 ,i wish you had put the fire under the boiler and through the tube1 as ,i desired you to do1 in the usual way of the long boilers2 then you might have made your fire-place as large as you pleased1 which would have answered the purpose and worked with wood just as well as with coal4 ,i always told you that the fire-place in the boiler was large enough for coal1 but not for wood2 also if you found that the cock did not open and shut in proper time1 to make the gear to it work the same as the ,dolcoath puffer whim-engine instead of the circular gear4 ,the boiler is strong enough and large enough to work this engine with #cj lbs4 to the inch1 thirty strokes per minute4 ,i hope to leave ,cornwall for ,lima about the end of this month1 and go by way of ,buenos ,ayres1 and cross over the continent of ,south ,america1 because ,i cannot get any other passage4 ,none of the ,south ,sea whalers will engage to take me to ,lima1 as they say they may touch at ,lima or they may not4 ,unless ,i give them an immense sum they will not engage to drop me there4 ,to be brought back to ,england after a two years' voyage without seeing ,lima would be a very foolish trip4 ,to make a certainty ,i shall take the first ship for ,buenos ,ayres1 preparations for which ,i have already made4 ,this unfinished rough draft was intended for one of the men who had gone to ,lima1 less fruitful in emergency than ,trevithick1 who1 without a moment's hesitation1 would have constructed a fire-place outside the boiler1 when the internal tube fire-place was found to be too small for a wood fire4 ,trevithick's proposing sixty years ago to make his way over the almost unknown track from ,buenos ,ayres1 on the ,atlantic1 to ,lima1 on the ,pacific1 was perhaps characteristic of his daring spirit1 that turned all things to good account2 but he dreamed not that his grandson and namesake would at this time be conducting the steam-horse on the same line of march on the ,central ,argentine ,railway from ,rosario to ,cordoba1 in the ,argentine ,republic4 ,rough draft4 ,,gentlemen1 ,,camborne1 ,august #aith1 #ahac4 ,i received yours at ,bridgenorth of the #aith ,july1 ordering a steam-engine for rolling sugar-cane4 ,i immediately set the founders to work on one for you1 which is to be ready by my return to ,bridgenorth about the end of ,september4 ,i intend to ship it for ,bristol1 and will call on you on my journey down to ,cornwall1 as ,i intend to set it to work at ,bristol for your inspection before it is put on board ship4 ,the price ,i cannot accurately say at present1 as the engine now making is on a new principle2 and as it will be more simple in construction1 ,i hope to be able to render it within the price before stated to you4 ,as it is on a new plan ,i cannot fix the price until ,i know the cost of making4 ,all ,i can say at present is that it shall not exceed what ,i stated to you in my former letter4 ,i remain1 ,sirs1 ,your humble servant1 ,,rd4 ,,trevithick4 ,,messrs4 ,,pinneys ,,and ,,ames1 ,bristol4 ,the engine for the sugar plantations in ,jamaica1 on an improved plan1 was to be constructed in the short space of six weeks1 and if a saving in cost was effected1 the inventor would hand the whole of it to the purchaser4 ,rough draft4 ,,sir1 ,,penzance1 ,,cornwall1 ,march #hth1 #ahaf4 ,i received your favour of the #beth ,january1 but did not answer it in due course1 because ,i was then erecting a very large engine1 which is the first on a new plan4 ,this engine1 which has been at work about a month1 performs exceedingly well4 ,the cost of erection and the consumption of coal are not above one-third of a ,boulton and ,watt's1 to perform the same work4 ,an engine of #d-;horse power will not require a space of more than #e feet high1 #e feet long1 and #c feet #f inches wide4 ,in some instances ,i employ a balanced wheel #e feet in diameter4 ,the water required will be a pint and a half per minute4 ,the coal1 one quarter of a bushel or #ba lbs4 per hour4 ,the price of a machine1 finished and set to work1 #ajj guineas4 ,it does not require either wood or mason work1 but stands independent of every fixture1 and may be set to work in half an hour after being brought on your premises4 ,your obedient servant1 ,,richd4 ,,trevithick4 ,,dr4 ,,moore1 ,m4,d41 ,exeter4 ,a #d-;horse-power portable high-pressure steam-puffer engine cost #ajel41 with internal fire-tube and machinery attached to the boiler1 ready for work in half an hour after lighting the fire1 consumed #ba lbs4 of coal and #aa gallons of water for each hour's work1 at a cost of threepence4 ,the reader's attention has been very imperfectly drawn to the numerous subjects touched on in these remnants of ,trevithick's correspondence between the years #ahjd and #ahaf2 among them may be traced the portable high-pressure steam-engine1 the tubular cylindrical boiler of wrought iron1 the economy of expansive working with steam of #ajj lbs4 on the inch1 but limiting it to #bj lbs4 when not in the charge of experienced workmen1 and testing boilers by water pressure to four times the intended working pressure4 ,the economy of heat in smelting furnaces and in the arated steam-engine were bold means to large results4 ,the cheap #ajjl4 steam-engine of #ahab1 with open-top cylinder and rigid simplicity of gear1 resembling ,newcomen's first atmospheric engine1 was really a high-pressure steam expansive engine1 with the germ of surface condensation1 as ready to convey itself from mine to mine or from farm to farm1 and to join in performing labourer's work1 even to boring and conveying rock by land or sea1 as the most perfect of modern engines2 and yet this unadorned engine1 as seen in the agricultural engine of the following chapter1 followed the excellent mechanism of the double-acting ,kensington model of #agih1 and the still more beautiful engine of the #ahjb patent and ,london locomotive4 ,,chapter ,,xviii4 ,,agricultural ,,engines4 ,the late ,mrs4 ,trevithick said that during the difficulties in ,london in #ahjh and #ahaj1 when ,trevithick was overwhelming himself with new experiments and the cost of patents1 and law expenses1 lawyers and bailiffs took everything worth having from her house1 including account-books1 drawings1 papers1 and models1 which she never saw again4 ,his earlier account-books left in safety in his ,cornish home1 though very disconnected1 give trustworthy traces of his work up to #ahjc4 ,from that time only detached accounts or papers are found until #ahab1 when the unused pages in two old mine account-books of his father served as his letter 7rough-draft7 books2 and judging from their number and style1 his correspondence was most extensive and varied4 ,rough draft4 ,,hayle ,,foundry1 ,february #acth1 #ahab4 ,,to ,,sir ,,christopher ,,hawkins1 ,baronet4 ,sir1--,i now send you1 agreeable to your request1 a plan and description of my patent steam-engine1 which ,i lately erected on your farm for working a thrashing mill4 ,the steam-engine is equal in power to four horses1 having a cylinder of #i inches in diameter4 ,the cylinder1 with a moderate heat in the boiler1 makes thirty strokes in a minute1 and as many revolutions of the fly-wheel1 to every one of which the drum of the thrashing mill 7which is #c feet in diameter7 is turned twelve times4 ,the boiler evaporates #i gallons of water in an hour1 and works six hours without being replenished4 ,the engine requires very little attention--a common labouring man easily regulates it4 ,illustration3 ,,trevithick',s ,,high-,,pressure ,,steam-,,puffer ,,thrashing ,,engine1 #ahab4 ,the expense of your engine of #d-;horse power1 compared with the expense of four horses1 is as follows3-- s4 ,original cost of the steam-engine #hj #j ,building material and rope #aj #j ------ #ij #j ------ ,interest on the above #ijl4 at #e per cent4 #d #aj ,wear and tear at #e per cent4 #d #aj ------ #i #j ------ ,original cost of horse machinery for four horses #fj #j ,interest on the above at #e per cent4 #c #j ------ ,wear and tear at #ae per cent4 #i #j ------ #ab #j ,two bushels or #afd lbs4 of coal will do the work of four horses1 costing #bs4 #f;d4 ,four horses at #es4 each1 gives #bjs4 ,cost of coal1 #bs4 #f;d4 as compared with #bjs4 for horses4 ,i remain1 ,sir1 ,your obedient servant1 ,,richard ,,trevithick4 ,,cornwall1 ,february #bjth1 #ahab4 ,having been requested to witness and report on the effect of steam applied to work a mill for thrashing corn at ,trewithen1 we hereby certify that a fire was lighted under the boiler of the engine five minutes after eight o'clock1 and at twenty-five minutes after nine the thrashing mill began to work1 in which time #a bushel of coal was consumed4 ,that from the time the mill began to work to two minutes after two o'clock1 being four hours and three-quarters1 #aejj sheaves of barley were thrashed clean1 and #a bushel of coal more was consumed4 ,we think there was sufficient steam remaining in the boiler to have thrashed from #ej to #ajj sheaves more barley1 and the water in the boiler was by no means exhausted4 ,we had the satisfaction to observe that a common labourer regulated the thrashing mill1 and in a moment of time made it go faster1 slower1 or entirely to cease working4 ,we approve of the steadiness and the velocity with which the machine worked2 and in every respect we prefer the power of steam1 as here applied1 to that of horses4 7,signed7 ,,matthew ,,roberts1 ,lamellyn4 ,,thomas ,,nankivill1 ,golden4 ,,matthew ,,doble1 ,barthlever4 ,this first high-pressure steam thrashing machine was working on the #acth ,february1 #ahab1 at ,trewithen1 the property of ,sir ,christopher ,hawkins1 as proved by ,trevithick's drawing of the machine1 his account of the work performed1 and the report of the three wise men that the power of steam was preferable to the power of horses4 ,its first cost was less than that of a horse machine2 but to make the calculated amounts come right ,trevithick charged #ae per cent4 for wear and tear on the horse machinery1 and but #e per cent4 on the steam-engine2 overlooking the cost of the horses1 which would have made the outlay for the horses and machinery greater than for the steam-engine4 ,the whole design evidences simplicity and consequent cheapness2 no complication of valves or valve-gear1 no cylinder cover1 parallel motion1 guide-rods1 or air-pump1 with its condenser and injection-water4 ,the #d-;horse engine1 with boiler complete1 cost #ijl4 ,a common labourer worked it1 and as it needed no supply of feed-water during six hours of work1 the cost and attention of supplying feed were avoided4 ,if a supply was required during the day it could be given by a pipe with two taps4 ,this first use of steam in agriculture was immediately followed by ,lord ,dedunstanville of ,tehidy1 ,mr4 ,kendal of ,padstow1 and ,mr4 ,jasper of ,bridgenorth4 ,sir ,charles' request for a more official report signed by disinterested persons brought a reply that the thrashing engine continued to work well4 ,it far exceeds my expectation4 ,i am now building a portable steam-whim1 on the same plan1 to go itself from shaft to shaft4 ,if you should fall in with any ,west ,india planter that stands in want of an engine1 he may see this at work in a month1 which will prove to him the advantage of a portable engine to travel from one plantation to another4 ,the price complete is #ajel4#aj ,footnote #aj3 ,see ,trevithick's letter1 #ajth ,march1 #ahab1 chap1 xx4 ,,dear ,,sir1 ,,argyle ,,street1 #aith ,march1 #ahab4 ,i am sorry it is not convenient for me to advance you the money for ,wheal ,liberty2 adventurers having the dues very low1 ought to furnish the needful4 ,i am very glad you have succeeded with your portable steam-engine1 and am persuaded they will be more and more adopted4 ,i have shown your account of your thrashing by steam1 and ,sir ,john ,sinclair and ,mr4 ---- very highly approve it4 ,sir ,john ,sinclair wished the communication had been made to the ,board of ,agriculture4 ,sir ,john wished me to transmit you the enclosed on coals moved by steam 444 whether you had a plan of this sort1 as they would be very serviceable in passing the friths in ,scotland4 ,he seems to think you ought to advertise your steam-engines for thrashing2 indeed1 ,i think so too4 ,by the enclosed letter1 ,sir ,john ,sinclair wishes you to send him an account of your improved steam-engines4 ,you will be careful in drawing up your letter to ,sir ,john1 because it will probably be read to the ,board of ,agriculture1 and perhaps inserted in their publication4 ,you will begin by acknowledging his letter1 of date 444 respecting the ,american passage boat 444 and your improved small steam-engine4 ,you will give him an account of the saving you have effected at ,dolcoath1 and a certificate of the same by the mining captains2 the engine for thrashing you built for me1 and the work it did1 and the coals it consumed2 the expense of the steam-engines1 and the uses they may be applied to4 ,i remain1 dear ,sir1 ,yours most obediently1 ,c4 ,,hawkins4 ,in #ahab ,trevithick advertised the use and sale of steam-engines1 weighing #ae cwt41 costing #fcl41 for thrashing1 grinding1 sawing1 or other home work2 and also a more powerful engine for the steam-plough1 or the harrow and spade machine for #ajel41 to travel from farm to farm4 ,he wrote to ,sir ,john ,sinclair3#aa-- ,i received from ,sir ,charles ,hawkins a copy of ,dr4 ,logan's letter to you1 also a note from you to ,sir ,charles ,hawkins1 both respecting the driving boats by steam2 respecting the engine for thrashing1 chaff-cutting1 sawing1 c4 ,i am now making one of about two-thirds the size of ,sir ,charles ,hawkins'1 which will be portable on wheels4 ,by placing the engine in the farm-yard1 and passing the rope from the fly-wheel through the barn-door1 or window1 and around the drum on the machine axle1 it may be driven4 ,footnote #aa3 ,see ,trevithick's letter1 #bfth ,march1 #ahab1 chap4 xv4 ,the steam may be raised1 and the engine moved a distance of two miles1 and the thrashing machine at work1 within one hour4 ,the weight1 including engine1 carriage1 and wheels1 will not exceed #ae cwt42 about the weight of an empty one-horse cart4 ,the size is #c feet diameter1 and #f feet high4 ,if you wish to have one of this size sent to the ,board of ,agriculture as a specimen1 the price delivered in ,london will be sixty guineas4 ,this engine differed from that referred to in the drawing of ,sir ,charles ,hawkins1 mainly in the boiler having the fire-place in the fire-tube1 requiring no brickwork1 and having the advantage of portability4 ,it was very like the earlier locomotive boiler1 except that it was placed upright1 as steam-cranes now use boilers1 instead of being horizontal4 ,rough draft4 ,,camborne1 ,,cornwall1 ,april #bfth1 #ahab4 ,,to ,,sir ,,john ,,sinclair4 ,i have your favour of the #dth instant1 informing me that you had sent my letter respecting propelling ships by steam to the ,navy ,board2 and also requesting a drawing and statement of the thrashing engine to be sent to the ,president of the ,board of ,agriculture1 which shall be forwarded immediately4 ,i beg to trouble you with a few wild ideas of mine1 which perhaps may some future day benefit the public1 but at this time remain buried1 for want of encouragement to carry it into execution4 ,the average consumption of coals in large steam-engines is about #hd lbs4 7or one bushel71 to lift #aj1jjj tons of water or earth #a foot high4 ,the average cost of this coal in the kingdom is sixpence4 ,the average of a horse's labour for one day is about #djjj tons lifted #a foot high1 costing about #es4 ,a man's labour for one day is about #ejj tons lifted #a foot high1 costing #cs4 #f;d4 ,i have had repeated trials of the water lifted by coals1 horses1 and men1 proving that where a bushel of coal can be purchased for sixpence1 that sixpence is equal to #bjs4 of horse labour1 and to #cl4 #ajs4 of men's labour4 ,if you calculate a man to lift #ejj tons #a foot high1 it is equal to #ajj tons lifted #e feet high2 a very hard task for a man to perform in a day's work4 ,this calculation proves the great advantage of elemental power over animal power1 which latter ,i believe can in a great part be dispensed with if properly attended to1 especially as we have an inexhaustible quantity of coals4 ,to prove to you that my ideas are not mere ideas1 in general my wild ideas lead to theory1 and theory leads to practice1 and then follows the result1 which sometimes proves of essential service to the public4 ,about six years ago ,i turned my thoughts to this subject1 and made a travelling steam-engine at my own expense to try the experiment4 ,i chained four waggons to the engine1 each loaded with #b-a_/b tons of iron1 besides seventy men riding on the waggons1 making altogether about #be tons1 and drew it on the road from ,merthyr to the ,quaker's-yard 7in ,south ,wales71 a distance of #i-c_/d miles1 at the rate of four miles per hour1 without the assistance of either man or beast1 and then1 without the load1 drove the engine on the road sixteen miles per hour4 ,i thought this experiment would show to the public quite enough to recommend its general use2 but though promising to be of so much consequence1 has so far remained buried1 which discourages me from again trying1 at my own expense1 for the public1 especially when my family call for the whole of my receipts from my mining concerns for their maintenance4 ,it is my opinion that every part of agriculture might be performed by steam2 carrying manure for the land1 ploughing1 harrowing1 sowing1 reaping1 thrashing1 and grinding2 and all by the same machine1 however large the estate4 ,even extensive commons might be tilled and effectually managed by a very few labourers1 without the use of cattle4 ,two men would be sufficient to manage an engine1 capable of performing the work of #ajj horses every twenty-four hours2 requiring no extensive buildings or preparations for labourers or cattle1 and having such immense power in one machine as could perform every part in its proper season1 without trusting to labourers4 ,i think a machine that would be equal to the power of #ajj horses would cost about #ejjl4 ,my labour in invention ,i would readily give to the public1 if by a subscription such a machine could be accomplished and be made useful4 ,it would double the population of this kingdom1 for a great part of man's food now goes to horses1 which would then be dispensed with1 and so prevent importation of corn1 and at a trifling expense make our markets the cheapest in the whole world2 because there are scarcely any coals to be found except in ,england1 where the extreme price1 duty included1 does not exceed #bs4 per bushel4 ,i beg your pardon for having troubled you with such a wild idea1 and so distant from being carried into execution2 but having already made the experiment before stated1 which was carried out in the presence of above #aj1jjj spectators1 who will vouch for the facts1 ,i venture to write to you on the subject1 for the first and only self-moving machine that ever was made to travel on a road1 with #be tons1 at four miles per hour1 and completely manageable by only one man1 ,i think ought not to be dropped without further experiments1 as the main point is already obtained1 which is the power and its management4 ,your most obedient servant1 ,,richard ,,trevithick4 ,the ,board of ,agriculture in #ahab had their attention drawn to the feasibility of using the steam-engine to save agricultural labour and lessen the cost of working land4 ,trevithick's intuitive knowledge told him his application would be in vain1 though an engine was at work proving the saving of horse-power in the item of thrashing corn4 ,i beg to trouble you with a few wild ideas of mine1 which perhaps may some future day benefit the public4 ,a steam-engine could exert as much power by the consumption of #f;d4 worth of coal as could be given by #bjs4 of horse-power1 or by #gjs4 worth of men's power4 ,ideas lead to theory1 theory leads to practice1 then follows the result1 which sometimes proves of essential service to the public4 ,it is my opinion that every part of agriculture might be performed by steam4 ,carrying manure for the land1 ploughing1 harrowing1 sowing1 reaping1 thrashing1 and grinding2 and all by the same machine1 however large the estate4 ,two men would manage an engine capable of performing the work of #ajj horses4 ,such a use of the steam-engine1 judiciously managed1 would double the population of this kingdom1 and make our markets the cheapest in the world2 because ,england is the country best supplied with coal and iron for steam-engines1 and the land now growing food for horses would be available for man4 ,its cost would be #ejjl41 and its power sufficient to propel the largest subsoil ploughs and tormentors2 and had the ,board of ,agriculture supplied such a sum of money as is now ordinarily given by a farmer for a steam-plough1 we should have had in #ahab ploughing1 harrowing1 sowing1 reaping1 c41 by steam4 ,years before1 the same kind of engine had been made to work pumps1 wind coal from shafts1 drive rolling mills1 tilt hammers1 and steamboats1 and convey material from place to place2 and why should not his promise to the farmer be also made good with his increased knowledge derived from eight years of active experience8 ,receiving small encouragement in ,england1 he applied to sugar-cane planters to give his engines a trial in the ,west ,indies4 ,rough draft4 ,,sir ,,charles ,,hawkins1 ,bart41 ,,camborne1 #ast ,may1 #ahab4 ,sir1--,i have your favour of the #bgth ,april1 respecting a steam-engine for your friend for the ,west ,indies1 of the power of ten mules employed at one time4 ,this power we calculate equal to forty mules every twenty-four hours1 as six hours' hard labour is sufficient for one mule for one day4 ,the expense of an engine of this power complete delivered in ,london would be #bjjl4 ,the consumption of coals about #hd lbs41 or one bushel1 to equal the labour of three mules1 or from #ac to #ad bushels of coal every twenty-four hours to perform the full work of forty mules 7or in proportion for a lesser number71 with a waste of about #ae gallons of water per hour1 unless a reservoir was made to receive the steam1 and then to work the same water over again4 ,where water is scarce1 nearly the whole may be saved4 ,you remarked that the rope might slip round the notch in the wheel2 but to prevent any risk of that kind1 ,i apply a small chain instead of the rope1 which works the same as a chain on the barrel of a common thirty-hour clock4 ,the speed of the periphery of the fly-wheel is about eight miles per hour1 which ,i think is nearly double the speed of the mules when at work in the mill4 ,this would reduce the size of the part which carries the chain on the cattle mill to half the diameter of the present walk of the cattle1 which might be done without altering or interfering with the present cattle mills1 and might1 if required1 either work separately or in conjunction with the mules in the same mill at the same time4 ,to inform your friend of the power and effect of such an engine1 ,i prefer his sending some person down to ,cornwall1 to see it tried on some of the cattle mills or whims in the mines4 ,engines that have been sent to the ,west ,indies hitherto have cost nearer #bjjjl42 very large1 heavy1 and complicated machines1 requiring #bejj gallons of water per hour for condensing1 and could only be managed by a professed engineer1 while any common labourer can keep in order and work these engines4 ,if you prefer to send a person with it1 the cost will be about #djs4 per week4 ,i remain1 ,sir1 ,your most obedient servant1 ,,richard ,,trevithick4 ,this letter indirectly points out two long-standing radical errors in engineering phraseology4 ,an early method of describing the value of an engine was by stating the number of pounds it would lift one foot high by the burning a bushel of coal1 called the duty of an engine4 ,trevithick's bushel was #hd lbs41 while other engineers1 under the same term of bushel1 meant various weights1 up to #abj lbs4 ,another form of speaking was the horse-power of an engine2 meaning that a horse could lift a certain number of pounds one foot high in a minute1 and that a steam-engine lifting ten times as much was a #aj-;horse engine2 but1 as ,trevithick points out1 a horse only works at that rate for six hours out of twenty-four1 while the steam-engine works continuously1 performing the work of forty horses1 yet is called a #aj-;horse engine4 ,the high-pressure engine suitable for the ,west ,indies was to be adapted to the existing horse or mule machinery1 that either power might be used4 ,its first cost and expense in working to be much less than that of the ,watt low-pressure steam vacuum engine4 ,rough draft4 ,,sir ,,charles ,,hawkins1 ,bart41 ,,camborne1 ,june #acth1 #ahab4 ,sir1--,yours of the #aeth of last month ,i received1 enclosing a drawing of a sugar-mill from ,mr4 ,trecothick1 which ,i should have answered per return1 but was at that time in treaty for an engine for a sugar-mill with a ,mr4 ,pickwood1 who is in ,st4 ,kitts in the ,west ,indies4 ,the engine is now being erected at ,hayle ,foundry1 of the power of twelve mules at a time1 or equal to forty-eight mules during twenty-four hours4 ,the cost is #bajl4 complete1 with numerous duplicate parts4 ,i hope she will be finished and sent off in a short time4 ,i have now so fully proved the use of those engines1 that ,i have engaged to take this one back if it does not answer their purpose1 and to refund the whole sum if they return the engine to me in working order within four years4 ,this gentleman says1 if this engine answers he shall have two more for his own use1 and four of his friends are waiting to see the result before ordering their engines4 ,the mules that will be turned out of use by ,mr4 ,pickwood's engine will sell for five times the sum the engine will cost him1 exclusive of the wear of mules1 with their keep and drivers1 besides the greater dispatch and pleasantness of working a machine instead of forcing animals in so hot a climate4 ,if your friend wishes an engine of this power and on the same terms1 ,i can get two made and sent to ,london nearly in the same time as one4 ,enclosed ,i send to you a rough sketch of the engine and mill4 ,i am of your opinion1 that ,sir ,john ,sinclair has taken a useless journey by calling on the ,navy ,board1 for nothing experimental will ever be tried or carried into effect except by individuals4 ,if ,i could get an ,act of ,parliament for twenty-one years for only one-tenth part of the saving which ,i could gain over animal power and expense1 ,i have no doubt but that ,i could get money to carry the plan fully into effect for propelling ships1 for travelling with weights on roads1 and doing almost every kind of agricultural labour4 ,but a patent is but for fourteen years1 and open to constant infringement2 for the inventor of general and useful machinery is a target for every mechanic to shoot at1 and unless protected or encouraged by some better plan than a common patent1 will have the whole kingdom to contend with in law1 and most likely receive ruin for his reward1 which has too often been the case4 ,a plan of such magnitude as this promises to be of1 ,i think ought to be carried into effect by subscription1 and as soon as accomplished1 the subscribers to be repaid1 and the invention thrown open for the use of the kingdom at large4 ,i think about #ajjjl4 or #aejjl4 would test the designs4 ,it is expected that ,mr4 ,praed will spend some time in this neighbourhood2 ,i hope ,i shall be able to prove to you and to him the great use of propelling barges by steam4 ,i have a small engine now at foundry1 and would put it on board one of their barges for your inspection4 ,i am very much obliged for your continued favours1 and beg pardon for so often troubling you4 ,i have so fully proved the great advantages resulting from those portable engines1 that ,i very much wish the public to have the full use of them4 ,i remain1 ,sir1 ,your most humble servant1 ,,richard ,,trevithick4 ,a #ab-mule-power engine for ,st4 ,kitts was being erected at ,harvey's foundry at ,hayle2 ,trevithick making himself liable for the whole cost1 in case it should not answer the purpose4 ,the mules thrown out of work by the engine would sell for five times as much as the engine cost1 to say nothing of the saving in wear and tear of drivers and mules1 and the unpleasantness of driving a mule in hot weather as compared with a machine4 ,if an ,act of ,parliament would give him one-tenth of the saving he could effect during twenty-one years1 a company might be formed for carrying into full effect his plans for propelling ships1 travelling with weights on roads1 and performing almost every kind of agricultural labour1 while a patent for fourteen years was open to constant infringement1 and the inventor of useful machinery was a target for every mechanic to shoot at1 had law suits with the kingdom at large1 and ultimate ruin1 as a reward for his labours4 ,inventions of such general application1 when fairly established1 should be thrown open to the public1 ,government paying the inventors their expenses1 and reasonable reward for their time4 ,rough draft4 ,,mr4 ,,pickwood1 ,,cornwall1 ,,camborne1 #agth ,june1 #ahab4 ,sir1--,yours of the #agth ,april ,i received about twenty days since1 and from that time to the present have been in treaty with ,messrs4 ,plummer1 ,barham1 and ,co41 for your engine4 ,we have now closed for an engine complete1 of the power of twelve mules at a time1 with suitable duplicates1 chains1 c41 for #bajl4 ,i very much wish for your engine to be set to work by your own workmen1 to show the planters the simplicity and easy management of the machine1 and also save the expense of an engineer1 which will tend to promote their use4 ,the engine will be set to work before it is sent off1 and every possible care taken to execute it in the most perfect order4 ,from the experience ,i have had with common labourers keeping these engines in order1 since ,i wrote to you1 ,i have no doubt you will get on satisfactorily4 ,i hope to get the engine ready in five or six weeks1 but ,i fear there will be loss of time in shipping it4 ,you may rest assured that ,i will spare no time or attention to promote the performance of this engine4 ,i am so far satisfied with the probability of its fully answering your purpose that ,i voluntarily offered ,messrs4 ,plummer1 ,barham1 and ,co41 that if you return it to me for working repairs within four years1 ,i will refund the whole of the sum ,i am to receive for it4 ,i will take particular care to mark every part and send you a full description4 ,enclosed ,i send you a sketch of the engine attached to a sugar-mill4 ,please write to me by return of the packet2 it may be in time1 before the engine is shipped1 to alter1 or send you such things as ,i may not be acquainted with4 ,i shall be glad to know the number of yards your mules travel in an hour when going at what you call a fair speed1 in the mill1 and also what number of rounds you wish the centre roll to make in an hour when worked by the engine4 ,i remain1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,r4 ,w4 ,,pickwood1 ,esq41 ,st4 ,kitts1 ,west ,indies4 ,these are not the remarks of an uncertain schemer2 every sentence having the impress of the ability and fixed intention of perfecting the work1 and the belief that the simplicity of the engine would enable a common labourer to use it4 ,rough draft4 ,,sir ,,ch4 ,,hawkins1 ,bart41 ,,camborne1 #eth ,july1 #ahab4 ,sir1--,if your friend ,mr4 ,trecothick intends to have a sugar-mill engine immediately finished and sent out with the one ,i am now making for ,mr4 ,pickwood1 he ought not to lose any time in giving his orders4 ,i have made inquiry at ,falmouth about sending out ,mr4 ,pickwood's engine for ,st4 ,kitts on board a packet1 which would save much time1 but ,i fear it cannot be granted unless application is made by some person of note to the ,post ,office in ,london4 ,mr4 ,banfield of ,falmouth told me that if application was made to send out a model as a trial1 he had no doubt but it would be granted4 ,this experiment with the portable engine that will travel from one plantation to another and work without condensing water1 is certainly of the greatest consequence to the planters1 and as the whole weight will not exceed #a-c_/d ton1 ,i should hope that the ,commissioners at the ,post ,office will grant this request4 ,i am sorry to trouble you so often about my business1 but ,i beg the favour of your goodness to inform me through what channel ,i ought to make this application4 ,i remain1 ,sir1 ,your most obedient humble servant1 ,,rd4 ,,trevithick4 ,this experiment with the #a-c_/d ton portable engine to travel from one plantation to another1 needing no condensing water1 was certainly of the greatest consequence to the planters in the ,west ,indies1 and should have been of equal importance to the people in ,england4 ,judging from the weight and cost1 as compared with agricultural engines of the present day1 ,trevithick was nearer the mark then than we are now2 its working without condensing water the engineers of that day believed to be impracticable1 a fundamental error which greatly retarded the use of the high-pressure steam-engine4 ,the providing sufficient condensing water was often a most serious item of cost1 and as water mains were not in use1 a deep well was a necessary part of a steam vacuum engine4 ,rough draft4 ,,gentlemen1 ,,cornwall1 ,,camborne1 ,october #afth1 #ahab4 ,yours of the #cjth of ,september ,i found at my house on my return yesterday from a journey4 ,i am sorry to inform you that ,mr4 ,pickwood's engine is not ready4 ,near three months ago ,i set my smiths and boiler-makers to work to complete an engine for ,mr4 ,pickwood1 which parts were finished five or six weeks ago4 ,the other parts of the engine1 which were to have been made of cast iron1 were ordered and commenced at a foundry in this county1 belonging to ,blewett1 ,harvey1 and ,vivian1 and would have been finished and the engine shipped long since had not these partners in the iron foundry quarrelled with each other1 and the ,lord ,chancellor has laid an injunction and set idle their foundry4 ,i have since ordered the castings to be made at a foundry at ,bridgenorth1 in ,shropshire1 belonging to ,hazeldine1 ,rastrick1 and ,co41 who will complete the engine and send it to you in about two months1 at which time ,i intend to be in town to set it to work before it is shipped for the ,west ,indies4 ,i remain1 ,gentlemen1 ,your very humble servant1 ,,richd4 ,,trevithick4 ,,messrs4 ,,plummer1 ,,barham1 ,,and ,,co41 ,london4 ,p4,s4--,immediately on my receiving your order to prepare an engine for ,mr4 ,pickwood ,i wrote to inform him that ,i had begun it1 and enclosed a drawing of the engine with the method of connecting the engine to the cattle-mills1 and requested he would remit to me his remarks on it1 which ,i received by the last packet1 from which it appears for the best that the engine is not in a forward state1 because the parts would not have been so suitable to the purpose as they will now be4 ,fortune was against ,trevithick4 ,a difficulty between his brother-in-law ,harvey1 and his old partner ,vivian1 with ,blewett1 retarded the completion of the engine2 and the castings so anxiously waited for were ordered from ,hazeldine and ,rastrick4 ,the wrought-iron work was made by the old smiths in his neighbourhood1 who had long been in the habit of hammering his schemes into shape4 ,this patchwork way of constructing engines made success much more difficult4 ,trevithick often laughed heartily at the following incident which occurred during this quarrel at ,harvey's works3--,blewett sent a handsome silver teapot to ,miss ,betsy ,harvey1 who kept her brother's house1 called ,foundry ,house4 ,trevithick was sitting with them when the box was brought in and opened4 ,mr4 ,henry ,harvey was indignant at ,mr4 ,blewett sending a bribe or make-peace to his sister1 and threw the silver teapot under the fire-place4 ,trevithick1 however1 quietly picked it up1 pointed out the dinge it had received1 wrapped his pocket handkerchief around it1 and saying1 if it causes bad feeling here it will do for ,jane1 marched away home with the pot4 ,the writer drank tea from it recently1 and also laughed at the dinge4 ,the following was written to ,mr4 ,rastrick in ,december1 #ahab3ab-- ,i have been waiting your answer to my last1 and especially that part respecting the ,west ,india engine1 as there is a large field there for engines of this kind4 ,i have received an order for a thrashing engine for ,lord de ,dunstanville of ,tehidy1 and as ,i wish those thrashing engines to be known through the country1 ,i intend to take one of the engines ordered for ,padstow and send it to ,tehidy2 one of the ,padstow farmers can wait until you make another for him2 therefore ,i would thank you to send the first finished by ship from ,bristol for ,portreath or ,hayle4 ,send a drum with everything complete1 of which you are a better judge than ,i2 probably about #c feet in diameter and #c-a_/b feet long will be sufficient4 ,there must be a fly-wheel1 with a notch to carry the rope1 and also a small notch wheel on the drum-axle4 ,i think #f-a_/b feet diameter for the fly and #i-a_/b inches diameter for the small wheel1 will give speed enough to the drum4 ,mind to cast a lump or screw on a balance of about #a cwt4 on one side of the wheel4 ,there must be two stands on the boiler1 and a crank-axle or otherwise a crank-pin in the fly-wheel1 whichever you please2 with a shaft #c feet long with a carriage4 ,the engine to stand in a room under the turn-about1 #g-a_/b feet high1 #g feet wide1 and #ag feet long4 ,the fly-wheel will stand across the narrow way of the room4 ,the rope will go up through the floor and the drum be shifted by a screw1 horizontally on the barn floor1 so as to tighten the rope4 ,i shall put down the top of the boiler level with the surface1 with an arched way to the fire and ash-pit underground to prevent the chance of fire1 which the farmers are very much afraid of4 ,footnote #ab3 ,see rough draft1 ,trevithick's letter1 #gth ,december1 #ahab1 chap4 xvii4 ,i send you a sketch showing how it is to stand4 ,i do not bind you to the size of the drum or wheels1 only the room that the fly-wheel works in is but #g feet wide4 ,put the engine and drum for ,lord de ,dunstanville out of hand neat and well1 as it will be well paid for1 and make the stands1 c41 in your own way4 ,this description of ,lord ,dedunstanville's thrashing machine illustrates the drawing of that supplied to ,sir ,charles ,hawkins4 ,rough draft4 ,,mr4 ,,rastrick1 ,,camborne1 ,january #bfth1 #ahac4 ,sir1--,i have your favour of the #ajth inst41 in which you do not state the time when you expect ,i shall have either of the engines that you are executing4 ,as so much time has elapsed since the orders were given1 the persons that ordered them are quite impotent4 ,the ploughing engine that ,i sent you a drawing for1 after being tried for that purpose1 was to have been sent to ,exeter for pumping water out of the foundations of a new bridge2 but as they intend to begin their work at the bridge before the end of ,march1 the engine must be there before that time1 or they will erect horse machines and not use the engine4 ,i have therefore been obliged to send the small boiler that ,i had for that purpose to ,hayle ,foundry1 and get the castings made there for this engine to get it in time to prevent losing the order4 ,i have also been obliged to take the small portable engine from ,wheal ,alfred ,mine and have new apparatus fitted to it1 to apply this engine for ,plymouth ,breakwater4 ,a small engine1 from the same patterns as ,sir ,charles ,hawkins' thrashing engine1 which ,i had at work in a mine1 ,i have been obliged to send to one of the farmers at ,padstow for thrashing1 instead of one of those engines that ,i ordered from you4 ,i expect that the people who ordered the engine for the ,west ,indies are also tired of waiting4 ,i have two other applications for engines for the ,west ,indies1 and the ,messrs4 ,fox will want a great many engines of that size for the ,plymouth ,breakwater4 ,they are to provide machinery1 with every other expense1 and ,i am to have a certain proportion of what ,i can save over what it now costs them to do it by manual labour4 ,i think ,i have made a very good bargain1 for if the plan succeeds ,i shall get a great deal of money1 and if it fails ,i shall lose nothing4 ,they have engaged with the ,government to deliver #c1jjj1jjj tons1 for which they have a very good price1 even if it was to be done by men's labour4 ,i hope ,i shall get the engine soon on the spot1 and will then let you know the result4 ,as the boiler that was intended for the ploughing engine is to be sent to ,exeter1 ,i wish you to finish that engine with boiler1 wheels1 and everything complete for ploughing and thrashing1 as shown in the drawing1 unless you can improve on it4 ,there is no doubt about the wheels turning around as you suppose1 for when that engine in ,wales travelled on the tramroad1 which was very smooth1 yet all the power of the engine could not slip around the wheels when the engine was chained to a post for that particular experiment4 ,that new engine you saw near the seaside with me is now lifting forty millions #a foot high with #a bushel of coal1 which is very nearly double the duty that is done by any other engine in the county4 ,a few days since ,i altered a #fd-;inch cylinder engine at ,wheal ,alfred to the same plan1 and ,i think she will do equally as much duty4 ,i have a notice to attend a mine meeting to erect a new engine equal in power to a #fc-;inch cylinder single1 which ,i hope to be able to send to you for4 ,i have also an appointment to meet some gentlemen at ,swansea1 to erect two engines for them1 one to lift water1 the other coal1 which you will hear more about1 ,i expect1 soon4 ,if ,i can spare a few days when at ,swansea1 ,i will call to see you at ,bridgenorth4 ,i have not seen ,mr4 ,richard since you left1 but will call on him in a few days and do as you request4 ,if you think the fly-wheel is not sufficiently heavy for his engine1 add half a ton more to the ring4 ,if you cannot finish all these engines at the same time1 ,i would rather the smaller ones should be finished first and ,mr4 ,richards' stand a little1 because if his engine was now ready he would not pull down his thrashing machine until he had nearly thrashed all his corn1 and the machine now stands on the spot where the mill is to be erected4 ,if ,i call on you from ,swansea ,i think ,i shall be able to show you a new idea1 which ,i think will1 if carried into practice1 be of immense value4 ,please to write to me and say particularly how you are getting on1 and when you are likely to finish the engines ordered4 ,r4 ,t4 ,trevithick had sent a drawing of a ploughing engine to ,rastrick at ,bridgenorth1 that the castings might be made1 while he himself was having the boiler and wrought-iron work constructed in ,cornwall4 ,the engine had been ordered as a portable pumping engine1 for removing water from the foundation of a bridge at ,exeter2 but before sending it to its destination1 he had arranged to plough with it1 as a means of perfecting the plans and drawings for a more suitable ploughing engine then in construction1 to be fitted with boiler1 wheels1 and everything complete for ploughing and thrashing1 as shown in the drawing4 ,the friction of the wheels on the ground would be greater than the power of the engine2 therefore they would not slip when the full power was applied to draw a plough any more than the ,welsh engine1 the wheels of which did not slip though resting on smooth iron4 ,one of his small engines1 which had been at work in a mine1 was sent as a thrashing engine to ,padstow4 ,it is evident that1 having given a portion of his attention for a year or two to the question of steam agriculture1 he had so far progressed in #ahac as to construct thrashing machines1 portable agricultural engines1 and steam-ploughs to be moved by wheels as in locomotives2 reaping1 sowing1 and other work1 was also in future to be the work of the steam-engine4 ,a drawing by ,trevithick--having as usual neither name1 date1 nor scale1 nor writing of any kind1 but the watermark in the paper is #ahac--;illustrates his ideas expressed to ,sir ,charles ,sinclair in #ahab3--;,it is my opinion that every part of agriculture might be performed by steam4 ,the thrashing and grinding engines were at work1 and the tormenting harrowing engine was probably designed for bringing under steam cultivation the extensive commons referred to4 ,in those days1 before the practice of underground drainage1 the surface of cultivated land was thrown into furrows1 or a series of small hills and vales1 the latter acting as the surface drain for carrying off the water4 ,suppose the first step in cultivating a common to be the breaking of the soil1 and throwing it into uniform lines of rise and fall that facilitated drainage without inconveniencing the tillage1 what better machine could have been devised than ,trevithick's8 ,a combination of the modern tormentor and harrow loosened the ground to the required depth1 which was then1 by a revolving wheel with spades1 thrown on one side1 resulting in uniform lines of ridges and hollows4 ,the steam-shoveller was removed1 or the tormentor irons raised1 when only the harrow was required4 ,the absence of the ordinary shafts at the front end of the framing indicates that the spade-tormentor was not to be drawn by horses1 but whether by a locomotive or by a fixed engine is not self-evident4 ,illustration3 ,,trevithick',s ,,steam ,,spade-,,tormentor1 #ahac4 ,rough draft4 ,,mr4 ,,kendal1 ,,camborne1 ,january #bfth1 #ahac4 ,sir1--,i have yours of the #agth inst4 ,the thrashing machine engine is ready for you1 and shall be sent up immediately4 ,i wish you to get about #ajj fire bricks1 #bjj common bricks1 #bj loads of stone1 and #bj bushels of lime4 ,the house will get finished while ,i am fixing the engine4 ,about #aejj or #afjj weight of iron for your engine has been sent to the ,blue ,hills ,mine1 ,st4 ,agness4 ,i wish you could send down your cart to fetch it from there to ,padstow4 ,there is no part of these castings but may be easily conveyed in a common butt or cart4 ,when you have the stone1 brick1 and lime ready1 and a cart to send to ,st4 ,agness for the castings1 please to write me1 and ,i will come to ,padstow at the same time with them1 and finish the engine4 ,the sooner you get ready the better1 as ,i expect to have an engagement in about four weeks' time1 that would prevent my coming to ,padstow for some time2 therefore ,i wish to get your engine finished before that time4 ,please to write me as early as possible1 and let me know when you will be ready for me1 and what day ,i shall meet your cart at ,st4 ,agness for the castings4 ,your obedient servant1 ,,richard ,,trevithick4 ,real inventors hesitate not to erect their own engines1 lend a hand in building the house1 walk to the scene of action1 or take a lift in a cart2 and by such steps was the gift of genius moulded to the wants of daily life2 while the modern engineer of eminence1 living in large cities1 knows little of the minuti of his work1 or even of the working mechanics on whose skill the success of his ideas is dependent4 ,in #ahae1 ,mr4 ,kendal1 the proctor of ,padstow1 sent for me to repair his steam-engine4 ,to prevent the old disputes in collecting his corn tithes1 he had at work one of ,captain ,trevithick's steam thrashing machines4 ,the small farmers sent their corn produce to him to be thrashed2 the grain was measured1 the tenth taken out1 the remainder returned to the farmer4 ,the three-way cock1 which worked the engine1 was joined in its shell2 on freeing it the engine continued to work very well4#ac ,footnote #ac3 ,captain ,samuel ,grote's recollections1 #aheh4 ,in #ahah ,i put a new four-way cock to a thrashing engine that ,captain ,trevithick had made for ,mr4 ,kendal1 of ,padstow1 who was the receiver of tithe corn4 ,the boiler was a tube of wrought iron1 about #d feet in diameter and #f feet long1 standing on its end4 ,the cylinder was fixed in the top of the boiler2 an upright from the top of the cylinder supported the fly-wheel shaft2 a connecting rod from the crank-pin in the fly-wheel was fastened to a joint-pin in the piston4 ,the cylinder had no cover4 ,the four-way cock was worked by an excentric on the shaft1 moving a lever1 which was kept in contact with the excentric by a spring4#ad ,footnote #ad3 ,recollections of ,captain ,h4 ,a4 ,artha1 ,penzance1 #ahfh4 ,about #ahbd ,i worked in ,binner ,downs ,mine one of ,captain ,trevithick's puffer whim-engines4 ,the boiler was cylindrical1 made of wrought iron4 ,it stood on its end1 with the fire under it1 and brick flues around it4 ,the cylinder was let down into the top of the boiler4 ,a four-way cock near the top of the cylinder turned the steam on and off4 ,the fly-wheel and its shaft were fixed just over the cylinder4 ,a lever and rod worked the four-way cock and feed-pole4 ,the waste steam puffed through a launder into the feed-cistern4 ,the cylinder was about #ab inches in diameter1 with a #c-;feet stroke4#ae ,footnote #ae3 ,recollections of ,henry ,vivian1 ,harvey and ,co4's ,works1 #ahfi4 ,mr4 ,kendal's steam thrashing machine remained at work at least six years1 during which time the only apparent repair was the four-way cock1 worked by an excentric1 which1 if neglected1 was apt to stick fast in its shell4 ,one of the puffer-whims erected about this time was similar to the thrashing engine for ,padstow1 differing from the earlier one made for ,sir ,c4 ,hawkins1 in having a portable boiler so arranged that if necessary it could be easily placed on wheels4 ,rough draft4 ,,sir1 ,,camborne1 ,march #aeth1 #ahac4 ,i have your favour of the #aath inst4 respecting a steam-engine for thrashing4 ,i have made several1 all of which answer the purpose exceedingly well4 ,they are made on a very simple construction so as to be free from repairs1 and are kept in order and worked by the farm labourers1 who never before saw a steam-engine4 ,the first ,i made on this plan was for ,sir ,christopher ,hawkins1 who resides at this time in ,argyll ,street1 ,oxford ,street1 ,london4 ,if you call on him1 he1 ,i doubt not1 would give you every information you require respecting its performance4 ,this was a fixed engine1 because it was only required to work on one farm4 ,it has been at work nearly eighteen months1 and has not cost anything in repairs1 nor any assistance but from the labourer who puts in the corn2 he only gives three or four minutes every hour to put on a little coal4 ,a few pails of water1 put into the furnace in the morning1 is sufficient for a day's work4 ,they have at different times tried what duty the engine would perform with a given quantity of coal1 and found that two ,cornish bushels1 weighing #afh lbs41 would get up steam and thrash #aejj sheaves of wheat in about six hours4 ,before this engine was erected1 they usually thrashed #ejj sheaves1 with three heavy cart-horses for a day's work4 ,i cannot say exactly the measurement of the corn that it thrashed1 but it was considerably above #fj winchesters of wheat with #afh lbs4 of coal2 not a halfpenny in coal for each winchester of wheat4 ,the engines that ,i have since erected have performed the same duty4 ,the horse machinery is thrown out of use1 but the same drum is turned by the engine4 ,a fixed engine of this power ,i would deliver to you in ,london for #ajj guineas2 it would cost you about #ael4 more to fix the furnace in brickwork4 ,a portable engine costs #afj guineas1 but it would cost nothing in erecting1 as it will be sent with chimney and every thing complete on its own wheels 7the drum1 c41 excepted71 which you may convey with one horse from farm to farm as easy as a common cart4 ,if you have not sufficient work for it you can lend it to your neighbours4 ,the last engine ,i erected was about three weeks since1 for a farmer that kept four horses and two drivers4 ,the parts of the horse machine thrown out of use1 together with the four horses1 sold for more money than he gave me for the engine1 exclusive of #dl4 per week that it cost him in horse keep and drivers to thrash #cjjj sheaves per week4 ,now the engine performs more than double that work1 and does not cost above #ajs4 per week2 and the labourer in the barn does double the work he did before for the same money4 ,if you wish the same engine to have sufficient power to turn one pair of mill-stones1 the cost will be #bbj guineas4 ,r4 ,,trevithick4 ,,mr4 ,j4 ,,rawlings1 ,strood1 ,kent4 ,,camborne1 #bhth ,august1 #ahac4 ,,messrs4 ,,hazeldine1 ,,rastrick1 ,,and ,,co41 ,gentlemen1--,lord ,dedunstanville's engine thrashed yesterday #aejj sheaves in #ij minutes with #dj lbs4 of coal4 ,,rd4 ,,trevithick4 ,the first steam thrashing engine was worked by a labouring man for eighteen months1 without needing repair1 or even attention beyond three or four minutes each hour to put on a little coal4 ,necessary stoppages for various purposes caused a day's work to be no more than the engine could perform in half a day4 ,no additional feed-water was required during an ordinary day's work to thrash #aejj sheaves of wheat with #afh lbs4 of coal1 while on a special occasion that quantity was thrashed in an hour and a half1 consuming only #dj lbs4 of coal4 ,three horses during three days were required to do the same amount of work4 ,a farmer sold his horses used in thrashing for more money than his engine cost1 which did twice as much work at a reduced expenditure1 and also saved the feed of the horses4 ,such an engine could be delivered in ,london for #ajj guineas1 while a portable engine on wheels with a differently constructed boiler1 requiring no mason work1 would cost #afj guineas4 ,rough draft4 ,,gentlemen1 ,,cornwall1 ,,camborne1 #aith ,august1 #ahac4 ,i have your favour of the #ith ,august1 respecting steam-engines for ,st4 ,kitts4 ,i fear it will not be possible to get an engine ready by the #ast of ,november4 ,as you say the gentleman that is about to take them out is a clever man1 and likely to promote the use of them1 ,i will make immediate inquiry1 and1 if possible1 will get one ready1 of which ,i will inform you in a short time4 ,i very much wish that every person who intends to employ a steam-engine of mine would first examine the engine1 and be satisfied with the construction before giving an order1 for which reason ,i must request you to send your friend down to ,messrs4 ,hazeldine and ,rastrick's foundry1 ,bridgenorth1 ,shropshire1 where he may see the portable steam-engine that was made for ,mr4 ,pickwood1 which the founders will set to work for his inspection in half an hour after his arrival4 ,as this gentleman has a taste for machines1 and wishes to make himself fully acquainted with the principle and use of the steam-engine1 he will be much gratified with the sight of this curious machine and with the information he will receive from the founders1 which will be essentially necessary to him before leaving ,england4 ,i am extremely disappointed that this engine was not forwarded to ,mr4 ,pickwood1 as ,i find from his letter that he has an exceedingly clever and active mind1 and is a very fit person to take the management of introducing a machine into a new country4 ,this engine is engaged by a ,spanish gentleman1 who is going to take out nine of my engines with him to ,lima1 in ,south ,america1 in about six weeks4 ,i remain1 your obedient servant1 ,,richd4 ,,trevithick4 ,,messrs4 ,,plummer1 ,,barham1 ,,and ,,co41 ,london4 ,n4,b4--,if your friend goes to ,bridgenorth1 let him show this letter to the founders4 ,the engine1 intended for the ,west ,indies1 so pleased ,mr4 ,uville1 that he begged to have it made over to him for ,south ,america1 where it worked the machinery for rolling gold and silver in the ,mint at ,lima4 ,about #ahae1 while erecting a high-pressure pole-engine at ,legassack for ,mr4 ,trevithick1 and doing some repairs to ,mr4 ,kendal's thrashing engine1 a ,creole1 ,i think called ,nash1 brought a note from ,captain ,trevithick1 stating that the bearer was anxious to be taught to erect and work the portable engines for ,jamaica4 ,sir ,rose ,price1 who had property in the ,west ,indies1 had sent him to ,mr4 ,trevithick for that purpose4#af ,footnote #af3 ,recollections of ,captain ,h4 ,a4 ,artha1 ,penzance1 #ahfi4 ,it is therefore probable that some of ,trevithick's engines reached ,jamaica4 ,sir ,rose ,price was well known to ,lord ,dedunstanville and ,sir ,charles ,hawkins1 and living near them1 saw the engines at work and their fitness for his property in ,jamaica4 ,lord ,dedunstanville's engine of #ahab was sold as old iron to ,messrs4 ,harvey and ,co4 not long before #ahdc4 ,having remained for some time on the old-scrap heap1 it was in that year again worked to drive machinery4 ,instead of the original rope-driver on the fly-wheel1 a chain was used1 the links of which caught on projecting pins on the driving wheel4 ,in that form it continued to work until #ahec1 before which it was frequently seen by the writer prior to its removal to make room for a more powerful engine4 ,what greater proof could be given of the fitness of design of this early engine1 than its long life of forty years under such rough treatment1 and the facility with which it was applied to different uses4 ,mr4 ,bickle1 who1 from recollection1 had made a sketch of this engine before the writer had found ,trevithick's sketch1 says that after the engine had ceased to work1 the boiler was turned to account in heating tar in the ship-builder's yard4 ,in #ahed ,i saw working in a shed at ,carnsew1 in the ship-99building yard of ,harvey and ,co41 of ,hayle1 an engine working a stamps for pounding up the slag and furnace bottoms from the brass-casting foundry4 ,i was then the foreman hammerman in ,harvey and ,co4's smiths' shop and hammer-mill1 and frequently noticed this old engine and inquired about it4 ,it had been brought from ,lord ,dedunstanville's1 at ,tehidy ,park1 where it at one time worked a thrashing machine4 ,the boiler was of wrought iron1 built in brickwork1 and looked like a big kitchen-boiler4 ,a flattish cover was bolted on to the top of the boiler1 and the cylinder was let down into this top4 ,the cylinder had no cover2 it was about #h or #aj inches in diameter and #b or #c feet stroke4 ,the piston was a very deep one1 with a joint for the connecting rod which went direct to the crank1 which was supported on two upright stands from the cover on the boiler4 ,the fly-wheel had a balance-weight for the down-stroke4 ,a pitch-chain for driving passed over the wheel1 which had pins in it1 or projections1 to catch into the square links of the driving chain2 it was worked by a four-way cock4#ag ,footnote #ag3 ,recollections of ,banfield1 foreman with ,harvey and ,co41 ,penzance1 #ahfi4 ,about #ahdc1 when we were building iron boats for the ,rhine1 the old engine was put to work to drive the tools or machinery in the yard4 ,she was very useful to us and worked very well4 ,she worked about ten years1 and was then thrown out to make room for a new and larger engine for our saw-mills4 ,the chain-wheel for driving was made here1 it did not belong to it originally4#ah ,footnote #ah3 ,recollections of ,mr4 ,warren1 master ship-builder1 ,harvey and ,co41 #ahfi4 ,my father 7then the foreman boiler-maker7 about twenty-four years ago took the old engine from the scrap heap1 where it had been for many years1 and set it to work in the tool shop4 ,my father said it had come from ,tehidy as old iron4#ai ,footnote #ai3 ,recollections of ,mr4 ,burral1 jun41 master boiler-maker1 ,harvey and ,co41 #ahfi4 ,the use of the high-pressure steam agricultural engine was not confined to ,cornwall4 ,mr4 ,h4 ,pape1 still carrying on business in ,hazeldine and ,rastrick's old engine manufactory at ,bridgenorth1 says3-- ,my father worked as a smith under ,mr4 ,rastrick4 ,mr4 ,hazeldine had the foundry when ,trevithick's engines were made1 and have heard my father speak of them4 ,i have seen three of them at work in ,bridgenorth2 one of them at ,mr4 ,jasper's flour-mill1 it drove four stones1 and continued in work up to #ahcg2 one at ,sing's tan-yard worked up to #ahdj2 and one was on ,mr4 ,jasper's farm at ,stapleford for doing farm work4 ,mr4 ,smith1 now on the farm1 worked it up to about #aheh4 ,the engines that worked in ,bridgenorth had cast-iron cylinders for the outer casing of the boiler1 one cylinder for small engines1 three or four cylinders bolted together for the larger ones4 ,the fire-tube was wrought iron1 the chimney stood up by the fire-door4 ,the cylinder was let down into the boiler2 it worked with a four-way cock4 ,there was a piston-rod1 cross-99head1 two guide-rods on the top of the cylinder1 and two side rods to the crank and pin in 'the fly-wheel4'#bj ,footnote #bj3 ,recollections of ,mr4 ,william ,h4 ,pape1 ,bridgenorth1 #acth ,june1 #ahfi4 ,my first husband had to do with the foundry2 his father1 ,mr4 ,hazeldine1 was a partner with ,mr4 ,davies and ,co4 in #ahaf4 ,in #ahag the partnership was broken up1 and the foundry carried on by ,hazeldine4 ,i used to have two or three drawers full of drawings and account-books that were brought from the works4 ,i kept them for many years1 but now the greater part of them have gone to light the fire2 all the drawings are gone4#ba ,footnote #ba3 ,recollections of ,mrs4 ,marm1 ,bridgenorth1 #abth ,june1 #ahfi4 ,the engines described by ,mr4 ,pape are of the type made by ,trevithick1 in ,wales1 about #ahjd1 having a fire-place in the boiler1 and similar in form to the ,welsh locomotive4 ,the drawings which served to light the fires certainly included ,trevithick's plans for the steam-locomotive1 ploughing engine1 the screw-propeller1 and many others of equal interest4 ,,dear ,,sir1 ,,stableford1 ,march #bfth1 #ahgj4 ,my grandfather's name was ,john ,jasper1 ,esq41 of ,stableford2 he must have been one1 if not the first1 user of a steam-engine for thrashing1 winnowing1 and shaking the straw all at one operation2 it may have been erected eighty years ago1 for an old servant of the family just now dead1 aged ninety1 worked when a boy in the steam-mill at ,bridgenorth erected by my grandfather about the same time4 ,the thrashing engine was a side-lever engine1 worked with a three side-way cock and tappet1 a cylinder about #h-a_/d inches in diameter1 and a #c feet #d inch stroke1 cast-iron crank-shaft1 cross-head1 and guides4 ,the boiler was placed underneath the engine1 the fire under it1 with brick flues4 ,the boiler was about #i feet long and #d feet diameter4 ,the old side rods made of wood are still here1 and so was the engine until about twelve years ago4 ,i sent the cylinder1 c41 to ,coalbrookdale4 ,i am1 ,sir1 ,yours truly1 ,,thomas ,,smith4 ,the ,stableford agricultural engine was probably made in #ahjd4 ,the cylinder1 of #h-a_/d inches in diameter1 is precisely the size of that in the ,welsh locomotive1 but the stroke was reduced from #d feet #f inches to #c feet #d inches1 being very nearly the same as the ,newcastle locomotive4 ,the cross-head1 side rods1 and boiler were very similar to the ,welsh stationary engines of that date4 ,this engine remained in use more than fifty years4 ,the engines specially referred to in this chapter fully prove1 from their length of service1 the practical character of ,trevithick's inventions1 and of his having persevered with his high-pressure portables until their usefulness as locomotives and as agricultural helps had been established2 but the ploughing1 though fully designed1 and probably put into practice1 was not followed up to the same approach to perfection1 or the record of its progress has been lost4 ,since the foregoing was written1 the following has been received3-- ,,dear ,,sir1 ,,trewithen1 ,,probus1 ,may #agth1 #ahgb4 ,the engine you refer to is still occasionally used here2 when first erected there was a large quantity of corn thrashed by it1 but of late years it has not been much used except for chaffing1 bruising1 c4 ,i remain1 dear ,sir1 ,yours truly1 ,,wm4 ,,trethnoy4 ,f4 ,,trevithick1 ,esq4 ,trevithick's ,trewithen engine1 which sixty years ago was more manageable than horses going momentarily faster or slower at the will of a common labourer1#bb remains in use unchanged4 ,footnote #bb3 ,see vol4 ii41 p4 #ch4 ,his preparations for ,south ,america1 and application of high steam in the large ,cornish pumping engines1 interfered with the perfecting the smaller agricultural work4 ,,chapter ,,xix4 ,,pole ,,steam-,,engine4 ,when in the autumn of #ahaj ,trevithick returned to ,cornwall1 the experience of ten busy years had established the practicability and usefulness of the high-pressure engine4 ,the principles of the invention were now to be applied on engines of the largest size4 ,in #ahaa1 the late ,captain ,s4 ,grose1 a young pupil of ,trevithick's1 was employed to erect at ,wheal ,prosper ,mine1 in ,gwythian1 the first high-pressure steam pole condensing engine4 ,it was placed immediately over the shaft and pump-rods1 requiring no engine-beam4 ,the air-pump1 feed-pump1 and plug-rod were worked from the balance-bob4 ,the pole was #af inches in diameter1 with a stroke of #h feet4 ,the boilers were two wrought-iron tubes1 #c feet in diameter and #dj feet long4 ,the fire was external4 ,shortly after ,captain ,h4 ,a4 ,artha erected several of those pole-engines for ,trevithick4 ,the drawing shows the simplicity of parts of this highly expansive steam-engine1 beginning the up-stroke with steam of #ajj lbs4 to the inch above the atmospheric pressure1 expanding it during the stroke down to a pressure of #aj lbs41 and then condensing to form a vacuum for the down-stroke4 ,it cost #gej guineas4 ,the drawings of this expansive pole condensing engine are from the dimensions given by ,captain ,grose who erected it1 and by ,captain ,artha who knew it well4 ,illustration3 ,,wheal ,,prosper ,,high-,,pressure ,,expansive ,,steam-,,condensing ,,pole-,,engine1 #ahaa4 a1 cast-iron pole1 #af inches diameter1 #h-;feet stroke2 b1 pole-case1 a small bit larger in internal diameter than the pole2 c1 cross-head1 fixed on top of pole2 d1 guides for cross-head2 e1 side rods connecting the two cross-heads9999typo beads corrected2 f1 bottom cross-head2 g1 pump-rod2 h1 balance-beam1 with box for weights2 i1 connecting rods from balance-beam to bottom cross-head2 k1 guides for air-pump cross-head2 l1 cross-head and side rods for working air-pump2 m1 air-pump1 condenser1 and water-cistern2 n1 feed-pump worked from air-pump cross-head2 o1 plug-rod worked from balance-beam2 p1 exhaust-valve2 q1 steam-valve2 r1 exhaust-pipe2 s1 steam-pipe2 t1 bracket for carrying working gear2 u1 expansive steam-horn and tappets2 v1 handles for working valves4 ,illustration3 ,,trevithick',s ,,cylindrical ,,boiler ,,for ,,wheal ,,prosper ,,engine1 #ahaa4 ,detail of ,boilers3--a1 two wrought-iron boilers1 #c feet in diameter1 #dj feet long1 using steam of #ajj lbs4 on the square inch above the atmosphere2 b1 cast-iron manhole door and safety-valve2 c1 ash-pit2 d1 fire-place2 e1 flues1 the fire going first the whole length under the bottom of the boiler1 then back again over the top1 and into the chimney2 f1 brickwork2 g1 ashes or other convenient non-99conductor of heat2 the fire-place ends of the boilers were #ae inches lower than the opposite ends1 increasing the safety1 with less liability to prime1 and greater surface for superheating4 ,when a boy ,i was placed as an apprentice or learner with ,captain ,trevithick1 before he left ,cornwall for ,london4 ,on his return to ,cornwall1 about #ahaj1 he employed me to erect his first high-pressure expansive pole pumping engine at a mine in ,gwythian4 ,the pole was #af inches in diameter2 the stroke was very long1 but ,i do not exactly recollect the length4 ,it had a condenser and air-pump4 ,there were two boilers made of wrought iron1 #h feet in diameter and #dj feet long4 ,the fire was placed under them at one end1 and flues went round them4 ,a feed-pump forced water into the boilers2 each had a safety-valve with a lever and weight4 ,the steam in the boiler was #ajj lbs4 to the square inch4 ,the pole was raised by the admission of the strong steam under its bottom4 ,the steam-valve was closed at an early part of the stroke1 and the steam allowed to expand2 at the end of the stroke it was reduced to #bj lbs4 or less1 when the exhaust-valve allowed the steam to pass to the condenser1 and the pole made its down-stroke in vacuum4 ,a balance-bob regulated the movement of the engine4 ,trevithick's character in those days was1 that he always began some new thing before he had finished the old4#bc ,footnote #bc3 ,captain ,samuel ,grose's recollections4 #aheh4 ,gwinear4 ,captain ,artha1 one of his assistants1 said3-- ,i erected several of ,captain ,trevithick's pole-engines4 ,my brother ,richard worked the one at ,wheal ,prosper when first erected4 ,the pole made an #h-;feet stroke4 ,the case was fixed over the engine-shaft on two beams of timber from wall to wall4 ,a cross-head was bolted to the top of the pole1 and from it two side rods descended to a cross-piece under the pole-case1 from which the pump-rod went into the shaft4 ,a connecting rod worked a balance-beam1 which worked the air-pump1 feed-pump1 and plug-rod for moving the valves4 ,the steam1 of a very high pressure1 worked expansively4#bd ,footnote #bd3 ,captain ,h4 ,a4 ,artha's recollections4 ,penzance1 #ahfi4 ,the first admission of the high-pressure steam under the pole was equal to a force of #h or #i tons1 causing it and its attached pump-rods to take a rapid upward spring4 ,having travelled #a or #b feet of its stroke of #h feet1 the further supply of steam from the boiler was cut off1 and its expansion1 together with the momentum of the mass of pump-rods1 completed the upward stroke4 ,the pressure of the steam in the pole-case at the finish of the up-stroke would be reduced to say #aj or #bj lbs4 to the inch1 according to the amount of work on the engine4 ,the steam then passed to the condenser and air-pump1 and the engine made its down-stroke by the vacuum under the pole1 and by the weight of the descending pole and pump-rods4 ,each boiler was a wrought-iron tube #c feet in diameter and #dj feet long1 the fire-place under one end1 with brick flues carrying the heated air under the whole length of the bottom of the boiler1 and back again over the top or steam portion for superheating4 ,rough draft4 ,,camborne1 #bhth ,february1 #ahac4 ,i will engage to erect a puffer steam-engine1 everything complete at the surface1 on the ,cost-all-lost ,mine1 capable of lifting an #h-;inch bucket1 #d-a_/b-;feet stroke1 twenty-four strokes per minute1 #cj fathoms deep1 or #bhj gallons of water per minute from that same depth1 being a duty equal thereto1 for #eej guineas4 ,but if a condensing engine1 #fjj guineas4 ,if of the same size as ,wheal ,prosper1 #gej guineas4 ,,richard ,,trevithick4 ,the engines1 erected in #ahaa or #ahab1 combined the novelty of the steam pole-engine1 with the use of high-pressure steam of #ajj lbs4 on the square inch1 and the comparatively untried principle of steam expansion1 carried to what in the present day is thought an extreme and unmanageable limit4 ,the ,wheal ,prosper engine fixed near the sea-shore at ,gwythian is referred to in ,trevithick's note to ,mr4 ,rastrick1#be as that new engine you saw near the sea-side1 with me1 is now lifting forty millions1 #a foot high1 with #a bushel of coal 7#hd lbs471 which is very nearly double the duty that is done by any other engine in the county4 ,footnote #be3 ,see ,trevithick's letter1 ,january #bfth1 #ahac1 chap1 xviii4 ,this was probably the first application of high-pressure steam to give motion to pump-rods4 ,the engine1 as compared with the neighbouring ,watt low-pressure steam vacuum pumping engines1 was small1 but the principles of high steam1 expansive working1 and vacuum1 were combined successfully to an extent scarcely ventured on by modern engineers4 ,trevithick's high-pressure condensing whim-engines had been for some years at work in ,cornwall1 but mine adventurers had not dared to risk the application of high-pressure steam to the large pumping engines1 fearing its great power would prove unmanageable1 and its rapid movement cause breakage of the pump-rods and valves4 ,two distinct inventions or improvements1 each of which was actually followed up in different mines1 show themselves in this engine3 one being the form of boiler to give with economy and safety high-pressure expansive steam for large engines2 the other1 the application of a pole in lieu of a piston1 as a more simple engine for working with strong expansive steam1 and more easily constructed by inexperienced mechanics1 who had none of the slide lathes or planing machines so much used by engine builders of the present day4 ,about #ahad ,captain ,trevithick erected a large high-pressure steam-puffer pumping engine at the ,herland ,mine4 ,the pole was about #cj inches in diameter1 and #aj or #ab feet stroke4 ,there was a cross-head on the top of the pole1 and side rods to a cross-head under the pole-case4 ,the side rods worked in guides4 ,the pole-case was fixed to strong beams immediately over the pump-shaft4 ,the steam was turned on and off by a four-way cock4 ,the pressure was #aej lbs4 to the inch above the atmosphere4 ,the boilers were of wrought iron1 cylindrical1 about #e feet #f inches in diameter and #dj feet long1 with an internal tube #c ft4 in diameter4 ,the fire-place was in the tube4 ,the return draught passed through external brick flues4#bf ,footnote #bf3 ,recollections of the late ,captain ,charles ,thomas1 manager of ,dolcoath ,mine4 ,when a young man1 living on a farm at ,gurlyn1 ,i was sent to ,gwinear to bring home six or seven bullocks4 ,herland ,mine was not much out of my way1 so ,i drove the bullocks across ,herland ,common toward the engine-house4 ,just as the bullocks came near the engine-house the engine was put to work4 ,the steam roared like thunder through an underground pipe about #ej feet long1 and then went off like a gun every stroke of the engine4 ,the bullocks galloped off--some one way and some another4 ,i went into the engine-house4 ,the engine was a great pole about #c feet in diameter and #ab feet long4 ,a cast-iron cross-head was bolted to the top of the pole4 ,it had side rods and guides4 ,a piece of iron sticking out from the cross-head carried the plug-rod for working the gear-handles4 ,the top of the pole worked in a stuffing box4 ,a large balance-beam was attached to the pump-rods1 near the bottom cross-head4 ,there were two or three of ,captain ,trevithick's boilers with a tube through them1 the fire in the tube4 ,they seemed to be placed in a pit in the ground4 ,the brick flues and top of the bricks were covered with ashes just level with the ground4 ,a great cloud of steam came from the covering of ashes4 ,i should think the pressure was more than #ajj lbs4 to the inch4 ,people used to say that she forked the mine better than two of ,boulton and ,watt's #hj-;inch cylinder engines4 ,we could hear the puffer blowing at ,gurlyn1 five or six miles from the ,herland ,mine4 ,in #ahac ,i carried rivets to make ,captain ,trevithick's boilers in the ,mellinear ,mine2 they were #e feet in diameter and #cj or #dj feet long1 with an internal fire-tube4 ,it took four or five months to build them4 ,in the present day 7#ahfi7 a fortnight would build them4 ,the largest boiler-plates obtainable were #c feet by #a foot4 ,we had to hammer them into the proper curve4 ,the rivet-holes were not opposite one another4 ,a light hammer was held against the rivet-head in riveting1 in place of the present heavy one1 so the rivet used to slip about1 and the plates were never hammered home so as to make a tight joint4#bg ,footnote #bg3 ,recollections of ,mr4 ,james ,banfield1 ,penzance1 #ahga4 ,lest the reader should doubt the comparative power of the ,watt low-pressure vacuum and ,trevithick's high-pressure steam-engines1 a short but sufficiently close calculation shows that taking ,stuart's#bh estimate of the effective power of the ,watt engine at #h-a_/b lbs4 on each square inch of the piston1 and ,trevithick's engine at anything approaching to #aej lbs4 on each square inch1 it becomes evident that the latter would be ten or twenty times more powerful than the former4 ,a few figures will put the question in more practical form4 ,footnote #bh3 ,see ,stuart's ',history of the ,steam-,engine4' ,the ,wheal ,prosper #af-;inch pole high-pressure expansive steam vacuum engine commenced its up-stroke with steam of #ajj lbs4 on the inch1 acting on the #abb square inches of the pole1 which steam at the finish of the stroke was reduced by expansion to #aj lbs41 giving1 say1 an average steam pressure of #ee lbs4 ,the down-stroke was caused by a vacuum under the pole of #ad lbs4 on the inch1 reduced by1 say1 one-third loss in working the air-pump to #i lbs41 giving from the compound stroke a force of #fd lbs4 on each square inch1 which1 multiplied by the area of the pole1 gives a net force of #ghjh lbs4 ,the ,herland #cc-;inch pole high-pressure expansive steam puffer-engine commenced its up-stroke with steam of #aej lbs4 on the inch1 acting on the #hee square inches of the pole1 which steam at the finish of the stroke--we will suppose--was reduced by expansion to #ge lbs41 giving an average steam pressure of1 say1 #aab4 ,as this puffer-engine used no vacuum1 the down-stroke gave no increase of power2 its compound stroke was therefore a force of #aab lbs4 on each square inch1 which1 multiplied by the area of the pole1 gives a net force of #ie1gfj lbs4 ,to compare the ,trevithick high-pressure steam pumping engine1 with the ,watt low-pressure steam pumping engine1 take one of the largest of the latter1 made about that time1 say1 with an #hj-;inch cylinder1 which commenced its down-stroke with steam of1 say1 #c lbs4 on the inch1 acting on the #ejjj square inches of the piston1 which steam at the finish of the stroke--the writer is describing the usage at that time1 for ,watt himself advocated a less steam pressure--was reduced by expansion to1 say1 #a lb41 giving an average steam pressure of1 say1 #b lbs4 on the top of the piston1 whose under side was in vacuum equal to #ad lbs4 on the inch1 reduced by1 say1 one-third loss in working the air-pump to #i lbs41 which power1 from vacuum added to the #b lbs4 from steam1 gives a net force of #aa lbs4 on each square inch of the piston4 ,as the ,watt pumping engine moved in equilibrium during its up-stroke1 it thereby gained no increase of power2 its compound stroke was therefore a force of #aa lbs4 on each square inch1 which1 multiplied by the area of the piston1 gives a net force of #ee1jjj lbs4 ,the practical comparison therefore stands1--,trevithick's #af-;inch pole high-pressure steam1 and vacuum1 on each inch #fd lbs41 net force #ghjh lbs42 ,trevithick's #cc-;inch pole high-pressure steam1 without vacuum1 on each inch #aab lbs41 net force #ie1gfj lbs42 ,watt's #hj-;inch piston1 low-pressure steam1 and vacuum1 on each inch #aa lbs41 net force #ee1jjj lbs4 ,as the first cost was mainly dependent on the size1 the ,trevithick engine was commercially much more valuable than the ,watt engine4 ,i saw ,captain ,trevithick's puffer working at the ,herland ,mine4 ,the steam used to blow off like blue fire--it was so strong4 ,the lever on the safety-valve was about #c feet long1 with a great weight on it1 more than a hundredweight4 ,the engine did not answer very well1 for the packing in the pole stuffing box used to burn out1 and a cloud of steam escaped4 ,the greatest difficulty was in the leaking of the boilers4 ,you could hardly go near them4 ,before that time we always put rope-yarn between the lap of the boiler-plates to make the seams tight4 ,captain ,dick's high-pressure steam burnt it all out4 ,he said1 ',now you shall never make another boiler for me with rope-yarn4' ,everybody said it was impossible to make a tight boiler without it4 ,we put barrowfuls of horse-dung and bran in ,captain ,dick's boilers to stop the leaks4#bi ,footnote #bi3 ,henry ,clark of ,redruth1 in #ahfi1 aged eighty-three years4 ,this difficulty of making a tight and safe boiler1 that puzzled ,watt1 was moonshine to ,trevithick4 ,when the strained boiler and flinching rivets allowed the boiler-house to become full of dense steam1 ,trevithick told them to cover it up with ashes1 they would not see it quite so much then1 and it would keep the heat in the boiler4 ,bran or horse-dung inside was a good thing as a stop-gap1 though it added not to the strength of the boiler4 ,trevithick was himself in a cloud of steam in the engine-house2 yet1 with such surroundings1 he turned on and off his gunpowder steam1 from his cannon of a pole-case1 of #dj tons force1 sending his bolt-shot pole1 #cc inches in diameter1 its destined course of ten feet1 and back again1 as though it were a shuttlecock1 several times in a minute4 ,having by one or two years of experience proved the value of his new pole-engine1 he applied for a patent on the #acth ,june1 #ahae1cj of which the following is the portion referring particularly to the pole-engine3-- ,footnote #cj3 ,see full copy of patent1 chap4 xvi4 ,instead of a piston working in the main cylinder of the steam-engine1 ,i do use a plunger-pole similar to those employed in pumps for lifting water1 and ,i do make the said plunger-pole nearly of the same diameter as the working cylinder1 having only space enough between the pole and the cylinder to prevent friction1 or1 in case the steam is admitted near the stuffing box1 ,i leave sufficient room for the steam to pass to the bottom of the cylinder1 and ,i do make at the upper end of the cylinder for the plunger-pole to pass through a stuffing box of much greater depth than usual1 into which stuffing box ,i do introduce enough of the usual packing to fill it one-third high4 ,upon this packing ,i place a ring of metal1 occupying about another third part of the depth of the stuffing box1 this ring having a circular groove at the inside1 and a hole or holes through it communicating with the outside1 and with a hole through the side of the stuffing box2 or1 instead of one ring containing a groove1 ,i sometimes place two thinner rings1 kept asunder by a number of pillars to about the distance of one-third of the depth of the stuffing box1 and ,i pack the remaining space above the ring or rings1 and secure the whole down in the usual manner4 ,the intention of this arrangement is to produce the effect of two stuffing boxes1 allowing a space between the two stuffings for water to pass freely in from the boiler or forcing pump through a pipe and through the hole in the side of the stuffing box1 so as to surround the plunger-pole and form the ring of water for the purpose of preventing the escape of steam by keeping up an equilibrium between the water above the lower stuffing and the steam in the cylinder4 ,by this part of my said invention ,i obviate the necessity of that tight packing which is requisite when steam of a high pressure is used1 and consequently ,i avoid a greater proportion of the usual friction1 because a very moderate degree of tightness in the packing is quite sufficient to prevent the passage of any injurious quantity of so dense a fluid as water4 ,and ,i do further declare that ,i use the plunger-pole1 working in a cylinder and through a double stuffing1 either with or without a condenser1 according to the nature of the work which the steam-engine is to perform4 ,though ,trevithick has been spoken of as a visionary1 intractable schemer1 observation shows that he adhered with tenacity to original ideas1 proved to be good4 ,the plunger-pole pump1 the water-pressure engine1 the ,camborne locomotive1 the pole steam-engine1 were all built on the same groundwork originally started with1 of greatest simplicity of form1 and absence of many pieces2 and it may be observed that he never applied for a patent until the value of the idea had been proved by experiment4 ,in practice the difficulty of keeping the pole-packing in order was one of the objections to the plan2 for it either leaked1 or1 if packed tight1 caused much friction and wearing away of the middle of the pole faster than the ends1 from the greater speed at the middle of the stroke4 ,the steam-ring was therefore of importance in the engine1 in those days of inaccurate workmanship2 like the water cup on the gland of the plunger-pump packing1 it prevented external air from injuring the vacuum4 ,,mr4 ,,giddy1 ,,camborne1 ,july #hth1 #ahae4 ,sir1--,about a fortnight since ,i received letters from ,lima1 and also letters to the friends of the men who sailed with the engines4 ,they arrived on the #bith ,january1 after a very good passage1 and without one hour's sickness4 ,both their and my agreements were immediately ratified1 and they are in high spirits4 ,the ship finished discharging on the #aath ,february1 which was the day those letters sailed from ,lima with #ab1jjj for me1 which has all arrived safe4 ,i shall make another fit-out for them immediately4 ,i expect that all the engines will be at work before the end of ,october2 half of them must be at work before this time4 ,the next day1 after their letters sailed for ,europe1 they intended to go back to the mines4 ,woolf's engine is stopped at ,herland1 and ,i have orders to proceed4 ,a great part of the work is finished for them1 and will be at work within two months from the time ,i began4 ,i only engage that the engine shall be equal to a ,b4 and ,watt's #gb-;inch single1 but it will be equal to a double #gb-;inch cylinder4 ,it is a cast-iron plunger-pole1 over the shaft1 of #cc inches diameter1 #aj-;feet stroke4 ,the boiler is two tubes1 #de feet long each1 #c feet diameter1 #a_/b an inch thick1 of wrought iron1 side by side1 nearly horizontal1 only #ae inches higher at the steam end of the tubes1 to allow the free passage of steam to the steam-pipe4 ,there are two #d-;inch valves1 one the steam-valve1 the other the discharging valve4 ,i have made the plunger-case and steam-vessel of wrought iron #c_/d of an inch thick4 ,the steam-vessel is #dh inches in diameter4 ,the plunger stands on beams over the shaft1 with the top of it at the level of the surface1 with a short ,t-piece above the plunger-pole1 and a side rod on each side1 that comes up between the two plunger-beams in the shaft2 this does away with the use of an engine-beam1 and the plungers do away with the use of a balance-beam4 ,illustration3 ,,pole-,,engine4 ,the fire is under the two tubes1 and goes under them for #de feet1 and then returns again over them1 and then up the chimney4 ,those tubes need no boiler-house1 because they are arched over with brick1 which keeps them from the weather1 and scarcely any engine-house is needed1 only just to cover the engineman4 ,suppose a #gb-;inch cylinder 7having #djjj inches71 at #aj lbs4 to the inch1 an #h-;feet stroke1 working nine strokes per minute 7which is more strokes of that length than she will make when loaded to #aj lbs4 to the inch74 ,inches4 #djjj in a #gb-;inch cylinder1 single4 #aj lbs4 to the inch4 ------- #djjjj #h feet stroke4 ------- #cbjjjj #i strokes per minute4 ------- #bhhjjjj lbs4 lifted one foot high per minute4 ------- ,suppose a #cc-;inch plunger-pole1 #aj-;feet stroke1 ten strokes per minute 7which is not so fast by three or four strokes per minute as this engine will go1 because she will have no heavy beam to return1 neither will she have to wait for condensing1 like ,b4 and ,watt's1 which1 when loaded1 hangs very long on the injection74 #hee square inches in a #cc-;inch plunger-pole4 #aj strokes per minute4 ------- #heej #aj feet stroke4 ------- #heejj #cd lbs4 to the inch1 real duty4 ------- #cdbjjj #befejj ------- #bijgjjj lbs4 lifted one foot high per minute4 ------- ,i should judge that less than #ej lbs4 to the inch above the atmosphere would be quite enough to do the work of a #gb-;inch cylinder single1 which is but a trifle for those wrought-iron tubes to stand4 ,this engine1 everything new1 house included1 ready for work1 will not exceed #gjjl4 ,two months are sufficient for erecting it4 ,the engine of ,woolf's1 at ,wheal ,vor1 which is but two-thirds the power of a #gb-;inch cylinder1 single power1 cost #hjjjl41 and was two years erecting4 ,i would be much obliged to you for your opinion on this business4 ,i remain1 ,sir1 ,your very humble servant1 ,richard ,trevithick4 ,i am sorry to say that the mines in general are very poor4 ,he shows that with steam of #cd lbs4 to the inch1 his ,herland pole puffer steam-engine of #cc inches in diameter would be equal in power to the ,watt low-pressure steam vacuum engine1 with a #gb-;inch cylinder4 ,herland1 like ,dolcoath and ,wheal ,treasury1 was the chosen battle-ground of rival engineers2 fifty years after ,newcomen had there erected his famously large #gj-;inch cylinder engine1 ,watt surpassed it in size by a cylinder #b inches more in diameter1 and1 after personally superintending its erection in #agih1 declared that it could not be improved on4 ,mr4 ,davey1 the mine manager1 considered that it did twenty millions of duty1 though ,mr4 ,watt had made it twenty-seven millions with a bushel of coal4#ca ,this difference is probably explained by the then ,cornish bushel weighing #hd lbs41 while ,watt generally calculated a bushel at #aab lbs4 ,footnote #ca3 ,lean's ',historical ,statement of the ,steam-,engine1' p4 #g4 ,trevithick declining to believe ,watt's prognostication1 a public test of ,watt's engines in the county was demanded2 ,mr4 ,davies ,gilbert1 with ,mr4 ,jenkin1 were requested to report on their duty1 and gave it in #agih as averaging seventeen millions4#cb ,during the same year the adventurers in ,herland ,mine engaged ,trevithick and ,bull1 jun41 to erect a #fj-;inch cylinder ,bull engine to compete with ,watt's #gb-;inch cylinder4 ,the result of this fight is not traceable1 nor what took place there during the succeeding fifteen years2 when in #ahad ,woolf erected in ,cornwall his double-cylinder engine to compete with ,watt's engine1 and ,trevithick attacked them both with his ,herland high-pressure pole puffer in #ahae1 when he erected at his own risk and cost a #cc-;inch pole-engine1 engaging that it should1 both in power and economical duty1 equal the ,watt #gb-;inch engine4 ,the boilers were similar in form to those used a year before in ,wheal ,prosper high-pressure steam vacuum pole-engine1 being two wrought-iron tubes1 each #de feet long and #c feet in diameter1 made of plates half an inch thick4 ,the fire was in external flues4 ,the engine was fixed directly over the pump-rods in the shaft1 using neither main beam nor air-pump4 ,footnote #cb3 ,lean's ',historical ,statement of the ,steam-,engine1' p4 #g4 ,trevithick's rough hand-sketch shows the steam-ring in the stuffing box and the steam-vessel2 the particular use of the latter he has not described3 probably it was because ,cornish pumping engines1 not having the controlling crank to limit the movement of the piston1 are obliged to trust to the very admirable1 but little understood1 steam-cushion1 without which the ascending piston would inevitably strike and break the cylinder-cover1 while in the pole puffer-engine this danger was during the descent of the pole1 and therefore the discharge-steam valve was closed1 while the steam in the pole-case was still of ten or more pounds to the inch1 so that by the time the pole reached the finish of its down-stroke1 it had compressed this steam-cushion1 filling also the steam-vessel1 with a pressure approaching to that in the boiler1 and equal to the weight of the pole and pump-rods4 ,a comparatively small supply of steam from the boiler into the steam-vessel brought it up to the boiler pressure1 sending the pole and pump-rods upwards with a spring4 ,the steam-valve then closed1 allowing the momentum of the great weight of pump-rods1 together with the expanding steam1 to complete the up-stroke4 ,the discharge-valve was then opened for a moment1 allowing a blast of steam to escape1 reducing the pressure say to one-half4 ,the weight of the rods caused their downward movement1 raising the load of water in the plunger-pole pumps1 and at the same time compressing the steam from the pole-case into the steam-vessel1 equal at the finish of the stroke to the support of the pole and pump-rods4 ,this most simple steam-engine combined in the greatest degree the two elements of expansion and momentum4 ,the up-stroke began with a much higher pressure of steam than was necessary to raise the load2 having given momentum to the rods1 the supply of steam was cut off1 and the stroke was completed by expansion4 ,the down-stroke began with a comparatively low pressure of steam under the pole4 ,the unsupported pump-rods fell downwards1 setting in upward motion the column of water in the plunger-pole pumps4 ,the discharge-valve was closed long before the completion of the down-stroke1 and the momentum of the moving mass of rods and water compressed the steam driven from the pole-case into the steam-vessel up to a pressure equal to the support of the pole and pump-rods4 ,the pole was1 therefore1 continually floating or rising and falling in steam of ever-varying pressure4 ,trevithick' s figures show the working power of the #cc-;inch pole as much greater than ,watt's #gb-;inch cylinder engine1 even when the steam pressure in the former was much reduced1 and that ,woolf's double-cylinder engine1 of less power1 cost ten times as much as the pole-engine4 ,this sum probably included the costly buildings required for the beam-engines1 which ,trevithick's plan dispensed with4 ,the reader may judge of the perfection of mechanism in this plain-looking engine from the fact that a pole1 with #aej lbs4 of steam to the inch in the boiler1 was equal to #ej or #fj tons weight1 thrown up and down its #aj-;feet stroke ten or fourteen times a minute1 with a limit of movement perfectly under control1 while modern engineers are building ships' turrets because of the difficulty of raising and depressing a #cj-ton gun from the hold to above the water level4 ,rough draft4 ,,sir1 ,,camborne1 ,september #abth1 #ahae4 ,i received a letter dated the #bjth of ,august1 from ,mr4 ,davies1 in which he did not mention the name of ,herland castings4 ,on the #bdth of the same month ,i wrote to you1 informing you of the same1 and requesting to know what state of forwardness the castings were in4 ,on the #cjth of ,august ,i received another letter from ,mr4 ,davies1 not saying what state of forwardness the castings were in1 nor when they would be finished1 only that they would set their hands about them1 and that ,i might expect a letter from you stating the particulars1 which has not yet come to hand4 ,i have waited so long that ,i am quite out of patience4 ,you will know that it is now nearly double the time that the castings were to have been finished in1 and you have not yet answered my letters as to the state of the castings nor when they will be finished4 ,i must again request you to write to me on this subject1 otherwise ,i must immediately remove the orders to some other founders that may be a little more attentive to their customers4 ,i must be informed in the positive1 whether the castings will be at ,bristol by the next spring-tide1 as a vessel is engaged for the purpose of taking them to ,cornwall4 ,yours1 c41 ,r4 ,t4 ,,mr4 ,,john ,,rastrick1 ,chepstow1 ,south ,wales4 ,rastrick1 whom he had known at the ,thames ,driftway1 had become the managing engineer at the ,bridgenorth ,foundry4 ,rough draft4 ,,mr4 ,,george ,,cowie1 ,,camborne1 ,september #bith1 #ahae4 ,i received your favour of the #bjth1 and on the #bcrd called on ,mr4 ,wm4 ,sims1 your engineer1 who went with me to ,beeralstone ,mine the same day4 ,we arranged on the spot what was necessary for the engine4 ,i hope it will be at work in good time1 before the winter's floods set in4 ,nothing can prevent it1 unless the castings are detained by contrary winds4 ,the boilers are nearly finished in ,cornwall4 ,the castings at ,bridgenorth are in a forward state4 ,i intend leaving this evening for ,bridgenorth1 to ship the castings1 both for ,herland and ,beeralstone4 ,it was the wish of the agents on the mine that these castings might be sent to ,swansea1 and taken from thence to the mine with a freight of coal4 ,i shall1 if possible1 get the ,herland castings in the same ship4 ,the workmen making your boilers want an advance of cash to enable them to finish4 ,they provide both iron and labour1 for which they are to receive #dbl4 per ton for the boiler when finished2 the weight will be about #h tons4 ,you may send this money to ,mr4 ,sims or to me1 or otherwise you may direct it to ,mr4 ,n4 ,holman1 boiler-maker1 ,pool1 near ,truro4 #ajjl4 will satisfy them for the present4 ,i hope to be in ,london this day week1 and will call at your office4 ,yours1 c41 ,r4 ,,trevithick4 ,the pole-engine was not only used in several mines shortly after its first introduction1 but ,mr4 ,sims1 the leading engineer of the eastern mines1 not generally favourable to ,trevithick1 advocated its application in the traditional ,watt district4 ,scarcely had he smoothed the way with one opponent than another sprung up in an unexpected quarter4 ,his brother-in-law1 ,harvey1 with his once friend1 ,andrew ,vivian1 then a partner with ,harvey1 opposed his plans at the ,herland4 ,they were annoyed at ,trevithick's sending his orders for castings and machinery to ,bridgenorth1 and may have had doubts of the success of the new inventions4 ,they had authority in the mine1 probably as shareholders1 a position generally acquired in ,cornwall by those who supply necessary mine material1 as well as by the smelters who buy the mineral from the mines4 ,the ,williamses and ,foxes1 controlling the eastern district of mines1 were also shareholders and managers1 supplying machinery and buying the mine produce4 ,rough draft4 ,,sir1 ,,penzance1 #acth ,december1 #ahae4 ,yesterday ,i was at ,herland1 where ,i was informed that ,captain ,andrew ,vivian had been the day before1 on his return from ,mr4 ,harvey's1 and discharged all the men on the mine1 without giving them a moment's notice4 ,before the arrival of the castings the pitmen1 sumpmen1 carpenters1 and smiths were very busy getting the pit-work ready2 at which time ,h4 ,harvey and ,a4 ,vivian were exulting in reporting that the iron ore was not yet raised that was to make the ,herland castings4 ,the day that they heard of their arrival they discharged all the labourers1 and ordered the agents not to admit another sixpence-worth of materials on the adventurers' account1 or employ any person whatever4 ,the agents sent a short time since to ,perran ,foundry#cc for the iron saddles and brasses belonging to the balance-bob1 the property of the adventurers2 but they refused to make them1 with a great deal of ill-natured language about my engine4 ,footnote #cc3 ,belonging to ,williams and ,co4 ,i am determined to fulfil my engagement with the adventurers1 and yesterday ordered all the smiths1 carpenters1 pitmen1 and sumpmen to prepare the adventurers' pit-work1 and ordered the agents to get the balance-bob and every other thing that may be wanted at my expense1 so as to fork the first lift1 which ,i hope to have dry by ,monday three weeks4 ,the engine will be in the mine this week1 and in one fortnight after ,i hope the engine will be at work1 and in less than a week more the first twenty fathoms under the adit will be dry4 ,in consequence of the ,perran people refusing to send the saddles and brasses for the balance-bob1 we will make shift in the best way we can without them4 ,the brasses ,i have ordered on my own account at ,mr4 ,scantlebury's4 ,the coals for the smiths ,i have also ordered1 and the same for the engine to fork the first lift4 ,this is very uncivil treatment in return for inventing and bringing to the public1 at my own risk and expense1 what ,i believe the country could not exist without4 ,i am determined to erect the engine at all events and upset this coalition before ,i leave ,europe1 if it detains me one year to accomplish it4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,,mr4 ,,phillip1 ,george ,yard1 ,lombard ,street4 ,p4,s4--,i should be glad to hear from you what is going forward respecting an arrangement of the shares4 ,rough draft4 ,,gentlemen1 ,,penzance1 #bcrd ,december1 #ahae4 ,i have received the ,herland castings1 and am very seriously sorry to say1 after we had fixed together the castings on the mine and made the joints1 on attempting to put the plunger-pole into the case it would not go down2 neither would either of the rings go to their places into the cylinder and on to the pole2 therefore the whole engine must be again taken to pieces and sent to a turning and boring mill to be newly turned and bored4 ,how to get this done ,i cannot tell1 for the founders here will not do it because they had not the casting them4 ,already great expenses have been incurred by delays1 and now to send them back to ,bridgenorth at an immense loss of time and money will be a very serious business indeed4 ,i think that either the cylinder is bored crooked or the plunger-pole turned crooked1 or both1 as it will sink farther down into the cylinder on turning it round on one side than it will on the other4 ,the whole job is most shamefully fitted up1 and was never tried together before sent off4 ,write to me by return of post and say what ,i am to do in this dilemma4 ,yours1 c41 ,,richard ,,trevithick4 ,,hazeldine1 ,,rastrick1 ,,and ,,co41 ,bridgenorth4 ,the new engine-work from ,bridgenorth on arrival was found to be so inaccurately made that the pole would not go into the pole-case4 ,henry ,phillips1#cd who saw the engine make its first start1 says3-- ,footnote #cd3 ,still working in ,harvey's foundry at ,hayle1 #ahfi4 ,i was a boy working in the mine1 and several of us peeped in at the door to see what was doing4 ,captain ,dick was in a great way1 the engine would not start2 after a bit ,captain ,dick threw himself down upon the floor of the engine-house1 and there he lay upon his back2 then up he jumped1 and snatched a sledge-hammer out of the hands of a man who was driving in a wedge1 and lashed it home in a minute4 ,there never was a man could use a sledge like ,captain ,dick2 he was as strong as a bull4 ,then1 he picked up a spanner and unscrewed something1 and off she went4 ,captain ,vivian was near me1 looking in at the doorway2 ,captain ,dick saw him1 and shaking his fist1 said3 ',if you come in here ,i'll throw you down the shaft4' ,i suppose ,captain ,vivian had something to do with making the boilers1 and ,captain ,dick was angry because they leaked clouds of steam4 ,you could hardly see1 or hear anybody speak in the engine-house1 it was so full of steam and noise2 we could hear the steam-puffer roaring at ,st4 ,erth1 more than three miles off4 ,by the end of ,january1 #ahaf1 the engine was ready for work1 and after ten days of experience1 he thus described the result3-- ,,mr4 ,,davies ,,giddy1 ,m4,p41 ,,penzance1 #aath ,february1 #ahaf4 ,sir1--,i was unwilling to write you until ,i had made a little trial of the ,herland engine4 ,it has been at work about ten days1 and works exceedingly well2 everyone who has seen it is satisfied that it is the best engine ever erected4 ,it goes more smoothly than any engine ,i ever saw1 and is very easy and regular in its stroke4 ,it's a #cc-;inch cylinder1 #aj-a_/b-;feet stroke4 ,we have driven it eighteen strokes per minute4 ,in the middle1 or about two-thirds of the stroke1 it moved about #h feet per second1 with a matter in motion of #bd tons2 and that weight returned thirty-six times in a minute1 with #b bushels of coal per hour4 ,this of itself1 without the friction1 or load of water1 is far more duty than ever was done before by an engine4 ,i found that it required about #hj lbs4 to the inch to work the engine the first twelve hours1 going one-third expansive1 twelve strokes per minute1 #aj-a_/b-;feet stroke1 with #bd bushels of coal4 ,the load of water was about #cj1jjj4 ,this was occasioned by the extreme friction1 the plunger-pole being turned1 and the plunger-case bored1 to fit so nicely from end to end1 that it was with great difficulty we could at all force the plunger-pole down to the bottom of the plunger-case4 ,this is now in a great degree removed1 and since we went to work we have thrown into the balance-box #d tons of balance1 and it would carry #c tons more at this time4 ,we must have carried that load in friction against the engine1 therefore1 if you calculate this1 you will find it did an immense duty1 going twelve strokes per minute1 #aj-a_/b-;feet stroke1 with #b bushels of coal per hour4 ,the engine is now working regularly twelve strokes per minute1 with #fj lbs4 of steam1 #aj-a_/b-;feet stroke1 three-quarters of the stroke expansive1 and ends with the steam rather under atmosphere strong1 with considerably within #b bushels of coal per hour4 ,i would drive her faster1 but as the lift is hanging in the capstan rope under water1 they are not willing to risk it4 ,i have raised the steam to #abj lbs4 to the inch1 the joints and everything perfectly tight4 ,i took the packing out of the stuffing box and examined it1 and found that the heat had not at all injured it2 the packing is perfectly tight1 not a particle of steam is lost4 ,i have offered to deposit #ajjjl4 to #ejjl4 as a bet against ,woolf's best engine1 and give him twenty millions1 but that party refuses to accept the challenge4 ,i have no doubt but that by the time she is in fork she will do #ajj millions1 which is the general opinion here4 ,the boilers are certainly the best ever invented1 as well as the other parts4 ,the draught is the best you ever saw2 ,i have only one-quarter part of the fire-bars uncovered1 yet from one-quarter part of the fire-place that ,i first made1 ,i find plenty of steam4 ,the greatest part of the waste steam is condensed in heating the water to fill the boiler2 what escapes is a mere nothing4 ,the engine will be loaded1 when in fork1 about #eb lbs4 to the inch4 ,now suppose ,i raise the steam so high at the first part of the stroke as to go so expansive as to leave the steam1 at the finish1 only atmosphere strong1 shall ,i1 in that case1 use any more coal than at present8 ,the materials and joints will stand far more than that pressure2 #ejj lbs4 to the inch would not injure them4 ,when the engine gets on two lifts1 ,i will write to you again1 and in the meantime please to give me your thoughts on the engine4 ,every engine that was erecting is stopped1 and the whole county thinks of no other engine4 ,your very obedient servant1 ,,rd4 ,,trevithick4 ,the new pole puffer-engine worked so satisfactorily and its movements were so manageable that the length of the stroke was increased by the spare #f inches1 which had been allowed as a margin in case of its overrunning its intended stroke4 ,it would bear being worked at eighteen strokes a minute1 while the ,watt #gb-;inch engine did not exceed nine strokes a minute2 with steam in the boiler of #hj lbs4 to the inch it performed its work when the steam supply was cut off at two-thirds of the stroke1 completing it by expansion4 ,it also worked well with steam of #abj lbs4 to the inch2 but the want of strength in the pump-rods and the requirements of the mine caused the regular working pressure of steam to be reduced to #fj lbs4 on the inch1 and to be cut off when the pole had moved through the first quarter of its stroke4 ,the excellent draught causing the fire-bars to be reduced to one-quarter of their original surface1 and the heating the feed-water by the waste steam in this powerful pumping engine1 indicate the use of the blast-pipe as at that time worked in the ,welsh puddling-mill engine4 ,watt's engine was for a moment forgotten1 that he might challenge ,woolf to a trial1 giving him as a help twenty millions1 or the understood duty of the ,watt engine4 ,this non-condensing pole-engine1 with #bj tons of pump-rods1 moved at a maximum speed of #h feet a second1 and was equal to its work with a steam pressure of #eb lbs4 on the inch4 ,trevithick contemplated extending the expansive principle even further than he had done in the ,wheal ,prosper pole condensing engine1 so that at the finish of the up-stroke the steam should only be about the pressure of the atmosphere1 or say from #a to #aj lbs4 on the inch1 having commenced it with steam of from #ajj to #bjj lbs4 on the inch1 and cutting off the supply from the boiler when the pole had gone but a very small part of its upward stroke1 more or less as the mine requirements admitted of it4 ,the principle of expansive working and momentum of moving parts was of necessity modified in its application to pump-work4 ,,dear ,,trevithick1 ,,eastbourne1 ,february #aeth1 #ahaf4 ,i have been called here by the decease of my wife's uncle1 and consequently your letters of the #aath did not reach me till this day4 ,the account you give me of your new engine has been extremely gratifying4 ,the duty performed by the engine in giving a velocity of #h feet in a second1 thirty-six different times in a minute1 to #bd tons of matter1 by the consumption of #b bushels of coal in an hour1 is indeed very great1 amounting to about fifty-seven and three-quarter millions4 ,so that when you obtain a proper burden1 and the extraordinary friction arising from the too close fitting of the plunger-pole and case is reduced1 there seems to be no doubt of your engine performing wonders4 ,i am of opinion that the stronger steam is used1 the more advantageous it will be found4 ,to what degree it should be applied expansively must be determined by experience in different cases4 ,it will depend on the rate at which the engine requires to be worked1 and on the quantity of matter put into motion1 so that as large a portion as possible of the inertia given in the beginning of the stroke may be taken out of it at the end4 ,some recent experiments made in ,france prove1 as ,i am told1 for ,i have not seen them1 that very little heat is consumed in raising the temperature of steam4 ,and if this is true1 of course there must be a great saving of fuel by using steam of several atmospheres' strength1 and working expansive through a large portion of the cylinder4 ,i have really been impatient for a week past to receive some account of your machine1 having learned nothing about it1 except from a paragraph dated ,hayle in the ,truro paper of last ,saturday week1 and somehow or other the next paper has not reached me1 ,i hope to be in ,london about ,tuesday next1 but at all events direct to me there1 as my letters are regularly forwarded4 ,believe me1 dear ,sir1 ,yours ever most faithfully1 ,,davies ,,giddy4 ,rough draft1 ,,mr4 ,,john ,,adams1 ,,bromsgrove1 #hth ,march1 #ahaf4 ,sir1--,i received your favour of the #abth ,february1 but did not answer it in due course1 because ,i was then erecting an engine on the new plan1 which is now at work1 and performs exceedingly well4 ,it is equal in power to a #gb-;inch diameter cylinder1 double power of ,b4 and ,watt's4 ,the expense of erection1 and the consumption of coals in this engine1 are not one-third of a ,b4 and ,watt's to perform the same work4 ,i am the same ,trevithick that invented the high-pressure engine4 ,i have sent out nine steam-engines to the gold and silver mines of ,peru4 ,i intend to sail for that place in about a month or six weeks1 but shall appoint agents in ,england to erect these engines4 ,no publication or description whatever has been in circulation1 neither is it required1 for ,i have a great many more orders than ,i can execute4 ,i have not seen anything of ,mr4 ,losh's patent engine1 or ,mr4 ,collins'4 ,if you should go to ,london ,i advise you to call on ,mr4 ,jas4 ,smith1 ,limekiln ,lane1 ,greenwich1 who is an agent for me1 and will soon be able to show you an engine on this plan at work4 ,i remain1 c41 ,r4 ,,trevithick4 ,unless the foregoing letters are based on error1 the only conclusion to be drawn is that ,watt1 on the expiry of his patent right and of twenty-eight years of labour1 having erected his masterpiece in ,cornwall1 was within a few years so beaten that ,trevithick1 in his challenge to ,woolf1 offered to throw in the ,watt engine as a make-99weight1 and with such odds to bet him two to one that his comparatively small and cheap high-pressure engine should beat the two big ones1 both in power1 in first cost1 and in economical working4 ,the ,watt engine was one of his largest1 with a #gb-;inch cylinder4 ,its power was equal to ,trevithick's #cc-;inch pole-engine1 when worked with steam of #cd lbs4 to the inch2 but the latter also worked with three times that pressure of steam1 whereby its power was increased threefold4 ,the first cost of these engines was probably in inverse proportion to their power4 ,trevithick's cost #gjjl41 while three times that sum would not pay for the ,watt engine4 ,the reported duty of ,watt's ,herland engine was twenty-seven millions2 and if the trial was with his ordinary bushel of #aab lbs4 of coal1 the duty would only be equal to twenty millions with #hd lbs4 of coal1 which constituted the ,cornish bushel4 ,trevithick's pole high-pressure steam-engine did fifty-seven millions2 in other words1 performed the same work as the ,watt engine with less than half of the daily coal4 ,this large economy led to orders for many engines1 on his promise that they should cost much less than those of ,watt of equal power1 and should perform the work with one-third of the coal4 ,some believed him1 though others were stony-hearted1 and as obstinate as donkeys4 ,rough draft4 ,,mr4 ,,phillip1 ,,penzance1 #hth ,march1 #ahaf4 ,sir1--,i long since expected to have heard from you that my agreement with the ,herland adventurers was executed4 ,i have in every respect fulfilled my part of the engagement with the adventurers1 and expect that they will do the same with me4 ,the engine continues to work well4 ,every person that has seen it1 except ,joseph ,price1 ,a4 ,vivian1 ,woolf1 and a few other such like beasts1 agrees that it is by far the best engine ever erected4 ,its performance tells its effects1 in spite of all false reports4 ,joseph ,price and ,a4 ,vivian reported that the engine was good for nothing1 that it would not do four millions1 and that at the next ,tuesday meeting they would turn it idle4 ,on the evening before the meeting they met at ,camborne for that purpose4 ,captain ,a4 ,vivian did not attend the meeting4 ,i could not help at the meeting threatening to horsewhip ,j4 ,price for the falsehoods that he with the others had reported4 ,i hear that he is to go to ,london to meet the ,london committee on ,monday4 ,i hope the committee will consider ,j4 ,price's report as from a disappointed man4 ,it is reported that he has bought very largely in ,woolf's patent1 which now is not worth a farthing1 besides losing the making my castings1 which galls him very sorely4 ,the water sinks regularly #bj fathoms per month1 including every stoppage4 ,on ,monday next ,i expect they will be putting down the second lift4 ,the water rises about #h inches per hour when the engine is idle1 and when at work will sink it again at the same rate1 showing that the engine is equal to double the growing stream4 ,when drawing from the pool the sinking is not much above #d inches per hour1 which shows that the water drains from a great distance from the country4 ,the engine is going fourteen strokes per minute1 #aj-;feet stroke1 #ad-a_/b-;inch box4 ,when ,herland worked last they drew a #ad-;inch box1 #g-;feet stroke1 twelve strokes per minute in winter1 and seven strokes per minute in summer4 ,therefore it appears that the winter water is about from seven to eight strokes per minute1 and the summer water from four to five strokes per minute for this engine4 ,the engine has forked faster the last week than she did before4 ,i think that the great quantity of water that was laying round the mine at the surface is nearly drawn down1 and that as we get down to a closer ground the drainage will not be so much4 ,if we have dry weather the water will1 at the next shallow level1 fall off two strokes per minute before the next lift is in fork4 ,if it continues the same we can continue to sink #bj fathoms per month1 exclusive of the time it will take to fix the lifts4 ,as we get down the house of water will lessen considerably4 ,the expense of the engine is about #ajjl4 per month4 ,the sumpmen and others attending on the forking the water1 about #ajjl4 per month more4 ,they have all the materials on the mine for the pit-work1 therefore a very trifling sum will bring the water down to the #fj-;fathom level1 when the mine will pay her own expense4 ,i will thank you for an account of the meeting4 ,your obedient servant1 ,r4 ,,trevithick4 ,mr4 ,phillip was the financial managing shareholder--more particularly with the ,londoners--at that resuscitation of ,herland ,mine2 and though the new engine was comparatively cheap1 both in its first cost and in its consumption of coal1 and satisfactorily reduced the water in the mine1 payment for it was withheld because the currents of self-interest were against ,trevithick4 ,mr4 ,joseph ,price was the manager of a steam-engine manufactory at ,neath ,abbey1 in ,south ,wales1 and had been in the habit of supplying castings for ,cornish mines4 ,arthur ,woolf was then striving to bring into use his patent double-cylinder engine1 and patent high-pressure steam-boiler1 which ,trevithick looked on as copies from ,hornblower and himself4 ,this1 added to ,woolf's sarcastic manner of speech1 roused ,trevithick's anger4 ,putting aside the words of the disputants1 the fact is stated that the pole-engine1 with a reduced steam pressure1 worked a pump #ad-a_/b inches in diameter1 #aj-;feet stroke1 fourteen strokes per minute2 while the largest and best engine by ,watt in ,cornwall1 placed on the same mine1 with a #gb-;inch steam-cylinder1 gave motion to a pump of #ad inches in diameter1 #g-;feet stroke1 at twelve strokes a minute2 being in round numbers just one-half the amount of the work performed by ,trevithick's comparatively small engine1 which had not a single feature of the ,watt engine in it4 ,rough draft4 ,,captain ,,joe ,,odgers1 ,,penzance1 ,march #g1 #ahaf4 ,sir1--,i have your favour of the #bgth ,february1 and requested ,mr4 ,page to send to you a sketch of the agreement4 ,on seeing him yesterday1 ,i found that he had neglected to send it to you4 ,he will leave the country for ,london in a few days1 and intends to call on you at ,dolley's as soon as he arrives4 ,i do not know that the agreement matters much for a few days up or down4 ,the terms are well understood between us1 which is that the adventurers and ,i equally share the advantages that may arise from this new engine over ,boulton and ,watt's4 ,when you have fully arranged with your adventurers about the engine1 please to write me1 and ,i will immediately proceed to order the engine2 and in the interim the agreement will be drawn up by ,mr4 ,page1 and executed either here or in ,london1 just as may suit4 ,i remain1 c41 ,r4 ,,trevithick4 ,p4,s4--,herland engine goes on better and better4 ,your adventurers will get a satisfactory account by applying in town to ,mr4 ,wm4 ,phillip1 ,no4 #b1 ,george ,yard1 ,lombard ,street4 ,he is the principal of the ,london adventurers4 ,trevithick believed that mine adventurers would agree to pay him one-half the saving caused by his engines1 as compared with the cost of fuel in the ,watt engine4 ,the duty performed by the latter was understood and agreed to generally2 persons were chosen by the adventurers to experiment and report on the duty of ,trevithick's pole-engine1 that the amount of payment might be ascertained in proportion to the saving effected4 ,,mr4 ,,giddy1 ,,penzance1 ,april #b1 #ahaf4 ,sir1--,i have long wished to write to you about the ,herland engine1 but first wished to see the engine loaded with a second lift1 and a trial made of the duty4 ,yesterday was fixed on1 before ordering another engine for the eastern shaft4 ,the persons attended4 ,the arbitrators gave the duty as forty-eight millions1 and said they had no doubt the engine would perform above sixty millions before getting to the bottom of the mine4 ,they were much within the duty1 but ,i did not contend with them1 as they said it was quite duty enough4 ,the engine worked #i-a_/d strokes per minute1 with #b bushels of coal per hour for the whole time1 #aj-;feet stroke4 ,there were two pump-lifts of #ad-a_/b-;inch bucket1 making #dc fathoms1 and #bf fathoms of #f-;inch for house-water4 ,the steam was from #ajj to #abj lbs4 to the inch4 ,the valve open while the plunger-pole ascended #bj inches1 then went the remainder of the #aj-;feet stroke expansive4 ,it went exceedingly smooth and regular4 ,some time since1 by way of trying the power of the engine1 we disengaged the balance-bob4 ,the engine worked twenty strokes per minute1 with #ag tons of rods1 c41 and drew #ad-a_/b-;inch bucket #bc-a_/b fathoms1 and a #f-;inch bucket #bf fathoms1 #aj-;feet stroke1 twenty strokes per minute4 ,this was about #de1jjj lbs4 weight1 with the speed of #bjj feet per minute1 which makes the duty performed more than the power of three #gb-;inch cylinders1 single1 of ,boulton and ,watt1 say of #h-;feet stroke1 #aj lbs4 to the inch1 nine strokes per minute1 which is more than these engines will perform4 ,i have all the orders for every engine now required in the country1 which is not to be wondered at1 for one-tenth part of the expense in the erection will do1 and the duty is not less than three times as much as other engines4 ,this will be proved before we get to the bottom4 ,the engine now works at about two-fifths of the load which she will have when at the bottom4 ,when the next lift is in fork ,i will write to you again4 ,i am1 ,sir1 your humble servant1 ,,richard ,,trevithick4 ,independent examiners reported that the ,herland pole-engine did forty-eight millions of duty1 under various pressures of steam1 up to #abj lbs4 to the inch1 working five-sixths of the stroke expansively1 with a speed of twenty strokes a minute1 or double the speed of the ,watt engine2 and the importance of those facts deserves the scrutiny and close study of youthful engineers4 ,a small cheap engine1 of #cc-;inch cylinder1 similar in general construction to the ,wheal ,prosper pole-engine1 but still more simple from the absence of air-pump and condenser1 did as much work as three of ,watt's largest engines with cylinders of #gb inches in diameter4 ,this great stride in the useful value of the steam-engine was forced on the public by ,trevithick's single-handed energy1 when every man was against him1 even ,henry ,harvey1 his brother-in-law and friend1 his former partner1 ,andrew ,vivian1 and his once carpenter and assistant1 ,arthur ,woolf4 ,as a closing attempt to finally crush him1 he was made personally responsible for the payment of an engine erected for the benefit of others4 ,this was the great trial test of the power and economy of the purely high-pressure expansive steam-engine as compared with the ,watt low-pressure vacuum engine applied to large pumps4 ,,sir1 ,,hayle ,,foundry1 #ahth ,april1 #ahaf4 ,i was at ,herland to-day4 ,captain ,grose received a letter while ,i was there1 signed by ,captain ,william ,davey and ,joseph ,vivian1 requesting him to appoint others to attend the trial of the engine1 as it would not be convenient for them to do it4 ,captain ,samuel ,grose1 jun41 brought down the drawing for your engine4 ,he said he had taken off the working gear only4 ,if you would wish it1 we will make the working-gear and all the wrought-iron work on the drawing for the two engines ordered1 and will take on a man or two immediately for that purpose4 ,you will let me know about this before you set off1 and also if any alteration is to be made in the beam for ,wheal ,treasure engine1 since you have altered the size of the pole4 ,we had cast the case1 but ,i suppose it will suit some place else4 ,your obedient servant1 ,,henry ,,harvey4 ,,mr4 ,,richard ,,trevithick4 ,about #ahae or #ahaf ,i was employed by ,captain ,trevithick to erect various pole-engines1 one of them at ,saltram ,stream4 ,it had worked at ,tavistock2 it was a horizontal high-pressure pole puffer4 ,captain ,samuel ,grose was then erecting for ,captain ,trevithick a #bd-;inch high-pressure pole-engine at ,beeralstone1 on the ,tamar1 to drain a lead mine4 ,i assisted ,captain ,grose4 ,the stroke was about #h feet4 ,it worked with cross-head and side rods4 ,there were two wrought-iron boilers about #c feet #f inches in diameter and #dj feet long4 ,the fire and flues were outside4 ,the steam pressure1 #fj lbs4 to the inch4 ,i also erected a similar engine with a #bj-;inch pole at ,wheal ,treasure1 now called ,fowey ,consols ,mine2 and one at ,logassack1 near ,padstow4 ,those two had brass poles4 ,it was found that the poles cut and wore in their passage through the stuffing box1 the middle wearing more than the ends1 causing steam to escape4 ,a similar pole of ,captain ,trevithick's erecting was then working at ,wheal ,regent1 near ,st4 ,austell4 ,in #ahah ,i saw working at ,wheal ,chance ,mine1 near ,scorrier1 an old #fj-;inch cylinder ,boulton and ,watt engine4 ,a pole of ,trevithick's was fixed between the cylinder and the centre of the main beam4 ,high-pressure steam was first worked under the pole and then expanded in the cylinder4#ce ,footnote #ce3 ,recollections of ,captain ,h4 ,a4 ,artha1 ,penzance1 #ahgj4 ,the late ,mr4 ,william ,burral1 for many years manager of the boiler-making department at ,messrs4 ,harvey and ,co41 at ,hayle1 said3-- ,about the year #ahae or #ahaf ,i helped to erect at ,treskerby ,mine an engine for ,captain ,trevithick4 ,mr4 ,sims was the engineer of the mine4 ,the engine had the usual cylinder1 and close to it one of ,captain ,trevithick's poles was fixed4 ,the boilers were ,captain ,trevithick's high-pressure4 ,the steam was first turned on under the pole4 ,when she had finished her up-stroke the steam passed from under the pole on to the top of the piston in the cylinder4 ,there was a vacuum under the piston4 ,the steam-cylinder was #eh inches in diameter1 about #i or #aj feet stroke4 ,the pole was #cf inches in diameter1 and a less stroke than the piston1 because it was fixed inside the cylinder1 nearer to the centre of the beam4 ,there was a pole-engine then working at ,wheal ,lushington1 also at ,poldice1 and at ,wheal ,damsel4 ,captain ,artha recollects at ,wheal ,alfred ,mine in #ahab the #ff-;inch cylinder pumping engine used a pole air-pump2 one or two whim-engines on the same mine also used them4 ,wheal ,concord pumping engine1 in #ahbg had a similar air-pump4 ,old ,wheal ,damsel1 near ,treloweth1 used one as late as #ahfe4 ,the condensing water and air passed through a branch with a valve on it near the top of the pole-case1 just under the stuffing box ,there was a foot-valve at the bottom of the pole-case4#cf ,footnote #cf3 ,captain ,artha became the resident engineer at the ,real del ,monte mines in ,mexico2 ,captain ,samuel ,grose1 one of the first ,cornish mine engineers2 and ,mr4 ,burral1 the engineer of a department at the engine-works of ,messrs4 ,harvey and ,co4 ,the writer has had the pleasure of personal acquaintance with each of those three gentlemen1 who as young engineers commenced their labours in the erection of ,trevithick's engines4 ,no sooner had ,trevithick perfected the pole condensing engine and then the pole puffer-engine1 than he1 in conjunction with ,sims1 who had just taken part in the erection of one of his high-pressure steam pole-engines for working the pumps at ,beeralstone ,mine1 combined the pole with the ordinary ,watt vacuum engines1 supplying them with steam from his high-pressure boilers1 in other words1 converting them from their original form of low-pressure vacuum engines to high-pressure expansive compound steam-engines4 ,the old #fj-;inch cylinder ,boulton and ,watt engine1 at ,wheal ,chance 7one of ,watt's favourite engines71 was in #ahah transformed into a high-pressure engine1 with ,trevithick's pole placed between the centre of the main beam and the steam-cylinder4 ,the high-pressure steam from ,trevithick's new boilers was turned under the pole for the up-stroke1 after which it was expanded in the old and much larger cylinder on the top of the piston causing the down-stroke2 it then1 by its passage through the equilibrium valve1 allowed the piston in the large cylinder to make its up-stroke1 by equalizing the pressure of steam on its top and bottom1 while a fresh supply of strong steam from the boiler admitted under the pole gave power to the up-stroke2 and finally1 the comparatively low-pressure steam under the large piston passed to the condenser and air-pump to form a vacuum for the down-stroke1 as in the ,watt engine4 ,sims1 the engineer at ,wheal ,chance1 one of the mines in the eastern or ,watt district1 was converted and became in #ahae or #ahaf a partner with ,trevithick1 and erected1 at ,treskerby ,mine1 ,trevithick's high-pressure pole of #cf inches in diameter1 as an addition to the old ,watt engine working with a cylinder #eh inches in diameter4 ,watt1 then1 within a year or two of his death1 was too old to any longer take part in the contest2 his engine in the hands of others was converted and became a high-pressure expansive engine4 ,trevithick1 as a further proof that he could do without the ,watt patent air-pump bucket1 with its piston and valves1 removed it from a ,watt engine at ,wheal ,alfred ,mine in #ahab1 replacing it by one of his poles1 answering the same purpose1 but different in construction4 ,many other mines used them2 one remained at work in ,old ,wheal ,damsel in #ahfj4 ,they have also been used in steamboat air-pumps4 ,having traced during a period of five or six years the rise and progress of the high-pressure expansive pole condensing-engines1 the high-pressure expansive pole puffer-engine1 and the combined pole and cylinder high-pressure engine1 their value in a commercial sense may be further tested by the public acts of the time4 ,lean1 an authority on such matters1 and certainly not given to unduly praise ,trevithick1 spoke as follows on the duty of those particular engines at various periods2 and not the least noteworthy is the fact1 that ,herland1 ,poldice1 and ,treskerby1 that were prominent in the early use of the ,watt engine1 threw off their allegiance but shortly before the last days of the great engineer1 and converted his low-pressure steam vacuum engines into ,trevithick high-pressures4 ,in #agih ,messrs4 ,boulton and ,watt1 who on a visit to ,cornwall1 came to see it--'the ,herland engine'--and had many experiments tried to ascertain its duty2 it was under the care of ,mr4 ,murdoch1 their agent in the county4 ,captain ,john ,davey1 the manager of the mine1 used to state that it usually did twenty millions1 and that ,mr4 ,watt1 at the time he inspected it1 pronounced it perfect1 and that further improvement could not be expected4 ,in #ahaa the average duty of the three engines 7,boulton and ,watt's7 on ,wheal ,alfred ,mine was about twenty millions4 ,these engines were at that time reckoned the best in the county4 ,in #ahaf ,sims erected an engine at ,wheal ,chance1 to which he applied the pole adopted by ,trevithick in his high-pressure engine4 ,this engine attained to forty-five millions2 and in #ahag it did #dfi millions4 ,in #ahad ,treskerby engine is reported as doing #agdh millions4--,wm4 ,sims1 engineer4 ,in #ahbj ,treskerby engine1 to which ,trevithick's high-pressure pole had been adapted1 had reached #djc millions4#cg ,footnote #cg3 ,lean's ',historical ,account of the ,steam-,engine in ,cornwall1' pp4 #aa1 #cb1 #cf4 ,the ,herland engine of ,watt in #agih did twenty millions2 in #ahaf ,trevithick's high-pressure pole puffer in the same mine did forty-eight millions4 ,in #ahbj his high-pressure pole-engine was combined with a ,watt low-pressure engine1 thereby more than doubling its economical duty4 ,in #ahac ,trevithick wrote3-- ,that new engine you saw near the sea-side with me 7,wheal ,prosper high-pressure pole condensing engine7 is now lifting forty millions one foot high1 with a bushel of coal1 which is nearly double the duty that is done by any other engine in the county4 ,a few days since ,i altered a #fj-;inch cylinder engine at ,wheal ,alfred to the same plan1 and ,i think she will do equally as much duty4 ,i have a notice to attend a mine meeting1 to erect a new engine equal in power to a #fc-;inch cylinder single4#ch ,footnote #ch3 ,see ,trevithick's letter1 ,january1 #ahac1 vol4 ii41 p4 #ee4 ,in the four or five years from his return to ,cornwall in #ahaj1 to his leaving for ,south ,america in #ahaf1 he doubled the duty and the power of the steam-engine4 ,watt once said he had received an oblique look from ,trevithick1 sen4 ,the time was now come for ,trevithick1 jun41 to return the compliment2 his improved engines having made their way into the eastern mine district1 which ,watt once looked upon as his own4 ,trevithick was short of money and on the point of leaving ,england for ,south ,america1 when ,mr4 ,sims1 in the employ of ,messrs4 ,williams and ,co41 favourable to low pressure1 was sent to negotiate for the purchase of a share in ,trevithick's patent of #ahae for the high-pressure steam expansive pole-engine4 #ahth ,october1 #ahaf4--;,agreement between ,trevithick and ,mr4 ,william ,sims1 prepared by myself and ,mr4 ,day1 solicitor for ,mr4 ,sims1 or for ,mr4 ,michael ,williams1 under whom ,sims acted1 recites1 that in consideration of #bjjl4 paid by ,sims1 he was to have a moiety of the patent for ,cornwall and ,devon1 and that ,i should have power to act and make contracts whilst ,trevithick was out of ,england4 ,the day after contract signed1 ,trevithick sailed in the ',asp1' ,captain ,kenny1 for ,south ,america4 ,i was on board when the ship sailed4 ,i see among my papers1 in ,may1 #ahai1 in reference to the patent1 is the following note3--',mr4 ,michael ,williams said it was verbally agreed that ,captain ,trevithick should have one-quarter part of the savings above twenty-six millions4' ,this1 ,i believe1 was the average duty of the engines at that time4 ,i had several assurances relative to ,trevithick's claims1 and much correspondence1 but no allowance was made from any mines but ,treskerby and ,wheal ,chance2 though ,trevithick's patent and boilers were used throughout the county without acknowledgment2 and the duty of the engines had soon increased from twenty-six millions to about seventy millions4 ,in #ahai ,i attended at the account-houses of ,treskerby and ,wheal ,chance1 of which the late ,mr4 ,john ,williams1 of ,scorrier1 was the manager1 in consequence of some of the adventurers objecting to continue the allowances on the savings to ,captain ,trevithick1 when ,mr4 ,williams warmly observed1 that whatever other mines might do1 he would insist1 as long as he was manager for ,treskerby and ,wheal ,chance1 the agreement made should be carried into effect4 ,i remain1 my dear ,thomas1 ,your very affectionate father1 ,,rd4 ,,edmonds4#ci ,footnote #ci3 ,portion of a letter written at ,penzance1 #hth ,february1 #ahec4 ,the agreement with ,mr4 ,sims1 or rather with ,mr4 ,michael ,williams1 late ,m4,p4 for ,cornwall1 who exercised large authority in ,cornish mines1 was that he should have for #bjjl4 one-half of the patent for the high-pressure pole-engine1 as applied to ,cornwall and ,devon4 ,trevithick had desisted from securing a patent for the large high-pressure steam-boilers and expansive working1 on a verbal understanding that he should receive one quarter of the saving from the reduced consumption of coal by those two particular inventions1 twenty-six millions of pounds of water raised one foot high by a bushel of coal of #hd lbs41 being the duty of the best ,watt engines1 to be taken as a starting-point for the payment4 ,treskerby and ,wheal ,chance paid for the pole-engine1 but the ,trevithick boilers suitable for high steam1 and the simple methods of working it expansively1 had been made so generally public1 that people professed to think they had a right to them1 when but a few years before they had thrown the inventor off his guard by saying everybody knows that the ,cornish boiler is your plan1 and as it cannot be denied1 a patent will be of no service4 ,mr4 ,john ,williams#dj stated that whatever other mines might do1 he would insist1 as long as he was manager for ,treskerby and ,wheal ,chance1 the agreement made should be carried into effect4 ,the ,williamses paid to ,trevithick #cjjl4 for the saving of coal by the pole patent engine1 as an acknowledgment of the benefits received by us in our mines2 but no payment was made for the greater invention of the high-pressure steam-boilers then in general use4 ,footnote #dj3 ,mr4 ,john ,williams had the remarkable dream1 many hours before the event1 enabling him to describe the particulars of the assassination of ,perceval in #ahab4 ,in #ahad the ,watt ,treskerby engine did seventeen and a half millions4 ,trevithick's boiler and pole were applied1 and the duty was increased to more than forty millions4 ,in #ahaf the same changes were made in ,wheal ,chance1 and the duty rose to more than forty-six millions4 ,the consumption of coal was reduced to one-half1 amounting in round numbers to a gain of #ejjl4 a month in those two mines alone4 _/ ,,trevince1 near ,,truro1 ,,dear ,,sir1 #eth ,january1 #ahec4 ,i am favoured with your letter of the #cast ult41 enclosing also one from ,mr4 ,f4 ,trevithick1 of the #bdth idem1 and have much pleasure in complying with your joint request to the best of my ability4 ,i was well acquainted with the late ,mr4 ,rd4 ,trevithick1 having had frequent occasion to meet him on business and to consult him professionally2 and ,i am gratified in having the present opportunity of bearing testimony to his distinguished abilities1 and to the high estimation in which the first ,cornish engineers of the day then regarded him4 ,i need scarcely say that time has not lessened the desire in this county especially to do him justice4 ,as a man of inventive mechanical genius1 few1 if any1 have surpassed him1 and ,cornwall may well be proud of so illustrious a son4 ,at this distance of time ,i can scarcely speak with sufficient exactness for your purpose of the numerous ingenious and valuable mechanical contrivances for which we are indebted to him1 but in reference to his great improvements in the steam-engine ,i have a more particular recollection1 and can confidently affirm that he was the first to introduce the high-pressure principle of working1 thus establishing a way to the present high state of efficiency of the steam-engine1 and forming a new era in the history of steam-power4 ,to the use of high-pressure steam1 in conjunction with the cylindrical boiler1 also invented by ,mr4 ,trevithick1 ,i have no hesitation in saying that the greatly-increased duty of our ,cornish pumping engines1 since the time of ,watt1 is mainly owing2 and when it is recollected that the working power now attained amounts to double or treble that of the old ,boulton and ,watt engine1 it will be at once seen that it is impossible to over-estimate the benefit conferred1 either directly or indirectly1 by the late ,mr4 ,trevithick1 on the mines of this county4 ,the cylindrical boiler above referred to effected a saving of at least one-third in the quantity of coal previously required2 and in the year #ahab ,i remember our house at ,scorrier paying ,mr4 ,trevithick the sum of #cjjl4 as an acknowledgment of the benefits received by us in our mines from this source alone4 ,mr4 ,trevithick's subsequent absence from the county1 and perhaps a certain degree of laxity on his own part in the legal establishment and prosecution of his claims1 deprived him of much of the pecuniary advantage to which his labours and inventions justly entitled him2 and ,i have often expressed my opinion that he was at the same time the greatest and the worst-used man in the county4 ,amongst the minor improvements introduced by him1 it occurs to me to notice that he was the first to apply an outer casing to the cylinder1 and by this means prevent1 still further than ,watt had succeeded in doing1 the loss of heat by radiation4 ,as connected with one of the most interesting of my recollections of ,mr4 ,trevithick1 ,i must mention that ,i was present by invitation at the first trial of his locomotive engine1 intended to run upon common roads1 and of course equally applicable to train and railways4 ,this was1 ,i think1 about the year #ahjc1 and the locomotive then exhibited was the very first worked by steam-power ever constructed4 ,the great merit of establishing the practicability of so important an application of steam1 and the superiority of the high-pressure engine for this purpose1 will perhaps more than any other circumstance serve to do honour through all times to the name of ,trevithick4 ,the experiment which was made on the public road close by ,camborne was perfectly successful2 and although many improvements in the details of such description of engines have been since effected1 the leading principles of construction and arrangements are continued1 ,i believe1 with little alteration1 in the magnificent railroad-engines of the present day4 ,of his stamping engine for breaking down the black rock in the ,thames1 his river-clearing or dredging machine1 and his extensive draining operations in ,holland1 ,i can only speak in general terms1 that they were eminently successful1 and displayed1 it was considered1 the highest constructive and engineering skill4 ,as a man of enlarged views and great inventive genius1 abounding in practical ideas of the greatest utility1 and communicating them freely to others1 he could not fail of imparting a valuable impulse to the age in which he lived2 and it would be scarcely doing him justice to limit his claims as a public benefactor to the inventions now clearly traceable to him1 important and numerous as these are4 ,from my own impressions ,i may say that no one could be in his presence without being struck with the originality and richness of his mind1 and without deriving benefit from his suggestive conversation4 ,his exploits and adventures in ,south ,america1 in connection with the ,earl of ,dundonald1 then ,lord ,cochrane1 will form an interesting episode in his career2 and altogether1 ,i am of opinion that the ,biography which you have undertaken will prove highly interesting and valuable1 and ,i wish you every success in carrying it out4 ,believe me1 my dear ,sir1 ,yours very faithfully1 ,,michael ,,williams4 ,e4 ,,watkin1 ,esq41 ,london and ,north-,western ,railway1 ,euston ,station1 ,london4 ,arthur ,woolf shortly after that time 7#ahaa7 erected his double-cylinder engines in ,cornwall4 ,the late ,captain ,samuel ,grose1 when giving the writer his recollections of ,trevithick1 said3-- ,when he returned from ,london to ,cornwall1 about #ahaj or #ahaa1 he employed me to look after the erection of the ,wheal ,prosper high-pressure engine4 ,oats1 ,captain ,trevithick's head boiler-maker1 was constructing the boilers2 ,woolf came into the yard1 and examined them4 ',what do'st thee want here8' asked ,oats4 ',d--n thee1 ,i'll soon make boilers that shall turn thee out of a job6' was ,woolf's reply4 ,he was a roughish man4 ,when his brother ,henry mutinied at the ,nore1 ,woolf1 who was then working an engine in ,meux's brewery1 and had married the lady's maid1 made interest with his employer to save ,henry from being hanged at the yard-arm1 and afterwards found employ for him in ,cornwall4 ,he was but a clumsy mechanic4 ,woolf used to blow him up by saying1 ',d--n thee1 ,i wish ,i'd left thee to be hanged4' ,the writer1 who knew ,oats1 has heard him tell similar stories of the rival engineers4 ,in #ahjj1 ,woolf1 who had been a mine carpenter1 went to ,london with the first high-pressure steam-engine which ,trevithick had sent beyond the limits of ,cornwall#da--probably to ,meux's brewery1#db for he was there in #ahjc1 and in the receipt of #cjl4 a year from ,trevithick as engine-fireman4 ,from the date of ,woolf's patent in #ahjd1 his pay from ,trevithick ceased1 and with it their friendship4 ,trevithick used to say1 ,woolf is a shabby fellow4 ,footnote #da3 ,see ,trevithick's account-book1 vol4 i41 p4 #ij4 ,footnote #db3 ,captain ,john ,vivian's recollections1 vol4 i41 p4 #adb4 ,patents sprang up like mushrooms after ,trevithick had so liberally cast forth the seeds of the high-pressure engine1 making the security1 or even the form of a patent1 a doubtful matter4 ,the perfecting of expansive high-pressure engines was like the boiler1 the result of years of trial4 ,when matured in #ahaf it saved ,cornwall and the world one-half of the coal that before had been consumed in low-pressure steam-engines4 ,every engineer became1 more or less1 an expansive worker1 and ,trevithick's saving of hundreds of thousands of pounds annually to the general public1 gave to him little or no reward4 ,at the period of those high-pressure pole-engine experiments1 ,trevithick had devoted twenty years of constant labour to the improvement and extended use of the steam-engine1 causing it to assume every variety of form except that of the ,watt patent engine1 an approach to which was unusual1 as evidenced in the high-pressure steam ,kensington model of #agif1 without beam1 parallel motion1 air-pump1 or condenser1 having no one portion either in principle or detail similar to the ,watt engine1 being portable and not requiring condensing water1 with single and double cylinders1 placed vertically or horizontally4 ,having during twelve busy years constructed over a hundred high-pressure steam-engines1 scarcely any two of which were exactly alike1 he departed if possible still further from the ,watt type1 and went back apparently1 though not in reality1 to the ,newcomen engine1 simplifying it by the omission of the great bob1 and use of condensing water1 as in the nautical labourer and steamboat engine of about #ahaj1dc and the ,south ,american mine engines of #ahaf1dd which had open-top cylinders1 more like a ,newcomen than a ,watt1 but if possible even more simple and primitive-looking than the former4 ,again1 compare the thrashing engine of #ahabde with the ,newcomen of #agab3df the great and all-important difference being that one was a high-pressure steam-engine1 the other a low-pressure atmospheric engine4 ,then came the varieties of high-pressure steam pole-engines1 working very expansively either as puffers or condensers1 retaining the same dissimilarity to the ,watt engine3 and lastly1 the combination of the high-pressure pole with the ,watt patent engine1 thereby causing the old ,watt engine to do more than double the work it had done when new from the hands of the maker1 and also to perform this increase of work with a decrease in the consumption of coal4 ,footnote #dc3 ,see vol4 i41 p4 #ccf4 ,footnote #dd3 ,see chap4 xxi4 ,footnote #de3 ,vol4 ii41 p4 #cg4 ,footnote #df3 ,vol4 i41 p4 #e4 ,the following chapter will trace the adaptation of high-pressure expansive steam1 from cylindrical boilers1 to the form of pumping engine still in general use4 ,,chapter ,,xx4 ,,the ,,watt ,,and ,,the ,,trevithick ,,engines ,,at ,,dolcoath4 ,having up to #ahaf traced the progress of the steam-engine in ,cornwall through a century1 during the latter half of which ,trevithick1 sen41 and his son were among its most prominent improvers1 the latter having devoted a quarter of a century to the work1 the effect of which is shown in the skeleton outlines of a few classes of engines1 one important feature still remains for examination before a correct judgment can be formed of the events of this period and their prime movers4 ,the use of an increasing pressure of steam gave increased force and value to the improved steam-engine1 but the power of constructing engines and boilers to render the increased pressure manageable was the result of a lifetime of labour4 ,savery1 whose engine was scarcely more than a steam-boiler1 failed to control its force1 and is said to have blown the roof from over his head4 ,the mechanism of ,newcomen's engine was well arranged1 but suitable only for the working of pumps1 and its power was limited to the weight of the atmosphere1 from which it was called the atmospheric engine4 ,in #agef1 an atmospheric engine with a cylinder of #gj inches in diameter worked at the ,herland ,mine1 the only objection to which was the cost of the coal1 to lessen which several methods had been suggested for increasing the elasticity of the steam1 and reducing the size of the boiler4#dg ,footnote #dg3 ,borlase's ',natural ,history of ,cornwall4' ,in #agge ,richard ,trevithick1 sen41 removed the flat top of a ,newcomen boiler1 and substituted a semicircular top1 enabling it to contain stronger steam1 and at the same time he improved the mechanical part of the engine by finding a better resting-place for the steam-cylinder than the top of the large boiler4 ,pryce gives a drawing of this engine as the best at that time in ,cornwall4#dh ,footnote #dh3 ,see drawing1 vol4 i41 p4 #be4 ,it is known as a fact that every engine of magnitude consumes #cjjjl4 worth of coal every year4 ,the fire-place has been diminished and enlarged again4 ,the flame has been carried round from the bottom of the boiler in a spiral direction1 and conveyed through the body of the water in a tube 7one1 two1 or three7 before its arrival at the chimney4 ,some have used a double boiler1 so that fire might act on every possible point of contact1 and some have built a moorstone boiler1 heated by three tubes of flame passing through it4 ,a judicious engineer does not attempt to load his engine with a column of water heavier than #g lbs4 on each square inch of the piston4#di ,footnote #di3 ,see ,pryce's ',mineralogia ,cornubiensis1' published #aggh4 ,appendix4 ,while ,pryce's book was being printed1 ,watt in #aggg wrote of the ,cornish steam-engines3-- ,i have seen five of ,bonze's engines1 but was far from seeing the wonders promised4 ,they were #fj1 #fc1 and #gj inch cylinders at ,dolcoath and ,wheal ,chance4 ,they are said to use each about #acj bushels of coals in the twenty-four hours1 and to make about six or seven strokes per minute1 the stroke being under #f feet each4 ,they are burdened to #f1 #f-a_/b1 and #g lbs4 per inch4#ej ,footnote #ej3 ,smiles' ',lives of ,boulton and ,watt4' ,the #fc-;inch was an open-top cylinder atmospheric engine at ,dolcoath ,mine under the management of ,trevithick1 sen42 and shortly after1 in #aggg or #aggh1 ,watt's first engine was erected in ,cornwall4#ea ,footnote #ea3 ,see vol4 i41 p4 #cj4 ,in #aghc ,trevithick1 sen41 gave ,watt an order for a patent engine for ,dolcoath1 in size similar to the old ,newcomen atmospheric1 having a cylinder #fc inches in diameter1 that a working trial might be made between the rival engines4 ,the ,watt engine having a cylinder-cover1 with the patent air-pump and condenser1 was known in the county as the ,dolcoath great #fc-;inch double-acting engine4 ,three steam-engines were then at work in that mine3 ,trevithick senior's ,carloose 7then called ,bullan ,garden7 atmospheric #de-;inch cylinder1 the atmospheric #fc-;inch cylinder1 and ,watt's #fc-;inch cylinder double-acting vacuum engine2 all of which continued in operation side by side for five years until #aghh1 when for a time ,dolcoath ceased to be an active mine4 ,trevithick1 jun41 was then a boy of seventeen years4 ,after ten years of idleness and rust1 as if mourning the death of ,trevithick1 sen41 in #agih ,richard ,trevithick1 jun41 as engineer1 and ,andrew ,vivian as manager1 induced shareholders to resuscitate the old mine4 ,fire was again given to the voracious jaws of the boilers1 and the three engines recommenced their labours and their rivalries4 ,a year or two before this ,trevithick had made models of high-pressure steam-engines4 ,davies ,gilbert1 in #agif1 met him among other engineers1 giving evidence in the ,watt lawsuits1 when he mentioned his ideas of an engine to be worked solely by the force of steam4 ,watt had claimed such an engine in his patent twenty-seven years before1 but had failed to carry it into practice4 ,hornblower had tried something like it in his double-cylinder expansion engine1 but he did not use high-pressure steam1 and consequently also failed4 ,the idea1 therefore1 of expansive steam was not new1 but the useful mastery of it was4 ,savery had tried expansive steam before ,watt patented it2 the latter went to law with ,hornblower for an infringement of the idea1 when neither of them had in truth constructed an expansive steam-engine4 ,the low pressure of the steam from the boilers used by ,hornblower and ,watt did not admit of profitable expansion in the cylinder2 at its full boiler pressure it constituted but a comparatively small portion of the power of the engine3 to reduce that power by expansion was as apt to be a loss as a gain4 ,the steam-engine was still dependent for its power mainly on steam as an agent for causing the required vacuum1 until #agif1 when ,trevithick disclosed his method of constructing small cylindrical boilers and engines suitable for giving power from the strong pressure of the steam1 irrespective of vacuum4 ,lean1 who favoured ,watt rather than ,trevithick1 thus records the advent of ,watt's expansive engine3-- ,in #aggi to #aghh ,mr4 ,watt introduced the improvement of working steam expansively1 and he calculated that engines which would previously do nineteen to twenty millions would thus perform twenty-six millions2 but ,i do not find any record of this duty being performed in practice4 ,in #aghe ,boulton and ,watt had engines in ,cornwall working expansively1 as at ,wheal ,gons and ,wheal ,chance in ,camborne2 but in these the steam was not raised higher than before1 and the piston made a considerable part of the stroke therefore before the steam-valve was closed4 ,in #agih1 on account of a suit respecting their patent1 which was carrying on by ,boulton and ,watt1 an account of the duty of all the engines in ,cornwall was taken by ,davies ,gilbert1 ,esq41 and the late ,captain ,jenkin1 of ,treworgie1 and they found the average to be about seventeen millions4#eb ,footnote #eb3 ,lean's ',historical ,statement of ,steam-,engines in ,cornwall1' p4 #g4 ,one of these so-called expansive ,watt engines1 erected at ,wheal ,chance1 was converted into a real expansive engine by ,trevithick1 as described in the foregoing chapter1 by his high-pressure steam-boilers and the addition of his pole-engine4 ,the conversion of the other1 a #fc-;inch low-pressure vacuum engine at ,wheal ,gons1 will be traced in this chapter4 ,mr4 ,taylor1 who for many years took an active interest in ,cornish mining1 says3-- ,in #agih an engine at ,herland was found to be the best in the county1 and was doing twenty-seven millions1 but being so much above all others1 some error was apprehended4 ,this engine was probably the best then ever erected1 and attracted therefore the particular attention of ,messrs4 ,boulton and ,watt1 who1 on a visit to ,cornwall1 came to see it1 and had many experiments tried to ascertain its duty4 ,it was under the care of ,mr4 ,murdoch1 their agent in the county4 ,captain ,john ,davey1 the manager of the mine1 used to state that it usually did twenty millions1 and that ,mr4 ,watt1 at the time he inspected it1 pronounced it perfect1 and that further improvement could not be expected4#ec ,footnote #ec3 ',records of ,mining1' by ,john ,taylor1 ,f4,r4,s41 c41 part i41 p4 #aee2 published #ahbi4 ,this best engine from the hands of ,watt and ,murdoch in the ,herland ,mine in #agih may be taken as a ,watt stand-point1 when its usual duty was twenty millions2 and ,trevithick and ,bull erected a competing engine1 probably with an increased steam pressure1 for ,trevithick's portable high-pressure engines were at that time coming into notice2#ed but no trace remains of the result of this contest of the ,watt and the ,bull engine1 though it was one of the causes of the lawsuits4 ,footnote #ed3 ,see vol4 i41 p4 #ie4 ,in #agii ,henry ,clark worked as a rivet boy in ,dolcoath1 and carried rivets to construct ,captain ,trevithick's new boiler1 said to be the first of the kind ever made4 ,it looked like a great globe about #bj feet in diameter1 the bottom hollowed up like the bottom of a bottle2 under this the fire was placed3 a copper tube attached to this bottom went around the inside of the boiler1 and then passed out through the side of the boiler1 the outside brick flues then carrying the heat around the outside of the boiler and into the chimney4 ,captain ,trevithick's first plunger-pole lifts in ,dolcoath were put in at this time and worked by this engine4 ,glanville1 the mine carpenter1 was head man over the engines when ,captain ,trevithick was away4#ee ,footnote #ee3 ,henry ,clark's recollections in #ahfi4 ,charles ,swaine worked as a rivet boy in making ,captain ,trevithick's cylindrical wrought-iron boilers for the ,dolcoath engine4 ,several of ,captain ,trevithick's high-pressure boilers were working in the mines before that1 but not made exactly like the ,dolcoath engine boilers4 ,when ,i was a boy about the year #ahjd1 several years before ,i worked on the ,dolcoath engine boilers1 ,i carried father's dinner to the ,dolcoath smiths' shop1 where he worked1 and used to stop and watch the wood beam going up and down of ,captain ,dick's first high-pressure steam-whim4 ,she was not a puffer1 but a puffer-whim worked near by1 called the ,valley puffer4 ,at that time most of ,captain ,dick's high-pressure boilers were smallish1 cast iron outside1 and wrought-iron tube4#ef ,footnote #ef3 ,working in the ,valley smiths' shop1 in ,dolcoath ,mine1 in #ahfi4 ,in #agii1 shortly after the reopening of ,dolcoath ,mine1 ,trevithick1 jun41 selected his father's second-hand atmospheric engine of #agge1eg to further improve it by a new boiler of uniformly globular figure1 with concave circular bottom1 under which fire was placed2 it was of wrought iron1 #bd feet in diameter1 surrounded by external brick flues2 a large copper tube1 starting from the boiler bottom1 immediately over the fire1 served as an internal flue1 carrying the fire by a sweep around the interior in the water space1 and then out through the side of the boiler into the external brick flue4 ,it may be said that there was nothing new in a circular form of boiler1 or in an internal tube2 but it will be admitted that this repaired engine1 in this its third stride in the march of advancement1 made publicly known those principles which in a few years more than doubled the power1 the economy1 and the applicability of the steam-engine4 ,his patent drawing of #ahjb shows this form of boiler applied to a small portable engine1 in which1 for the sake of simplicity of structure and cheapness1 cast iron was used instead of wrought iron1 and the internal tube omitted4#eh ,footnote #eg3 ,see vol4 i41 p4 #be4 ,footnote #eh3 ,see vol4 i41 p4 #abh4 ,the full detail estimate1 from which the following items are extracted1 of the cost of alteration was written by ,trevithick1 jun41 in the book and on the page adjoining that containing the account of the former alteration and re-erection of the same engine by ,trevithick1 sen41 in #agge4 ,a #de-;inch cylinder engine1 working #bj lbs4 to the inch3-- s4 d4 ,boilers1 #h tons at #dbl4 #ccf #j #j ,iron about ditto1 #f cwt4 at #dbl4 #ab #ab #j ,castings about ditto1 #ae cwt4 at #dbs4 #ah #j #j ,safety-valve and cocks #a #j #j ,wood about bob1 #bjj ft4 at #fs4 #fj #j #j ,cast iron about ditto1 #de cwt4 at #bes4 #ef #e #j ,brass about ditto1 #fj lbs4 at #bs4 #f #j #j ,piston-rod1 #d in41 #ad ft4 long1 #eej lbs4 at #as4 #bg #aj #j ,t-piece1 #aj cwt4 at #bes4 #ab #aj #j ,cover1 and bottom1 and piston1 #ce cwt4 at #cbs4 #ef #j #j ,nozzles1 #f cwt4 at #cbs4 #i #ab #j ,steam and perpendicular pipe1 #aj cwt4 at #bes4 #ab #aj #j ,receiver1 #b ft4 #d in4 long1 and bottom1 #ae cwt4 at #bes4 #ah #ae #j ,air-pump1 bottom1 and case1 #aj cwt4 at #bes4 #ab #aj #j ,plunger1 #bb in41 #f ft4 long1 #ab cwt4 at #djs4 #bd #j #j ,force lift #e #j #j ,engineer #ff #j #j ,the term single refers to its open-top cylinder as originally erected by ,newcomen1 when it was called the ,carloose engine1 and so it remained after its re-erection in #agge1 under the name ,dolcoath new engine1 alias ,bullan ,garden2 but after the last re-erection in #agii it had a cylinder-cover1 and was called the ,shammal #de-;inch engine2 working #bj lbs4 to the inch meant the force on each inch of the piston1 including vacuum on the one side of #ad lbs4 and steam on the other side of #f lbs4 to the inch4 ,watt1 on his first visit to ,cornwall1 in #aggg1 spoke disparagingly of the ,newcomen atmospheric engines burdened to #f or #g lbs4 net to the inch4 ,fifty years later ,stuart described ,watt's engine as using steam of a somewhat higher temperature than #bab degrees1 so as to produce a pressure between #ag and #ah lbs4 on each square inch of the piston2 yet in practice1 from imperfect vacuum and friction1 it cannot raise more water per inch than would weigh about #h-a_/b lbs41#ei or an increase of net force--when compared with the ,newcomen atmospheric--of only a pound or two on the inch in the lapse of years embracing the active lifetime of ,watt4 ,the cause of this slight increase of power is so simple that it has been passed by unnoticed by very many4 ,the steam pressure in the ,newcomen atmospheric was continued unaltered in the ,watt vacuum engine4 ,trevithick constructed the first boiler and engine capable of safely and economically using the power of high-pressure steam4 ,nelson was obliged to come to close quarters1 that his shot1 propelled by weak cannon and low-pressure powder1 might penetrate wooden ships4 ,we now manufacture and control high-pressure powder1 so that #ab inches of iron armour-plates cannot resist its force2 but this knowledge has taken nearly as long in growing to perfection as did the mastery of high-pressure steam1 and its use in the much more complicated steam-engine4 ,footnote #ei3 ,stuart's ',history of the ,steam-,engine1' published #ahbd4 ,watt's engine1 as described a quarter of a century after the expiration of his patent and the advent of the high-pressure steam-engine1 still derived its gross force from #ad lbs4 of vacuum and #b or #c lbs4 of steam1 resulting in a net force of #h-a_/b lbs4 ,trevithick's engine of #agii1 which heralded the last hours of the ,watt patent authority1 and may be taken as the first distinct evidence of comparatively high-pressure steam in large ,cornish pumping engines1 derived its power from #ad lbs4 of vacuum and #f lbs4 of steam1 being together but #b or #c lbs4 on the inch more than the ,watt engine1 but its net force of #ab lbs4 to the inch was half again as much as the net force of the ,watt engine1 the increase being wholly from the steam pressure1 which was never practised by ,watt1 and which in its almost unlimited force gives the greatly increased power to modern steam-engines4 ,trevithick's estimate for a new engine of the same size as the old was #bjjjl41 but as the old one could be improved for #acjjl41 the latter course was adopted1 the wooden main beam with its segment head was retained1 a cover was added to the cylinder1 and a new piston-rod and piston2 a pole air-pump was used in lieu of the more usual ,watt air-pump bucket2 a feed-pole forced water into the boiler1--an indirect proof of increased steam pressure4 ,the new globular boiler with internal tube weighed #h tons2 the engineer's charge for carrying out the work was #ffl4 ,the use of strong steam as the prime mover of the steam-engine increased more rapidly beyond than within the limits of ,cornwall1 for in #ahjb was erected at ,coalbrookdale a high-pressure steam-puffer engine1 to which ,trevithick attached a pump which forced water through a column of upright pipes1 that the power of the engine might be accurately measured4 ,it worked with steam of from #ej to #ade lbs4 on the inch1 and wholly discarded the vacuum which had been ,watt's mainstay4 ,the boiler is #d feet diameter1 the cylinder #g inches diameter1 #c-;feet stroke4 ,the water-piston is #aj inches in diameter1 drawing and forcing #ce feet perpendicular1 equal beam4 ,i first set it off with about #ej lbs4 on the inch pressure against the steam-valve1 for the inspection of the engineers about this neighbourhood4 ,the steam continued to rise the whole of the time it worked2 it went from #ej to #ade lbs4 to the inch4 ,the engineers at this place all said that it was impossible for so small a cylinder to lift water to the top of the pumps1 and degraded the principle1 though at the same time they spoke highly in favour of the simple and well-contrived engine4 ,after they had seen the water at the pump-head1 they said that it was possible1 but that the boiler would not maintain its steam at that pressure for five minutes2 but after a short time they went off1 with a solid countenance and a silent tongue4#fj ,footnote #fj3 ,see ,trevithick's letter1 ,august #bbnd1 #ahjb1 vol4 i41 p4 #aec4 ,this high-pressure steam pumping engine in #ahjb may be taken as the first pumping engine of the puffer class using such strong steam4 ,in the spring of the following year#fa a somewhat similar engine was erected in ,london4 ,the cylinder is #aa inches in diameter1 with a #c-a_/b-;feet stroke4 ,it requires the steam at a pressure of #dj to #de lbs4 to the inch to do its work well1 working about twenty-six or twenty-seven strokes per minute4 ,it is much admired by everyone that has seen it1 and saves a considerable quantity of coal when compared with a ,boulton and ,watt4 ,mr4 ,williams1 ,mr4 ,robert ,fox1 ,mr4 ,gould1 and ,captain ,william ,davey were here1 and much liked the engine2 they gave me an order for one for ,cornwall as a specimen4 ,this particular engine was for driving machinery in a cannon manufactory4 ,a high-pressure pumping engine was at work at ,greenwich1 and some were at work in ,cornwall4 ,footnote #fa3 ,see ,trevithick's letter1 ,may #bnd1 #ahjc1 vol4 i41 p4 #aeh4 ,,penydarran1 near ,,cardiff19999,check order of these lines ,,mr4 ,,giddy1 ,october #ast1 #ahjc4 ,sir1--,in consequence of the engine bursting at ,greenwich1 ,i have been on the spot to inspect its effects4 ,i found it had burst in every direction4 ,the bottom stood whole on its seating2 it parted at the level of the chimney4 ,the boiler was cast iron1 about #a inch thick1 but some parts were nearly #a-a_/b inch2 it was a round boiler1 #f feet diameter2 the cylinder was #h inches diameter1 working double2 the bucket was #ah inches diameter1 #ba feet column1 working single1 from which you can judge the pressure required to work this engine4 ,the pressure1 it appears1 when the engine burst1 must have been very great1 for there was one piece of the boiler1 about #a inch thick and about #e cwt41 thrown upwards of #abe yards2 and from the hole it cut in the ground on its fall1 it must have been nearly perpendicular and from a very great height1 for the hole it cut was from #ab to #ah inches deep4 ,some of the bricks were thrown #bjj yards1 and not two bricks were left fast to each other1 either in the stack or round the boiler4 ,it appears the boy that had care of the engine was gone to catch eels in the foundation of the building1 and had left the care of it to one of the labourers2 this man1 seeing the engine working much faster than usual1 stopped it1 without taking off a spanner which fastened down the steam-lever1 and a short time after being idle it burst1 killed three on the spot and another died soon after of his injuries4 ,the boy returned that instant1 and was then going to take off the trig from the valve4 ,he was hurt1 but is now recovering2 he had left the engine about an hour4 ,i would be much obliged to you if you would calculate the pressure required to burst this boiler at #a inch thick1 supposing it to be a sound casting1 and what pressure it would require to throw the materials the distance ,i have before stated1 for ,boulton and ,watt have sent a letter to a gentleman of this place1 who is about to erect some of those engines1 saying that they knew the effects of strong steam long since1 and should have erected them1 but knew the risk was too great to be left to careless enginemen1 and that it was an invention of ,mr4 ,watt1 and the patent was not worth anything4 ,this letter has much encouraged the gentlemen of this neighbourhood respecting its utility2 and as to the risk of bursting1 they say it can be made quite secure4 ,i believe that ,messrs4 ,boulton and ,watt are about to do me every injury in their power1 for they have done their utmost to report the explosion1 both in the newspapers and in private letters1 very different to what it really was2 they also state that driving a carriage was their invention2 that their agent1 ,murdoch1 had made one in ,cornwall and shown it to ,captain ,andrew ,vivian1 from which ,i have been enabled to do what ,i have done4 ,i would thank you for any information that you might have collected from ,boulton and ,watt1 or from any of their agents1 respecting their even working with strong steam1 and if ,mr4 ,watt has ever stated in any of his publications the effects of it1 because if he condemns it in any of his writings1 it will clearly show from that1 that he did not know the use of it4 ,mr4 ,homfray1 of this place1 has taken me by the hand1 and will carry both the engines and the patent to the test4 ,there are several of ,boulton and ,watt's engines being taken down here1 and the new engines being erected in their place4 ,above #gjj horse-powers have been ordered at #abl4 #abs4 for each horse-power for the patent right1 and the persons that ordered them make them themselves1 without any expense to me whatever4 ,if ,i can be left quiet a short time ,i shall do well1 for the engines will far exceed those of ,boulton and ,watt4 ,the engine at ,greenwich did fourteen millions with a bushel of coals2 it was only an #h-;inch cylinder1 and worked without an expansive cock1 and under too light a load to do good duty2 also on a bad construction1 for the fly-wheel was loaded on one side1 so as to divide the power of the double engine1 and connected to the pump-rods on a very bad plan4 ,i remember that ,boulton and ,watt's #bj-;inch cylinders when on trial did not exceed ten millions2 ,i believe you have the figures in your keeping4 ,let us have the #fj-;horse power at work that is now building1 and then ,i will show what is to be done4 ,it will be loaded at #cj lbs4 to the inch on each side the piston1 it has an #h-;feet stroke with an expansive cock1 and the blowing cylinder directly over the steam-cylinder1 as free from friction as possible4 ,there was no engine stopped on account of this accident2 but ,i shall never let the fire come in contact again with the cast iron4 ,the boiler at ,greenwich was heated red hot and burnt all the joints the ,sunday before the explosion4 ,i have received a letter from a person in ,staffordshire who has a cylinder-boiler at work with the fire in it1 and he says the engine performs above all expectation2 he requests me to give him leave to build a great many more4 ,i shall put two steam-valves and a steam-gauge in future1 so that the quicksilver shall blow out in case the valve should stick1 and all the steam be discharged through the gauge4 ,a small hole will discharge a great quantity of steam at that pressure4 ,there will be a railroad-engine at work here in a fortnight2 it will go on rails not exceeding an elevation of one-fiftieth part of a perpendicular and of considerable length4 ,the cylinder is #h-a_/b inches in diameter1 to go about two and a half miles an hour2 it is to have the same velocity of the piston-rod4 ,it will weigh1 water and all complete1 within #e tons4 ,i have desired ,captain ,a4 ,vivian to wait on you to give you every information respecting ,murdoch carriage1 whether the large one at ,mr4 ,budge's foundry was to be a condensing engine or not4 ,is it possible that this engine might be burst by gas8 ,i am1 ,sir1 ,your very obedient servant1 ,,richard ,,trevithick4 ,this high-pressure puffer pumping engine at ,greenwich1 in #ahjc1 worked a pump of #ah inches in diameter4 ,the engine boy having fixed the safety-valve while he fished for eels1 caused an explosion of the boiler4 ,this was the first mishap from the use of high-pressure steam4 ,the boiler was globular1 #f feet in diameter1 and from an inch to an inch and half in thickness1 made of cast iron2 the cylinder1 of #h inches in diameter1 was partly let into and fixed on the boiler4 ,its general design is seen in the patent drawing of #ahjb1 ,fig4 #a4fb ,trevithick determined in future to use two safety-valves1 and also a safety steam-gauge4 ,at that time one of his high-pressure puffer-engines1 with a cylindrical boiler and internal tube1 was working in ,staffordshire4 ,footnote #fb3 ,see vol4 i41 p4 #abh4 ,the ,greenwich high-pressure puffer-engine did fourteen millions of duty with a bushel of coals1 #hd lbs4 ,a #fj-;horse-power engine was being built in ,wales1 with an #h-;feet stroke1 to work expansively with #cj lbs4 of steam on the inch in the boiler4 ,for a more thorough test with the low-pressure vacuum engines1 in competition1 the ,government intended to use the new engines1 and some of ,watt's engines having been removed to make room for them1 ,boulton and ,watt wrote to a gentleman who was about to order an engine from ,trevithick1 ,we knew the effects of strong steam long since1 and should have erected them1 but knew the risk was too great4 ,moreover1 it was an invention of ,mr4 ,watt's1 and the patent 7,trevithick's7 was not worth anything4 ,this admission clearly shows not only that ,watt did not make high-pressure steam-engines1 but that he did his best to prevent others from making them4 ,,mr4 ,,giddy1 ,,penydarran1 ,,cardiff1 ,january #eth1 #ahjd4 ,sir1--,i received yours a few days since1 and should have answered it sooner1 but ,i was at ,swansea for the last four weeks1 and wished to return here to give you as full an account of our proceedings as possible4 ,we have had an #h-;inch cylinder at work here by way of trial2 it worked exceedingly well a hammer of the same size as is now being worked here by an atmospheric engine #bh inches diameter1 #e-;feet stroke1 which does not master its work with greater ease than the #h-;inch cylinder4 ,the #h-;inch is now removed to ,swansea1 and is winding coals2 the baskets hold #f cwt4 of coal2 it lifts #hj yards in a minute and a quarter1 and burns #f cwt4 of coal in twenty-four hours4 ,there were twelve horses on this pit before1 lifting #hj tons of coal in the course of the twenty-four hours4 ,you may fairly state that the #h-;inch cylinder does between thirty and forty horses' work in twenty-four hours1 with #f cwt4 of coal4 ,one of ,boulton and ,watt's #ah-;inch double engine1 about half a mile from it1 lifting baskets of the same size1 and with the same velocity1 burns above three times the quantity of coal4 ,the #h-;inch engine requires the steam to be about #df or #dh lbs4 to the inch to do its work well4 ,the standers-by would not believe that such a small engine could lift a basket of coal1 but are now much pleased with it1 and have given orders for several more4 ,there will be another at work here for the same purpose in about six weeks1 a #ae-;inch cylinder1 #f-;feet stroke1 which is a great power for a winding engine4 ,mr4 ,watt says1 in a letter to ,mr4 ,homfray1 that he could not make any of his experiments in strong steam answer the purpose4 ,it is my belief that he never made any experiments of any consequence in strong steam4 ,a great number are building at different foundries4 ,mr4 ,sharratt1 a founder at ,manchester1 who has four in building1 said that he would not pay the patent right2 on giving him notice of a trial he agreed to pay the patent right4 ,i have received a letter from ,london1 saying that an engineer called ,dixon has two engines on the same plan working2 and says that he shall not pay anything to the patentee2 that the words in ,mr4 ,watt's specification are enough to indemnify him from my threats4 ,we have had three counsels' opinions on the subject1 and they all agree that the patent is good4 ,counsels ,marratt and ,gibbs principally treated on the construction of the engine1 more than on the principle2 but ,erskine was principally on the principle of the engine1 and said very little of its construction4 ,they all say the words in ,mr4 ,watt's specification will have no weight whatever against us4 ,i shall leave this place to-morrow for ,london to make inquiry into those engines1 and to get the business into court if they will contend4 ,i shall be at ,no4 #b1 ,southampton ,street1 ,strand1 and expect to be in town about five or six days1 and if you will be so good as to return here1 from ,oxford1 with me1 ,i will call on you in my journey down4 ,it is but #ej miles from ,bristol1 and not so much as #ajj miles from ,oxford1 and the coach passes very near this place4 ,there is a great deal of machinery and mining here1 which would engage your attention for a few days1 and very pleasant gentlemen about the neighbourhood4 ,if ,i had not been called to ,swansea to put up the winding engine1 the road-engine would have been at work long since1 but in my absence very little was done to it4 ,the work is all ready1 and a part of it put together4 ,if ,i could tarry four or five days longer ,i could set it to work before going to ,london4 ,they promise me that it shall be completed before my return4 ,i think there is no doubt of its being finished1 as ,i have ,frank ,bennetts here from ,cornwall about it1 and a plenty of hands to assist him4 ,i have a thousand things to relate to you1 too much for paper to contain1 therefore must request you to be so good as to go down from ,oxford with me1 and ,i will promise1 on warrant1 that the road-engine shall be finished before my return4 ,when it is set to work ,i shall return to ,cornwall4 ,i remain1 ,sir1 ,your humble servant1 ,,richard ,,trevithick4 ,in #ahjd an #h-;inch cylinder high-pressure puffer-engine1 with steam of #dh lbs4 to the inch1 worked a large hammer as well as a #bh-;inch cylinder atmospheric engine1 and more economically than a ,watt low-pressure steam vacuum engine with an #ah-;inch cylinder1 which was five times as large as the little high-pressure4 ,in consequence of this superiority those who came to witness the trial ordered several more of ,trevithick's engines1 one of which with a #ae-;inch cylinder and #f-;feet stroke was to be at work in a few weeks4 ,watt wrote to ,mr4 ,homfray that he could not make any of his experiments in strong steam answer the purpose1 and ,trevithick declared ,watt never could have tried any experiments with high steam4 ,dixon refused to pay patent right because the words of ,mr4 ,watt's specification1 in cases where cold water cannot be had in plenty1 the engines may be wrought by the force of steam only1 by discharging the steam into the open air after it has done its office1 are enough to indemnify him4 ,eminent counsel were of opinion that the words in ,watt's specification will have no weight whatever4 ,marratt and ,gibbs were inclined to rest on the difference in the construction of the two kinds of engines1 while ,erskine boldly said that the principle was different1 and he cared little for the kind of construction4 ,the admission by ,watt that he could do nothing with high steam after an experience of thirty years from the date of his patent1 shows how difficult the work was to those who had to find the way2 yet ,trevithick had several at work within a few months of his first mental sight of a steam-engine without condensing water1 fitful glimpses of which passed and repassed while he sat unobserved in the crowded law court in #agif hearing the remarks of engineers and counsel4 ,the public until now called me a scheming fellow1 but their tone is much altered4 ,an engine is ordered for the ,west ,india ,docks1 to travel itself from ship to ship1 to unload and to take up the goods to the upper floors of the storehouses4 ,boulton and ,watt have strained every nerve to get a ,bill in the ,house to stop these engines1 saying the lives of the public are endangered by them1 and ,i have no doubt they would have carried their point1 if ,mr4 ,homfray had not gone to ,london to prevent it2 in consequence of which an engineer from ,woolwich was ordered down1 and one from the ,admiralty ,office1 to inspect and make trial of the strength of the materials4#fc ,footnote #fc3 ,see ,trevithick's letter1 #bbnd ,february1 #ahjd1 vol4 i41 p4 #afa4 ,after a week or two another letter states1#fd-- ,we are preparing to get the materials ready for the experiments by the ,london engineers1 who are to be here on ,sunday next4 ,we have fixed up #bh feet of #ah-;inch pumps for the engine to lift water4 ,these engineers particularly requested that they might have a given weight lifted1 so as to be able to calculate the real duty done by a bushel of coal4 ,as they intend to make trial of the duty performed by the coal consumed1 they will state it as against the duty performed by ,boulton's great engines1 which did upward of twenty-five millions1 when their #bj-;inch cylinders1 after being put in the best order possible1 did not exceed ten millions4 ,as you were consulted on all those trials of ,boulton's engines1 your presence would have great weight with those gents1 otherwise ,i shall not have fair play4 ,let me meet them on fair grounds and ,i will soon convince them of the superiority of the ',pressure-of-steam engine4' ,footnote #fd3 ,see ,trevithick's letter1 #dth ,march1 #ahjd1 vol4 i41 p4 #aff4 ,watt left no stone unturned to prevent the use of high-pressure steam-engines1 and fortune favoured him1 for after four or five days ,trevithick again wrote3-- ,i am sorry to inform you that the experiments that were to be exhibited before the ,london gents are put off1 on account of an accident which happened to ,mr4 ,homfray4 ,i find myself much disappointed on account of the accident1 for ,i was desirous to make the engine go through its different work1 that its effect might be published as early as possible4#fe ,footnote #fe3 ,see ,trevithick's letter1 #ith ,march1 #ahjd1 vol4 i41 p4 #afh4 ,while constructing those numerous high-pressure engines for rolling mills1 winding engines1 and pumping engines1 the ,welsh and ,newcastle locomotives were being made and worked1 yet he found time to teach the people of ,stourbridge4 ,,mr4 ,,giddy1 ,,stourbridge1 ,july #eth1 #ahjd4 ,sir1--,i should have answered your letter some time since1 but waited to set two other engines to work first4 ,the great engine at ,penydarran goes on exceedingly well4 ,the engine will roll #aej tons of iron a week with #ah tons of coal4 ,the two engines of ,boulton's at ,dowlais burn #dj tons to roll #afj tons2 they are a #bd-;inch and a #bg-;inch double4 ,the engine at ,penydarran is #ah-a_/b inches1 #f-;feet stroke1 works about eighteen strokes per minute3 it requires the steam about #de lbs4 to the inch above the atmosphere4 ,i worked it expansive first1 when working the hammer1 which was a more regular load than rolling2 then with steam high enough to work twelve strokes per minute with the cock open all the stroke2 then ,i shut it off at half the stroke1 which reduced the number of strokes to ten and a half per minute1 the steam and load the same in both2 but ,i did not continue to work it expansively1 because the work in rolling is very uneven1 and the careless workmen would stop the engine when working expansive4 ,when the cylinder was full of steam the rollers could not stop it2 and as coal is not an object here1 ,mr4 ,homfray wished the engine might be worked to its full power4 ,the saving of coal would be very great by working expansively4 ,the trials we have made for several weeks past against ,boulton's engines have been by working with the cylinder full of steam4 ,the cock springs out of its seat when water gets into the cylinder1 and prevents any mischief from the velocity of the fly-wheel4 ,the tram-engine has carried two loads of #aj tons of iron to the shipping place since you left this4 ,mr4 ,hill says he will not pay the bet1 because there were some of the tram-plates in the tunnel removed so as to get the road into the middle of the arch4 ,the first objection he started was that one man should go with the engine1 without any assistance1 which ,i performed myself without help2 and now his objection is that the road is not in the same place as when the bet was made4 ,i expect ,mr4 ,homfray will be forced to take steps that will force him to pay4 ,as soon as ,i return from here there will be another trial1 and some person will be called to testify its effects1 and then ,i expect there will be a lawsuit immediately4 ,the travelling engine is now working a hammer4 ,at ,worcester last week we put a #aj-;horse engine to work in a glover's manufactory4 ,the flue from the engine is carried through the drying room and dries his leather4 ,the steam from the engine goes to take the essence out of the bark1 and also to extract the colour out of the wood for dyeing the leather4 ,then it boils the dye1 and the steam that is left is carried into his hot-house4 ,it works exceedingly well4 ,this week ,i put another to wind coals at this place1 a #aj-;horse power1 which works very well4 ,all the tradesmen are set against it2 they say that there is no carpenter or mason work about it1 and very little smith-work1 and that it will destroy their business4 ,the engineer on the spot is also against it very much4 ,i do not expect that it will be kept long at work after ,i leave it1 unless the proprietor takes care to prevent those people from doing an injury to it4 ,mr4 ,homfray was here yesterday1 but is now returned to ,penydarran4 ,i shall go from here to ,coalbrookdale4 ,there is an engine there almost ready for the ,west ,india ,docks4 ,it will be ready to send off to ,london in about four weeks4 ,it will be a very complete engine4 ,the pumps for forcing the water will be fixed on the back of the boiler4 ,it will force #ejj gallons of water #ajj feet high in a minute2 above ten times the quantity that engines worked by men can do4 ,mr4 ,homfray and myself shall be in town as soon as the castings are sent off4 ,i hope you will be there at the time4 ,if you wish to see the engines already at work in ,london1 call on ,mr4 ,david ,watson1 steam-engine maker1 ,blackfriars ,road4 ,he lives up about #ejj or #fjj yards above the bridge on the left-hand side2 you will see his name over his door4 ,if you have time to inspect those engines you will find by comparing them against ,boulton's1 doing the same work1 that there is a great saving of coal above other engines4444 ,i shall go to ,liverpool and ,manchester from here1 and again to ,coalbrookdale4 ,there are three engines at the ,dale begun1 to work with condensers1 for places where coal is scarce4 ,i think it is better to make them ourselves1 for if we do not1 some others will1 for there must be a saving of coal by condensing4 ,but with small engines1 or where coal is plentiful1 the engine would be best without it4 ,they say at the ,dale about putting two cylinders1 but ,i think one cylinder partly filled with steam would do equally as well as two cylinders4 ,that engine at ,worcester shuts off the steam at the first third of the stroke1 and works very uniformly4 ,i cannot tell what coal it burns yet1 but ,i believe it is a very small quantity4 ,i shall know in a short time what advantage will be gained by working expansive4 ,i expect it will be very considerable4 ,there are a great many engines making and ordered4 ,boulton and ,watt and several others are doing everything to destroy their credit1 but it is impossible to destroy it now that it is so well known4 ,i have not taken any of the ground at ,bristol to remove4 ,i called on them and told them it was possible to break the ground without men1 and they wish me to take a piece to clear out1 but would not set but a small piece at a time2 therefore it would be disclosing the business to no purpose4 ,they were very desirous to know the plan1 but ,i would not satisfy them1 neither will ,i unless they pay me for it in some way or other4 ,if you direct for me at the ,dale it will find me4 ,i am happy to find that you have a seat in the ,house4 ,i wish every seat was filled with such4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,trevithick fully understood the value of the expansive principle in #ahjd3 when working with steam of #de lbs4 to the inch1 the engine went at a speed of twelve strokes a minute4 ,on cutting off the steam at half-stroke1 the speed and consequent work done fell to ten and a half strokes a minute2 in other words1 the work performed by the engine fell off only one-eighth part1 while the quantity of steam and consequently of coal was reduced by one-half4 ,the principle was established1 but the application was practically incomplete from the want of heavier fly-wheels1 to give out their momentum during the latter half of the stroke1 when the expanding steam was lessening its force4 ,the saving of coal would be very great by working expansively1 but as coal is not an object here1 ,mr4 ,homfray was careless about the expansion4 ,thirty-three years after this indirect check to steam-engine economy1 the writer1 then living in the ,sirhowey ,iron ,works1 and within stone's-throw of ,mr4 ,homfray's ,works1 recommended the removal of the ,boulton and ,watt's waggon boilers1 to make room for ,trevithick's boilers1 on the plea of saving one-half the fuel1 and at the same time increasing the power of the engine1 and thereby the pressure of the blast in the iron furnaces4 ,the proprietor was careless about the saving of coal1 and was doubtful that an increased blast would increase the quantity of iron smelted4 ,the promise that the wages of one-half of the number of boiler firemen would be saved1 was understood4 ,trevithick's high-pressure boilers replaced the ,watt low-pressure1 resulting in a largely-increased quantity of iron from the greater power and pressure of blast in the furnaces1 and at one-half the expenditure of coal in the boilers3 ten men had been employed as firemen of the ,watt boilers during twenty-four hours2 with ,trevithick's boilers1 five men did the work4 ,the high-pressure puffer-engine1 with an #ah-;inch cylinder1 working with #de lbs4 of steam1 rolled as much iron as the two larger low-pressure vacuum engines of ,watt1 of #bd and #bg inch cylinders1 which together were more than three times the size of the high-pressure engine1 and cost three times as much4 ,at ,stourbridge1 as elsewhere1 everyone was against the new plan4 ,the engineer in charge did not like it1 and the carpenters1 smiths1 and masons saw the end of their occupation as engine erectors1 if there was no longer a necessity for foundations1 well-work1 c41 for condensing water1 and many other things1 necessary to complete a ,watt engine2 while the high-pressure puffer was no sooner unloaded than it was ready to work4 ,a great charm in ,trevithick's character was his freedom and largeness of view in questions of competition4 ,he was then making three engines at ,coalbrookdale1 to be worked with high-pressure steam1 combined with the ,watt air-pump and condenser2 and though smarting from the contest with his great rival1 yet wrote1 ,i think it is better to make them ourselves1 for if we do not1 some others will1 for there must be a saving of coal by condensing4 ,but with small engines1 or where coal is plentiful1 the engine would be best without it4 ,those words accurately describe the practice of the present day1 though written sixty-six years ago1 and were followed by others equally true in principle1 though varied in form to suit special requirement4 ,they say at the ,dale about putting two cylinders1 but ,i think one cylinder partly filled with steam would1 do equally as well as two cylinders4 ,these sagacious views required the untiring labour of the following twelve years to perfect and make practical1 when applied to the largest engines of the time2 which we shall now trace in the construction of a strong and economical boiler1 supplying high-pressure steam to the cylinder during only a comparatively small portion of the stroke1 completing it by expansion1 so that at its finish the steam had become of low pressure when passed to the condenser4 ,the moving parts and expansive gear were so simplified as to be applicable to the then existing low-pressure steam vacuum engines without the complication of the double cylinders of ,hornblower and ,woolf4 ,,dear ,,sir1 ,,penydarran ,,place1 ,december #bfth1 #ahjd4 ,i have been favoured with your letter1 and in answer1 respecting ,mr4 ,mitchell1 ,i am at a loss to know from your letter what kind of iron he may likely want4 ,if you will direct him to write to me1 and explain himself1 ,i will immediately reply to him and do what ,i can to assist and serve him4 ,i believe there are vessels going over frequently from ,cardiff to ,cornwall with coals1 that he might have part in cargo and the remainder in coals4 ,i am happy to give you the most satisfactory account of our ',trevithick's engine' going on well4 ,it has now been at work many months1 and is by far the best engine we have4 ,we have for weeks weighed the coal1 and knowing the work it does1 can speak with confidence4 ,its #ah inches diameter steam-cylinder consumes as near as can be #c tons of coal in twenty-four hours1 or #ah tons per week2 and in this time it rolls with ease #acj tons long weight of iron from the puddling furnaces1 at the same heat1 into bars of #c inches by about half an inch thick4 ,now1 one on ,messrs4 ,boulton and ,watt's plan1 of '#bd inches' steam-cylinder1 at our neighbouring works at ,dowlais1 employed in doing exactly the same kind of work1 consumes full as much coal1 and rolls only #ij tons in the week4 ,these being facts1 open for any person daily to see1 must convince any dispassionate man of the superiority of ',trevithick's engines1' and that the saving of fuel is nearly one-third1 besides the other advantages of saving water and grease1 which is no little4 ,the packing of the piston now gives us little or no trouble1 it goes from a fortnight to a month1 opening the top now and then to screw it down1 as it gets slack1 which should be attended to4 ,we use no grease or oil in packing the piston or working the engine1 having found blacklead mixed with water1 and poured 'a little now and then' through a hole on the top into the steam-cylinder1 suits the packing of the piston much better1 and is cheaper than anything else4 ,about #as4 worth of blacklead will last our engine a week4 ,we are now so thoroughly convinced of the superiority of these engines that ,i have just begun another of larger size4 ,the boiler is to be #bd or #bf feet long1 #g feet diameter1 fire-tube at wide end #d feet #d inches1 and at narrow end1 where it takes the chimney1 #ba inches1 steam-cylinder #bc inches diameter4 ,this boiler1 on account of the length of its tube withinside1 will1 ,i have no doubt1 get steam in proportion1 and work the engine with much less coals than our present one4 ,trevithick is at ,coalbrookdale1 ,manchester1 c41 c41 very busy1 a great number of engines being in hand in that part of the world2 and ,i think by perseverance the prejudice is wearing away very fast1 and in spite of all ,messrs4 ,boulton and ,watt's opposition1 they must and will take the lead of theirs4 ,any person now wanting engines1 must be next kin to an idiot to erect one of ,boulton's in preference to ,trevithick's4 ,i find there is a small one making near you by ,mr4 ,vivian4 ,i hope they have corresponded with ,trevithick about the proportions of it2 if they have not1 ,i shall be particularly obliged to you to desire them to do so1 for by his experience of what he has done they may be benefited1 for it would be a shocking thing to have a bad engine put up for the first time in his native county4 ,mrs4 ,homfray unites with me in best compliments1 and wishing you many happy returns of the season4 ,i remain1 dear ,sir1 ,your most obedient servant1 ,,samuel ,,homfray4 ,to ,mr4 ,davies ,giddy4 ,the evidence in this contest between the ,watt low-pressure steam vacuum engine and the ,trevithick high-pressure steam-puffer engine is in favour of the new principle2 for the steam-engine with an #ah-;inch cylinder did fifty per cent4 more work than the vacuum engine with a #bd-;inch cylinder with an equal quantity of coal1 though the latter was seventy-five per cent4 larger than the former2 and a still greater economy was expected from the larger boiler to be built1 #bf feet long1 #g feet in diameter1 with internal fire-tube #d feet #d inches diameter at the fire end1 tapering to #ba inches at the chimney end4 ,thus in #ahjd the cylindrical boiler in ,wales had nearly reached its present form1 and ,homfray thought that none but idiots would prefer the ,watt engine2 forgetting that ,trevithick's near friends and neighbours were carrying on a similar contest at ,dolcoath ,mine4 ,,penydarran ,,place1 ,january #bnd1 #ahje4 ,,mr4 ,,davies ,,giddy1 ,dear ,sir1--,i have duly received your favour enclosing a letter for ,mr4 ,trevithick1 and which ,i1 according to your desire1 forwarded to him at ,manchester1 where he now is2 and a letter directed to him1 to the care of ,mr4 ,whitehead1 ,soho ,foundry1 ,manchester1 will find him1 as he will stay a little time there1 being very busy4 ,i had lately the pleasure of writing to you1 and gave you the account of our engine working1 and the satisfaction it gives2 ,i have nothing more to add on the subject1 but that it is now at work1 going on as usual1 and ,i should be happy for you to have a sight of it4 ,we are beginning another of a larger size1 and ,i have no doubt but by making the cylindrical boiler larger1 so as to take a longer tube withinside it1 by which means the fire will spend itself before it leaves the tube to go up the chimney1 that we shall work to much better advantage in point of fuel than we do at this present one1 as this boiler is so short that a great deal of the flame of the fire goes up the chimney4 ,we are now better acquainted with the different proportions than we at first were1 for which reason ,i am anxious that one now making by ,mr4 ,vivian should be made according to the directions of ,mr4 ,trevithick4 ,i beg leave to offer you the compliments of the season1 and many happy returns1 and ,remain1 respectfully1 dear ,sir1 ,your most obedient servant1 ,,samuel ,,homfray4 ,trevithick1 always busy1 was just now doing the work of a host1 for everybody had to be taught how to make high-pressure steam-engines2 and the ,newcastle locomotive1 the ,thames steam-dredging1 and other special applications of steam-power required his presence1 especially the fight with ,watt at ,dolcoath ,mine1 where ,andrew ,vivian1 as mine manager1 was erecting a high-pressure steam-puffer whim-engine to compete with a ,watt low-pressure steam vacuum whim-engine4 ,the adventurers grumbled because ,captain ,trevithick was so often away from the mine4 ,glanville1 the mine carpenter1 the head man over the engines1 made a trial between ,trevithick's high-pressure puffer whim and ,watt's low-pressure condenser4 ,when ,captain ,trevithick heard of it1 he wrote down from ,london that he would bet ,glanville #ejl4 that his high-pressure puffer should beat ,watt's low-pressure condenser4 ,then he came down from ,london and found that the piston of his engine was half an inch smaller in diameter than the cylinder4 ,when a new piston was put in1 she beat ,boulton and ,watt all to nothing4 ,persons were chosen to make a three or four weeks' trial1 and when it was over1 'a little pit was found with coal buried in it1 that ,glanville meant to use in the ,watt engine4'#ff ,footnote #ff3 ,recollections of ,henry ,clark1 living at ,redruth in #ahfi4 ,pooly1 ,smith1 and others1 say that ,trevithick's ,dolcoath puffer had the outer case of the boiler of cast iron1 the fire-tube of wrought iron1 the cylinder horizontal1 and fixed in the boiler4 ,captain ,joseph ,vivian saw ,trevithick's whim in ,stray ,park ,mine about #ahjj or #ahja1 and a similar one was erected in ,dolcoath1 and after a year or two a ,boulton and ,watt low-pressure whim was put up to beat it4 ,the trial was in favour of the ,watt engine1 but everybody said the agents were told beforehand which way the report ought to go2 so the engine that puffed the steam up the chimney was beaten4 ,trevithick1 who was busily engaged in ,manchester at that time1 the early part of #ahje1 when informed of what was going on in ,cornwall1 wrote3-- ,i fear that engine at ,dolcoath will be a bad one4 ,i never knew anything about its being built until you wrote to me about ,penberthy ,crofts engine1 when you mentioned it4 ,i then requested ,captain ,a4 ,vivian to inform me the particulars about it1 and ,i find that it will not be a good job4 ,i wish it never was begun4#fg ,footnote #fg3 ,see ,trevithick's letter1 ,january #ajth1 #ahje1 vol4 i41 p4 #cbd4 ,,mr4 ,,giddy1 ,,camborne1 ,february #ahth1 #ahjf4 ,sir1--,on my return from town ,i altered the pressure of the steam-engine at the bottom of the hill1 ,dolcoath4 ,before ,i returned there was a trial between mine and one of ,boulton's2 both engines in the same mine and drawing ores from the same depth4 ,the result was1 ,boulton's beat the pressure-engine as #abj to #ee4 ,since it was altered there have been three other trials2 the result was #adg to #ce in favour of the pressure of the steam-engine4 ,they are now on trial for another month1 and at the next account they intend to order a new boiler for the great engine1 and work with high-pressure steam and condenser1 provided this engine continues to do the same duty as was done in the former trials4 ,this engine is now drawing from a perpendicular shaft1 and ,boulton and ,watt's from an underlay shaft2 but to convince ,captain ,jos4 ,vivian1 we put it to draw out of the worst shaft in the mine1 and then we beat more than three to one2 we lifted in forty-seven hours1 #bcc tons of stuff #ajj fathoms with #dg bushels of coal4 ,the engine was on trial sixty-six hours1 but nineteen hours were hindered by the shaft and ropes1 c41 which made the consumption of coals about #c_/dths of a bushel per hour4 ,the fire-tube is #b feet #c inches diameter1 and the fire-bars were only #ad inches long4 ,the fire-place was but #b feet #c inches wide by #ad inches long1 and the fire about #d or #e inches thick2 it raised steam in plenty2 it was as bright as a star4 ,the engine is now doing the work of two steam-whims2 the other steam-whim in the ,valley is turned idle1 and both shafts will not more than half supply it4 #bcc tons are equal to nearly #bjjj kibbals1 which were drawn in forty-seven hours4 ,mr4 ,harris has a #ab-;inch cylinder making at ,hayle1 for ,crenver1 and ,mr4 ,daniel has a #ad-;inch for ,perran-sand1 and a great number are waiting for the trial of this month1 before altering their boilers to the great engines4 ,the steam-whim that is now turned idle at the ,valley was #ac-a_/b-;inch cylinder1 #d-;feet stroke2 it turned the whim one revolution to one stroke1 and lifted the kibbal the same height at a stroke as my engine did1 and ,i think took the same number of gallons of steam to lift a kibbal as mine did4 ,their steam was not above #d lbs4 to the inch2 mine was near #dj lbs4 to the inch2 yet ,i raised my steam of near #dj lbs4 with a third of the coals by which they got theirs of #d lbs4 to the inch4 ,this is what ,i cannot account for1 unless it is by getting the fire very small and extremely hot4 ,another advantage ,i have is1 that there is no smoke that goes off from my fire to clog the fire sides of the boiler1 while the common boilers get soot half an inch thick1 and the mud falls on the bottom of the boiler1 where the fire ought to act2 but in these new boilers the mud falls to the bottom1 where there is no fire1 and both the inside and outside of the tube are clean and exposed both to fire and water4 ,this fire-99place9999hyphenated below of #ad inches was #e feet long when ,i came down1 and then the coal did not do above one-seventh of the duty that it now does4 ,i would be very much obliged to you for your opinion on what ,i have stated1 and what advantage you think the great engine is likely to get from working with steam about #be lbs4 to the inch1 and shut off early in the stroke1 so as to have the steam about #d lbs4 to the inch when the piston is at the bottom4 ,i think this1 with the advantage of the fire-place1 will make a great saving4 ,the present fire-place is #bb feet from fire-door to fire-door1 #i feet wide1 and #g feet thick in fire4 ,there is not one-tenth of the coals that are in the fire-place on fire at the same time2 it will hold #cj tons of coals at one time1 and ,i think that a great deal of coal is destroyed by a partial heat before it takes fire4 ,a boiler on the new plan will not cost more than two-thirds of the old way1 and will last double the time1 and can be cleaned in three hours4 ,it requires twenty-four hours in the old way1 and we need to clean the boilers only one-fourth the number of times4 ,though these trials have shown so fairly that it is a great advantage1 my old acquaintances are still striving with all their might to destroy the use of it2 but facts will soon silence them4 ,i am about to enter into a contract with the ,trinity ,board for lifting up the ballast out of the bottom of the ,thames for all the shipping4 ,the first quantity stated was #cjj1jjj tons per year1 but now they state #ejj1jjj tons per year4 ,i am to do nothing but wind up the chain for #f;d4 per ton1 which is now done by men4 ,they never lift it above #be feet high4 ,a man will now get up #aj tons for #gs4 ,my engine at ,dolcoath has lifted above #ajj tons that height with #a bushel of coals4 ,i have two engines already finished for this purpose1 and shall be in town in about fifteen days to set them at work4 ,they propose to engage with me for twenty-one years4 ,the outlines of the contract they have sent me down1 which ,i think is on very fair terms4 ,i would thank you for your answer before ,i leave this county4 ,i am1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,in the trial at ,dolcoath during his absence the high-pressure steam-puffer whim was beaten by ,watt's low-pressure steam vacuum whim-engine as #ee to #abj2 but having corrected some oversight in the puffer-engine1 it then beat ,watt as #adg to #ce4 ,the trial was to be continued for a month2 and provided the superiority of his whim-engine could be maintained1 the adventurers would allow him to apply his high-pressure boilers to their large ,boulton and ,watt pumping engine4 ,the trial with the whim-engines was for the greatest number of kibbals of mineral raised to the surface by the least consumption of coal4 ,a dispute arose on the difference of the shafts1 the one causing more friction to the moving kibbal than the other1 when ,trevithick agreed to take the worst shaft in the mine4 ,on a trial during sixty-six hours ,watt's engine was beaten by more than four times2 and as ,trevithick's engine did the work that before required two engines1 one of the low-pressure steam ,watt engines was removed that the engine working with #dj lbs4 on the inch might perform the whole work4 ,my fire-tube is #b feet #c inches in diameter1 and the fire-bars only #ad inches long1 and the fire only about #d or #e inches thick2 it raised steam in plenty1 and was as bright as a star4 ,these words certainly imply the use of the blast-pipe1 making the fire as bright as a star1 and enabling the small boiler to give the required supply of steam4 ,several high-pressure puffer-engines had been ordered1 and many persons were waiting the conclusion of the month's public trial to enable them to judge between the ,watt and the ,trevithick engine4 ,,mr4 ,,giddy1 ,,camborne1 ,march #dth1 #ahjf4 ,sir1--,the day after ,i wrote to you the first letter1 ,i received yours1 and this day ,i have yours of the #ast instant4 ,i am very much obliged to you for the figures you have sent me4 ,i am convinced that the pressure of steam will not hold good as theory points it out1 because on expanding it will get colder1 and of course lose a part of its expansive force after the steam-valve shuts4 ,i think there can be no risk in making this trial on ,dolcoath great engine1 as they intend to have a new boiler immediately1 so as to prevent stopping to cleanse2 and a boiler on this new plan can be made for one-third less expense than on the old plan1 when you count the large boiler-house and ashes-pit1 and brickwork round the boiler4 ,it is not intended to alter any part of the engine or condenser1 but only work with high steam from this new boiler2 and if this boiler only performs as good duty as the old one1 it will be a saving of near #cjjl4 to them on the erection4 ,the vast matter this great engine has in motion will answer in part the use of a fly-wheel3 the whole of the matter in motion is near about #bjj tons1 at a velocity of about #afj feet a minute4 ,this ,i know will not be sufficient2 but it will be about equal to a fly-wheel of #bj feet diameter1 #be tons weight1 twenty rounds per minute1 if weight and velocity answer the same purpose4 ,since ,monday1 the #ahth ,february1 being ,dolcoath account-day1 both engines have been on trial1 and are to be continued until the next account1 #agth instant4 ,the engines are kept on in the usual way1 as at other times4 ,neither of the engines have done so much duty as on the first trials1 as they have not been so strictly attended to4 ,the average of the trial at this time stands #bf cwt4 for a bushel of coals to ,boulton and ,watt's engine2 mine1 #hc cwt4 for a bushel of coals4 ,if ,i do not remain in ,cornwall to attend next ,dolcoath account1 ,i shall be in town about the #aeth instant1 otherwise about the #bjth instant4 ,i shall call on you immediately on my arrival4 ,in this time ,i should be glad to hear from you again4 ,the ,trinity business will answer exceedingly well2 ,i have two engines ready for that purpose to put to work on my arrival in town4 ,i am1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,p4,s4--,i would try the evaporation of water by both boilers1 but ,boulton and ,watt's engine is so pressed with work1 and being on the best part of the mine1 they will not stop it a moment4 ,a boiler of #h feet diameter and #cj feet long will have as much fire-sides in the tube as there is now in ,dolcoath great boiler4 ,the fire-tube in this boiler would be #e feet diameter1 and a fire-place #f feet long in it would be #cj feet of fire-bars4 ,in the whim-engines ,i find that a fire-place #ad inches long and the tube #b feet #c inches diameter would1 being forced1 burn #a bushel per hour4 ,at this rate the great tube would burn near #ab bushels per hour1 which is above the quantity that the great engine boiler can consume1 now at work4 ,small tubes would have an advantage over large ones4 ,two boilers would not cost much more than one large one1 and be much stronger4 ,the battle-ground of the fight between low and high pressure from #ahjf to #ahab had also served for the personal encounter of ,trevithick1 sen41 and ,watt a quarter of a century before1 when the ,dolcoath great pumping engine was erected to compete with the two earlier atmospherics2 all three were still at work1 overlooked by ,carn ,brea hill and castle1 once the resort of ,druid priests1 whose sacrificial rites are still traced1 by the hollows and channels for the blood of victims on the granite rocks4 ,illustration3 ,,carn ,,brea ,,castle4 ,w4 ,j4 ,welch4 ,,mr4 ,,giddy1 ,,camborne1 ,march #bast1 #ahjf4 ,sir1--,the trial between the two engines ended last ,monday1 which was ,dolcoath day4 ,boulton and ,watt's engine1 per average of trial1 #a ton #bj cwt4 #b qrs41 with #a bushel of coals2 the other1 #e tons #aa cwt4 #c qrs41 with #a ditto1 the same depth of shaft4 ,the adventurers ordered the new castings that were made for another of ,boulton and ,watt's engines to be thrown aside1 and another new engine of mine to be built immediately4 ,the great boiler for the old engine is not yet ordered4 ,i have received orders for nine engines within these four weeks1 all for ,cornwall4 ,two #ab-;inch cylinders1 two #af-;inch ditto1 three #i-;inch ditto1 one #h-;inch ditto1 one #g-;inch ditto4 ,i expect one will be put to work next week at ,wheal ,abraham1 for lifting water4 ,this day ,i shall leave ,cornwall for ,london4 ,shall stop two days in the neighbourhood of ,tavistock1 and take orders for three engines4 ,as soon as ,i arrive in town ,i will call at your lodgings4 ,i expect that the patent will be brought into court about the end of ,may4 ,a person in ,wales owes us about #fjjl4 patent premium1 and he says that the patent is not good4 ,more particulars you shall have on my arrival4 ,the railroad is going forward4 ,i have the drawings in hand for the inclined plane4 ,i am1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,the fact that expansion of steam caused reduction of heat was so evident to ,trevithick that he ventured to doubt his friend's theory4 ,the trials between the whim-engines having continued a fortnight1 showed that the high-pressure steam-puffer had lifted #hc cwt41 while the low-pressure steam vacuum only lifted #bf cwt4 with the consumption of a bushel of coal4 ,a suitable high-pressure boiler for the ,watt low-pressure steam #fc-;inch pumping engine should be #cj feet long1 #h feet in diameter1 with an internal fire-tube #e feet in diameter2 proportions approved of in the present day4 ,the recommendation in #ahjf to use small tubes may claim to be the first practical decision on the advantage of tubular boilers2 and at the same time we read of the first hesitating step on the part of the public to use high-pressure steam in a ,watt low-pressure engine1 which was still deferred for further consideration1 even with the limited pressure of #be lbs4 to an inch2 so the large ,watt pumping engines were doomed for another four or five years to struggle through their work with low-pressure steam1 though at that time ,cook's ,kitchen high-pressure expansive condensing whim-engine had been for years at work close by4 ,the shareholders professed to have fear of explosion2 but party-feeling and ignorance were the real causes of opposition1 for working men had no dread of the new engines1 while influential men leaned toward ,watt's old-fashioned plans4 ,this fear of ,trevithick's expansive plans and high steam is the more surprising1 because at that time a new boiler was required for the ,watt #fc-;inch cylinder pumping engine and ,trevithick's cylindrical tubular boiler could be made for one-third less cost than the ,watt waggon boiler1 thus saving #cjjl41 and in addition he promised to apply the higher pressure of steam to the ,watt engine without any change in its parts or expenditure of money1 and make it set in motion at the commencement of the stroke the #bjj tons of pump-rods1 the momentum of which would1 with the expansion of the steam1 when shutting it off soon after the first start in the movement of each stroke1 carry it through to the end2 and he practically compares this advantage from hoarded momentum in the pumping engine with his experience of the fly-wheel of the rolling-mill expansive engine in ,wales4 ,the whim-engine with a fire-tube #b feet #c inches in diameter used #hd lbs4 of coal per hour2 and at that rate one cylindrical boiler #cj feet long1 #h feet in diameter1 with internal fire-tube #e feet in diameter1 would supply steam for ,watt's #fc-;inch cylinder2 but in place of it he preferred two smaller boilers1 because small tubes have an advantage over large ones1 and are much stronger4 ,the whim trials--high-pressure puffer against low-pressure vacuum--went on for another fortnight1 when high pressure1 having done twice as much work as low pressure1 with an equal consumption of coal1 the adventurers threw aside the work that had been made for another ,watt engine1 ordering one in its stead from ,trevithick2 but they could not just then make up their minds to place the ,watt #fc-;inch pumping engine in his hands4 ,,dear ,,sir1 ,,camborne1 ,may #cjth1 #ahjf4 ,i am very happy to find you have so far continued your agreement with the ,trinity gents1 and think the bargain is a good one4 ,must still beg leave to remind you not to proceed to show what your engine will do till the agreement is fully drawn up and regularly signed4 ,dolcoath agents1 since they are informed of the accident at the iron-works in ,wales1 of the engine blowing to pieces1 have requested me to have your opinion whether the old cylinder is strong enough for the boiler of the intended new engine1 or whether you would recommend them to have a new one4 ,your answer to this as soon as possible1 as ,mr4 ,williams and some others are likely to make some objections4 ,mr4 ,sims1 the engineer1 has published in the ,truro paper1 that one of ,boulton and ,watt's engines at ,wheal ,jewell has drawn more than a ton of ore over and above that drawn by the ,dolcoath engine from the same depth by a bushel of coal4 ,on inquiry ,i found they had only tried for twenty-two hours4 ,they said they left off with as good a fire as they began with4 ,this ,i argued was not a fair trial4 ,they say they are now on a trial for a month4 ,the little engine at ,wheal ,abraham does its duty extremely well4 ,the particulars as to consumption of coal cannot be fairly ascertained1 as she has never been covered1 is fed with cold water1 and has not water to draw to keep her constantly at work4 ,i wish ,i could give a better account of the mines than is in my power to give1 or of the standard price for ore1 though the latter is rather looking up than otherwise4 ,our friend1 ,north ,binner ,downs1 is better than paying cost1 but very little4 ,at present the levels are all poor2 the lode in the west shaft has underlayed faster than the shaft1 and we have not seen it for several fathoms4 ,the ground lately in the shaft has been cleaner killas1 and if any alteration1 better ground4 ,it is now #i fathoms under the #ee-;fathom level1 and we are driving to cut the lode4 ,the ground in the cross-cut is harder than when you were on the spot4 ,the water is sinking in old ,binner2 it is about #g fathoms under the adit in the western part1 and deeper in the eastern part2 we do not account for this4 ,wheal ,st4 ,aubyn combined poor4 ,wheal ,abraham looks promising1 and ,creuver about paying cost4 ,dolcoath is better than when you left us1 or when ,i was in ,london4 ,the last sale was only about #hjj tons4 ,the next sale on ,thursday is upwards of #aajj tons1 and we expect a little better standard4 ,i wish you could discover who that old gent is that wanted a large slice in ,dolcoath1 that ,i might get at him through some unknown channel1 for ,i want money sadly4 ,cook's ,kitchen continues poor1 ,tin ,croft ditto2 ,wheal ,fanny not rich4 ,we had a pretty little fight last account there with ,t4 ,kevill and ,w4 ,reynolds1 ,esquires3 black eyes and bloody noses the worst effects4 ,t4 ,kevill's face was much disfigured1 and he might have found a new road out of his coat4 ,at a meeting of ,condurrow adventurers yesterday1 twenty-four of them agreed to have one of our engines1 cylinder #ab inches in diameter and #f-;feet stroke1 provided the ,foxes do not object to it4 ,when the order is given ,i shall write to ,mr4 ,hazeldine1 provided ,i do not hear from you that it is better to send the order to any other place4 ,if you have occasion to write ,mr4 ,hazeldine1 ,i wish you would press him to hasten the engines for ,wheal ,goshen1 c4 ,i am served with a ,vice-warden's petition by ,mr4 ,harris for not working the ,weith mine in a more effectual manner1 and he prays the ,vice-warden to make the sett void4 ,the trial will come on some time the beginning of ,july1 and by that time ,i suppose we shall have two fire-engines working thereon4 ,had ,mr4 ,harvey done as he was desired we should have had one working there at this time1 but he has but now begun to do anything to it4 ,we have the cylinder and ends home from ,polgooth1 and my cousin ,simon ,vivian is making the tubes4 ,we have the other cylinder from ,wheal ,treasury1 and ,i have ordered ,horton to cast a cock for it the same as that at ,dolcoath4 ,we have cut the south lode at the adit level about #ej or #fj fathoms east of the engine1 and have driven about #bj fathoms on it4 ,it turns out about half a ton per fathom at #bjl4 a ton4 ,the ground at #djs4 per fathom2 this all in a hole1 and is better going down4 ,the back is sett to four men at #cs4 #aa;d42 their time is out this week1 and ,i suppose they must have #es4 next4 ,this may turn out a few thousands1 and ,i think too promising a thing to give up to ,mr4 ,harris4 ,i am happy to inform you that all our friends are in good health1 and beg my most respectful compliments to ,mrs4 ,rogers and adopted son2 and am1 ,dear ,sir1 ,yours very sincerely1 ,,andw4 ,,vivian4 ,the promised news respecting the engine business ,i am very anxious to have1 as it will ,i hope make me proud1 as proud ,i shall be when ,i am able to pay everyone their demands1 and have sufficient to carry on a little business to maintain my family and self without the assistance of others4 ,may you succeed in your undertaking and also be independent1 is the sincere wish of your friend4 ,john ,finnis and others are anxious to know when they will be wanted4 ,a4 ,v4 ,the explosion at ,greenwich in #ahjc was made much of1 though the fault was clearly not in the boiler4 ,three years afterwards1 in #ahjf1 a steam-cylinder burst in ,wales1 therefore ,mr4 ,williams1 a large shareholder in ,dolcoath1 objected to the use of high-pressure expansive steam in their large ,watt pumping engine1 and desired their engineer1 ,mr4 ,sims1 to make a competitive trial after his own fashion4 ,at ,condurrow ,mine one of ,trevithick's engines was to be ordered if the ,foxes and ,williamses did not object2 and so it was that ,trevithick's high-pressure steam-boiler was not ordered1 and the ,watt vacuum engine was for a longer time to receive no increase of power4 ,some of ,captain ,dick's early boilers had flattish or oval fire-tubes4 ,in #ahbj ,i repaired an old one in ,wheal ,clowance ,mine in ,gwinear4 ,the flat top had come down a little2 we put in a line of bolts1 fastening the top of the tube to the outer casing4 ,about #ahah ,i saw in ,carsize ,mine in ,gwinear a pumping engine that ,captain ,dick had put up4 ,the boiler was a cylinder of cast iron1 with a wrought-iron tube going through its length in which the fire was placed4 ,the steam-cylinder was vertical1 fixed in the boiler4 ,she had an air-pump and worked with a four-way cock4 ,the steam was about #ajj lbs4 to the inch4#fh ,footnote #fh3 ,banfield's recollections in #ahfi4 ,about #ahbj ,i removed one of ,captain ,trevithick's early high-pressure whim-engines from ,creuver and ,wheal ,abraham1 and put it as a pumping engine in ,wheal ,kitty1 where it continued at work for about fifteen years4 ,the boiler was of cast iron1 in two lengths bolted together1 about #f feet in diameter and #aj feet long4 ,at one end a piece was bolted1 into which the cylinder was fixed1 so that it had the steam and water around it4 ,there was an internal wrought-iron tube that turned back again to the fire-door end1 where the wrought-iron chimney was fixed2 the fire-grate end of the tube was about #b feet #f inches in diameter1 and tapered down to about #a foot #f inches at the chimney end4 ,it was a puffer1 working #fj lbs4 of steam to the inch2 it worked very well4 ,there were several others in the county at that time something like it4 ,it was made at the ,neath ,abbey ,works in ,wales4#fi ,footnote #fi3 ,recollections of ,captain ,g4 ,eustace1 engineer1 residing at ,hayle1 #ahfh4 ,these boilers were of the kind first tried in ,cornwall about #ahjj4 ,the oval tube in the ,kensington model of #agih continued in use in ,cornwall for many years4 ,the cast-iron outer casing was soon abandoned1 though one of them in ,wales remained in work fifty years1 using steam of #fj lbs4 to #ajj lbs4 to the inch4 ,,my ,,dear ,,jane1 ,,hayle ,,foundry1 ,august #bfth1 #ahaj4 ,i saw ,captain ,andrew ,vivian on ,wednesday1 who told me that he had been offered #aejl4 a year to inspect all the engines in the county1 and report what duty they were doing1 in order to stimulate the engineers4 ,he declined accepting it1 having too much to do already2 and he thought it would be worth ,trevithick's notice1 as it would not take him more than a day or two in a month4 ,i remain1 my dear ,jane1 ,yours sincerely1 ,h4 ,,harvey4 ,i wrote this letter on ,sunday1 with an intention of sending it then1 but thought it best to wait until this day1 in hopes of hearing the determination of ,government in your favour2 but your letter has arrived without the desired information4 ,all that ,i can now say is1 to desire that ,trevithick will make up his mind to return to ,cornwall immediately4 ,h4 ,h4 ,the application to the ,government for remuneration for benefits conferred on the public was unsuccessful4 ,the office of registrar of ,cornish engines was unsuitable2 fortunately for mining interests1 illness obliged ,trevithick to revisit his native county1 for by the increased power and economy of his engines ,dolcoath ,mine1 so frequently mentioned1 and so important in olden time1 now returns #gj1jjjl4 worth of tin yearly4 ,trevithick's first act on returning to ,cornwall in #ahaj was the erection of the high-pressure boilers and pole vacuum engine at ,wheal ,prosper2 at the same time renewing his proposals to ,dolcoath to use his improved boilers1 which had been broken off in #ahjf1 and to apply high-pressure steam to their low-pressure ,watt engine1 with the same safety and profit as in ,wheal ,prosper2 the evidence was undeniable1 so his plans were agreed to1 and in the early part of #ahaa the high-pressure boilers1 called the ,trevithick or ,cornish boilers1 were constructed in the ,dolcoath ,mine under his directions4 ,old ,john ,bryant1 who worked the ,dolcoath large engines both before and after the introduction of higher pressure steam1 including the ,carloose or ,bullan ,garden #de-;inch cylinder engine1 ,wheal ,gons #fc-;inch cylinder single engine1 and the ,watt #fc-;inch cylinder double1 with the bee-but boiler1 such as ,trevithick1 sen41 used in #agge1gj followed by the ,watt waggon boiler1 and afterwards by the globular boiler of ,trevithick1 jun41 in #agii1ga and still later also with the cylindrical boiler of #ahaa1 gave the following statement1 when seventy-four years old1 to the writer3-- ,footnote #gj3 ,see vol4 i41 p4 #be4 ,footnote #ga3 ,see vol ii41 p4 #aai4 ,in the old bee-but and the waggon boiler the steam pressure in the boiler was not much2 we did not trouble about it so long as the engines kept going3 when the steam was too high it blew off through the feed-cistern4 ,when ,captain ,trevithick tried his high steam in ,dolcoath we hoisted up the feed-cistern as high as we could2 when the steam got up1 it blew the water out of the cistern4 ,captain ,dick holloed out1 ',why don't you trig down the clack8' ,the cylindrical boilers when they were first put in leaked very much2 we could hardly keep up the fire sometimes4 ,i reckon the steam was #cj or #dj lbs4 to the inch4 ,captain ,dick's boilers made him lots of enemies4 ,i heard say in one mine where he was trying his boilers against ,boulton and ,watt's waggon1 a lot of gunpowder was put into the heap of coal4#gb ,footnote #gb3 ,old ,john ,bryant's statement in #aheh4 ,the waggon or hearse ,watt boiler was attached to his #fc-;inch cylinder double1 and the old man recollected having raised the water cistern1 when ,trevithick's globe boiler gave an increased pressure in #agii1 ten or twelve years before the cylindrical boilers were made in ,dolcoath4 ,some time after ,captain ,dick's globe boiler and steam-whims had been at work in ,dolcoath1 a letter came down from ,london1 saying that he would save the mine #ajjl4 a month if they would put in one of his new plan boilers4 ,they were put in hand in the mine1 and ,i worked about them2 they were wrought-iron cylindrical boilers1 about #bj feet long1 and #e or #f feet in diameter2 the fire-tube was about #c feet in diameter2 the fire returned around the outside in brick flues4 ,three boilers were put in side by side4 ,when ,captain ,dick first tried them1 he said to the men1 ,now mind1 the fire-bars must never have more than six inches of coal on them2 give a shovel or two to one boiler1 and then to another4 ,when ,captain ,dick's back was turned1 the men said they wasn't going to do anything of the sort1 there would never be no rest for them4 ,they used to say that the boilers saved more than #agjl4 the first month4#gc ,footnote #gc3 ,clark's recollections in #ahfi1 when he was eighty-three years old1 and resided at ,redruth4 ,clark1 when a boy1 in #agii1 helped to construct ,trevithick's globular boiler in ,dolcoath1 and recollected the events of the few following years1 during the contests with the whim-engines about #ahjf1 and the introduction of the large cylindrical wrought-iron boilers for the pumping engines in #ahaa1 and the struggle preceding the downfall of the ,watt low-pressure steam vacuum engine1 to make room for the high-pressure expansive steam-engine1 with or without vacuum4 ,about #ahab ,captain ,trevithick threw out the ,boulton and ,watt waggon boilers at ,dolcoath and put in his own1 known as ,trevithick's boiler4 ,they were about #cj feet long1 #f feet in diameter1 with a tube about #c feet #f inches in diameter going through its length4 ,there was a space of about #f inches between the bottom of the tube and the outer casing4 ,many persons opposed the new plans4 ,the ,boulton and ,watt low-pressure engine did not work well with the high steam1 and the water rose in the mine workings4 ,captain ,trevithick1 seeing that he was being swamped1 received permission from the mine managers to dismiss the old engine hands and employ his own staff4 ,captain ,jacob ,thomas was the man chosen to put things right4 ,he never left the mine until the engine worked better than ever before1 and forked the water to the bottom of the mine4 ,before that time the average duty in the county by the ,boulton and ,watt engines was seventeen or eighteen millions1 and in two or three years1 with ,trevithick's boilers and improvements in the engines1 the duty rose to forty millions4 ,about #ahbf he 7,captain ,vivian7 was manager of ,wheal ,towan2 their engines were considered the best in the county1 doing eighty-seven millions2 they had ,trevithick's boilers1 working with high-pressure steam and expansive gear2 few if any of ,boulton and ,watt's boilers could then be found in the county4 ,sir ,john ,rennie and other scientific men1 who doubted the reports of the duty1 came and made their own trials with the engines1 and were satisfied that the duty was correctly reported4 ,about that time a ,mr4 ,neville requested him to report on the engines at his colliery at ,llanelthy2 one was an atmospheric of ,newcomen's1 doing six millions2 and four or five of ,boulton and ,watt's patent engines averaged fourteen millions4#gd ,footnote #gd3 ,captain ,nicholas ,vivian was a schoolfellow and intimate friend of ,trevithick's2 he resided at ,camborne in #aheh1 when he gave his recollections4 ,when at last the cylindrical high-pressure boiler was admitted1 and men had been taught to fire them1 many persons still liked the old plans1 and among them the easy-going low-pressure enginemen4 ,the consequence was that the ,watt engines under their management refused the early doses of ,trevithick's high steam1 not easily digesting it1 and their obstinacy nearly swamped ,trevithick and his plans4 ,when a little boy1 about #ahab1 ,i frequently carried my father's dinner from ,penponds to ,dolcoath ,mine4 ,one day1 not finding him in the engine-house1 ,i sought him in the account-house1 but not knowing him in a miner's working dress1 refused to give him his dinner4 ,william ,west then worked with him4 ,i heard there was difficulty in making the new boilers and the old engine work well2 engineers from other mines looked on from a distance1 not liking the risk of explosion4 ,people seemed to be against the new plans2 some labourers worked with them4 ,this narration--sixty years after the events--from ,mr4 ,richard ,trevithick1 the eldest son of the engineer1 shows that ,william ,west helped in applying high-pressure steam to the ,watt low-pressure engine1 and that but few sympathized with the innovators on old customs2 but among them was ,captain ,jacob ,thomas1 who successfully fed the old engine with strong steam4 ,at that time the ,watt engines in ,cornwall had been doing seventeen or eighteen millions2 ,trevithick's new boilers increased their duty to forty millions4 ,william ,pooly#ge was working in ,dolcoath before ,captain ,trevithick's new boilers were put in1 and helped to put them in4 ,footnote #ge3 ,william ,pooly worked the ,dolcoath #gf-;inch engine in #ahfi2 his recollections were given in the old engine-house1 on the spot once occupied by ,watt and his #fc-;inch great double engine4 ,the ,shammal #de-;inch engine was an open-top cylinder1 with a chain to the segment-head wooden beam4 ,so was the #fc-;inch cylinder ,stray ,park engine1 then called ,wheal ,gons#gf in ,dolcoath sett1 and the ,boulton and ,watt #fc-;inch cylinder double-acting4 ,footnote #gf3 ,smiles speaks of this as ,bonze's4 ,there used to be great talking about different boilers2 a boiler of ,captain ,trevithick's worked with higher steam than the others4 ,just before ,captain ,dick came back to the mine a ,boulton and ,watt hearse boiler had been repaired with a new bottom2 it was never used4 ,i and ,william ,causan took a job to cut up the boiler at #as4 #f;d4 the hundredweight2 it weighed #ag tons4 ,jeffrie and ,gribble were the mine engineers2 ,glanville used to be considered ,captain ,dick's man in the mine4 ,you could stand upright on the fire-bars in the middle hollow of the hearse boiler1 and so you could in the outside brick flues2 the middle hollow was like a horse-shoe4 ,when ,captain ,dick put in his cylindrical boilers he altered the #fc-;inch single2 there was hardly anything of her left but the main wall1 with the wood bob and a chain to the piston-rod1 and also to the pump-rods4 ,there was an air-pump1 and ,i think a second-hand cylinder was brought1 but it was a #fc-;inch2 the old ,shammal engine had been altered1 too4 ,the new boiler put in was about #h feet in diameter and from #cj to #dj feet long1 two round tubes went through it2 the fire-place in one end of one tube and in the other end of the other tube2 after going through the tubes the draught went into the brick flues under the bottom and sides4 ,when the new engine was put in1 ,gribble said1 ,why1 these little things will never get steam enough2 everybody said so4 ,in the ,boulton and ,watt engines we didn't trouble about feed-pumps and gauge-cocks4 ,a wire came through a stuffing box in the top of the boiler2 a biggish stone in the boiler was fastened to one end of the wire1 the other end was fastened to a weighted lever near the water cistern1 just above the boiler2 when the water got low the stone opened the valve in the water cistern4 ,that was when they were putting in ,captain ,dick's new cylindrical boilers to the old #fc-;inch engine4 ,she did so much more work1 with less coal1 that in a year or so they agreed to throw out ,boulton and ,watt's engine1 and to put in a stronger one that could stand ,captain ,dick's high steam4 ,jeffrie and ,gribble were the mine engineers that put her up4 ,the #gf-;inch cylinder came from ,wales4 ,the big beam was cast at ,perran ,foundry in #ahae2 you can see the name and date upon it now4 ,the boiler and the gear-work were made in the mine4 ,the exhaust-valve is exactly as when it was put in1 worked by a rack-and-tooth segment4 ,the equilibrium valve is unchanged1 except that the rack is taken out and a link put in4 ,the steam-valve was taken out soon after she went to work1 and the present double-beat valve was put in2 it is the first of the kind ,i ever saw4 ,some were made before that time with a small valve on the top of the big one1 that opened first1 to ease the pressure4 ,john ,west#gg fitted up the valve-gear in the mine with the expansive tappets1 the same as when she stopped a month or two ago1 and the same as the present new one has4 ,footnote #gg3 ,three ,wests1 all skilful mechanical engineers1 were employed at that time in ,dolcoath1 all of them known to the writer1 who thinks the double-beat valve was the handiwork of ,john ,west1 not related to ,trevithick's partner4 ,captain ,dick's cutting off his strong steam at an early part of the stroke1 used to make the steam-valve strike very hard2 so the new plan valve1 with a double beat1 was put in2 that must have been about #ahaf or #ahag2 and the valve and expansive horn for working were just exactly like what they have put into the present new engine in #ahfi4 ,she was the engine that showed them how to fork the water1 and burn only half the coal4 ,i worked in this mine the old atmospheric engines1 and then ,boulton and ,watt2 and then ,trevithick's boilers in ,boulton and ,watt2 and then ,trevithick's boilers and engine2 and now ,i come every day to the new engine1 though ,i can't do much4 ,they give me #ces4 a month2 and my name is ,william ,pooly1 ,dolcoath1 #ahfi4 ,three years ago 7in #ahfi71 when the writer entered the old engine-house in which ,watt's #fc-;inch cylinder double had been erected in #aghj1 adjoining the old walls that then enclosed that early ,newcomen #de-;inch cylinder ,carloose engine1 re-erected by ,trevithick1 sen41 in #agge in ,bullan ,garden portion of ,dolcoath1 an old man sat near a small window in a recess in the thick wall of the engine-house1 within reach of the gear-handles of the ,jeffrie and ,gribble #gf-;inch cylinder engine that ,trevithick1 jun41 had erected in #ahaf on the foundations of the removed ,watt engine2 he held in one hand a portion of slate from the roof1 and in the other an old pocket-knife1 one-half of the blade of which had been broken off1 leaving a jagged fracture1 with which he made the figures of some calculation on the rude slate2 on his nose rested the brass frame of a pair of very ancient spectacles1 with horn glasses4 ,he answered the writer's question by1 ,yes1 ,i am ,william ,pooly2 ,i worked this engine1 and the other engines before it--the great double and the little ,shammal working out of the same shaft2 and ,i am seventy-four years of age4 ,the #fc single worked upon a shaft up there2 she was called ,wheal ,gons4 ,that old man1 still living1 had worked in ,dolcoath ,mine one of the first steam-engines of ,newcomen2 the #de-;inch1 modified by ,trevithick1 sen42 then the #fc-;inch double of ,watt2 and1 finally1 the high-pressure engines of ,trevithick1 jun42 he saw the open-top cylinders1 atmospheric of ,newcomen1 in the ,shammal #de-;inch and ,wheal ,gons #fc-;inch1 with their wooden beams with segment-headed ends1 moving in rivalry with the ,watt #fc-;inch double1 with cylinder-cover and parallel motion2 he saw the two former engines1 as altered by ,trevithick1 jun41 using the higher steam from the globular boiler on which ,henry ,clark worked in #agii1 when there used to be great talking about different boilers1 and a boiler of ,captain ,trevithick's worked with higher steam than the others2 and the waggon boiler of ,watt1 that had just been repaired1 was discarded and cut up2 thus described by ,trevithick1 the fire-place is #bb feet from fire-door to fire-door1 #i feet wide1 and #g feet thick in fire1#gh which he proposed to replace in #ahjf by a cylindrical boiler to give steam of #be lbs4 on the inch4 ,footnote #gh3 ,see ,trevithick's letter1 ,february #ahth1 #ahjf1 vol4 ii41 p4 #adc4 ,pooly also saw the finishing stroke in #ahaa1 when the boilers still known as the ,trevithick or ,cornish boilers1 gave steam to the three engines2 after a twelve years' fight between low and high pressure1 commencing with ,trevithick's globular boiler and internal tube1 in ,dolcoath1 in the year #agii1 from which time it gained step by step1 though in comparatively small engines1 up to #ahaa1 when the cylindrical boilers took the place of the condemned hearse and globular boilers1 and gave really strong and expansive steam to the three ,dolcoath pumping engines that from time immemorial had been rivals1 causing all three of them to lift an increased quantity of water1 and at the same time to save one-half in the cost of coal2 this continued for four or five years1 when in #ahaf the #fc-;inch double and the #de-;inch1 being the youngest and the oldest of the three1 were removed1 that a new #gf-;inch cylinder1 better adapted to ,trevithick's expansive steam might more cheaply perform their joint work4 ,prior to this change the three engines were known by the names ,shammal #de-;inch1 formerly ,bullan ,garden1#gi but before that as ,carloose1 of the period and form of the ,pool engine2#hj ,stray ,park #fc single1 formerly ,wheal ,gons1#ha dated from #aggj to #aggg2 and the #fc-;inch double of ,watt in #aghj4 ,footnote #gi3 ,see vol4 i41 p4 #be4 ,footnote #hj3 ,see vol4 i41 p4 #e4 ,footnote #ha3 ,query ,bonze1 spoken of by ,smiles4 ,,sir1 ,,dolcoath ,,mine1 ,march #bith1 #aheh4 ,i have obtained the following information respecting the building of the first cylindrical boilers1 as ordered by your late father for ,dolcoath2 and some information of the results as to the coals consumed1 compared with the consumption by the boilers previously in use here4 ,george ,row1 now about seventy-two years old1 and working at ,camborne ,vean ,mine1 says he assisted to build the two first cylindrical boilers with internal tubes used in ,cornwall4 ,they were built in ,dolcoath ,mine in the year #ahaa2 they were #ah feet long1 #e feet diameter1 having an oval tube #c feet #d inches in the largest diameter at the fire end2 the other or chimney end of the tube was somewhat smaller4 ,they were found too small for the work to be done1 and another boiler was built immediately1 #bb feet long1 #f feet #b inches diameter1 and he believed a #d-;feet tube4 ,john ,bryant1 now seventy-four years old1 works a steam-engine at ,west ,wheal ,francis4 ,he worked at ,dolcoath the #fc-;inch cylinder double-acting engine1 upon ,boulton and ,watt's plan4 ,when he first worked her she had the old bee-but boiler1 #bd feet in diameter4 ,they were taken out for the ,boulton and ,watt waggon boiler1 #bb feet long and #h feet wide1 with two fire-doors opposite one another4 ,then the ,boulton and ,watt waggon was taken out for ,captain ,trevithick's boilers1 which he worked for several years4 ,two boilers were put in1 each #ah feet long1 #e feet diameter1 with an internal oval tube1 he thinks1 #c feet by #b feet #f inches4 ,shortly after1 another boiler of similar form was added1 #bb feet long1 #f feet diameter1 #d-;feet tube4 ,he cannot say what the saving of coal was1 but remembers that the duty performed by the engine with the waggon boiler was thirteen to fourteen millions4 ,mr4 ,william ,west came to the mine as an engineer1 and by paying great attention increased the duty of the ,boulton and ,watt engine and boiler to about fifteen millions4 ,he does not recollect the duty the engine performed with the cylindrical boilers4 ,mr4 ,thomas ,lean1 of ,praze1 the present reporter of mine engines in the western part of ,cornwall1 in answer to a note ,i sent to him1 says he has no account of any report of ,dolcoath engines for the year #ahab1 but during the month of ,april in that year the engines did #ba-a_/b millions4 ,during the whole of #ahac that engine was reported to average a duty of twenty-one millions4 ,the whole of the above are at per bushel of #ic lbs41 and the whole of the accounts furnished by ,mr4 ,lean are for ,trevithick's cylindrical boilers4 ,from the ,dolcoath ,mine books ,i find the following3 ,paid for coals for the whole mine during the year #ahaa1 #aaejl4 #aes4 #aj;d41 or per month1 #ical4 #ads4 #g;d4 ,during the first three months of #ahab the coal averaged #ajjjl4 per month4 ,in ,may of this year1 #ahab1 ,captain ,trevithick is entered on the books as paid #djl4 on account of boilers2 and in ,august of the same year1 for erecting three boilers1 #ajel4 ,i think the three boilers were at work in ,april1 #ahab1 the month ,mr4 ,lean gives as the first reported4 ,from ,april1 #ahab1 to ,december1 during nine months1 the cost of coals was #eeabl4 #fs41 averaging #fabl4 #is4 #f;d4 per month4 ,during the next year1 #ahac1 the cost for coal was #gjail4 #ags4 #e;d41 or an average per month of #eijl4 #afs4 #e;d4 ,i cannot find the price paid per ton for the coal in these years1 but the average price during #ahjh and #ahae was much alike1 making it probable that the price per ton during #ahaa1 #ahab1 and #ahac1 was nearly the same2 and that the saving of the above #cjjl4 per month in ,dolcoath was wholly on account of the saving effected by ,trevithick's cylindrical boilers4 ,the testimony of ,john ,bryant1 that the duty with the waggon boiler was say fourteen millions1 and that of ,mr4 ,lean1 giving twenty-one millions with the new ,trevithick boiler1 bear much the same proportion as the charges for coals in the respective periods above given4 ,in the year #ahaf a new #gf-;inch single engine was erected in the place of the old ,boulton and ,watt #fc-;inch double engine with ,trevithick's cylindrical boilers4 ,the average duty performed during the year #ahag was #dc-c_/d millions4 ,this same engine is still at work1 and her regular duty is from thirty-six to thirty-eight millions4 ,i am1 ,sir1 ,your most obedient servant1 ,,charles ,,thomas4 ,,francis ,,trevithick1 ,esq4 ,captain ,charles ,thomas1 who was one of the most experienced of ,cornish miners1 for many years the manager of ,dolcoath1 and in youth the acquaintance of ,trevithick1 states that the new high-pressure boilers were made in the mine in #ahaa1 and gave their first supplies of strong steam to the three large pumping engines in ,april1 #ahab1 with such good effect that the increasing water which had threatened to drown the mine was speedily removed1 and that with a saving of nearly one-half of the coal before consumed4 ,prior to their use ,dolcoath ,mine paid #ajjjl4 monthly for coal2 but for the latter nine months of the year1 in consequence of the new boilers1 the cost was reduced to #fabl4 a month4 ,this saving in the pumping cost of one mine crowned with success the high-pressure steam engineer1 who had been steadily gaining ground during his fight of twelve or fourteen years on the battle-ground chosen by ,watt thirty-three years before4 ,the low price of tin and copper1 which caused so many engines to cease working about the close of the last century1 had changed for the better1 and the present century opened with an increasing demand for steam power4 ,trevithick's high-pressure portable engines had worked satisfactorily for several years2 and as a means of making public the relative duty performed by ,cornish pumping engines1 and of solving conflicting statements on the rival systems of low and high pressure steam1 it was determined that an intelligent person should examine and give printed monthly reports of the amount of duty done by the different engines1 and in #ahaj ,captain ,andrew ,vivian was requested to take this work of engine reporter in hand2 on his refusal it was offered to ,trevithick4 ,in ,august1 #ahaa1 ,mr4 ,lean commenced such monthly reports1 showing that the duty of twelve pumping engines at the end of that year averaged seventeen millions1 exactly the duty done by the ,boulton and ,watt engines thirteen years before1 as reported by ,davies ,gilbert and ,captain ,jenkin in #agih1 proving the small inherent vitality of the ,watt engine4 ,in #ahad the ,dolcoath pumping engines1 with ,trevithick's cylindrical boiler and high steam expansion1 are thus reported3--,the ,boulton and ,watt1 ,dolcoath great double engine1 #fc-;inch cylinder1 did a duty of #ba-a_/b millions2 the ,shammal #de-;inch cylinder1 single engine1 did #bf-c_/d millions2 and the #fc-;inch single1 ,stray ,park engine1 #cb millions4 ,shammal engine1 nearly #ajj years old1 beat the ,watt engine of more than half a century later2 and so did ,stray ,park #fc-;inch1 which ,watt had laughed at when he first tried his hand as an engineer in ,cornwall in #aggg4hb ,footnote #hb3 ,see vol4 i41 p4 #cj2 vol4 ii41 p4 #aae4 ,the marked change in these three engines1 while for two or three years under ,trevithick's guidance1 becoming more powerful and economical1 raised the usual swarm of detractors1 and in #ahae a special trial was made1 which lasted for two days1 to test the reported increased duty by the cylindrical boilers and expansive working4 ,the unbelievers were then convinced1 and agreed to throw out the ,boulton and ,watt great double engine #fc-;inch cylinder1 together with its neighbour1 the worn-out old #de-;inch1 and put in their stead one engine with a cylinder of #gf inches in diameter1 with expansive valve and gear1 and parts strong enough and suitable to the high-pressure steam1 on ,trevithick's promise that it should do more than the combined work of the other two with one-half the coal4 ,in #ahaf this new engine commenced work1 and did forty millions of duty1 increasing it during the next two or three years to forty-eight millions1 being three times the duty performed by the ,watt #fc-;inch double engine before it was supplied with steam from ,trevithick's boilers1 and twice as much as it performed when so supplied4 ,lean says1 ,this was the first instance of such duty having been performed by an engine of that simple construction4 ,the other mines followed ,trevithick's advice1 but never paid him a penny4 ,on this ,lean again says1 ,the engines at work in the county in #ahce would have consumed #hj1jjjl4 worth of coal over and above their actual consumption yearly1 but for the improvements that had been made since #ahad4 ,trevithick's engines were very durable1 as well as cheap in first cost and in working expense4 ,this famous ,dolcoath #gf-;inch engine remained in constant work night and day for fifty-four years2 after which good service the steam-pipes1 being thinned by rust1 were held together by bands and bolts2 the steam-case around the cylinder would no longer bear the pressure of steam2 the interior of the cylinder from wear was one inch larger in diameter than when first put in1 and had to be held together by strap-bolts4 ,the original boilers were said to remain1 only they had been repaired until not an original plate remained2 but there they were in the old stoke-hole in #ahfi1 when1 from the fear of some part of the engine breaking and causing accident1 it was removed4 ,illustration3 ,,trevithick',s ,,dolcoath #gf-;,,inch ,,cylinder ,,pumping ,,engine1 ,,erected ,,in #ahaf1 ,,ceased ,,working #ahfi4 a1 steam-cylinder1 #gf inches in diameter1 #i-;feet stroke2 b1 steam-jacket2 c1 steam expansion-valve1 #aa inches diameter1 double beat2 the upper beat #aa inches diameter1 the under beat #i-a_/b inches1 valve #h inches long2 d1 expansive cam on plug-rod2 e1 plug-rod for moving the gear2 f1 expansive horn2 g1 equilibrium valve1 #ac inches in diameter1 single beat moved by a tooth-rack and segment2 h1 exhaust-valve1 #ad-a_/b inches in diameter1 single beat moved by a lever and link2 i1 equilibrium-valve handle2 j1 exhaust-valve handle2 k1 ,y-posts for carrying the gear arbors2 l1 main beam in two plates of cast iron2 m1 parallel motion2 n1 feed-pump rod2 o1 air-pump bucket-rod1 the pump1 #b feet #i inches diameter2 p1 the main pump rods4 ,illustration3 ,,cylinder1 ,,main ,,beam1 ,,and ,,pump-,,rod ,,of ,,dolcoath #gf-;,,inch ,,cylinder ,,engine4 ,in #ahfg the writer was a member of the ,dolcoath ,managing ,committee1 when it was determined that the old engine of #ahaf should be replaced by a new one4 ,the cylinder sides were reduced in thickness by half an inch2 the steam-pipes and nozzles were thinned by rust and decay2 the valves and gear-work remained in good order4 ,captain ,josiah ,thomas1 the present manager of the mine1 offered to sell this old engine at scrap price1 that it might be stored in the ,patent ,museum at ,kensington as a memento of the early high-pressure expansive steam pumping engine4 ,illustration3 ,,boilers ,,erected ,,in #ahaa ,,in ,,dolcoath1 ,,used ,,in ,,the ,,boulton ,,and ,,watt #fc-;,,inch ,,engine1 ,,then ,,in ,,the ,,new #gf-;,,inch ,,until #ahfi4 a a1 two wrought-iron cylindrical boilers1 #e feet in diameter1 #ah feet long1 with internal fire-tube1 oval1 #c feet #d inches by #c feet2 b1 a boiler1 #f feet #b inches diameter1 #bb feet long1 cylindrical tube1 #d feet diameter in the fire-place1 the remainder #c feet2 c1 brick bridge2 d1 fire-bars2 e1 brick external flues under boiler2 f1 brick side-flues2 g1 ashes1 or other non-conductor2 steam #cj to #ej9999unclear lbs4 on the inch above the atmosphere4 ,the steam-cylinder of #ahaf was cast in ,south ,wales2 the beam still working in the new engine of #ahfi was cast in the foundry of the ,williams' at ,perran4 ,john ,west replaced the original flat expansive steam-valve with a double-beat valve2 the gear was principally made by him on the mine1 and remained in good working to the last4 ,this double-beat valve is the first the writer has met with2 it is of the same form as the modern double-beat valve2 an earlier plan was to have a small valve on the top of the main valve4 ,the steam in ordinary working was shut off when the piston had moved from an eighth to a quarter of its stroke4 ,the ,gons1 or ,stray ,park #fc-;inch cylinder1 survived its companions1 the #fc double1 and #de single1 for some ten or fifteen years1 having beaten both of them in duty4 ,a memorandum in ,trevithick's handwriting shows that he in #agih1 when designing his large globular boiler with internal flue at the reworking of ,dolcoath1 tested the relative duty of the ,watt #fc-;inch double and the #fc-;inch single engine1 then called ,wheal ,gons1 the latter in its original form of open-top cylinder atmospheric2 shortly after which it probably received a cover about the same time as the #de-;inch1 for both those engines were thoroughly repaired by ,trevithick at the reworking of the mine1 twelve or fourteen years prior to the use of the cylindrical boilers4 ,at the time that ,boulton and ,watt made their trial of ,seal-hole engine against ,hornblower's engine at ,tin ,croft1 the engines were put in the best order1 and good coals brought in for the purpose1 to work for twenty-four hours4 ,the trial was attended by the principal mining agents2 the result was about ten millions by each engine4 ,at ,dolcoath ,mine an old atmospheric engine continued to work for several years by the side of one of ,boulton and ,watt's engines of the same size2 the water lifted and coals consumed were carefully taken and made known to the public1 showing that ,boulton and ,watt's engine performed1 when compared with the old engine1 as #af to #aj4hc ,footnote #hc3 ,memorandum in ,trevithick's writing4 ,hornblower was an active engineer in ,cornwall before ,watt2 the patent of the latter claiming the sole right of working an engine by steam in the cylinder1#hd drove the former to use two cylinders1 in one of which the expansion was carried out1 as a means not described in ,watt's patent2 a lawsuit was the consequence4 ,the two engines when tried by ,trevithick#he performed an equal duty of ten millions4 ,in #agih he tested the ,dolcoath atmospheric #fc-;inch single against ,watt's great #fc-;inch double action4 ,the atmospheric performed ten millions1 precisely the duty of the patent ,watt and the patent ,hornblower contests of six years before2 but the ,watt ,dolcoath engine1 then considered the best he had made1 did sixteen millions4 ,these trials in #agib and #agih enable us to compare the ,newcomen1 the ,hornblower1 and the ,watt engines2 shortly after which ,trevithick tried higher steam in one or more of those same engines from his globular boiler4#hf ,footnote #hd3 ,see vol4 i41 p4 #df4 ,footnote #he3 ,see vol4 i41 p4 #eg4 ,footnote #hf3 ,see vol4 ii1 p4 #aai4 ,,sir ,,ch4 ,,hawkins1 ,,camborne1 ,march #ajth1 #ahab4 ,sir1--,this day ,i shall attend the account at ,wheal ,prosper ,mine1 in ,gwythian1 to contract with the adventurers for erecting a steam-engine on my improved plan1 for drawing the water #ej fathoms under the adit4 ,i called on ,wheal ,liberty adventurers at ,st4 ,agnes last week1 and found that several of them had given up their shares rather than put in a new engine1 and the remainder of them very sick4 ,i told them that ,i would fork the water with the present engine1 and draw instead of #dj gallons each stroke1 #dg fathoms deep 7which she did71 #he gallons per stroke1 #fe fathoms deep1 by altering the engine on the same principle as ,i have done with the ,dolcoath great engine1 and several more that are now altering4 ,the expense of altering the engine1 and forking the water to bottom1 and proving the mine1 will not exceed #ajjjl4 ,all the adventurers are very anxious to again resume their shares and make the trial1 on condition that ,i will undertake the completion of the job at a certain sum1 but not otherwise4 ,i am certain1 from what ,dolcoath engine is doing1 that ,i can far exceed the power above stated1 and perform the duty with one-half the coal the engine consumed before1 and would not hesitate a moment to engage the job on the terms they propose1 but ,i have not money sufficient to carry it into execution1 as ,i must lay out a large sum in erecting the engine on the ,gwythian ,mine1 and unless ,i can be assisted with #ejjl41 shall not be able to undertake the job4 ,if you think it worth your notice to encourage this undertaking by lending me the above sum for six months1 ,i will pay you interest for it1 and before drawing any part of it from you would get materials in the mine that should amount to above that sum1 and also give you an order on the adventurers to repay you the whole sum before receiving any part myself4 ,as ,i have been a bankrupt1 perhaps you may scruple on that account1 but that business is finally settled1 and ,i have my certificate2 and indeed ,i never was in debt to any person2 not one shilling of debt was proved against me under the commission1 nothing more than the private debts of my swindling partner4 ,at ,wendron we are working an engine lately erected on a copper lode1 which has a very promising appearance1 and near this spot you have land at ,besperson1 where there is also a very kindly copper lode1 which deserves trial2 if you are inclined to grant a sett1 ,i think ,i can find adventurers to join me to try the mine4 ,i have lately read a letter from your hind1 that the engine continues to mend2 it far exceeds my expectation4 ,i am now building a portable steam-whim1 on the same plan1 to go itself from shaft to shaft2 the whole weight will be about #cj cwt41 and the power equal to twenty-six horses in twenty-four hours4 ,the only difference in this engine and yours will be the fire in the boiler1 and without mason-work1 on account of making it portable4 ,i shall pass the rope from the fly-wheel round the cage of the horse-whim4 ,if you should fall in with any ,west ,india planter that stands in want of an engine1 he may see this one at work in a month1 which will prove to him the advantage of a portable engine1 to travel from one plantation to another4 ,the price1 completely finished and set to work1 free of all expense1 in ,london1 #ajel4 ,i am1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,n4,b4--,captain ,john ,stephens informed me1 a few days since1 that the lead mine at ,newlyn was rich4 ,in ,wheal ,prosper ,mine the first high-pressure expansive steam-condensing pole-engine had been worked1 just before the date of the foregoing letter1 and that evidence of increased power and economy was immediately followed by the application of the same principles of high-pressure steam and very expansive working to the ,watt low-pressure steam vacuum engines at ,wheal ,alfred1 ,dolcoath1 and other mines1 with such satisfactory results as to warrant his offering1 on the battle-ground of his first attack on the ,watt low-pressure steam vacuum principle at ,seal-hole in ,st4 ,agnes1 fourteen years before1#hg at his own pecuniary risk1 to so apply those principles in the ,wheal ,liberty low-pressure steam-engine1 which had failed to drain the mine1 lifting only at the rate of #ahhj gallons of water one fathom high at each stroke2 that it should lift an increased quantity of water1 and that1 too1 from an increased depth1 making the load equal to #eebe gallons1 and to perform such increase of work with one-half of the quantity of coal before used2 in other words1 he was willing to engage to make the old low-pressure steam-engine perform by its conversion into a high-pressure steam-engine threefold its original work1 and also to increase its duty or economic value sixfold2 resting his argument on the similar changes1 then to be seen in operation at ,wheal ,alfred ,mine1 and especially in the ,watt #fc-;inch double-acting engine at ,dolcoath1 whose history we have been tracing4 ,well might ,sir ,charles ,hawkins hesitate to believe what the experience of sixty years has barely sufficed to make plain to us4 ,footnote #hg3 ,see vol4 i41 p4 #ij4 ,,captn4 ,,trevithick1 ,,penzance1 ,march #bgth1 #ahac4 ,sir1--,in consequence of the conversation that has passed between you and ,west ,wheal ,tin ,croft adventurers1 the said adventurers have resolved to put an engine on that mine1 agreeable to the proposals offered by you2 that is1 the engine shall be capable of lifting a #e-;inch bucket1 #ej fathoms1 #d-;feet stroke1 #ae strokes per minute1 or a duty equal thereto2 for which they will pay you #ej guineas one month after the engine shall be at work1 and #ej guineas more at four months after that1 and #ej guineas more at four months from that time1 making the full payment of #aej guineas in nine months from the time the engine shall set at work1 the adventurers paying all expense1 except the engine materials1 which shall be delivered on the mine4 ,but in case the engine not performing the above duty1 the adventurers to be at liberty to return the same engine1 and you to pay back all the money that you had received for the said engine4 ,signed by ,,gabl4 ,,blewett1 in behalf of the ,adventurers and ,company4 ,trevithick was willing to spend more than his last penny in establishing the superiority of his high-pressure steam expansive engines1 but the selfishness of adventurers retarded their progress4 ,the atmospheric1 mentioned by ,watt as working in ,dolcoath in #aggg1hh did five or six millions of duty1 yet in ,trevithick's hands1 about #agih to #ahjj1 when he erected his globular boiler with internal tube1 one of them was tested with the #fc-;inch ,watt low-pressure vacuum engine1 when the latter did sixteen millions to ten millions by the atmospheric engine1 being nearly double the duty it performed in its original form2 and we shall still trace this same engine as ,bonze or ,gons until it increased to six times its first duty under the name of ,stray ,park #fc-;inch4 ,footnote #hh3 ,see vol4 i41 pp4 #cj1 #eg2 vol4 ii41 p4 #aae4 ,trevithick having erected a high-pressure steam condensing whim-engine at ,cook's ,kitchen1#hi and in ,dolcoath#ij a high-pressure puffer whim-engine1 pleaded hard in #ahjfia to be allowed to supply the large pumping engines of ,newcomen and ,watt with higher pressure steam from his cylindrical boiler1 which after years of consideration ,dolcoath1 in #ahaa1 agreed to4 ,in #ahac he wrote3--,that new engine you saw near the sea-side with me is now lifting forty millions1 one foot high1 with one bushel of coal1 which is very nearly double the duty that is done by any other engine in the county4 ,a few days since ,i altered a #fd-;inch cylinder engine at ,wheal ,alfred to the same plan1 and ,i think she will do equally as much duty4 ,i have a notice to attend a mine meeting to erect a new engine1 equal in power to a #fc-;inch cylinder single4#ib ,footnote #hi3 ,see vol4 i41 p4 #ia4 ,footnote #ij3 ,see vol4 i41 p4 #ia4 ,footnote #ia3 ,see vol4 ii41 p4 #adb4 ,footnote #ib3 ,see ,trevithick's letter1 ,january #bfth1 #ahac1 vol4 ii41 p4 #ee4 ,the beneficial results of those acts are too large to be here entered into in detail4 ,in round numbers1 the early pumping engines of ,newcomen did five millions2#ic ,trevithick caused them to do ten millions of duty with a bushel of coal4 ,watt1 during thirty years of improvements1 caused the duty to reach sixteen or twenty millions in #ahjj4 ,trevithick1 on the expiry of the ,watt patent1 then came into play1 and before he had reigned half the time of ,watt1 again doubled the duty of the steam-engine1 as he states in #ahac his new engine was doing forty millions1 being nearly double the duty of any other engine in the county4 ,these statements by ,trevithick agree very nearly with the generally-received accounts of the progressive duty of the large pumping steam-engine4 ,footnote #ic3 ,see vol4 i41 p4 #da4 ,in #agih ,davies ,gilbert1 ,esq41 and the late ,captain ,jenkin of ,treworgie1 found the average of the ,boulton and ,watt engines in ,cornwall to be about seventeen millions4 ,in ,august1 #ahaa1 the eight engines reported averaged #aeg millions4 ,during the year #ahad ,dolcoath great engine1 with a cylinder of #fc inches in diameter1 did twenty-one and a half millions nearly4 ,dolcoath ,shammal engine1 with a cylinder of #de inches in diameter1 did twenty-six and three-quarter millions4 ,dolcoath ,stray ,park engine1 with a cylinder of #fc inches in diameter1 did thirty-two millions4 ,in #ahae a trial was made1 to prove the correctness of the monthly reports4 ,stray ,park engine at ,dolcoath was chosen for the purpose1 because its reported duty was such as led some persons to entertain doubts of its accuracy4 ,the trial was continued for ten days1 to the full satisfaction of all concerned4 ,in #ahaf1 ,jeffrie and ,gribble erected a new engine1 #gf-;inch cylinder1 single1 at ,dolcoath1 which did forty millions4 ,this was the first instance of such duty having been performed by an engine of that simple construction4 ,in #ahai1 ,dolcoath engine performed the best during this year1 and at one time reached forty-eight millions4 ,in #ahbj1 ,treskerby engine1 to which ,trevithick's high-pressure pole had been adapted1 reached #djc millions4 ,in #ahaf1 ,sims also erected an engine at ,wheal ,chance1 to which he applied the pole adopted by ,trevithick in his high-pressure engines4 ,this engine attained to forty-five millions4 ,in #ahbh public attention had now been attracted to the improvements which ,captain ,grose had introduced into his engine at ,wheal ,towan4 ,the duty of this engine1 in the month of ,april this year1 equalled eighty-seven millions4 ,this again gave rise to suspicions of error in the returns4 ,this engine was accordingly subjected to a trial 7as ,stray ,park engine had been in #ahae71 which was superintended and conducted by many of the principal mine agents1 engineers1 and pitmen of other mines4 ,the quantity of coal consumed in #ahce1 compared with the quantity that would have been consumed by the same engines in the same time1 had they remained unimproved from the year #ahad1 shows that the saving to the county amounts to #ajj1jjj tons of coal1 or #hj1jjjl4 sterling per annum4#id ,footnote #id3 ,lean's ',steam-,engine in ,cornwall4' ,lean seems to have calculated on a bushel of coal as #id lbs4 ,in #agih1 when ,trevithick was about to give increased pressure of steam to the ,cornish engines1 his friend ,davies ,gilbert reported the average duty of the ,watt engine in ,cornwall to be seventeen millions4 ,in ,august1 #ahaa1 the reported duty averaged #aeg millions4 ,this was the month and year in which ,trevithick1 after twelve years of working evidences of the reasonableness of his promises of increased power and economy from using high-pressure steam1 was allowed to erect his cylindrical boilers for the large pumping engines in ,dolcoath ,mine4 ,has the reader realized that the #de-;inch atmospheric ,carloose engine1 of nearly #ajj years before1#ie had in #aggeif become the ,bullan ,garden engine of ,trevithick1 sen41 which was improved and re-erected by ,trevithick1 jun41 in #agii1ig when the name was again changed1 this time to ,shammal1 because it was linked to another engine1 no other than the ,watt #fc-;inch double engine8 ,this ,shammal #de-;inch took steam from the globular boiler1 using a pole air-pump#ih and a ,watt condenser1 though retaining the beam with the arched head and chain connection2 and again in #ahaa took still more highly expansive steam from the cylindrical boilers with a new beam and parallel motion1 enabling it in #ahad to beat its rival1 the ,watt ,dolcoath great double engine4#ii ,the old #fc-;inch ,gons1 under the name of ,dolcoath ,stray ,park engine1 with ,trevithick's improvements1 did sixty-seven per cent4 more work than the ,watt #fc-;inch with an equal quantity of coal4 ,footnote #ie3 ,see vol4 i41 p4 #ba4 ,footnote #if3 ,see vol4 i41 p4 #be4 ,footnote #ig3 ,see vol4 ii41 p4 #abj4 ,footnote #ih3 ,see vol4 ii41 p4 #abb4 ,footnote #ii3 ,see ,lean's report1 vol4 ii41 p4 #age4 ,this startling fact was disbelieved by the advocates of low-pressure steam1 and as the visible change in the ,dolcoath engine from ,newcomen to ,watt1 and from ,watt to ,trevithick1 had been gradual and not very striking1 and the public were careless of principles1 the one most puffed was most thought of2 but the money saved was tangible1 and in #ahae a special trial was made1 which lasted two days1 to discover if it was really true that ,trevithick's appliances could so increase the duty of the engine4 ,the #fc-;inch cylinder1 then called ,stray ,park engine1 was selected2 the result proved that the large saving reported from ,trevithick's boilers and expansive working during the last three or four years1 was an incontrovertible fact4 ,the high-pressure steam was also given to the defeated ,watt #fc-;inch double engine2 yet this newest of the three engines was the first to be condemned1 and her place was taken in #ahaf by an engine of #gf inches in diameter1 which ,trevithick promised should1 with his high steam and new expansive gear1 do the work of the ,watt #fc-;inch and the old #de-;inch put together2 which was more than fulfilled by its doing forty millions1 and1 as ,lean says1 was the first instance of such duty having been performed by an engine of that simple construction4 ,in #ahai the new #gf-;inch engine which had been erected by the mine engineers1 ,jeffrie#ajj and ,gribble1 who had long been employed by ,trevithick in ,dolcoath1 was the best in the county1 doing forty-eight millions1 nearly three times the duty as given by ,mr4 ,gilbert for the ,watt engine in #agih4 ,in #ahbg ,trevithick's pupil1 ,captain ,samuel ,grose1 erected his ,wheal ,towan engine1 which performed a duty of eighty-seven millions1 some of the working drawings of which were made by the writer4 ,in #ahce the principle laid down by ,trevithick had become so general in the county as to cause a saving to the ,cornish mines1 in coal alone1 of #hj1jjjl4 yearly4 ,in addition to this1 the increased power of the engine lessened the first cost by at least one-half4 ,footnote #ajj3 ,see vol4 i41 p4 #ajf4 ,the national importance of such weighty facts calls for further corroborative proof1 for we can scarcely believe that two atmospheric low-pressure steam-engines1 made before the time of ,watt1 could be altered so as to perform more work1 and at a less cost than the ,watt engine1 by an ingenious supply of higher steam pressure from ,trevithick's boilers1 together with the ,watt air-pump and condenser4 ,the following words from ,watt are descriptive of his practice1 though contrary to his patent claim3-- ,at a very early period1 while experimenting at ,kinneil1 he had formed the idea of working steam expansively1 and altered his model from time to time with that object4 ,boulton had taken up and continued the experiments at ,soho1 believing the principle to be sound1 and that great economy would attend its adoption4 ,the early engines were accordingly made so that the steam might be cut off before the piston had made its full stroke1 and expand within the cylinder1 the heat outside it being maintained by the expedient of the steam-case4 ,but it was shortly found that this method of working was beyond the capacity of the average enginemen of that day1 and it was consequently given up for a time4 ',we used to send out1' said ,watt to ,robert ,hart1 'a cylinder of double the size wanted1 and cut off the steam at half-stroke4' ,this was a great saving of steam1 so long as the valves remained as at first2 but when our men left her to the charge of the person who was to keep her1 he began to make1 or try to make1 improvements1 often by giving more steam4 ,the engine did more work while the steam lasted1 but the boiler could not keep up the demand4 ,then complaints came of want of steam1 and we had to send a man down to see what was wrong4 ,this was so expensive1 that we resolved to give up the expansion of the steam until we could get men that could work it1 as a few tons of coal per year was less expensive than having the work stopped4 ,in some of the mines a few hours' stoppage was a serious matter1 as it would cost the proprietor as much as #gjl4 per hour4#aja ,footnote #aja3 ,smiles' ',lives of ,boulton and ,watt1' p4 #bbh4 ,pole expresses the same view1 intimating that ,watt only used steam of #a or #b lbs4 pressure to the inch4 ,in ,watt's engine1 as is well known1 the pressure of steam in the boiler very little exceeded the pressure of the atmosphere4 ,he recommended that when the engine was underloaded1 this excess should be equal to about #a inch of mercury2 and when full loaded1 ought not to exceed #b inches2 adding1 ',it is never advisable to work with a strong steam when it can be avoided1 as it increases the leakages of the boiler and joints of the steam-case1 and answers no good end4'#ajb ,footnote #ajb3 ,appendix ,a to ,tredgold1 ',pole on ,cornish ,engines1' p4 #di4 ,mr4 ,watt's engines with such boilers 7which will not retain steam of more than #c-a_/f lbs4 per square inch above the atmosphere7 cannot be made to exert a competent power to drain deep mines1 unless the supply of steam to the cylinder is continued until the piston has run through more than half its course4#ajc ,footnote #ajc3 ',phil4 ,mag4 and ,annals1' ,n4,s41 vol4 viii41 p4 #cji1 by ,w4 ,j4 ,henwood4 ,in #ahja-b ,captain ,trevithick erected a high-pressure engine of small size at ,marazion1 which was worked by steam of at least #cj lbs4 on the square inch above atmospheric pressure4 ,in #ahjd1 as ,mr4 ,farey admits1#ajd the same gentleman introduced his celebrated and valuable wrought-iron cylindrical boilers1#aje now universally used in this county4 ,footnote #ajd3 ,ibid41 p4 #cac4 ,footnote #aje3 ,ibid41 vol4 i41 p4 #abg4 ,to these1 everyone at all acquainted with the ,cornish improvements ascribes a great part of the saving we have obtained4 ,this will farther appear from an extract from a valuable work edited by ,john ,taylor1 ,esq41 ,f4,r4,s4#ajf ,footnote #ajf3 ',records of ,mining1' p4 #afc4 ,the monthly consumption of coal in ,dolcoath ,mine was1 in #ahaa1 #fiab bushels2 in #ahab1 #dgeb bushels4#ajg ,the alteration in the boilers was the introduction of ,captain ,trevithick's cylindrical boilers in the place of the common waggon boilers1 which had until then been there in use4 ,footnote #ajg3 ,alteration in the boilers that year4 ,mr4 ,woolf1 as ,mr4 ,farey states1 came to reside in ,cornwall about the year #ahac1 and his 'first engines for pumping water from mines were set up by him in #ahad4'ajh ,footnote #ajh3 ',phil4 ,mag4 and ,annals1' vol4 x41 p4 #ig1 ,notes on ,some ,recent ,improvements of the ,steam-,engine in ,cornwall1 by ,w4 ,jory ,henwood1 ,f4,g4,s4 ,the foregoing was read at the ,philosophical ,society in #ahca1 to refute erroneous statements on the ,watt and ,trevithick engines4 ,my friend ,mr4 ,henwood had at that time made official experiments in conjunction with ,mr4 ,john ,rennie on the detail1 working1 and duty of high-pressure steam ,cornish engines1 the ,watt low-pressure steam principle having been wholly given up4 ,rees's ',cyclopdia'#aji also bears the following similar testimony to date of the increased duty3-- ,footnote #aji3 ,see ,rees ',on the ,steam-,engine1' published #ahai4 ,trevithick's high-pressure engine was erected in ,wales in #ahjd to ascertain its powers to raise water4 ,the duty was seventeen millions and a half pounds raised one foot high for each bushel of coals4 ,the high-pressure steam-engines require a greater quantity of coals1 in proportion to the force exerted1 than the engine of ,mr4 ,watt1 and consequently are not worked with advantage in a situation where coals are dear4 ,from the reports of the engines now working in the mines of ,cornwall1 which1 with the exception of a few of ,woolf's engines1 are all on ,mr4 ,watt's principle1 and most of them constructed by ,messrs4 ,boulton and ,watt1 taking the average of nine engines--bad1 good1 and indifferent together--they were found in ,august1 #ahaa1 to raise only thirteen millions and a half4 ,but when it was known by the engine keepers that their engines were under examination1 they took so much pains to improve the effects1 that by gradual increase the engines in #ahae lifted twenty-one millions and a half1 taking the average of thirty-three engines4 ,in #ahaf1 ,stray ,park1 a #fc-;inch cylinder1 #g feet #i inches stroke1 single-acting1 being one of the three engines on the vast ,dolcoath ,mine2 its performance in four different months was thirty-one1 thirty-one and a quarter1 twenty-eight1 and twenty-eight and a half millions4 ,this statement reveals a source of error in estimating the relative values of the ,watt and the ,trevithick engine2 that of the latter was the ,welsh locomotive1 compared in duty with the large ,watt pumping engine1 pointed out in ,trevithick's letter#aaj of that time1 as an unfair comparison2 the small high-pressure puffer1 in #ahjd1 is admitted to have done seventeen and a half millions of duty with a bushel of coal of #hd lbs41 while in ,rees' calculation of the engines1 he gives ,watt #id lbs4 of coal to a bushel2 and having stated that the ,watt pumping engines in ,cornwall1 in #ahaa1 averaged but thirteen and a half millions of duty1 draws the false conclusion that the high-pressure cannot compete with the low-pressure where coals are dear2 yet he agrees with other writers that the great increase in the duty of the ,cornish pumping engines commenced from #ahaa 7when ,trevithick first gave them his high-pressure steam72 and states that in #ahaf the ,stray ,park #fc-;inch cylinder single-acting engine1#aaa being one of three then working in ,dolcoath1 did thirty-one millions4 ,footnote #aaj3 ,see vol4 i41 p4 #aff4 ,footnote #aaa3 ,see ,watt's statement1 vol4 ii41 p4 #aae4 ,the ',encyclopdia ,britannica' on the question of duty states3#aab-- ,footnote #aab3 ,see ,steam-,engine1 published #ahfj4 ,the duty of the best of ,smeaton's engines was1 in #aggb1 #i1dej1jjj foot pounds per cwt4 of coal4 ,on the expiration of ,watt's patent1 about the year #ahjj1 the highest duty of his engines amounted to twenty millions1 or more than double the former duty1 which may represent the economical value of the improvement effected by ,watt under his various patents4 ,the reported duty of ,cornish pumping engines1 by the consumption of #id lbs4 of coals1 rose from an average of nineteen millions and a half1 and a maximum of twenty-six millions in #ahac1 to an average of sixty millions and a maximum of ninety-six millions in #ahdc4 ,it is necessary to bear in mind the distinction between the duty of a bushel of coal and #aab lbs4 ,here1 also1 are the same general facts as to the duty of the ,watt engine1 and the marked and rapid increase of duty dating from ,trevithick's ,dolcoath engines in #ahaa2 but the confusion and even contradictions in the statements prove how little the subject was understood4 ,a rough draft1 prepared by ,mr4 ,edmonds on ,trevithick's return from ,america1 dated #ahbh1 for an application to ,parliament for remuneration to ,trevithick1 says1 ',that this kingdom is indebted to your petitioner for some of the most important improvements that have been made in the steam-engine4 ',that the duty performed by ,messrs4 ,boulton and ,watt's improved steam-engines in #agih1 as appears by a statement made by ,davies ,gilbert1 ,esq41 and other gentlemen associated for that purpose1 averaged only fourteen millions and a half 7pounds of water lifted #a foot high by #a bushel of coal71 although a chosen engine of theirs under the most favourable circumstances lifted twenty-seven millions1 which was the greatest duty ever performed till your petitioner's improvements were adopted1 since which the greatest duty ever performed has been sixty-seven millions1 being much more than double the former duty4 ,that1 prior to the invention of your petitioner's boiler1 the most striking defect observable in every steam-engine was in the form of the boiler1 which in shape resembled a tilted waggon1 the fire being applied under it1 and the whole being surrounded with mason work4 ,that such shaped boilers were incapable of supporting steam of a high pressure or temperature1 and did not admit so much of the water to the action of the fire as your petitioner's boiler does1 and were also in other respects attended with many disadvantages4 ,that your petitioner's invention consists principally in introducing the fire into the midst of the boiler1 and in making the boiler of a cylindrical form1 which is the form best adapted for sustaining the pressure of high steam4 ',that the following very important advantages are derived from this your petitioner's invention4 ,this boiler does not require half of the materials1 nor does it occupy half the space required for any other boiler4 ,no mason work is necessary to encircle the boiler49999' ',that1 had it not been for this your petitioner's invention1 those late vast improvements which have been made in the use of steam could not have taken place1 inasmuch as none of the old boilers could have withstood a pressure of above #f lbs4 to the inch beyond the atmosphere1 much less a pressure of #fj lbs4 to the inch1 and is capable of standing a pressure of above #aej lbs4 to the inch4' ,trevithick's retrospect views of #ahbh are supported by the letter of the late ,michael ,williams1 ,m4,p41 the most experienced of ,cornish mine workers1 but belonging to the eastern district that had been for many years the users of the ,watt engines in ,cornwall4 ,in reference to his great improvements in the steam-engine1 ,i have a more particular recollection1 and can confidently affirm that he was the first to introduce the high-pressure principle of working1 thus establishing a way to the present high state of efficiency of the steam-engine1 and forming a new era in the history of steam power4 ,to the use of high-pressure steam1 in conjunction with the cylindrical boilers1 also invented by ,mr4 ,trevithick1 ,i have no hesitation in saying that the greatly-increased duty of our ,cornish pumping engines1 since the time of ,watt1 is mainly owing2 and when it is recollected that the working power now attained amounts to double or treble that of the old ,boulton and ,watt engine1 it will be at once seen that it is impossible to overestimate the benefit conferred1 either directly or indirectly1 by the late ,mr4 ,trevithick on the mines of this county4 ,i have often expressed my opinion that he was at the same time the greatest and the worst-used man in the county4#aac ,footnote #aac3 ,see letter of ,michael ,williams1 chap4 xix4 ,the late ,sir ,john ,rennie and other scientific persons were1 about #ahcj1 associated with ,mr4 ,henwood#aad in examining the work performed by ,cornish pumping engines3 their reports are curtailed in the following comments on ,wheal ,towan engine1 similar to ,trevithick's ,dolcoath engine of #ahaf1 except perhaps that the last named was a little inferior in its detail movements1 while much less care was taken to avoid unnecessary loss of heat4 ,footnote #aad3 ,henwood1 ',edinburgh ,journal of ,science1' #aj4 ,illustration3 ,,steam ,,diagram ,,of ,,wheal ,,towan ,,pumping ,,engine1 ,,erected #ahbg4 ,mr4 ,henwood also gave indicator diagrams of the expansion of the steam1 on one of which the writer has marked ten horizontal lines1 indicating the position of the piston at each foot of its stroke1 and ten longitudinal lines dividing the diameter of the cylinder into tenths4 ,the steam pressure in the boiler was #dfh lbs4 on the square inch above the atmosphere1 or #dfh lbs4 for each of the ten longitudinal line divisions4 x to c represents the top of the steam-cylinder #hj inches1 diameter2 x to ,f the length of the cylinder for a #aj-;feet stroke of the piston4 ,by the time the piston had moved through one-twentieth of its course1 reaching c1 the expansive working had commenced2 and when one-tenth of the stroke had been run1 half of a division was cut off1 showing by the curved indicator line the decrease in pressure of steam to #dd4df lbs4 ,the comparatively small passage through the steam-valve not giving room for sufficient steam to follow up the increasing speed of the piston1 led to its continued expansion in the cylinder1 and by the time the piston had moved #b feet1 reaching ,d1 the steam pressure was reduced by two divisions or #i4cf lbs41 or a pressure of #cg4dd lbs4 on the piston2 at this point the steam-valve was closed1 and the remaining four-fifths of the stroke was performed by expansion2 at the fifth horizontal line1 or middle of the stroke1 only three divisions of steam are left1 giving a pressure of #ad4jd lbs4 to the inch2 at the finish of the stroke there is only half a division1 from ,e to ,f1 or #b4cd lbs4 of steam to the inch above the pressure of the atmosphere4 ,on the return up-stroke of the piston1 when it had reached within a foot of the finish of its course at ,c1 the equilibrium valve closed1 causing the enclosed steam of #b4cd lbs4 to the inch to be compressed at the finish of the up-stroke shown by the curve ,g ,a to #i4cf lbs4 on the inch1 equal to its pressure about the middle of the down-stroke at ,n4 ,trevithick's expansive engine therefore1 commencing its work with steam of #df4h lbs4 on the inch above the atmosphere1 only took a full supply from the boiler during one-tenth of its stroke1 and none after one-fifth had been performed1 while at the finish of the stroke it had about the same pressure as ,watt began with4 ,the power of the ,watt low-pressure steam vacuum pumping engine was increased by ,trevithick from two to three fold1 and its economical duty in about the same proportion2 in other words1 he increased the effective power of the steam-engine two or three fold without additional consumption of coal4 ,in the ,wheal ,towan engine the steam-cylinder was #hj inches in diameter1 with a #aj-;feet stroke4 ,the shaft was #ijj feet in depth2 the main pumps #af inches in diameter2 the pump-rods were of wood1 about #ad inches square1 and weighed more than the column of water in the pipes4 ,the boilers were ,trevithick's cylindrical with internal tube1 wholly of wrought iron4 ,the cylinder and steam-pipes were surrounded with sawdust about #bj inches in thickness1 as a non-conductor of heat4 ,the upper surfaces of the boilers were covered with a layer of ashes for the same purpose4 ,the duty performed was #hfeh millions of pounds of water1 raised one foot high by the consumption of a bushel of coal weighing #hd lbs4 ,the immense power and economy of this engine are best understood by its average labour costing only one farthing in coal for lifting #ajjj tons one foot high4 ,at or about that time an old intimate of ,trevithick's1 ,captain ,nicholas ,vivian1 managed the mine1 and ,mr4 ,neville1 a shareholder1 also a user of steam-engines in ,wales1 observing the economical working of ,wheal ,towan high-pressure steam expansive engine1 doing eighty-seven millions1 requested its manager to examine colliery engines1 all of which were of the low-pressure kind2 one of them was a ,newcomen atmospheric1 whose duty was six millions2 four or five others were ,watt low-pressure steam vacuum engines1 doing fourteen millions2 therefore the high-pressure steam-engine did six times as much work with a bucket of coal as the low-pressure steam vacuum1 and fourteen times as much as the low-pressure steam atmospheric engine4 ,several competitive trials by the county engineers were published about that time1 in one of which1 after a personal examination of the engine1 ,mr4 ,w4 ,j4 ,henwood#aae and others reported a duty of #ibf millions with a #ia-lb4 bushel of coal4#aaf ,footnote #aae3 ,address1 ,royal ,institution of ,cornwall1 by ,w4 ,j4 ,henwood1 #ahga4 ,footnote #aaf3 ,trevithick calculated #hd lbs4 to a bushel2 ,watt generally #aab lbs42 ,lean #id lbs41 but latterly #aab lbs4 ,mr4 ,rennie had been a pupil1 a fellow-worker with low-pressure ,watt1 and while his son1 ,sir ,john ,rennie1 was examining the high-pressure steam expansive engine erected by ,trevithick's pupil1 ,captain ,samuel ,grose1 under the management of ,trevithick's friend1 ,captain ,nicholas ,vivian1 the latter was engaged in reporting on certain low-pressure steam-engines in ,wales1 one of which was a ,newcomen's atmospheric1 probably the last of its race1 whose principle of construction was a century old1 working in company with the ,watt low-pressure steam vacuum engine1 then half a century old1 the principles of both systems being on their last legs1 and under the care of ,trevithick's supporters4 ,during this jumble of engines1 old and new1 without a clear comprehension of their differences in principle1 ,trevithick1 who had just returned from ,america1 and lived within a few miles of ,wheal ,towan1 looked on unconsulted and unconcerned on questions which in his mind had been settled by him in ,dolcoath fifteen or twenty years before4 ,the writer1 during the ,wheal ,towan controversy1 was the daily companion of ,trevithick1 and made drawings of the engine at the works of ,harvey and ,co41 of ,hayle1 where it was constructed about #ahbg4 ,captain ,samuel ,grose's ,wheal ,towan engine was in general character similar to his teacher's ,dolcoath #gf-;inch engine of #ahaf1 working with about the same steam pressure and degree of expansion4 ,the valves1 gear1 and nozzles were perhaps improved in detail2 but the groundwork was unchanged4 ,the first high-pressure steam ,cornish pumping engine made in ,france was designed and superintended by the writer at the works of ,messrs4 ,perrier1 ,edwards1 and ,chaper1 at ,pompe--feu1 in ,chaillot1 a suburb of ,paris4 ,the principle was the same as the ,dolcoath engine1 and the detail differed but little from it or the ,wheal ,towan1 except that its exterior was a little more artistic than its prototypes in ,cornwall1 in keeping with ,french requirements4 ,it was built in #ahcf1 within a few yards of the low-pressure steam pumping engine erected by ,perrier and others in #aggi1 which still continued pumping water from the ,seine for the supply of ,paris4 ,stuart says1 ,an engine by ,boulton and ,watt was sent to ,france1 and erected by ,m4 ,perrier at ,chaillot1 near ,paris4 ,the ,french engineer1 ,proney1 with a detestable illiberality1 attributes all the merit of the improvements in the ,chaillot engine to his friend ,perrier1 the person who merely put together the pieces he had brought from ,soho4#aag ,footnote #aag3 ,stuart ',on the ,steam-,engine1' p4 #ada4 ,the ,perrier of #aggi was related to the ,perrier of the ,pompe--feu engine-building works of #ahcf1 and his nephew took the ,trevithick engine from ,paris to a coal mine not far from ,brussels1 but not fully understanding the use of the balance-bob--the woodwork for which had not been completed in ,paris1 though all other parts had been fully erected--did not find it easy to manage the engine4 ,the writer viewed ,perrier's move as an infringement of the agreement between him and ,edwards1 the partner of ,perrier and ,chaper1 and therefore declined to take any further interest in the engine4 ,mr4 ,edwards had before that been a partner with ,woolf1 in a small engineering works in ,lambeth2 and the writer had also before that been a pupil of ,woolf's1 in the works of ,messrs4 ,harvey and ,co41 of ,hayle4 ,the drawing of ',la ,belle ,machine' 7,plate ,,xiii471 of #ahcf1 serves not only as a record of that time1 but also in conjunction with the drawing of ,dolcoath engine of #ahaf1 enables an engineer to form a sufficiently correct idea of the ,wheal ,towan engine and boilers of #ahbg1 which in effective duty is scarcely excelled by the best pumping engines of the present day4 ,the events connected with those ,paris engines bring together the engineering works of ,watt1 ,proney1 ,perrier1 ,trevithick1 and ,woolf1 in the person of his once partner1 ,edwards4 ,the writer1 when constructing ',la ,belle ,machine1' had not the slightest knowledge of those links1 and heard the name and repute of his engine by the following chance3-- ,in #ahch a passenger leaving the train of the ,great ,western ,railway at ,drayton ,station1 asked the writer's permission to walk on the line and examine its construction4 ,during a short conversation he mentioned the having purchased at a sale in ,france the drawings of an engine known as ',la ,belle ,machine1' representing the ,cornish high-pressure expansive steam pumping engine3--a1 steam-cylinder1 #dh inches in diameter1 #h-;feet stroke2 b1 steam-pipe from boiler2 c1 regulating steam-valve1 double beat2 d1 regulating rod and handle for steam-valve2 e1 expansive steam-valve1 double beat2 f1 balanced lever and rod for opening expansive valve2 g1 expansive clamp on plug-rod1 with regulating rod and thumb-screws2 h1 cataract-rod for relieving expansive valve-catch2 i1 quadrant relieving the catch2 j1 plug-rod2 k1 equilibrium valve1 double beat2 l1 clamp in plug-rod to close equilibrium valve by its action on the handle2 m1 balanced lever and rod to open equilibrium valve2 n1 quadrant and catch relieving equilibrium valve by the action of cataract-rod2 o1 regulating slide on cataract-rod2 p1 equilibrium steam-pipe conveying steam from the top to the bottom of the piston2 q1 exhaust-valve1 double beat2 r1 clamp on plug-rod1 closing the exhaust-valve by its descent on the handle2 s1 balance lever and rod1 opening exhaust-valve2 t1 quadrant and catch1 relieving equilibrium valve by the action of cataract-rod2 u1 regulating slide on cataract-rod2 v1 exhaust-pipe to condenser2 w1 ,y-posts for carrying the gear4 ,the steam in the boiler was from #dj lbs4 to #ej lbs4 on the square inch above the atmosphere4 ,illustration3 ,,plate #ac4 ,,la ,,belle ,,machine4 ,,high ,,pressure ,,steam ,,expansion ,,pumping ,,engine4--#ahcf4 ,london3 ,e4 ,f ,n4 ,span4 #dh1 ,charing ,cross4 ,kell4 ,bros4 ,lith4 ,london4 ,lean states that had the pumping engines at work in ,cornwall in #ahce remained unimproved since #ahad1 at which time they had benefited by three years of continuous improvement1 a yearly additional expenditure of #hj1jjjl4 for coal would have been the consequence1 and that the first step was ,trevithick's expansive steam from the cylindrical tubular boiler1 engines using such steam performing a duty three or four fold what ,boulton and ,watt had ever attained1 or perhaps thought possible of attainment4#aah ,the birth of the idea of using expansive steam may in truth be traced back nearly one hundred years to the time of ,newcomen's atmospheric engine1 and the hope expressed in #agdf of a smaller boiler and more elastic steam#aai was partially realized in the engine and boiler of ,trevithick1 sen41 in ,bullan ,garden in #agge1 followed in #aghj by the competing engine erected by ,watt in ,dolcoath ,mine1 under ,trevithick's management4 ,little further change was made until #agii1 when the globular boiler and internal tube of ,trevithick1 jun41 gave a second start to the use in large engines of more expansive steam2 and even this partial move was the result of years of thought and practical experiment2 for in #agib1 when twenty-one years of age1 he was the elected judge on a competitive trial between the ,watt engine at ,seal-hole1 patented in #aghb1 and ,hornblower's double-cylinder engine at ,tin ,croft4 ,each engine performed a duty of ten millions1 both of them were called expansive1 while in fact neither of them were so1 for the pressure of the steam in the boiler did not admit of it4 ,as ,lean says1 ,as the steam used was raised but little above the pressure of the atmosphere1 it was found that the power gained did not compensate for the inconvenience of a more complicated and more expensive machine4 ,or1 as ,watt said to ,robert ,hart1 ,we resolved to give up the expansion of the steam until we could get men that could work it1 as he found it more costly than profitable4 ,again in #agih1 ,trevithick's own writing records his experiment in ,dolcoath between the ,bullan ,garden #de-;inch atmospheric engine and the ,watt #fc-;inch great double-acting engine1 when the latter did sixteen millions to ten millions by the atmospheric4 ,at that very time he was constructing his high-pressure steam portable engines1 and in the following year1 after seven years of most active experience1 prompted by the ,watt lawsuit against ,cornish engineers1 he in #agii gave the beaten #de-;inch engine steam of a higher pressure from the stronger globular boiler4 ,people1 following the ideas of ,watt1 were still afraid of ,trevithick's plans1 distinctly laid down in his letters of #ahjf1 recommending a cylindrical boiler for the ,dolcoath pumping engine1 because similar boilers giving steam to his whim-engines have enabled them to beat the ,watt whims4 ,this continued until #ahaj1 when the greatly-increased power and economy of the high-pressure expansive steam pumping engine at ,wheal ,prosper caused the neighbouring ,dolcoath in #ahaa to give ,trevithick's plans free scope4 ,the long smouldering rivalry between low and high pressure1 on the eve of the final discomfiture of the former1 burst forth in loud words and evil prognostications1 causing the mining interest of ,cornwall to appoint an examiner who should publish monthly the duty performed by the various pumping engines1 the first of which appeared in the autumn of #ahaa1 when ,trevithick was building his boilers in ,dolcoath1 and preparing the engines1 as far as was possible1 to submit to strong steam4 ,by expansive valves and suitable gear1 balance of power between the engine and the pump-work necessitating balance-bobs1 strengthening the pit-work to bear the more powerful and sudden movement1 and fifty other things1 which we know must have presented themselves in such work1 occupied the greater part of ,trevithick's time from #ahaa to #ahad4 ,that first report enumerates twelve pumping-engines1 probably all of them ,watt engines1 averaging a duty of seventeen millions4 ,footnote #aah3 ,see ,lean's ,historical ,statement1 p4 #aed2 published #ahci4 ,footnote #aai3 ,see vol4 i41 p4 #g4 ,we have before traced the rapid and immense increase in the power and in the duty of ,cornish pumping engines from #ahaa1 and it may be taken as comparatively true in the larger sense applying to the improvement of the steam-engine everywhere4 ,dolcoath ,mine1 one hundred years ago1 under the management of ,trevithick1 sen41 followed by his son as the strong-steam engineer1 and by his grandson as one of the committee of management in these modern times1 has served during that long period to illustrate the progress of the steam-engine1 and still in active operation1 was thus spoken of in ',the ,times' of ,dec4 #ahth1 #ahga3--,this old and extraordinary mine is now raising about #ajj tons of tin every month1 worth from #hjjjl4 to #ijjjl4 ,,chapter ,,xxi4 ,,engines ,,for ,,south ,,america4 ,rough draft4 ,,sir1 ,,camborne1 ,may #bjth1 #ahac4 ,yours of the #gth inst4 ,i should have answered by return1 as requested2 but an unexpected circumstance prevented my being at ,swansea as early as proposed1 which1 as it happens1 best suits your purpose as well as my own4 ,i shall not be able to be there within twenty days from this time1 of which ,i will give you timely notice4 ,i hope before that time ,mrs4 ,rastrick will be safe out of the straw4 ,i have been detained in consequence of a strange gentleman calling on me1 who arrived at ,falmouth about ten days since1 from ,lima1 in ,south ,america1 for the sole purpose of taking out steam-engines1 pumps1 and sundry other mining materials to the gold and silver mines of ,mexico and ,peru4 ,he was recommended to me to furnish him with mining utensils and mining information4 ,he was six months on his passage1 which did not agree with his health1 and has kept his bed ever since he came on shore2 but is now much recovered1 and hopes to be able to go down in the ,cornish mines with me in a few days4 ,i have already an order from him for six engines1 which is but a very small part of what he wants4 ,i am making drawings for you1 and intend to be with you as soon as they are finished4 ,money is very plentiful with him1 and if you will engage to finish a certain quantity of work by a given time1 you may have the money before you begin the job4 ,the ,west ,india engine will suit his purpose4 ,i shall have a great deal of business to do with you when we meet4 ,in the meantime please to forward the thrashing engines to ,cornwall as quickly as possible4 ,the engine for ,plymouth will be put to break the ground as soon as ,i can find time to go up there4 ,please to say when and by what ship ,i shall have the small engines4 ,i remain1 ,sir1 ,your very obedient servant1 ,r4 ,t4 ,to ,,mr4 ,,john ,u4 ,,rastrick1 ,bridgenorth1 ,shropshire4 ,the copper mine mentioned in my last is improving very fast4 ,the strange gentleman referred to was ,don ,francisco ,uville1 a person of great influence in ,lima1 who a year or two before had travelled from ,peru to ,england and back1 in search of steam-engines to pump water from the ancient gold and silver mines then flooded and idle4 ,boulton and ,watt1 at ,soho1 on being consulted1 discouraged the attempt1 because of the difficulty of conveying heavy machinery over mountain pathways1 and also because their low-pressure vacuum engine1 using steam but slightly above atmospheric pressure1 would be much less effective in the comparatively light atmosphere on the high summits of the ,cordillera ,mountains than in ,england4 ,uville1 who had heard of the wonderful ability of ,english engineers to construct steam pumping engines1 was utterly downhearted at this decision of the great ,soho engineers1 and while dejectedly wandering through the streets of ,london1 unconsciously gazed into the shop window of ,mr4 ,roland in ,fitzroy ,square1 near the spot on which ,trevithick had run his railway locomotive three years before4#abj ,rumour of passed events may have led him to visit the ground on which had worked a new kind of steam-engine4 ,his searching glance discovered among numerous articles for sale1 an unknown form that might be the talisman he had travelled thousands of miles in search of4 ,the shopkeeper informed him that it was a model of ,richard ,trevithick's high-pressure steam-engine1 which worked without condensing water1 or vacuum4 ,if what he heard was true1 why should it not work equally well in the light atmosphere of the mines8 ,the great engineer at ,soho might be in error or ignorance4 ,the experiment1 as a last resource1 was worth making4 ,he would pay the #bjl4 for the model1 carry it to the mines of ,cerro de ,pasco1 in the high mountains above ,lima1 where1 if it worked as well as it did in ,london1 the rich mines of ,peru would again reveal their long-hidden treasure4 ,the model was conveyed by ship to ,lima1 and then on a mule up the narrow precipitous ascents to ,cerro de ,pasco1 over mountains more than #bj1jjj feet high4 ,fire was placed in the small boiler as he had seen it done in ,london1 and with the same result1 to the great joy of ,uville1 who determined to revisit ,england in search of the inventor of this new and wonderful power4 ,on his return voyage1 when rounding ,cape ,horn1 bets were made on the chances of his finding the man who had invented the high-pressure steam-puffer engine1#aba and of his being able to persuade such a person to make the required engines and accompany them to ,peru4 ,such gloomy forebodings ended in an attack of brain fever4 ,the vessel touched at ,jamaica1 where ,uville was landed4 ,on recovering health and strength he embarked for ,england in one of the packet-ships1 and during the voyage still spoke of the object of his search4 ,a fellow-traveller1 called ,captain ,teague1 rejoiced him by saying1 ,i know all about it2 it is the easiest thing in the world4 ,the inventor of your high-pressure steam-engine is a cousin of mine1 living within a few miles of ,falmouth1 the port we are bound for4 ,on landing1 ,uville1 still weak and obliged to keep his bed1 was told that ,trevithick1 the engineer1 lived in ,london1 and was constructing the ,thames ,tunnel2 but further inquiry showed that he also had suffered from brain fever1 and had just returned to ,penponds1 only a few miles from ,falmouth4 ,on the #ajth of ,may1 #ahac1 a letter reached ,trevithick1 requesting him to visit the sick ,uville1 and in a fortnight from that time the engineer had mastered the requirements of the ,peruvian mines1 and had designed and made arrangements for the supply of six pumping engines1 together with the pumps and all things necessary for the underground workings2 the whole to be delivered in four months4 ,footnote #abj3 ,see vol4 i41 p4 #aid4 ,footnote #aba3 ,see ,london locomotive1 vol4 i41 p4 #aih4 ,rough draft4 ,,sir1 ,,camborne1 ,may #bbnd1 #ahac4 ,i have engaged to get six engines1 with pit-work1 c41 to send abroad4 ,a great part of the wrought-iron work and the boilers ,i have arranged for in ,cornwall4 ,these engines will be high-pressure engines1 because the place they are for has a very deep adit driven into the mountain2 and lifting condensing water to the surface would be a greater load than the whole of the work under the adit level4 ,i call a set of work1 a #bd-;inch cylinder single engine1 #f-;feet stroke1 piston1 cylinder bottom1 single nozzle1 with two #e-;inch valves and perpendicular pipe2 no cylinder top2 the piston-rod not to be turned2 #c-;inch safety-valve1 fire-door1 two small ,y9999symbol shafts and gear-handles1 c42 a good strong winch set in a broadish frame1 such as is often used on quays or in quarries1 #be fathoms of #ab-;inch pumps1 a #ab-;inch plunger1 an #aa-;inch working barrel1 clack-seat and wind-bore1 with brass boshes and clacks1 a force-pump for the boiler1 and #aj fathoms of #c-;inch pipes to carry the water to and from the engines4 ,i have engaged to supply six full sets of the above-mentioned materials4 ,all these castings must be delivered in ,cornwall in four months from the time the orders are given2 therefore1 if you take the job1 or any part of it1 you must enter into an engagement to fulfil it in the time4 ,as there ought not to be a moment lost1 ,i wish you to answer me immediately in what time you will deliver those materials in ,cornwall2 or otherways1 what part of them you can execute in the time4 ,i am making the drawing1 which will be ready before ,i can receive your answer4 ,for whatever part of the job you may engage ,i will lodge the money to pay for the whole in ,mr4 ,fox's hands1 which will then be paid for before you begin the work1 as soon as you execute the agreement4 ,r4 ,t4 ,,mr4 ,,pengilly1 ,neath ,abbey1 ,south ,wales4 ,it is an odd coincidence that while writing of the events of fifty-eight years ago1 pumping engines are being sent to those same mines with the steam-cylinder in twenty-two pieces1 no piece to weigh more than #cjj lbs4--a facility in mechanical arrangements not enjoyed by ,trevithick--having ,trevithick's high-pressure boilers1 giving steam of #ej lbs4 on the inch4#abb ,footnote #abb3 ,made by ,harvey and ,co41 ,hayle1 #ahgj4 ,rough draft4 ,,sir4 ,,camborne1 ,june #bnd1 #ahac4 ,i drop you this note just to inform you that ,i have begun your job4 ,yesterday ,i engaged a great many smiths and boiler-builders1 who set to work this morning4 ,i have also engaged all the boiler-plates in the county1 which will be sent to-day to the different workmen4 ,the master-smiths that ,i have engaged are the best in the kingdom4 ,i have obligated them to put the best quality of iron1 and to be delivered at ,falmouth within four months4 ,i have been obliged to give them a greater price than ,i expected1 otherwise they would not turn aside their usual business employment for a short job of four months4 ,mr4 ,teague is with me1 and one other1 assisting about the drawings4 ,if you call at ,camborne about ,friday1 shall be able to show you the designs4 ,the drawings for the castings will be sent to the iron-founders by the end of this week2 and by the end of next week shall have the whole of the different tradesmen in full employ4 ,if you wish to have a greater quantity of machinery ready by the end of ,september1 there ought to be as little time as possible lost in giving your orders4 ,i can get you double the quantity1 provided you give the orders in time4 ,as soon as it is convenient to you to arrange the payments ,i would thank you to inform me1 because we find in practice that the best way to make a labouring machine turn quickly on its centres1 is to keep them well oiled4 ,r4 ,t4 ,f4 ,,uville1 ,esq41 ,,mr4 ,,hooper',s1 ,falmouth4 ,n4,b4--,if you intend to be at ,camborne1 please to drop me a note by post1 and ,i will be at home4 ,in all ,trevithick's moves there was a scramble for money1 in which he invariably came worst off4 ,he could give a good hint that working centres would not turn well without the essential oil2 but he failed to apply the principle to himself4 ,liberal words and golden prospects carried him off at once2 and before ,uville was strong enough to visit the ,cornish mines and to fully explain what he wanted1 the machinery was being made1 though at that same time the thrashing and ploughing engines1 and the locomotive and rock-boring engine1 and the great fight with ,watt at ,dolcoath1 were in progress4 ,rough draft4 ,,mr4 ,,rastrick1 ,,camborne1 ,june #hth1 #ahac4 ,sir1--,enclosed ,i send to you a drawing for a set of pumps for one of the engines for ,south ,america1 with a drawing for a part of the castings for one of the boilers1 for you to make a beginning4 ,the drawings for the engines ,i will send in a few days4 ,the ,spanish gentleman who is now gone to ,london to arrange his money concerns1 will be down again in about ten or twelve days1 and then we shall both call at ,bridgenorth1 and bring with us the engagement for you to sign1 for the performance of such quantities of work as you can execute in four months4 ,i have made arrangements with the smiths and boiler-99builders here1 to weigh and pay at the end of every week4 ,the regulation of your payment is left to you to point out in any way you please4 ,as time is of the greatest consequence1 ,i hope you will set to work immediately4 ,the reason for making the pumps so short1 is on account of the extreme badness of the roads over the mountains1 where these engines are to be conveyed1 it being almost impossible to carry above five hundredweight in one piece4 ,the ,west ,india engine is sold to send to ,lima1 but not to be conveyed over the mountains4 ,i shall also bring drawings with me for one or two winding engines for the same place4 ,please write to me by return of post4 ,r4 ,t4 ,rough draft4 ,,camborne1 near ,,truro1 ,june #aath1 #ahac4 ,,mr4 ,,francis ,,uville1 at ,,messrs4 ,,campbell ,,and ,,co4',s1 ,london4 ,sir1--,i have your favour of the #ith instant1 respecting the weight of the largest parts of the engines4 ,i will take care to reduce the weight if possible1 so as to be carried on the backs of mules4 ,by the time ,i receive your letter ,i shall have arranged the whole of the engine business1 and intend to go immediately to ,wales and ,shropshire1 to get the engagements executed for the performance of the work by the time proposed4 ,i shall write to you again before ,i leave home1 and as soon as ,i arrive in ,wales will also write to you4 ,i shall not stay in ,wales above two days1 but go to ,bridgenorth in ,shropshire1 where ,i hope to have the pleasure of meeting you1 as it will only be about twelve hours' ride out of your road to ,cornwall4 ,in the ,north ,i shall introduce you to the sight of a great deal of mining and machinery1 and in about ten days from the time you arrive at ,bridgenorth1 shall be able to accomplish the business so as to return again to ,cornwall4 ,i would thank you to inform me as early as you can1 of the number of engines you intend to get executed by the proposed time1 because when ,i am in the ,north ,i shall be able to arrange with the founders accordingly4 ,the smiths are all at work for you4 ,r4 ,t4 ,rough draft4 ,,mr4 ,,uville1 ,,cornwall1 ,,camborne1 ,june #aith1 #ahac4 ,sir1--,your favour of the #ith instant1 dated from ,falmouth1 ,i received1 and in return wrote to you immediately--directed for you at ,messrs4 ,campbell and ,co4's1 ,london4 ,as you said in your last letter1 that immediately on your arrival in town you would write to me1 ,i have expected every post since last ,tuesday would have brought me a letter2 but as ,i have not received it according to your promise1 ,i am fearful that your letter may be unexpectedly detained1 especially as you told me the last time ,i saw you at ,falmouth1 that you would enclose me a bank post bill4 ,all the founders and other tradesmen are in full employ on your engines4 ,i intended to have left ,cornwall for ,wales and ,shropshire by this time1 with the founders' articles for execution2 but being disappointed in not hearing from you1 agreeable to our appointment1 ,i shall delay it until ,i hear from you1 which ,i must request you to have the goodness to do by return of post1 because those delays make very much against the execution of your work2 and as time is of so great a consequence to you1 ,i hope you will not lose a moment in writing and giving me the necessary instructions1 with a few drops of that essential oil that you proposed sending me on your arrival in town4 ,r4 ,t4 ,the sugar rolling-mill engine that had been made for the ,west ,indies so pleased ,uville that he purchased it at once1 intending it for the ,mint at ,lima4 ,he also ordered one or two winding engines1 in addition to the pumping engines4 ,trevithick had arranged that no piece should exceed #efj lbs4 in weight4 ,then came ,uville's order1 if possible to be reduced so as to be carried on the backs of mules4 ,since that time the path on the mountains has been improved1 yet the present limit of weight is #cjj lbs4 ,the absence of the promised bank post bill was another difficulty4 ,rough draft4 ,,camborne1 ,june #bcrd1 #ahac4 ,,mr4 ,,francis ,,uville1 at ,,messrs4 ,,campbell ,,and ,,co4',s1 ,park ,buildings1 ,london4 ,sir1--,your favour of the #aith instant came safe to hand4 ,i was in hopes that ,i should have found a remittance enclosed4 ,all the tradesmen that ,i have employed on your work were to have been paid every ,saturday1 and ,i made my arrangement with you accordingly4 ,unless this mode of proceeding is followed up1 you cannot get your work done in any reasonable time1 especially as you are an entire stranger4 ,for my own part ,i have placed the greatest confidence in your honour1 with which ,i am fully satisfied4 ,but ,i have to get this work from a great number of different tradesmen1 and must make regular payments agreeable with my engagements with them4 ,as the articles are about to be executed by different tradesmen1 regular weekly payments ought to be established1 of which ,i informed you before the work began4 ,i am ready for my journey to ,wales and ,shropshire1 but cannot proceed with further engagements until ,i hear again from you4 ,i have placed the fullest confidence in your word1 a proof of which you have in the great exertion ,i have made to get the work done2 but unless you in return place some confidence in me1 or any other engineer that you may employ1 a work of this magnitude cannot be carried on with promptitude4 ,as the whole of the work in my part has been put into immediate operation1 it would be a very serious loss both of money and time to discharge the hands4 ,i hope you will fully consider this business1 and must beg you will have the goodness to write to me by return of post4 ,on receiving the needful from you ,i shall leave ,cornwall for ,wales and ,shropshire4 ,r4 ,t4 ,trevithick for once in his life was wise1 and would not start on his journey to ,bridgenorth until the money had reached him4 ,this prudent resolve was soon forgotten in the love of making the steam-engine useful2 and as such creations in his hands grew into shape and size before other men would have got through preliminary discussions1 pecuniary difficulties sprang up1 as mushrooms do in a night4 ,rough draft4 ,,camborne1 ,september #dth1 #ahac4 ,,messrs4 ,,hazeldine1 ,,rastrick1 ,,and ,,co41 ,gentlemen1--,enclosed you have three of ,mr4 ,uville's drafts1 value one hundred and fifty pounds4 ,i should have sent it in one draft1 but had not a suitable stamp4 ,the castings1 pipes1 ale1 c41 arrived safely4 ,i hope that all the boilers and wrought-iron work will be finished by the end of this month1 and shipped off for ,london4 ,immediately after ,mr4 ,uville and ,i shall leave ,cornwall for ,bridgenorth on our journey to town4 ,we are both very anxious to see the ',sanspareil' engine at work1 and hope you will have it ready by that time4 ,i have received orders from different persons since ,i have been here1 for steam-engines for the ,west ,indies1 and must1 if possible1 have three ready early in ,november1 as the ships sail then that will take them4 ,i wish you would say in your next if this can be done in time1 because these persons are very extensive agents for the planters1 and are extremely anxious to generally adopt them in the ,west ,indies4 ,we find from your letter that you are getting on pretty fairly with ,uville's work4 ,i remain1 ,your very humble servant1 ,,richard ,,trevithick4 ,rough draft4 ,,gentlemen1 ,,camborne1 ,september #gth1 #ahac4 ,after writing to you on ,sunday last1 ,mr4 ,uville received letters from ,cadiz1 from the ,spanish ,government1 informing him that there was a line-of-battle ship there that should take the engines to ,lima4 ,now as this ship is detained for this purpose1 all possible dispatch must be made to get the whole of the materials shipped as early as possible for ,cadiz4 ,i am pushing the smiths as hard as possible1 and you must do the same at your works1 that the greatest dispatch may be made4 ,i am ordered by ,mr4 ,uville to request you to get one water-engine1 pumps1 c41 complete1 one winding engine1 winding apparatus1 c41 complete1 and one crushing apparatus1 complete1 in addition to the former order4 ,i wish you would also get on as fast as possible with the new engine1 but do not let this engine prevent the getting forward the work for ,lima4 ,i wish to have made apparatus to work expansively1 and also a temporary water-pump1 to load the engine1 so as to prove its duty by the consumption of coal4 ,if the jobs are not completed by our arrival1 you need not expect any rest until its completion4 ,your answer will oblige1 ,r4 ,t4 ,,messrs4 ,,hazeldine1 ,,rastrick1 ,,and ,,co4 ,the money difficulty was for a time surmounted1 with a prospect of the completion and shipment of the work for ,london within four months of the giving of the order2 and the ,spanish ,government proposed that a line-of-battle ship should take the engines to ,lima from ,cadiz4 ,an order was given for another pumping engine and another winding engine1 to be provided with gear for working expansively1 and a temporary water-pump1 that in case of need the amount of work the engines could do with a given amount of coal might be tested4 ,a crushing machine1 now called quartz-crusher1 also formed part of this additional order4 ,the new engine1 which he hoped they would get on with1 was probably the steam locomotive plough then being constructed at ,bridgenorth4 ,rough draft4 ,,gentlemen1 ,,camborne1 ,september #bbnd1 #ahac4 ,i have your favour of the #adth instant1 and hope to find you as forward on your job on our arrival at ,bridgenorth as you state4 ,i expect all the boiler and smith work will be shipped for ,london early in ,october2 we shall then leave ,cornwall for your works1 at which time you will be very much annoyed with our company1 unless we find your assertions grounded on facts4 ,enclosed ,i send you ,mr4 ,uville's draft for #aejl4 ,your receipt for the draft enclosed in my letter of the #afth instant has not yet arrived4 ,i hope you will also have all the apparatus ready to try the new engine2 ,mr4 ,uville is very anxious to take the first of these new engines with him4 ,when you send a receipt for the enclosed1 please to say what state of forwardness the whole of our work is in1 and do not neglect a moment to get the whole executed with all possible dispatch4 ,nothing short of a want of cast iron will confine our friend in ,england one day after the end of this month4 ,i am1 ,gentlemen1 ,your very humble servant1 ,,richard ,,trevithick4 ,,messrs4 ,,hazeldine1 ,,rastrick1 ,,and ,,co4 ,it seems probable that in #ahac a railway locomotive1 with apparatus for rock boring1 and steam-crane1 was made for ,south ,america as the forerunner of the ',sanspareil' of #ahbi4 ,rough draft4 ,,gentlemen1 ,,camborne1 ,october #ast1 #ahac4 ,i received your favour of the #bgth last evening1 and now enclose you another draft of ,mr4 ,uville's for #aejl4 ,we shall wait impatiently for your next letter to know when you will finish4 ,mind1 this is the #ast of ,october1 and agreeable to promise the time is up4 ,mr4 ,uville wishes you to cast sixty carriage-wheels for him1 #aa inches in diameter from out to out1 and to weigh about #bj lbs42 cast them of strong iron1 and of a strong pattern1 to take a #a-a_/b-;inch axle by #b-a_/b inches deep in the hole2 also cast four plunger-pistons #aa inches diameter to suit the #aa-;inch working barrels1 provided it should be used for the purpose of a plunger4 ,they must be in every respect the same as the #ad-;inch plunger-pistons1 only #c inches less in diameter4 ,illustration ,soon after the receipt of your next letter you may expect to see us1 as a vessel has been engaged to take all the boilers and smith work on board to-morrow week for ,london4 ,i remain1 ,sir1 ,your humble servant1 ,,richard ,,trevithick4 ,,messrs4 ,,hazeldine1 ,,rastrick1 ,,and ,,co4 ,probably those cast-iron wheels were ordered with a view to steam locomotion in the ,cordilleras4 ,an engine is described in the invoice as having chimney1 axles1 carriage-wheels1 c4 ,rough draft4 ,,gentlemen1 ,,camborne1 ,october #aath1 #ahac4 ,on making the drawings of the engine with the winding and crushing apparatus1 when at work ,i find that if there is no crank1 but the sweep rod is connected to a pin in the arm of the fly-wheel2 in that case the fly-wheel will cut off the engineer from getting at the cock2 but if the sweep is connected to a crank1 then there will be sufficient room4 ,the copy of materials taken from your books and given to ,mr4 ,uville does not say in which way it was intended4 ,i send you a sketch how it will stand worked by a pin in the fly-wheel1 and also if worked by a crank over the cylinder1 with the fly-wheel outside the wood partition of the house4 ,if you have cast all the parts for the winding engine1 you should try to alter it1 having the fly-wheel outside the wall of the house1 and a crank for the inside end of the shaft4 ,the fly-wheel shaft will be nearly the same length both ways1 only it must be long enough for the fly-wheel to pass between the wood partition and the #d-;feet cog-wheel4 ,the centre of the winding cylinder will be #ag inches from the outside of the wood end of the house1 against which the fly-wheel ought to run4 ,i have received your favour of the #eth instant1 and have enclosed1 agreeably to your request1 a draft of ,mr4 ,uville's for #hjjl41 which will be the last from ,cornwall4 ,all ,i have to say is1 you have taken longer time for the completion of your work than you first proposed1 which has made ,mr4 ,uville apprehensive that it will be the means of his losing the ,spanish ship promised him to take the engines4 ,he desires me to inform you that he has complied with this advance on purpose to enable you to push your work with the utmost exertion4 ,illustration3 ,,winding ,,engine ,,for ,,south ,,america4 ,please to inform us the precise time we must quit ,cornwall for ,bridgenorth2 we now wait entirely on you without any other thing to engage us4 ,i fear ,mr4 ,rastrick being so much from home will impede our job4 ,if we miss this ship it will certainly make much against us all1 losing three or four months in getting a ,south ,sea whaler1 and having the engine in a vessel not able to defend herself against an enemy1 and having to pay #ae or #bj per cent4 insurance1 and prevent our getting other orders for another set of engines1 and if taken by the enemy perhaps altogether damn the undertaking4 ,therefore ,i would have you to well consider the great inconveniences attending delay4 ,i think ,i need not say much more to you on this head1 as you ought to feel more for your own interest than ,i can scribble to you on paper4 ,yours1 c41 ,r4 ,,trevithick4 ,,messrs4 ,,hazeldine1 ,,rastrick1 ,,and ,,co4 ,this rough hand-sketch and letter fully describing his requirements1 is an illustration of the facility with which ,trevithick designed his engines and made known his wishes to others4 ,rough draft4 ,,gentlemen1 ,,camborne1 ,october #bcrd1 #ahac4 ,mr4 ,uville wishes everything to be sent off as soon as finished1 except the rolling engine1 which is to remain until he arrives4 ,we intend to leave ,cornwall for ,bridgenorth on ,monday1 ,november #ast4 ,you may expect to see us three days after that date4 ,the wheels ordered for the carriages are to run on the ground and not on railroads4 ,mr4 ,uville now wishes to have seventy-two instead of sixty as ordered before4 ,i remain1 ,gentlemen1 ,yours1 c41 ,r4 ,,trevithick4 ,,messrs4 ,,hazeldine ,,and ,,co4 ,the last-named engine was intended for the coinage operations in the ,mint at ,lima4 ,the use of railway locomotion had been under discussion with the engine builders1 and probably those particular carriage-wheels were ordered in the hope that the portable engine built for conveying itself from place to place in the sugar plantations of ,jamaica1 would in the ,cordilleras be made to draw waggons on common roads4 ,the hand sketch of the winding engine in the letter of the #aath ,october1 was to correct an error in an order hastily given a month before2 when1 to save time1 outline instructions for this complicated work were hurriedly sent to the manufacturer1 that a commencement might be made while the more perfect detail drawings were being completed2 the first-proposed position of the fly-wheel would prevent the engineman from conveniently reaching the four-way cock2 ,trevithick therefore suggested that the fly-wheel should be moved to the outside of the house1 and a crank placed on the end of the driving shaft in lieu of the crank-pin in an arm of the fly-wheel4 ,the sketch illustrating this change makes us fully acquainted with the kind of winding high-pressure steam-puffer engines of #h-;horse power1 with open-top cylinders of #ab inches in diameter and about #c feet #f inch stroke1 sent to ,peru in #ahad4 ,steam1 of #cj lbs4 to the inch above the pressure of the atmosphere1 was admitted under the bottom of the piston by a cock moved by an eccentric on the fly-wheel shaft2 the gradual closing of the cock reduced the supply of steam when about one-third of the stroke had been made1 wholly cutting it off some time before its completion1 making it a high-pressure steam expansive engine4 ,the movement of the cock then turned the steam from under the piston into the chimney blast-pipe1 and the down-stroke was performed by the weight of the descending piston1 made more than usually deep and heavy to prevent the tendency to twist in the cylinder from the angle of the jointed connecting rod1 and also by the momentum of the fly-wheel and its balance-weight1 moving at a speed of thirty strokes a minute4 ,its boiler was the ,trevithick wrought-iron cylindrical1 with internal tube and fire-place1 but so arranged that if necessary the fire could be placed in brick flues under the boiler1 returning through the tube4 ,the cylinder for the winding engine was probably fixed in the boiler1 costing1 with whim-barrel and winding apparatus complete and ready for work1 #bajl4 ,does the reader ask1 ,did so cheap an engine ever work8 ,or perhaps his knowledge of engineering gives rise to the question1 ,how did it work8 for it looks like a ,newcomen of just exactly a hundred years before1 only it needs no injection water or great main beam2 and certainly it is not a ,watt1 for it has neither air-pump nor condenser1 nor vacuum1 nor cylinder-cover1 nor parallel motion1 nor any other thing like ,watt invented2 but it has high-pressure steam1 which he disapproved of1 and it really worked thousands of miles away1 where there were no mechanics to keep it in order1 and on mountains so difficult of access1 and in so light an atmosphere1 that ,watt1 who had the first chance of supplying steam-engines to the ,new ,world1 declared it to be impossible4 ,the pumping engines are described in ,trevithick's note of #bbnd ,may4 ,they also were high-pressure puffer-engines with open-top cylinder1 #bd inches in diameter1 #f-;feet stroke1 with a cross-head working in guides1 and side rods connecting to the pump-rods4 ,two valves turned the steam on and off from under the piston1 with the ordinary gear and handles4 ,the boiler was similar to that for the winding engine1 but larger1 and had not the cylinder fixed in it2 a balance-beam regulated the movements1 as it had no great main beam1 and differed from ordinary engines just as the winding engine did4 ,the power was #cc horses1 and with an #aa-;inch pump barrel1 #aej feet of #aa-;inch pumps1 a winch1 and all apparatus necessary for draining the mine1 the cost was but #adjjl4 ,rough draft4 ,,plough ,,inn1 ,,blackwall1 ,december #bhth1 #ahac4 ,,mr4 ,,rastrick1 ,sir1--,i am requested by ,mr4 ,uville to write to you1 to push the boilers as fast as possible4 ,a ship will sail for the ,south ,sea fishery in about five weeks1 and will engage to take the whole of the engines4 ,we have not finally closed with her1 because we cannot state the exact time until we hear from you4 ,you must not lose a moment in sending the boiler to town4 ,i should have gone to ,cornwall before this1 but have been detained1 getting a ship2 and ,i do not like leaving until my agreements are executed1 which cannot be done until the beginning of next week4 ,i have been obliged to have all the transactions between the mines1 and the ,spanish ,government1 and ,mr4 ,uville1 translated into ,english1 before the outlines of an agreement could be drawn up1 which has been a most tedious job4 ,most of the people have been out of town1 and those that were not would do no business in the ,christmas1 which has occasioned a loss of near ten days4 ,as soon as the agreements are executed1 ,i will immediately send to you money from this place4 ,i have been kept so long here1 that it will not be worth returning to ,cornwall until after ,mr4 ,uville sails4 ,i shall be at ,bridgenorth in about ten days1 and will remain until the work is finished4 ,write how the work is getting on1 and what state the winding engine is in4 ,yours1 c41 ,,rd4 ,,trevithick4 ,rough draft4 ,,dear ,,sir1 ,,camborne1 ,march #dth1 #ahad4 ,your favour of the #bcrd ,february was sent to me from ,bridgenorth4 ,i have also received your favour of the #ast instant1 and will attend to the drawings you mention1 and be prepared to meet you as early as you please1 only give me as much notice as you can4 ,i hope by this time that ,mr4 ,page has done something toward the needful1 to be at your service4 ,i have1 agreeably with your letter this day1 desired ,capt4 ,thomas ,trevarthen to hold himself in readiness for ,london about the end of this month4 ,i have not yet seen ,bull4 ,i wish you to write me if ,i am to give him notice also to hold himself in readiness for town4 ,i fear that those two persons will not be sufficient to conduct the work with speed1 especially if ,capt4 ,trevarthen should be unwell2 he is a good miner and pitman1 and could assist in fixing the engines4 ,bull can only act as an assistant to an engineer1 therefore neither of them can take the sole direction of the work4 ,there will be those four large boilers to be put together on the spot1 which neither of those persons know but little about4 ,i think it would take a great charge and care from your mind to have a third person with you that could go through the whole of the undertaking1 especially as the distance from ,england is so great4 ,this undertaking of such immense magnitude and value ought not to depend solely on your own health1 as neither of the other two could get on without your assistance in laying down and planning the outline of the whole of the work belonging to the machinery4 ,if any one of the parts should be lost or broken1 it would require some ability in that country to contrive a substitute4 ,the expense of a third able man might prevent much loss of time and difficulty1 and would not be an object in a business of such a scale as you have commenced with4 ,i recommend a third person1 that you might count on a speedy and effectual start4 ,even in this kingdom1 where machinery is so well understood1 ,i have known several good undertakings fail1 from not employing at first an experienced engineer to conduct the work2 which ,i am doubtful would be the case at ,pascoe1 if you were not able to attend yourself to the erection1 and do not take a person with you for that purpose4 ,i beg your pardon for thus attempting to recommend to you a third person to go out2 but ,i think a work of this magnitude1 where expedition is important1 ought not to rest on the health of one man1 especially under a changeable climate4 ,please to consult your friends1 and give me your opinion on it in your next4 ,my health is much improved2 my wife desires her best respects1 and thanks for your present4 ,please to write soon4 ,yours1 c41 ,,rd4 ,,trevithick4 ,,mr4 ,,uville1 #ab1 ,east ,stien1 ,london4 ,rough draft4 ,,mr4 ,,page1 ,,camborne1 ,march #hth1 #ahad4 ,sir1--,yesterday ,mr4 ,joseph ,edwards1 of ,truro1 informed me that ,teague had given notice of trial1 and that the case would come on at the ,assize on the #bfth1 and requested me to desire you to write to him immediately1 and give him the whole of the transaction relative to ,mr4 ,uville's arrest in ,london4 ,he also wishes that some attention had been paid to the threat that ,mr4 ,uville received from ,teague's so-called friend1 so as to ascertain whether it came direct from him1 which he thought would have some weight in court4 ,i shall attend to give evidence at the ,assize with ,mr4 ,edwards4 ,i shall anxiously await a reply to my last4 ,how does ,harvey's business get on8 ,my respects to ,mr4 ,day1 and shall be very glad to find him recovering his health as fast as ,i am4 ,a crust of bread and clear air are far preferable to luxuries enveloped in clouds of smoke and heaps of filth4 ,your obedient servant1 ,,rd4 ,,trevithick4 ,p4,s4--,i hear that ,teague is still in ,london1 and that his furniture is removed to his friend's house1 to save it from the hands of surrounding evil spirits4 ,trevithick showed no undue amount of discontent on discovering that ,uville had led him into pecuniary difficulties1 and even his tendency to interfere in engineering matters was not hastily resented4 ,in ,december1 #ahac1 while in ,london1 arranging for a vessel to convey the engines to ,lima1 and also to secure written agreements with ,uville1 who expected to leave ,england in a week or two1 the going into the documents made known many weak points1 one of them being shortness of money4 ,the expected week or two had lengthened out to three months1 and ,uville was still in ,london1 and ,capt4 ,thomas ,trevarthen and ,bull were to be there1 ready to start1 about the middle of ,march1 #ahad4 ,four large boilers1 in pieces1 were to go for the pumping engines1 to be put together in the mines2 and ,trevithick strongly recommended the sending a third man1 to take general charge of the practical work1 which ,mr4 ,uville thought he himself could manage4 ,page and ,day were lawyers1 who drew up very long documents4 ,money to pay expenses was raised by the sale of shares in a company formed by ,uville without sufficient authority1 and ,page was to go to the mines to look after his own and the ,english shareholders' interests2 between them ,uville was arrested1 apparently for some trifle4 ,rough draft4 ,,mr4 ,,uville1 ,,camborne1 ,march #aeth1 #ahad4 ,sir1--,i shall write to him again by this post1 and push him to send down the transfer of my shares1 already agreed on1 for my execution1 and hope ,i shall be able to meet ,messrs4 ,hazeldine and ,co4's demand before it will be due4 ,the young man ,bull has been with me4 ,i told him ,i expected that you intended to take him with you1 and ,capt4 ,trevarthen is making preparation for going4 ,i am glad you intend to take a third person with you4 ,i have not thought or said anything to anyone about this business4 ,mr4 ,vivian informed me that1 from the conversation he had with you on the subject1 he had expected to hear from you4 ,i can answer for ,mr4 ,vivian's honesty1 ability1 and pleasant behaviour1 and he is a person very suitable for the engagement1 only that one failing of making too free with an evening glass1 which you were not unacquainted with while in ,cornwall at ,dolcoath ,mine4 ,i do not like to take an active part in this business1 because if any accident should happen to him1 my sister or his family might charge me with being accessory to his going2 therefore ,i must beg to be exempt from taking any part in this engagement4 ,i remain1 ,sir1 yours1 ,,rd4 ,,trevithick4 ,rough draft4 ,,mr4 ,,page1 ,,camborne1 ,april #ith1 #ahad4 ,sir1--,i have your favour of the #eth instant4 ,i intend to be in town on ,sunday week1 but this need not prevent their writing to me here2 and both you and they may still be doing your best towards disposing of shares4 ,your obedient servant1 ,,rd4 ,,trevithick4 ,rough draft4 ,,mr4 ,,uville1 ,,camborne1 ,april #ith1 #ahad4 ,sir1--,i intend to be in ,london on ,sunday1 the #agth1 and shall call immediately on this person for money1 which shall be at your service4 ,wheal ,alfred and ,wheal ,prosper agents wish you a prosperous voyage1 and success in your mines4 ,i remain1 ,sir1 ,your obedient servant1 ,,rd4 ,,trevithick4 ,trevithick was now embarked with a crew of speculators1 and in payment for his services was made a partner1 and sold a portion of his shares to pay for the engines which ,uville had ordered4 ,henry ,vivian1 his brother-in-law1 and the brother of his late partner ,andrew ,vivian1 wished to be the third person engaged to go with the machinery to ,america4 ,trevithick spoke of his honesty and ability1 but declined1 on account of the family relationship1 to take any part in the appointment4 ,the two notes on the #ith ,april1 #ahad1 close the correspondence4 ,page was busy selling shares to raise money1 and ,trevithick was to get some money1 which was to be at the service of ,uville4 ,the delay between this period and the time of starting was mainly caused by financial and other arrangements managed by ,uville4 ,on the #ast ,september1 #ahad1 ,uville1 ,henry ,vivian1 ,thomas ,trevarthen1 and ,william ,bull sailed from ,portsmouth for ,lima in the ',wildman1' taking with them four pumping engines1 with pump-work and rods complete2 four winding whim-engines1 with all winding apparatus complete2 one portable locomotive engine on wheels1 to be used for a rolling mill or other purposes2 one mill for grinding ore2 and one rolling mill1 probably for the ,mint at ,lima4 ,these nine steam-engines1 with their apparatus complete for work at the mines1 cost #fhchl42 the grinding and rolling mill cost #gjjl4 more2 but various other expenses more than doubled the amount1 which reached the large sum of over #af1jjjl4 ,on reference to the conditions of agreement under which ,uville acted1 dated #agth ,july1 #ahab1 ,don ,pedro ,abadia1 ,don ,jos ,arismendi1 and ,don ,francisco ,uville1 were partners engaging to drain a range of mines4 ,uville was to go to ,london to purchase two steam-engines1 and was authorized to expend #cj1jjj 7say #fjjjl474 #bjjj 7say #djjl47 was to be paid to him as the value of ,trevithick's model1 which he had a few years before bought in ,london for #bal4 ,he was to engage one or two ,english workmen4 ,no new partner was to be allowed4 ,they also contracted with the various workers of mines in ,yauricocha1 ,yanacancha1 ,caya ,chica1 ,santa ,rosa1 and in the mining ridge of ,colquijilca1 for a period of nine years1 to commence within eighteen months of that time1 to sink a general pit for the drainage of those mines1 and to pump out the water by steam-engines4 ,the payment for this drainage was to be one-twentieth part of the ore raised by the different mines4 ,an agreement made at ,london this #hth day of ,january1 #ahad1 between ,don ,francisco ,uville1 of ,lima1 in the ,viceroyalty of ,peru1 of the one part1 and ,richard ,trevithick1 of ,camborne1 in ,cornwall1 engineer1 of the other part4 ,whereas1 by an agreement of partnership made and signed at ,lima1 and whereas the said ,francisco ,uville did in pursuance of his contract with the said miners soon after the ratification thereof1 embark for ,england1 for the purpose of fulfilling the same on his part1 and on his arrival there in the month of ,april last1 made application to the said ,richard ,trevithick1 who is an experienced engineer and miner1 and requested him to assist him in promoting the object of his journey1 which the said ,richard ,trevithick 7being penetrated with a high sense of its utility7 agreed to do1 and hath accordingly applied himself wholly to that object1 ever since the arrival of the said ,francisco ,uville in ,england3 ,and whereas under the direction of the said ,richard ,trevithick1 and by the orders of the said ,francisco ,uville1 various machines and engines have been made for the purposes of the said concern1 a part of which has been already paid for by the said ,francisco ,uville2 but several of the bills brought by him to ,england not having been honoured1 by reason of the absence from ,england of the parties upon whom they were drawn1 the said ,francisco ,uville hath not at present sufficient funds to answer the engagements he has entered into in this country1 and ,don ,juan 4419999 to whom he was in that case directed by his partners to offer shares in the said concern1 and from whom he could have received supplies1 not being at this time in ,london1 the said ,francisco ,uville has agreed to admit the said ,richard ,trevithick to be a partner in the concern1 upon his advancing and paying a proportionable part of the expenses necessary for carrying on the same4 ,now these presents witness that in consideration of the said ,richard ,trevithick having paid and agreeing by these presents to pay certain bills for machinery ordered by the said ,francisco ,uville to the amount of #cjjjl4 or thereabouts1 the particulars of which have been ascertained and settled by and between the said ,francisco ,uville and ,richard ,trevithick1 and also in consideration of the services which the said ,richard ,trevithick hath already rendered to the said undertaking1 and of the future benefits which he is expected to perform for it1 the said ,francisco ,uville for himself1 and on the behalf and in the name of the said ,pedro ,abadia and ,jos ,arismendi 7who will ratify these presents in the capital of ,lima as soon as it shall be produced to them1 to which the said ,uville holds himself bound71 ,doth1 by virtue of the power and authority given to him by his said partners1 agree to admit the said ,richard ,trevithick to be a member of the said company1 and doth hereby declare him to be a member thereof and a partner therein to the extent of #ab1jjj dollars1 and as such1 entitled to a share and interest in all the profits and advantages of the company in the proportion which the said sum of #ab1jjj dollars shall bear to the amount of capital employed by the company in the purposes of their establishment1 which proportion will amount as nearly as can now be ascertained to one-fifth of the capital stock embarked in the said concern4 ,,fran4 ,,uville4 ,,richard ,,trevithick4 #hth ,january1 #ahad4 ,so ,trevithick paid #cjjjl4 and received nothing for his engineer's work1 to be made a partner1 contrary to ,uville's limit of authority1 in a speculation that proved to be not worth a farthing4 ,the following is a summary of the detail invoice of engines and machinery which left ,london for ,lima in ,september1 #ahad1 in charge of ,uville1 just fifteen months after his landing at ,falmouth in search of ,trevithick3-- ,invoice of four steam-engines1 four winding engines1 one portable rolling engine and materials for ditto1 two crushing mills1 four extra-patent boilers1 spare materials for engines1 boring rods1 miners'1 blacksmiths'1 and carpenters' tools1 c41 shipped on board the ',wildman1' ,john ,leith1 master1 from ,london to ,lima1 by1 on account and risque of ,don ,francisco ,uville1 ,don ,pedro ,abadia1 and ,don ,jos ,arismendi1 merchants at ,lima4 ,dated #ahad4 ,to four steam-engines of #cc-;horse-power each s4 d4 7complete for lifting water with under-adit and house lift-pumps1 and wrought-iron pit-work1 rods1 c41 at #aciil4 #acs4 each #e1eih #ab #j ,to four winding engines of #h-;horse-power each1 with whims1 barrels1 shafts1 c41 complete for lifting ore1 at #bajl4 each #hdj #j #j ,to one portable steam-engine of #h-;horse power1 for rolling1 with its chimney1 axles1 carriage-wheels1 c4 #djj #j #j ----------- #f1hch #ab #j ,a mill for grinding ore #eag #j #j ,a rolling mill #bjd #j #j ,duplicates1 sundries1 freight1 insurance1 c41 c4 #h1eib #i #a ------------- #i1cac #i #a ------------- #af1aeb #a #a ,the nine steam-engines1 including a locomotive1 with its chimney1 axles1 carriage-wheels1 c41 a crushing mill and a rolling mill1 cost but #gefjl4 ,other expenses1 for freight1 insurance1 c41 c41 increased the amount to #af1aebl4 ,william ,williams1#abc on his return from the ,cerro de ,pasco ,mines1 states3-- ,footnote #abc3 ,residing at ,angarrack1 near ,hayle1 #ahgb4 ,on the #crd ,march1 #ahgb1 ,i saw in ,yauricocha ,mine two of ,mr4 ,trevithick's engines at work2 one of them was a horizontal #ab-;inch open-top cylinder pumping engine1 about a #d-;feet stroke2 there were two fly-wheels about #aj feet diameter and a cog-99wheel #g feet diameter1 giving motion to two wrought-iron beams working a #aj-;inch pump bucket4 ,the other was a #ab-;inch cylinder winding engine with a large fly-wheel4 ,three ,cornish boilers1 about #e feet #f inches diameter1 with #c feet #i inch tube1 #cj feet long1 made of #g_/afths of an inch plates1 supplied steam of #dj lbs4 on the inch4 ,,chapter ,,xxii4 ,,peru4 ,conditions under which ,don ,pedro ,abadia1 ,don ,jos ,arismendi1 and ,don ,francisco ,uville1 establish the project of draining the mines by means of steam-engines1 to be brought from ,england4 #ast4 ,the company is composed of three contracting persons without admitting therein any other whatever4 #bnd4 ,there are intended as a fund for the undertaking #dj1jjj dollars1 to be divided into four shares in the following manner3--,two shares to ,don ,pedro ,abadia1 one to ,don ,jos ,arismendi1 one to ,don ,francisco ,uville4 ,four shares1 dollars #dj1jjj4 #eth4 ,these principles of good faith and friendship being established1 the project is to be carried into effect with the greatest possible activity1 for which purpose1 by the first opportunity1 the funds shall be forwarded by ,don ,pedro ,abadia to the amount of #cj1jjj dollars1 with the necessary instructions for the construction of the machinery to a person who may be appointed4 #gth4 ,as it has been estimated that #cj1jjj dollars will cover the cost of two engines in ,england1 if the said ,uville finds another on credit1 he is authorized to purchase it on account of the company4 #aath4 ,should the undertaking yield profits1 ,uville shall also be credited for #bjjj dollars for the value of the model4 #abth4 ,in the instructions that may be given to ,uville1 it shall be stipulated on what terms he may engage one or two ,english workmen4 ,,lima1 #agth ,july1 #ahab4 ,contract4 #ast4 ,the present contract shall be considered binding for nine years1 to be computed from the time the steam-engines may be erected in the different parts of these mines that may be judged suitable4 #bnd4 ,the miners herein contracting cede their mines in ,yauricocha1 ,yanacancha1 ,caya ,chica1 ,santa ,rosa1 and in the mining ridge of ,colquijilca1 and the company offer the means1 steam-engines1 and instruments for draining the same1 and on these principles the obligations of both parties are as follow1 to wit4 #crd4 ,the company binds itself within the period of eighteen months1 or sooner if possible1 to bring over the steam-engines to drain successively the different parts of these mines1 and immediately on their arrival to place them in ,yauricocha1 and afterwards in ,yanacancha1 ,caya ,chica1 ,santa ,rosa1 and in the mining ridge of ,colquijilca1 to sink a general pit for the collection of the waters at a depth of #dj varas from the adit or drainage level of ,santa ,rosa4 #hth4 ,each miner whose mine situated in the parts above specified is not perfectly drained in consequence of the filtration or natural gravity of the water to the general pit1 is to continue a tube to communicate with the said general pit on his own account1 in order fully to enjoy the benefit of the draining1 it being well understood that the company shall not refuse to admit the waters of any of the mines situated in this part whatever their quantity may be4 ,and the company shall be further bound to supply funds to any miner who may not have sufficient to defray the expenses of such tube of communication at an interest of #f per cent41 to be refunded out of the first metals which may be obtained4 #ajth4 ,the recompense to be made to the company for the general drain procured in the place or places agreed on1 shall be1 with regard to ,yanacancha and ,yauricocha1 in consequence of the known richness of those places1 and of the timber required by the softness of the ground to secure the mines1 #ae per cent4 on the ore that shall be extracted therefrom1 and lodged either in the common depots or in the respective warehouses2 and in the mines of ,santa ,rosa1 ,caya ,chica1 and ,colquijilca1 #bj per cent41 which distribution is respectively to be made on the quantities obtained4 #adth4 ,that the miner who refuses to enter into this fair contract whose mines are benefited by the means of the engines1 shall be compelled to pay the contributions and to perform what has been therein stipulated according to ordinance4 ,this contract being agreed to1 the contracting parties signed respectively to be bound and compelled2 and ,i1 the ,royal ,judge and ,sub-delegate hereof for ,his ,majesty1 signing it with all the contracting parties and witnesses before me on the said day1 month1 and year4 ,pedro ,abadia1 ,jos ,arismendi1 ,francisco ,uville1 ,jos ,maria de ,ulloa1 ,ignacio ,beistequi1 ,the ,marquis de la ,real ,confianza1 ,jos ,herress1 ,publo ,anellfuertes1 ,ramon ,garcia de ,purga1 ,jos ,antonio de ,arrieta1 ,jos ,camilo de ,mier1 ,jos ,lago y ,lemus4 ,for myself and ,don ,remiqia1 p4 procuration ,manuel ,queypo1 ,rafael ,doper1 ,juan ,gonzalez1 ,augustin ,zambrano1 ,francisco ,rasines1 ,francisco ,fuyre1 ,manuel ,ysasi1 ,alberto de ,abellaneda1 ,ysidro ,crespo1 ,juan ,antonio ,arrasas1 ,pedro ,gusman1 ,manuel ,yglesias1 ,patricio ,bermudez1 ,bartolome de ,estrada4 ,for the miners1 ,don ,castano ,villanueva1 ,juan ,isidoro1 ,manuel de ,santalla1 ,juan ,palencia1 ,antonio ,perez1 ,manuel ,cavellero1 ,domingo ,pallacios1 ,matias ,canallero1 ,ambrosio ,ortega1 ,francisco de ,otayequi1 ,pedro de ,arrieta1 ,juan de ,erquiaga1 ,jos ,zeferino ,abaytad1 ,antonio ,villaseca1 ,estanislas ,maria de ,arriola1 ,jos ,maria del ,veto1 ,ambrosio ,guidones1 ,santiago ,oreguela4 ,for ,don ,pedro ,mirales1 p4 procuration1 ,thomas ,hidalgo1 ,nicholas ,berrotarran1 ,barnabe ,perez de ,ybarrela1 ,augustin ,bayroa1 ,francisco ,xavier de ,uribe1 ,manuel ,varela4 ,for my brother1 ,juan ,francisco de ,aspiroz1 ,juan ,miguel de ,aspiroz4 ,in the city of ,los ,reyes on the #bfth ,september1 #ahab4 ,these extracts from an agreement drawn up by the leading men in ,peru in #ahab are proofs of remarkable energy4 ,rumours of the power of steam-engines used in mines in ,england had reached ,lima1 ,don ,francisco ,uville was sent on a mission of inquiry1 and in #ahaa consulted ,boulton and ,watt at ,soho1 who gave an opinion that their engines were not suitable to so elevated a position where the atmosphere was so much lighter than in ,england1 and the difficulties of transit so great4 ,on his return to ,lima he carried with him a small model of ,trevithick's high-pressure steam-engine4 ,the ,spaniards on seeing it work had the good sense and courage to put aside the ,watt report and adopt the principle of the small but active high-pressure steam-puffer engine4 ,an influential company was formed1 which sent ,uville again to ,england to seek out the high-pressure engineer and purchase his engines4 ,what stronger evidence could be given of the great difference between the rival engineers and their engines8 ,the one with low-pressure steam and vacuum1 the other with high-pressure steam and without vacuum4 ,the three persons contracting to drain the ,peruvian mines agreed that no other should be allowed to join them in the contract2 two steam-engines were to be purchased1 and if convenient a third engine might be ordered on credit4 ,one or two ,english mechanics were to accompany the engines which the contractors engaged should be in ,lima within eighteen months4 ,ten months had passed before ,uville reached ,trevithick1 and when in ,may1 #ahac1 he communicated to the ,cornish engineer the same wants that he had made known to ,watt two years before1 how different was the answer received4 ,i engage to supply in four months six #bd-;inch cylinder high-pressure steam pumping engines1 with pumps and all necessary apparatus complete4#abd ,this promise was nearly fulfilled1#abe but want of money1 the ordering of additional machinery1 and difficulty in finding a ship1--for ,spain was then at war1 or on the verge of it1 with the ,south ,american republics1--delayed for a time the completion of the order2 but within eight months even the additional work seems to have been ready1 and the following agreement was entered into1 though the ship with her freight of nine steam-engines did not leave ,england until ,september1 #ahad1 fifteen months after ,uville's first meeting with ,trevithick4 ,footnote #abd3 ,see ,trevithick's letter1 #bbnd ,may1 #ahac1 vol4 ii41 p4 #aih4 ,footnote #abe3 ,see ,trevithick's letters1 #bbnd ,sept4 and #bcrd ,oct41 #ahac1 vol4 ii41 pp4 #bjf1 #bji4 ,agreement dated the #hth ,january1 #ahad4 ,the said persons from whom he 7,uville7 would have received supplies1 not being at that time in ,london1 the said ,francisco ,uville has agreed to admit the said ,richard ,trevithick to be a partner in the concern1 upon his advancing and paying a proportionable part of the expenses necessary for carrying on the same4 ,now these presents witness1 that in consideration of the said ,richard ,trevithick having paid1 and agreeing by those instruments to pay certain bills for machinery ordered by the said ,francisco ,uville to the amount of #cjjjl41 and also in consideration of the services which the said ,richard ,trevithick hath already rendered1 and of the future benefits which he is expected to perform1 doth agree to admit the said ,richard ,trevithick a partner therein1 as nearly as can be ascertained to one-fifth share of the whole4 ,he hath planned and directed the particular construction of three steam-engines1 and hath for that purpose taken many journeys to manufacturing towns and other places4 ,he hath given to the said ,francisco ,uville a general knowledge of ,english mining1 miners' tools1 winding and crushing engines1 c41 c41 and for that purpose hath taken him to various mines in ,england1 to which the said ,richard ,trevithick1 through his interest1 had access4 ,he hath instructed the said ,francisco ,uville in the art of making drawings of mines1 and in engineering4 ,he hath furnished him with various drawings of ,english mines1 and plans for the future working of ,spanish mines1 and hath given to him every other engineering and mining information4 ,he hath increased the power of the three engines above mentioned to the extent of one full third1 without making any additional charge for so doing1 and he hath agreed to supply the said company with a fourth engine1 and to wait for the payment of it1 until the return of the said ,francisco ,uville to ,lima1 in recompense for all which the said ,francisco ,uville doth for himself and his partners grant to the said ,richard ,trevithick one and quarter per cent4 of the net produce or profits 7all expenses first deducted7 of the ore extracted from the said mines1 and as a further recompense1 doth appoint him sole engineer in ,europe for all the machinery that shall be used or required4 ,the nine steam-engines1 with apparatus for minting1 crushing ores1 draining1 winding1 and even locomotion1 with miners' tools complete down to mine ladders1 borers1 picks and gads1 and hammers1 were received by a large and influential body of ,spaniards residing near ,lima1 under the special patronage of the ,viceroy4 ,the machinery had then to be taken up precipitous tracks that foot-passengers trembled to walk on1 to the height of more than #ae1jjj feet4 ,the calculated profit was #ejj1jjjl4 a year1 of which #ajj1jjjl4 a year was to be ,trevithick's share1 a portion of which was sold to pay for the engines4 ,a prospectus drawn up in ,england states that the whole capital was in four hundred shares1 of which ,trevithick held eighty1 valued at #dj1jjjl41 together with special advantages to be accorded to him4 ,the machinery having left ,england in ,september1 #ahad1 reached ,peru in the early part of #ahae1 shortly after which one of the engines was at work in the ,mint at ,lima1 within two years from the giving the order for it in ,england2 for in the early part of the latter year ,trevithick wrote to one of his men3-- ,i am sorry to find by ,mr4 ,uville's letter that the ,mint engine does not go well4 ,i wish you had put the fire under the boiler and through the tube1 as ,i desired you to do1 in the usual way of the old long boilers1 then you might have made your fire-place as large as you pleased1 which would have answered the purpose1 and have worked with wood as well as with coal1 and have answered every expectation4 ,i always told you that the fire-place in the boiler was large enough for coal1 but not for wood1 and desired you to put it under it4 ,the boiler is strong enough and large enough to work the engine thirty strokes per minute1 with #cj lbs4 of steam to the inch4 ,i hope to leave ,cornwall for ,lima about the end of this month1 and go by way of ,buenos ,ayres1 and cross over the continent of ,south ,america1 because ,i cannot get a passage2 none of the ,south ,sea whalers will engage to take me to ,lima1 they say that they may touch at ,lima or they may not1 in the whole course of their voyage2 therefore1 unless ,i give them an immense sum of money for my passage1 they will not engage to put me on shore at ,lima1 and for me to risk a passage in that way1 and to be brought back again to ,england after two years' voyage1 without seeing ,lima1 would be a very foolish trip2 therefore to make a certainty1 ,i shall take the first ship for ,buenos ,ayres1 preparations for which ,i have already made4#abf ,footnote #abf3 ,unfinished rough draft of letter by ,trevithick4 ,the whole of the machinery having been sent off1 ,trevithick was prepared to make his way across the then little-known continent of ,south ,america in its broadest part1 from ,buenos ,ayres to ,cerro de ,pasco4#abg ,his departure was deferred from various causes until the #bjth ,october1 #ahaf1 when he sailed from ,penzance in the ,south ,sea whaler ',asp1' ,capt4 ,kenny4 ,footnote #abg3 ,see ,trevithick's letter1 ,december #ith1 #ahae1 vol4 ii41 p4 #ca4 ,illustration3 ,,penzance ,,in ,,olden ,,time4 ,w4 ,j4 ,welch4 ,,dear ,,sir1 ,,penzance1 #bjth ,august1 #ahag4 ,i am enabled to furnish you with a few particulars which led to the introduction of steam-engines into ,spanish ,america1 which you will embody into your interesting paper for our next ,geological meeting1 as you deem most proper4 ,captain ,trevithick was born in ,illogan1 ,cornwall1 #agga1 but he has generally resided at ,camborne1 the adjoining parish4 ,he has devoted the greatest part of his life to mechanics and to improvements in the high-pressure steam-engine1 and many engines of ,captain ,trevithick's construction are now working in different parts of ,england4 ,mr4 ,francisco ,uville1 a native of ,switzerland1 visited ,lima and the rich ,peruvian mines in the neighbourhood of ,lima1 at an early age1 and being a gentleman of great intelligence1 he thought it possible that the silver mines at ,pasco1 about #aej miles from ,lima1 which were fast falling into decay for want of machinery to drain the water1 might be restored to their former celebrity by the introduction of steam-engines4 ,mr4 ,uville1 who is now about thirty-six years of age1 came to ,england in #ahaa1 where he continued a few months1 and just as he was about to leave ,london he observed by accident a model of a steam-engine1 made by ,captain ,trevithick1 at the shop of a ,mr4 ,roland1 ,fitzroy ,square1 and ,mr4 ,uville so much liked the simplicity of its construction1 that he immediately purchased it at twenty guineas4 ,mr4 ,uville returned to ,lima with it1 and tried it on the mountains of ,pasco1 in consequence of which1 on the #agth of ,july1 #ahab1 ,mr4 ,uville1 with ,don ,pedro ,abadia and ,don ,jos ,aresmendi1 eminent merchants at ,lima1 were so confident of success1 that they formed a company to drain the mines at ,pasco and its vicinity2 and on the #bbnd of ,august then following a contract was entered into by these gentlemen and the proprietors of the mines in that district4 ,soon after which ,mr4 ,uville was deputed by the company to return to ,england and to find out some able engineer to assist him in procuring proper steam-engines to be conveyed to the mines4 ,uville having put into ,jamaica1 came to ,england in the ',fox' packet1 ,capt4 ,tilly1 and arrived at ,falmouth early in the summer of #ahac4 ,during the passage ,mr4 ,uville frequently talked of the object of his voyage1 and that he was particularly anxious to find out the maker of the model of the engine he took to ,lima1 and recollecting that the name of ',trevithick' was on the model1 he mentioned it to a ,mr4 ,teague1 who happened to be on board the packet1 when the latter informed him that ,capt4 ,trevithick was his first cousin1 and that he resided within a few miles from ,falmouth4 ,immediately on ,mr4 ,uville's arrival an interview took place between him and ,capt4 ,trevithick1 and soon after ,mr4 ,uville removed to ,capt4 ,trevithick's house in ,camborne1 where he resided several months1 during which time ,capt4 ,trevithick instructed him in mining1 machinery1 c4 ,capt4 ,trevithick and ,mr4 ,uville1 after seeing most of the mines in ,cornwall1 visited several other mining districts in ,england1 to afford ,mr4 ,uville a better opportunity of acquiring the best knowledge of engineering by examining the steam-engines erected4 ,afterwards they went to ,london1 when ,mr4 ,uville was introduced to a ,mr4 ,campbell1 of the ,east ,india ,company's department4 ,mr4 ,campbell informed ,mr4 ,uville that the best engineers in ,europe were ,messrs4 ,boulton and ,watt1 of ,birmingham2 and strongly recommending them to him1 he observed that he was convinced if engines could be made capable of being transported to the mines of ,pasco across the mountains they would be able to do it4 ,mr4 ,uville accordingly applied to these gentlemen1 and fully explained to them the nature of the engines which would be wanted1 and the state of the road by which they must be conveyed1 and ,messrs4 ,boulton and ,watt returned an answer that it would be impossible to make engines small enough to be carried across the ,cordillera to the mines4 ,capt4 ,trevithick1 however1 was not startled at the difficulties1 and having applied himself to the improvements of his high-pressure engines1 entered into a contract with ,mr4 ,uville to provide nine steam-engines for the company at ,lima2 and1 by virtue of the powers with which ,mr4 ,uville was invested1 ,capt4 ,trevithick was admitted a partner of one-fifth in the concern2 besides which1 for his great pains and services he had rendered1 ,mr4 ,uville guaranteed to him a handsome percentage on the profits of the company 7vide ,articles of ,agreement of #hth ,january1 #ahad74 ,these matters being settled1 nine engines were provided at an expense of about #aj1jjjl41 and were shipped on board the ',wildman1' ,south ,sea whaler1 ,capt4 ,leith1 who sailed from ,portsmouth for ,lima the #ast ,september1 #ahad1 accompanied by ,mr4 ,uville and the following ,cornish engineers1--,thomas ,trevarthen1 of ,crowan2 ,henry ,vivian1 of ,camborne2 and ,william ,bull1 of ,chacewater1 in ,gwennap4 ,the engines arrived at ,lima1 and were received by a salute from the ,government batteries1 and the greatest joy was testified on the occasion4 ,on the #bgth ,july1 #ahaf1 the first steam-engine was set to work at ,santa ,rosa1 one of the mines of ,pasco1 under the direction of ,mr4 ,bull 7vide despatch of that date1 signed ,jos ,g4 de ,prada74 ,on the #bjth ,october1 #ahaf1 ,capt4 ,trevithick sailed for ,lima in the ',asp1' ,south ,sea whaler1 ,capt4 ,kenny1 accompanied by ,mr4 ,page1 a gentleman of ,london1 and ,james ,saunders1 of ,camborne1 an engine maker2 and on the #fth ,february1 #ahag1 they arrived at ,lima1 where ,capt4 ,trevithick was immediately introduced to the ,viceroy by ,don ,p4 ,abadia1 and he received the most marked attention from the inhabitants 7vide ',lima ,gazette' of #abth ,february74 ,perhaps you will think it proper to notice the furnaces which ,captain ,trevithick took out in the ',asp' to ,lima for the purpose of purifying the silver by sulphur4 ,a great expense will be saved by these means4 ,any further information which ,i can afford you ,i will readily give4 ,i am1 dear ,sir1 ,your very obedient and humble servant1 ,,rd4 ,,edmonds4 ,h4 ,f4 ,,boaze1 ,esq4 ,this statement1 from a solicitor more than fifty years ago1 inadvertently points out the difference between the steam-engine of ,watt and that of ,trevithick4 ,the former said it was impossible to make engines having the required power small enough to be carried to the mountain mines1 whereas a small high-pressure engine by the latter had sufficient power4 ,day and ,page were lawyers advising ,mr4 ,uville in ,london4 ,page sailed from ,penzance with ,trevithick and ,james ,saunders1 a boiler maker1 in the ',asp1' a ,south ,sea whaler1 on the #bjth ,october1 #ahaf1 just two years after the departure of ,uville with the machinery and engines4 ,the difficulty of conveying heavy weights up the mountain foot-paths was almost insurmountable4 ,mr4 ,rowe1 who went to these mines in #ahej1 says1-- ,the ,cerro de ,pasco mines are about #agj miles from ,lima2 we crossed a ridge #be1jjj feet high4 ,the mines were about #ac1djj feet high above the sea4 ,there was but one road2 no wheel vehicle could be used2 everything was carried on mules4 ,sometimes the road was only #b-a_/b feet wide1 cut in precipices three or four hundred feet perpendicular3 some of the men were afraid to walk1 and dared not ride4 ,i lived in the house that used to be ,mr4 ,trevithick's office and store-room2 it was in the suburbs of the town of ,cerro de ,pasco4 ,the shafts are some of them in the middle of the town2 several pieces of ,captain ,trevithick's engines lay about the shafts1 and some on the way up1 as though they had stuck fast1 and some we saw at ,lima4 ,mr4 ,jump1 a director on the mine1 pointed out a balance-beam that ,mr4 ,trevithick had put up thirty years before4 ,only one ,englishman then remained there who had worked for ,mr4 ,trevithick2 he was called ,sycombe1 and said ,trevithick's men were an unmanageable lot4 ,the natives worked in the mines underground4 ,the atmosphere was only about #aj lbs4 on the inch4 ,we found a coal mine not far off2 the quality was not very good4 ,the smiths had difficulty in welding with it4 ,our heaviest pieces of machinery did not exceed #bhj lbs4 ,the worst parts of the road have been a little improved since that time4 ,just one month before ,trevithick sailed from ,penzance for ,lima1 the first pumping engine taken out by ,uville had been satisfactorily put to work in the mountain mine of ,santa ,rosa1 with its steam-cylinder weighing double the limit fixed on by modern engineers4 ,the following information respecting the progress of the steam-engine fixed on the ,santa ,rosa ,mines1 one of the mineral ridges of ,pasco1 in the ,viceroyalty of ,peru1 is extracted from the ,government-,gazettes of ,lima1 dated the #ajth of ,august and #beth of ,september1 #ahaf3-- ,,progress ,,of ,,the ,,steam-,,engine1 c4 ,his ,excellency the ,viceroy of ,peru to the ,editor4 ,in order to satisfy the eager expectations of the inhabitants of this ,viceroyalty1 those of the greater part of these ,americas1 and even of the ,peninsula itself1 ,i hereby order the printing1 at full length1 in the next ,government ,gazette1 or at same time in a separate sheet1 the enclosed despatch from the ,intendant ,governor of ,tarma1 giving the details of the admirable results of the steam-engine fixed in the mineral territory of ,pasco1 for the most important purpose of draining its mines1 and for the extraction of its rich ores4 ,this authentic communication must produce the most lively and grateful sensations in those true ,spaniards1 who with grief contemplated as irreparably lost the only spring from which flowed the prosperity of this continent1 excite their just acknowledgments to the meritorious co-operators in such an expensive and difficult as well as eminently-advantageous enterprise1 and encourage to similar undertakings in other parts those who1 with personal aptitudes and patriotic sentiments1 have been waiting the final success of the first4 ,,joaquin ,,de ,,la ,,pezuela4 ,,lima1 #dth ,august1 #ahaf4 ,certificate of the ,deputation4 ,we1 ,don ,domingo ,gonzales de ,castaeda and ,don ,jos ,lago y ,lemus1 ,commissaries and ,territorial ,magistrates in this ,royal ,mineral ,territory1 and deputed by the ,united ,corporation of ,miners in this district1 do hereby certify judicially1 and as the law directs1 in manner following3-- ,though this deputation never doubted the extraordinary power of steam compressed1 and consequently the certain operation of engines worked by its influence1 it nevertheless entertained some fears respecting the perfect organization of all the mechanical powers of the machines4 ,this uncertainty1 rather than any doubt1 has been completely dissipated by our personal attendance this day to witness the draining of the first pit1 situated in ,santa ,rosa4 ,the few instants employed in the same produce a full conviction that a general drainage of the mines will take place1 and that their metals will be extracted with the greatest facility from their utmost profundity3 as also that the skill of the company's partners and agents will easily overcome whatsoever difficulties nature may oppose1 until they shall have completed all the perpendiculars and levels2 and consequently that the meritorious undertakers who have risked their property in the enterprise will be rewarded with riches4 ,we and the whole ,corporation of ,miners would do but little were we to erect them a monument1 which should transmit down to the remotest posterity the remembrance of an undertaking of such magnitude and heroism2 but for the present we will congratulate ourselves that our labours1 co-operation1 and fidelity1 keeping pace in perfect harmony with the exertions of the agents1 the company may thus attain the full completion of their utmost wishes1 extracting from the bowels of these prolific mountains1 not the riches of ,amilcar's inexhaustible wells1 not the treasures of the boasted ,potosi in its happiest days1 but a torrent of silver1 which will fill all surrounding nations with admiration1 will give energy to commerce1 prosperity to this ,viceroyalty and to the ,peninsula1 and fill the royal treasury of our beloved sovereign4 ,thus certifies this ,magisterial ,deputation of ,yauricocha1 the #bgth of ,july1 #ahaf4 ,,domingo ,,gonzales ,,de ,,casta,,eda4 ,,jos ,,lago ,y ,,lemus4 ,despatch from the ,intendant ,governor of the ,province of ,tarma to ,his ,excellency the ,viceroy4 ,,most ,,excellent ,,sir1 ,,pasco1 #bgth ,july1 #ahaf4 ,having finally conquered the great difficulties consequent on the enterprise1 though with immense and incessant labour1 and at an enormous expense1 the object has been accomplished of purchasing1 importing1 and erecting the steam-engine in the celebrated rich and royal mineral territory1 called ',the ,mountains of ,yauricocha1' in this province of ,tarma1 of which ,i have the honour to be ,governor1 the chief and valuable works of which have ceased to produce ore1 in consequence of their bases being completely submerged in water4 ,the day is arrived when we witness with admiration the advantageous and useful effects of the before-named steam-engine2 the completion of the promises made by the generous and undaunted individuals who united themselves to supply the funds sufficient for the realization of an enterprise so important1 and the fulfilment of the wishes of these valuable subjects1 to render to the ,state the highest possible service2 a service1 although at all times of extreme importance1 at this crisis is infinite2 because the ,state1 being weakened by a series of disastrous events for six years past1 requires salutary remedies2 and none exist so effectual as the re-establishment of the mines1 which the steam-engines are achieving4 ,after some experiments1 which 7although they left no doubt of ultimate success in draining the mine7 discovered some slight defects1 these were corrected on the #bcrd instant2 and this day the first of the four pumps which arrived for the use of the royal mines was erected in the particular mine called ,santa ,rosa2 the result of its operation has been the exhaustion of the water from the well or hollow below the adit4 ,in twenty minutes1 by this engine1 an aggregate of water is ejected amounting to #f yards or #ah feet in diameter1 #c yards #bd inches in length1 and #a yard #cj inches in breadth4 ,in the same manner a second engine1 accessory to that which drains the water1 is worked by the same steam1 on the same point1 and in the same perpendicular shaft1 from the surface of the earth1 which extracts the ore1 and with advantages hitherto unknown here1 on account of the considerable saving of expense and the economy of manual labour4 ,the steam-engine will continue evacuating the water from the pit until it is reduced to #f yards below the old adit1 whence they must eject the water raised by the engine by a continued elongation of the barrel of the pump gaining depth1 until they have completed the number of yards required1 or until the progress of the work indicates a proper situation for forming a new line of levels and channels of communication to those mines which are not yet drained4 ,in proportion to the successive acquisition to these subterranean works which are daily advancing1 will be the increased operations of the mines1 and consequently the increased prosperity of the mining interest1 which had most astonishingly fallen from the degree it had attained in former years4 ,in a short time1 similar effects will be seen in the three remaining mineral ridges of ,yauricocha1 ,caya1 and ,yanacancha1 productive of ores of a better quality than that of ,santa ,rosa1 which has nevertheless obtained the preference for the erection of the first engine upon it from its being more abundant in its peculiar produce1 and on account of the greater number of persons interested in this property2 as also its contributing immediately to relieve the necessitous1 by employing the workmen in the vicinity of the mines4 ,in my opinion1 no event so beneficial has occurred as the erection of the steam-engine1 since the discovery and addition of these dominions to the crown of ,castile4 ,from this time1 by the help of these machines1 immense and incalculable riches will accrue to the nation4 ,god preserve your ,excellency many years1 ,,jos ,,gonzales ,,de ,,prada4 ,the ,viceroy's ,answer4 ,,lima1 #eth ,august1 #ahaf4 ,your ,lordship's official despatch1 ,no4 #hih1 the #bgth of last month1 communicated to me the satisfactory detail of the complete results which you witnessed on the #bcrd and #bgth1 produced by the grand steam-engine placed over the mine of ,santa ,rosa1 one of those situated in the mountains of ,pasco1 for the purpose of draining the mine and extracting the ores4 ,i desire particularly to distinguish and patronize the chief agent and assistant1 ,don ,francisco ,uville2 the generous promoters of the undertaking1 ,don ,pedro ,abadia and ,don ,jos ,arismendi2 their agents and assistants1 ,don ,luis de ,landavere and ,don ,tomas ,gallegos2 and lastly1 ,mr4 ,bull1 and all those associated in this great work1 whom you recommend to my notice4 ,your ,lordship1 by having exerted yourself to facilitate1 by all the means which your zeal and authority could procure1 the happy consummation of so profitable an enterprise1 has added a new claim to the many preceding which you possessed1 to the high consideration of the king and the public4 ,,joaquin ,,de ,,la ,,pezuela1 ,viceroy of ,lima4 ,extract from the ',lima ,gazette' of the #beth of ,september1 #ahaf4 ,we have the satisfaction of communicating to the public the information that the company for draining the mines of ,pasco have just received accounts from their agents in that mineral territory2 and they promise for our next ,gazette a description of the state of the works for fixing the remaining three engines4--,,editor4 ,,cerro1 ,september #bjth1 #ahaf4 ',after having observed the progress of the machine at the ,santa ,rosa ,mine last ,saturday1 the #adth instant1 at #aj o'clock at night we began to act2 at #aa o'clock the pitmen went down to clear the shaft1 and have not since ceased working an instant4 ,the clearing of the mud and rubbish which had remained at the bottom of the shaft1 and clogged every moment the buckets and suckers of the engine1 lasted till ,wednesday2 but this being accomplished1 at #ab o'clock at noon they began to break through the level4 ,at half a yard below the shaft we found a lively coppery ore1 with its particles of silver4 ,this bronze-coloured ore indicates that the veins of ,yauricocha and ,san ,diego incline to the west1 or towards the ,santa ,rosa ,mine4 ,the mines in the vicinity of this pit are all dry4 ,some of them1 at the distance of #cjj yards1 in the ridge of ,santa ,rita1 have also felt its effects2 and even as far as the territory of ,caya1 behind our steam-works1 the waters have fallen in several mines4 ,don ,john ,vivas has begun to work in ,san ,diego ,mine4 ,they are also going next ,monday to begin working in several points of the ,santa ,rosa ,mine4 ,the pit is already #h yards in depth1 and we are proceeding with the greatest activity4 ,the workmen are relieved every two hours1 and as they go out they give up their tools to those who succeed them1 by which means not a minute is lost4 ,continuing thus1 in the course of a month we shall be at more than #bj yards depth1 and have many mines in full activity4 ,the winding engine raises a basket 7which is a load7 in two minutes2 the draining or steam-engine1 with two vibrations per minute1 keeps the surface always dry4 ,both work with the greatest ease1 certainty1 and regularity4 ',by dint of searching after a vein of coal1 we have at last found one near at hand1 of excellent quality and of great richness4 ,the pit we are now at work at is at the distance of a quarter of a league from ,rancas1 and at the same distance from ,vista ,alegre which the ,cerro is from these works4 ,we have likewise found a vein of plumbago1 which was an object of search1 on the supposition that it was coal4 ,this substance1 of which much is consumed1 mixed with grease1 to soften the friction of the piston1 c41 we have now here2 and thus the necessity of sending to ,lima1 or perhaps to ,europe1 for it is obviated4' ,within six months of the setting to work the pumping engine in ,santa ,rosa1 another pumping engine was at work at ,yanacancha ,mine4 ,the following extracts from the ',lima ,gazette' were published in the ,cornish papers by ,mr4 ,edmonds3-- ,from the ,government ,gazette of ,lima1 #abth ,feb41 #ahag4 ,we have had the pleasure of receiving a letter from ,pasco1 dated #fth instant1 containing the following account3-- ,the second engine established in the mine called ,yanacancha1 which is far superior in point of beauty1 convenience1 and size to that called ,santa ,rosa1 was set to work on ,friday last1 and notwithstanding the great quantity of water which filtered into this mine the engine with only half its power drained the mine completely in nine minutes4 ,this filtration did not happen in ,santa ,rosa1 on account of the quantity of hard copper ore on which the engine is situated4 ,by this successful operation1 the water in several mines has been lessened considerably1 amongst which in particular is that belonging to ,don ,juan ,vivas1 situate in the hill called ,chucarillo1 which at present affords ore of #djj marcos per caxon 7#ej cwt474 ,of this ore about #be lbs4 has been received in this city1 with a proof of #b lbs4 made in ,pasco1 showing not only the richness of the ore1 but its easy extraction and cleanness for the ready refinement of it4 ,and another proof has also been received from another mine1 situate in ,chucarillo1 belonging to the widow ,mier1 in company with ,don ,joachin ,aitola1 which yields #ajj marcos per caxon of #be cargas4 ,to this agreeable news we ought to add that at the arrival of the whaling ship ',asp1' bound from ,london1 having on board a large quantity of machinery for the ,royal ,mint1 and for the constructing of eight engines more1 equal to those in ,pasco1 with the advantage that they are of the last patent and more easy to be worked2 but what is of greater importance is the arrival of ,don ,ricardo ,trevithick1 an eminent professor of mechanics1 the same who directed in ,england the execution of the machinery now existing in ,pasco4 ,this professor can1 with the assistance of the workmen who accompany him1 construct as many engines as are necessary in ,peru1 without any need of sending to ,england for any part of these vast machines4 ,the excellent character of ,don ,r4 ,trevithick1 and his ardent desire for promoting the interests of ,peru1 recommend him in the highest degree to public estimation1 and make us hope that his arrival in this kingdom will form the epoch of its prosperity1 with the enjoyment of the riches enclosed in it1 which could not be enjoyed without this class of assistance1 or if the ,british ,government had not permitted the exportation from ,england1 which appeared doubtful to all those who knew how jealous that nation is in the exclusive possession of all superior inventions in arts or industry4 ,so far everything promised success4 ,two pumping engines had so reduced the water in two of the mines1 that the miners were at work1 and the people of ,lima believed that many more such engines would be usefully employed1 now that ,don ,ricardo ,trevithick was with them4 ,,dear ,,sir1 ,,lima1 ,february #aeth1 #ahag4 ,we arrived here last ,saturday in good health4 ,the 7our7 ,mint is at work1 and coined five millions last year1 and in their way of working does very well2 but ,i trust to make it coin thirty millions per year4 ,two engines are drawing water1 and two drawing ore1 at the mines1 but in an imperfect state4 ,if ,i had not arrived1 it must have all fallen to the ground1 both in their mining and in their engines4 ,i expect we shall go to the mines in about ten days1 from where ,i will write to you every particular4 ,there are still two engines to put up for lifting water1 and two for winding ore1 and those at work to be put to rights4 ,they are raising ores from one mine which is immensely rich1 and from what ,i can learn1 a much greater quantity will be got up1 when the whole are at work1 than these people have any idea of4 ,several other mines will also be set to work by engines that we shall make here4 ,we have been received with every mark of respect1 and both ,government and the public are in high spirits on account of our arrival1 from which they expect much good to result4 ,mr4 ,vivian died the #aith of ,may4 ,i believe that too much drink was the cause of it4 ,uville1 ,i think1 wished him gone1 and was in great hope that ,i should not arrive4 ,his conduct has thrown down his power very much1 which he never can again recover4 ,they all say that the whole concern shall be put entirely under my management1 and every obstacle shall be removed out of my road4 ,unless this is done1 ,i shall soon be with you in ,england4 ,i am very sorry that ,i did not embark with the first cargo1 which would have made a million difference to the company4 ,the first engine was put to work about three months since1 the other about two months2 but they are as much at a loss in their mining as in their engineering4 ,the ,mint is the property of our company1 and ,government pays us for coining1 which gives us an immense income2 the particulars of which1 and the shares in the mines1 ,i have not yet gone into4 ,i shall be short in this letter1 because ,i know but little as yet1 and that little ,i expect ,mr4 ,page will inform you4 ,a full account you shall have by the next ship1 which ,i expect will sail in three weeks4 ,this letter goes by a ,spanish ship that will sail this afternoon for ,cadiz4 ,my respects1 and good wishes to your family and to ,mr4 ,day1 and hope this will find you all as hearty as we are4 ,mr4 ,page would not depart this life under the line1 as he promised when at ,penzance2 but1 on the contrary1 has a nose as red as a cherry1 and his face very little short of it4 ,his health and spirits far exceed what they were in ,england4 ,i am glad to have such a companion4 ,with 444 think he will have no reason to repent4444 ,he will get a command at ,pasco 444 such as his ingenuity may find out1 when on the spot2 whether as a miner or an engineer ,i cannot say1 but time will show4 ,if you have not insured my life ,i would thank you to do it now1 if you can on reasonable terms4 ,i do not wish them to take the risk of the seas in the policy1 because the voyage here is over1 and on my return ,i hope ,i shall not want it1 therefore it must be for two years in the country4 ,i will get a certificate of my health1 if they wish it1 from the most respectable inhabitants1 and also from the ,vice-king1 if they wish it4 ,the policy may be drawn accordingly4 ,be so good as to write me often1 with all the news you can collect4 ,if you wish your dividends in this company to be applied to further advantage in any new mines ,i may engage in1 in preference to having it sent to ,england1 ,i will1 as the dividends are made1 do everything in my power to improve the talent4 ,on this subject ,i must have your answer before ,i can make any new arrangement under this head4 ,i will thank you to send a copy of ,mr4 ,page's letter to my wife2 ,i mean such parts of it as belong to the business2 there may be some things that ,i have forgotten to mention4 ,i remain1 ,sir1 ,your humble servant1 ,,richd4 ,,trevithick4 ,,mr4 ,,james ,,smith1 ,limekiln ,lane1 ,greenwich4 ,in the early part of #ahag four engines were at work in the mines1 two pumping water and two raising the ore2 while a fifth engine was coining in the ,mint at ,lima4 ,trevithick believed that he could much improve the engines and the mining1 and that it would be necessary and practicable to arrange for the construction of engines in ,lima2 for though death and dissension had caused difficulty1 the authorities were still prepared to give him full power4 ,a strange defect in his character is evidenced in this letter4 ,he wished his life to be insured for the benefit of his wife and family1 but never thought of paying the yearly insurance premium1 leaving it for his wife to pay1 whom he had left1 as far as he knew1 penniless in ,england4 ,on his sailing from ,penzance1 he told his wife that he had paid the house-rent for a year in advance1 mentioning the sum4 ,at the end of that time a demand was made on ,mrs4 ,trevithick for a year's rent1 being a larger sum than her husband had mentioned as the proper rent4 ,it turned out that ,trevithick had taken and paid for the house at six-monthly periods1 instead of yearly periods4 ,it was in the same street1 and but three or four houses from that occupied by the parents of the eminent ,sir ,humphry ,davy4 ,a person pressed him for payment of a bill4 ,trevithick said1 ,give me your bill1 and writing on the bottom of it ,received1 ,richard ,trevithick1 handed it back to the claimant with ,now1 will that do for you8 ,the payment of the life insurance obliged ,mrs4 ,trevithick to part with her personal property1 on which she had counted for support during her husband's absence4 ,this inability to see the necessity of methodical action1 when working with others1 and utter disregard for hoarded money1 caused him to be a somewhat unmanageable partner1 though his genius never allowed him to sink2 and in ,november1 #ahag1 he wrote a letter1 of which the following is an extract3-- ,illustration3 ,,market1 ,,jew ,,street1 ,,penzance4 ,w4 ,j4 ,welch4 ,there are also nunneries beyond number1 and in those places no male is ever suffered to put his foot4 ,through one of the most noted runs a watercourse1 which works the ,mint2 and ,mr4 ,abadia has repeatedly made all the interest he could to be admitted1 for the purpose of inspecting it1 but could never get a grant4 ,the ,mint belongs to our engine concern1 and now coins about five millions per year4 ,we have a contract from ,government for making all the coin1 both gold and silver1 which gives an immense profit2 and as there must now be coined six times as much as before1 ,i must build new water-99wheels to work the rolls which we took with us from ,england4 ,it was on this account that ,i wished to examine the watercourse for this purpose1 without the knowledge of ,mr4 ,abadia or anyone but ,mr4 ,page and the interpreter1 who always attends me4 ,i walked up and knocked1 in my blunt way1 at the nunnery court door1 without knowing there were any objections to admit men2 it was opened by a female slave1 to whom the interpreter told my name and business4 ,very shortly three old abbesses made their appearance1 who said ,i could not be admitted4 ,i told them ,i came from ,england1 for the purpose of making an addition to the ,mint1 and could not do it without measuring the watercourse2 upon which a council was held amongst them2 very soon we were ordered to walk in1 and all further nunnery nonsense was done away4 ,we were taken round the building and were shown their chapel and other places without reserve4 ,uville knew nothing about the practical part of the engines1 and ,bull very little1 therefore you may judge what a wretched state this great undertaking was in before my arrival2 no one put any confidence in it1 and believed it was all lost1 together with five hundred thousand dollars that had been expended on it4 ,the ,lord ,warden was sent from ,pasco to offer me protection and to welcome me to the mines4 ,they have a court over the mines and miners1 the same as the ,vice-,warden's ,court in ,england1 only much more respected and powerful4 ,the ,viceroy sent orders to the military at ,pasco to attend to my call1 and told me he would send whatever troops ,i wished with me4 ,the ,spanish ,government and the ,vice-king since my arrival are quite satisfied that the mines will now be fully carried into effect1 and will do everything in their power to assist me4 ,as soon as the news of our arrival had reached ,pasco1 the bells rang1 and they were all alive down to the lowest labouring miner1 and several of the most noted men of property have arrived here--#aej miles4 ,on this occasion the ,lord ,warden has proposed erecting my statue in silver4 ,on my arrival ,mr4 ,uville wrote me a letter from ,pasco1 expressing the great pleasure he had in hearing of my arrival1 and at the same time he wrote to ,mr4 ,abadia that he thought ,heaven had sent me to them for the good of the mines4 ,the water in the mines is from four to five strokes per minute4 ,tell the members of the ,geological ,society that ,mr4 ,abadia is making out a very good collection of specimens for them1 which will be sent by the first opportunity2 and soon after ,i arrive at ,pasco ,i will write them very fully4 ,after ,trevithick's death1 in #ahcc1 casts were taken from the head1 and busts presented to scientific societies were thankfully received1 with the single exception of his near neighbours at ,penzance1 who1 under the name of the ,royal ,geological ,society of ,cornwall1 refused it4 ,mr4 ,w4 ,j4 ,henwood1 who had frequently drawn the attention of ,cornishmen to ,trevithick's engines1 being about #ahgj ,president of the ,royal ,institution of ,cornwall1 presented to it a bust of ,trevithick1 which was admitted within its walls4 ,in #ahai ,mr4 ,r4 ,edmonds forwarded to the ',cornwall ,gazette' news from ,lima1 from which the following is extracted3-- ,we have much pleasure in stating that accounts have lately reached ,england from ,lima1 giving the satisfactory intelligence that our countryman and able engineer1 ,captain ,trevithick1 was in ,february last in good health1 and super-99intending the rich and extensive mines of ,pasco4 ,don ,francisco ,uville1 a ,spanish gentleman1 having1 with ,don ,pedro ,abadia and others1 formed a company to drain the mines of ,pasco1 unfortunately for ,captain ,trevithick1 ,f4 ,uville was anxious to impress his countrymen with an opinion that it was solely owing to him that steam-engines were first introduced into the silver mines of ,south ,america2 and notwithstanding the obligations he was under to ,captain ,trevithick1 he sought every opportunity1 soon after ,captain ,trevithick's arrival at ,pasco1 to oppose him1 in claiming to have the direction of the mines4 ,captain ,trevithick1 knowing but little of the country1 and disgusted with the treatment he received from ,uville and the party he had formed against him1 amongst whom was a gent who had lately arrived from ,england1 retired from the concern1 and proceeded on other important discoveries on his own account4 ,things remained in this state until ,august1 #ahah1 when ,uville met his death1 in consequence of the cold penetrating air of the ,cordilleras on coming out of the mines in a strong perspiration4 ,mr4 ,abadia and his friends were then under the necessity of soliciting the assistance of ,captain ,trevithick4 ,on condition of his having the sole direction of the mines1 he was prevailed upon to accept the situation which had been first most faithfully agreed he should have had2 and when the accounts last left ,lima in ,february1 ,captain ,trevithick had been five months at the mines as the chief superintendent4 ,the mines are represented as being in the most prosperous state1 and likely to realize the sanguine expectations of the share-99holders4 ,mr4 ,bull1 an engineer from ,chacewater1 who left ,england with ,uville1 died at ,pasco about ten months since4 ,when this was written1 ,trevithick had been two years in the country1 and found the immense difficulties of the undertaking increased by jealousies and jobberies4 ,mr4 ,uville was no more1 neither were ,vivian or ,bull2 but one man remained alive out of the four who had sailed from ,england with the first cargo of machinery4 ,in ,august1 #ahah1 ,mr4 ,abadia1 who from the first was a leading authority1 requested ,trevithick to take upon himself the sole management of the mines1 where he continued until ,april1 #ahai1 as shown by the following extract from ,captain ,hodge's journal1 supplied by my friend ,mr4 ,charles ,hodge3-- ,the first time they met was at ,lima1 on the #bfth ,april1 #ahai1 at ,dr4 ,thorne's2 your father had just come down from the ,cerro de ,pasco mines4 ,on the #hth ,may following1 ,i find my father witnessed the hanging of three men for killing two of your father's men1 named ,judson and ,watson4 ,mr4 ,w4 ,b4 ,stevenson says3#abh-- ,footnote #abh3 ,see ',historical and ,descriptive ,narrative of ,twenty ,years' ,residence in ,south ,america1' by ,w4 ,b4 ,stevenson1 published #ahdb4 ,the ,mint was established in ,lima1 in #aefe4 ,the machinery was formerly worked by mules1 eighty being daily employed till the year #ahag1 when ,don ,pedro ,abadia1 being the contractor for the coinage1 ,mr4 ,trevithick directed the erection of a water-wheel1 which caused a great saving of expense4 ,in the year #ahag two ,englishmen1 sent from ,pasco by ,mr4 ,trevithick 7who afterwards followed with the intention of working some of the silver mines in ,conchucos71 were murdered by the guides at a place called ,puloseco4 ,this horrid act was perpetrated by crushing their heads with two large stones1 as they lay asleep on the ground4 ,the murderers were men who had come with them from ,pasco4 ,i have heard ,mr4 ,trevithick say1 that on shaking hands with the men who work in those quicksilver evaporating rooms1 drops of quicksilver show themselves at the fingers' ends1 and that the workmen wearing shoes take them off before leaving the work1 to pour out any quicksilver that had oozed through the pores of the skin1 which had been respired in the floating state of vapour4 ,the men so employed fell a sacrifice in twelve or eighteen months4 ,trevithick's experience in applying the force of running streams was turned to good account in giving an economical helpmate to the steam-engine then at work in the ,mint4 ,miers says3#abi-- ,footnote #abi3 ,see ,miers' ',travels in ,chili and ,la ,plata1' published #ahbf4 ,another instance occurs in the unfortunately ruinous result and lamentable ill-treatment of the persons engaged in the attempt to introduce ,european improvements and ,british machinery into the great silver-mining district of ,pasco 7,chili71 in which was engaged one of our most celebrated engineers1 a most able mechanic1 to whom the grand improvements in our ,cornish mines are chiefly indebted--,i mean ,mr4 ,richard ,trevithick4 ,trevithick was induced to furnish the machinery at an expense of #cjjjl4 sterling1 upon condition of being admitted a partner in the amount of #ab1jjj dollars in the joint stock of the company1 and entitled to a share corresponding to the capital employed4 ,this share was calculated at a fifth4 ,trevithick1 before he embarked for ,peru1 divided his interest in the concern into #cbj shares1 each representing #ch dollars1 and these were sold in the market for #abel4 sterling each2 some few were sold for #ajjl4 cash4 ,the success of the engines gave to some of the persons interested much confidence1 who conceived they could now do without the management of the ingenious ,trevithick4 ,every possible obstacle was therefore thrown in his way by those who1 from motives of jealousy1 wished to get rid of him4 ,the persons to whom ,trevithick's and other shares had been sold in ,london1 sent out to ,lima an agent1 whose duty it was to look after their interests in the concern2 but as it was found a much larger sum would be necessary for carrying the enterprise into effect than had been calculated1 a collision of interests took place2 complaints were made on all sides as to the delays and expenses which those who did not comprehend the almost insurmountable difficulties of the undertaking attributed to mismanagement and carelessness4 ,the greatest share of opprobrium fell unjustly upon ,trevithick1 who1 being a man of great inventive genius and restless activity1 was at length completely disgusted1 and retired from the undertaking4 ,he left ,pasco1 although ,abadia offered him #hjjj dollars per annum1 together with all his expenses1 if he would continue to superintend the works2 on no conditions would he consent to contend with the jealousies and ill-treatment of the persons with whom he had to deal4 ,he soon after entered into speculations with some of the miners at ,conchucos1 for whom he constructed grinding mills and furnaces1 with the view to substitute the process of smelting for that of amalgamation in silver ores1 in which vain pursuit he became a considerable loser4 ,,my ,,dear ,,sir1 ,,bodmin1 ,november #crd1 #ahfi4 ,forty-seven years are now passed since ,i had the great pleasure of meeting your father in ,peru1 and ,i have a vivid remembrance of the gratification afforded to my messmates when he came to dine with us on board ,h4,m4,s4 ',aurora1' then lying in ,callao4 ,i was then a lieutenant of that beautiful frigate1 and was introduced to your father by ,mr4 ,hodge1 of ,st4 ,erth1 with whom ,i had become acquainted in ,chili4 ,i remember your father delighting us all on board the ',aurora' by his striking description of the steam-engine1 and his calculation of the 'horse-power' of the mighty wings of the condor in his perpendicular ascent to the summit of the ,andes4 ,your father's strong ,cornish dialect seemed to give an additional charm to his very interesting conversation1 and my messmates were most anxious to see him on board again1 but he left shortly after for the ,sierra4 ,the ,pasco-,peruvian mines were those which your father was engaged to superintend before he left ,england1 and he had actually managed1 by incredible labour1 to transport one or two steam-engines from the coast to the mines1 when the war of independence broke out1 and the patriots threw most of the machinery down the shafts4 ,this fearful war was a deathblow to your father's sanguine hopes of making a rapid fortune4 ,about a year after this terrible disappointment 7,i think in #ahbb71 the ',san ,martin1' an old ,russian fir frigate1 purchased by the ,chilian ,government1 sank at her anchors in ,chorillos ,bay1 ten miles south of ,callao1 and your father entered into an engagement with the ,government in ,lima to recover a large number of brass cannon1 provided that all the prize tin and copper on board which might be got up should belong to him4 ,this was a very successful speculation1 and in a few weeks your father realized about #bejjl4 ,i remember visiting the spot with your father whilst the operations were carried on1 and being astonished at the rude diving bell by which so much property was recovered from the wreck1 and at the indomitable energy displayed by him4 ,it was ,mr4 ,hodge1 and not ,i1 who then urged in the strongest manner that at least #bjjjl4 should be immediately remitted to your mother4 ,instead of this1 he embarked the money in some ,utopian scheme for pearl fishing at ,panama1 and lost all6 ,i had the honour of dining with ,lord ,dundonald on board the crazy frigate ',esmeralda1' which carried his flag in ,callao ,bay1 but ,i never heard of the gallant conduct of your father in swimming off to his ship and advising him of an intended assassination4 ,i fancy that this must have occurred before ,i came on the station1 probably in #ahbj1 or #ahba4 ,believe me1 ,my dear ,sir1 ,very sincerely yours1 ,,james ,,liddell4 ,trevithick's floating caissons for the sunken ship of ,margate ,bay in #ahajacj were similarly applied in #ahba in the ,bay of ,callao4 ,in ,lima he became acquainted with ,lord ,dundonald1 whom he warned of a plot on his life1 discovered in his friendly intimacy at the residence of ,president ,bolivar4 ,those two remarkable ,englishmen were alike in their daring inventiveness1 and not unlike in face and person4 ,footnote #acj3 ,in #ahcd the writer was employed at a marine engine works in ,london1 and made working drawings for a scheme of ,lord ,dundonald's1 who expressed great pleasure in meeting the son of his old friend4 ,we have traced ,trevithick's steps from his landing at ,lima in #ahag to the destruction of the mine machinery by the civil wars1 and his departure from there about #ahbb4 ,but one link in the chain has been nearly lost4 ,during some portion of those five years he visited ,chili1 and set to work mines which are still producing large and profitable quantities of copper4 ,the late ,mr4 ,waters1 an eminent ,cornish miner1 who for many years managed some of these mines in the neighbourhood of ,valparaiso1 said that ,trevithick's name was better known to the miners there than to the miners in ,cornwall4 ,this statement was made in the ,dolcoath account-house at a public meeting1 the speaker and the writer being both on the committee of management4 ,simon ,whitbarn1 of ,st4 ,day1 informed the writer that at ,copiapo and at ,coquimbo he had seen large heaps of copper ore1 apparently unclaimed1 which the people said had been raised by ,don ,ricardo ,trevithick4 ,about #ahcj a miner1 returned from ,south ,america1 made a claim for wages for watching mineral left behind by ,mr4 ,trevithick4 ,to further illustrate this history1 we have a report written by himself3-- ,memoranda regarding the ,copper and ,silver ,mine of 99 99 99 994 ,in #ahad an arrangement was made between the miners of ,peru and myself for furnishing them with nine steam-engines and a mint1 to be executed in ,england and erected in the mines of ,pasco2 and in ,october1 #ahaf1 ,i sailed from ,england for that country1 for the express purpose of taking the management of those mines and erecting the machinery1 being myself a large proprietor of the same4 ,the ,government of ,peru was at that time subject to old ,spain1 under the immediate superintendence of a ,viceroy4 ,the machinery having been erected1 and its sufficiency for the intended purpose of draining the mines having been proved to the satisfaction of all parties1 there was granted to me a special passport by the ,viceroy1 for the purpose of travelling through the country to inspect the general mining system1 and to make the native miners acquainted with the ,english modes of working4 ,in return for which ,government conceded to me the privilege of taking possession for my own benefit and account of such mining spots as were not previously engaged4 ,in this way ,i travelled through many of the mining districts1 and although ,i met with several unoccupied spots which would have paid well for working1 yet1 being a considerable distance inland1 and requiring more capital to do them justice than ,i could then advance1 ,i abandoned for the time all ideas of undertaking them4 ,to this1 indeed1 there was but one exception1 and that was a copper and silver mine1 the ores of which are uniformly united1 in the province of ,caxatambo4 ,when the patriots arrived in ,peru1 the mine was deserted by all the labourers1 in order to avoid being forced into the army4 ,in this state it remained for a considerable time2 but on the ,spaniards retreating into the interior1 ,i recommenced working2 and to secure my right to this mine under the new ,government ,i at the same time transmitted a memorial and petition to the established authorities1 accompanied by a plan and description of the mine1 the result of which was the formal grant1 as exhibited in the ,spanish document now in your possession4 ,it was not my good fortune to be allowed to follow up my plans1 which almost warranted a certainty of success4 ,i had scarcely commenced a second time when the ,spaniards returned1 and everyone again was obliged to fly4 ,the country1 as is well known1 continued for a long time in a most distracted state1 and ,i was ultimately compelled to quit that part of ,peru1 robbed of all my money1 leaving everything behind me1 miners' tools and about #ejjjl4 worth of ores on the spot ready to be carried to the shipping port4 ,numerous as my misfortunes had been in ,peru1 and heavy as my disappointments1 ,i felt none so sensibly as this1 because it was an enterprise entirely of my own creation1 and so open to view that ,i was enabled to calculate at a certainty the immense value contained within the external circle where the copper vein made its appearance in the cap of the mountain1 and to be obtained without risk or capital4 ,however1 revolution followed revolution1 and the war appeared to me to be interminable4 ,even ,bolivar's arrival at ,lima made it still worse1 for he forced me into the army1 with my property1 which is not paid to this day1 to the amount of #bj1jjj2 and at his urgent solicitations1 disgusted as ,i was with what ,i had seen and suffered in ,peru1 ,i determined on quitting it for a time at least1 and on visiting ,colombia4 ,being at ,guayaquil ,i first heard the name of ,costa ,rica and its recently-discovered mines1 and having no doubt of the authenticity of my information1 ,i immediately proceeded thither instead of going to ,bogota to carry ,bolivar's orders into execution1 not having been paid4 ,this short digression you will excuse1 as it points to the causes of my separation from a property of so much value1 as ,i consider the mine of 99 99 99 99 994 ,thirty years ago the neighbourhood of 99 99 99 99 was famous for its silver mines4 ,at the foot of the copper hill1 on a fine stream1 are two sets of works on a most extensive scale1 which were carried on on account of the ,spanish ,government4 ,the silver was found in lead veins1 which are very large and numerous all around4 ,the soil is very rich1 and the climate as good as any in the world1 wheat and ,indian corn both growing round the mountain4 ,provisions and wages are low1 the latter #as4 per day1 and there are about #bj1jjj inhabitants within three miles4 ,wood for smelting and other purposes is abundant on the spot4 99 99 99 99 is 99 99 leagues from ,lima2 the port of 99 99 99 99 where the ores are to be shipped1 is #cg leagues north from ,lima2 and 99 99 99 99 copper mine 99 99 leagues back in the country east from this port1 a good road for mules and plenty of them4 ,the miners contracted with me to break the ores and deliver them at the surface for #dl4 per ton1 which was double what ,i ought to have paid them2 the farmers likewise contracted to carry the ores to the port at the same rate1 which comes to sixpence a league for each mule cargo4 ,but even at present wheel-carriages might travel over a large proportion of the road1 and a small outlay would make it a carriage-road the whole distance1 and then the expense of carriage would be diminished more than one-half4 ,taking it1 however1 at what it cost me1 the whole expense on the ores delivered on board would not amount to #il4 a ton1 and as ,i conceive the freight to ,england would not exceed #dl4 a ton1 the total cost would be #acl41 but say #ael4 a ton4 ,its value in ,england would be above #hjl4 a ton4 ,at the time ,i worked ,i intended to have sent #cjj tons of ore to ,england1 for in the then disturbed state of the country it would not have been prudent to risk myself on smelting works4 ,i think it will ultimately be found preferable to smelt on the spot1 but the course ,i should recommend in the meantime would be to send out two practical miners to direct and superintend the natives1 who ought to be employed by contract to break and raise the ores and deliver them on board4 ,in that case no erections whatever would be wanted2 nothing but about #gjl4 worth of labourers' tools4 ,i remain1 ,sir1 ,your very humble servant1 7,signed7 ,,richard ,,trevithick4 ,the foregoing undated report was written after his return to ,england from ,south ,america4 ,the ,viceroy granted him a special passport through the country1 that he might give general instructions to the workers of mines1 with the right to claim any mineral spot for his own working not under grant to others4 ,he often spoke of his discovery and working of the great vein of copper ore in ,caxatambo1 estimated to contain copper worth twelve millions sterling1 the working of which was prevented by the frequent revolutions and unsettled government of the country2 and of residing for months with ,bolivar1 at that time the ,republican ,governor of ,peru4 ,bolivar's cavalry were short of fire-arms4 ,trevithick invented and made a carbine with a short barrel of large bore1 having a hollow frame-work stock4 ,the whole was cast of brass1 stock and barrel in one piece1 with the necessary recess for the lock2 the bullet was a flat piece of lead1 cut into four quarters1 held in their places in a cartridge until fired1 when they spread1 inflicting jagged wounds4 ,he was obliged to serve in the army1 and to prove the efficiency of his own gun4 ,he was never a good shot1 nor particularly fond of shooting2 and1 after a long time1 ,bolivar allowed him to return to his engineering and mining4 ,scarcely had he got to work again when the ,royal ,spanish troops1 getting the best of it1 overran the mines1 and drove ,trevithick away penniless1 leaving #ejjjl4 worth of ore behind him ready for sale4 ,the #cjj tons of ore1 valued at #bd1jjjl41 never reached ,england2 and the writer1 who was to have returned to ,peru in the ship that had been engaged to convey it1 lost the chance of being a youthful traveller in foreign lands4 ,trevithick left ,lima about #ahba or #ahbb1 for ,bogota1 in ,colombia1 on a special mission for ,bolivar4 ,on his way1 putting in at ,guayaquil1 he heard of rich mines in ,costa ,rica1 and thinking they would pay better than ,bolivar's promises1 he threw up his engagement and made for the new venture4 ,it was probably at ,guayaquil that he met ,mr4 ,gerard1 a ,scotchman of good family and education1 then sailing on the ,pacific coast as a speculator4 ,since ,trevithick left the mines of ,cerro de ,pasco1 more than one ,english adventurer has attempted to work them4 ,at the present time they are in the hands of a large company1 and are thus spoken of in the ',cornish ,telegraph' of ,may #aj1 #ahga3-- ,cerro de ,pasco and its ,silver ,mines4 ,this place1 in the ,republic of ,peru1 is situated on the top of the ,andes1 on the eastern side of the ,western ,cordillera4 ,it stands about #ae1jjj feet above the sea level1 and is said to be one of the highest1 if not the highest1 inhabited place of importance in the whole world4 ,from ,callao to here is a distance of #afj miles1 but1 in consequence of the rapid ascent in such a comparatively short distance1 it is considered a quick journey if mules make it in six days2 it more frequently takes them a week1 and at times1 during the season of snow and rain1 the pampas1 which are the table-lands of these mountains1 are impassable for several days together4 ,the town of ,cerro de ,pasco1 which at present numbers #aj1jjj souls1 is of no small importance1 considering its great altitude and inconvenient distance from the coast1 but it lacks order and design in every part4 ,the streets are crooked and uneven2 and the houses are stuck about anywhere and everywhere1 with the greatest display of uneducated taste that ,i have ever before witnessed2 moreover1 it would be difficult to find another such place so equally dirty4 ,it rains and snows on these heights with not much cessation for about six months in the year1 and in what is termed the dry season there are also frequent falls of snow4 ,furthermore1 water boils at #ahj ,fahr4 instead of at #bab1 as with you2 consequently it requires six minutes to cook an egg4 ,the majority of the inhabitants are a low type of ,indians1 who are small in stature and mind1 but are large in cunning1 and have exceedingly plain features--not possessing the slightest trace of the noble features and bold simplicity of the ,indians of the ,north4 ,any person acquainted with minerals and mining coming up to ,cerro de ,pasco would fancy that the whole town was built on the back of one huge lode2 go wherever one may1 through the streets1 or on the outskirts of the town1 and even up to the slopes of the hill surrounding it1 he finds it to be all lodestuff everywhere2 its composition is what we ,cornish miners generally term an iron gossan4 ,the greater portion of this mineral spot is parcelled out into setts or grants1 which consist of pieces of ground #fj yards in length by #cj in width1 giving to the place no less than #ffd mines4 ,at present there are no more than seventy-eight of them at work1 and only sixty-three of which are producing ore1 and the united returns amount to #b1jjj1jjj oz4 of silver per annum4 ,owners or companies have roads leading down to their mines1 formed of steps cut out in the rock1 dipping at angles varying from #cj to #ej4 ,when you have descended to the depth of the mines1 the levels or holes leading to many of them are so small that one has to drag himself along snake fashion until he reaches the main excavation4 ,the miners break down the silver ore with pointed bars of iron1 and then shovel it into bags made of hide with the shoulder-bone of some animal2 after which the stuff is carried to surface on men's and boys' backs4 ,when all the mineral has been extracted there remains an immense excavation1 and in consequence of the roof not being properly supported with timber1 one risks his life in entering it4 ,heavy falls of rock frequently occur1 and by which means a vast number of persons are annually killed4 ,one day in the last century1 at the mines of ',matagente' 7which word means killed people71 which are situated in the rising ground on the northern side of the town1 while a great number of men and boys were at work1 the roof of one of these immense chambers1 consisting of many thousands of tons1 fell in without giving the least warning1 and 'in the twinkling of an eye' the souls of #cjj ,peruvian miners rushed into the presence of their ,redeemer4 ,their bodies have never been exhumed1 and their shattered bones1 still remaining1 will bear evidence of the catastrophe to future explorers4 ,an adit has been driven through the district1 beginning at the ,lake of ,quiulacocha on the south-west1 and terminating at the mines of ,ganacaucha on the north4 ,the entire length of the adit1 including its branches1 is about #c miles1 and its average depth from surface #ej fathoms4 ,three perpendicular shafts1 situated at about #fjj yards apart1 have also been sunk from surface to a short distance below the adit4 ,the whole of the machinery for the mines in question1 which is being made and dispatched by ,messrs4 ,harvey and ,co41 of ,hayle1 ,cornwall1 consists of four steam pumping engines1 six boilers1 four iron main beams1 four balance ditto1 and also a sufficient quantity of #bd-;inch pit-work for both shafts4 ,no single piece of all this cumbrous machinery must weigh more than #cjj lbs41 in consequence of its having to be transported on the backs of mules from the coast to this mountainous region4 ,although the main distance is no more than #afj miles1 these beasts with their burdens have to climb an altitude of #ae1jjj feet before they reach their destination4 ,moreover1 the passes in ascending the ,andes and ,cordillera can only be correctly imagined by experienced travellers4 ,some of the defiles are not much wider than a sheep-path1 and with a thousand feet below you a roaring cataract1 and thousands of feet above you snow-capped overhanging mountains1 looking so dreadful that the awe-struck stranger in the pass fears that the next peal of thunder will cause them to topple4 ,illustration3 ,,mule ,,track ,,from ,,lima ,,to ,,cerro ,,de ,,pasco4 ,w4 ,j4 ,welch4 ,i observe in a paper which is now before me1 entitled ',the ,introduction of the ,steam-,engine in the ,peruvian ,mines1 by ,richard ,trevithick1 in #ahaf1' that when ,captain ,trevithick arrived at ,lima on board the ship ',asp1' with sundry small engines for the draining of the mines of ,cerro de ,pasco1 he was immediately presented to the ,marquis de ,concordia1 then ,viceroy of ,peru1 was most graciously received by the most flattering attention of the inhabitants1 and subsequently the ,viceroy ordered the ,lord ,warden of the mines to escort the great man with a guard of honour to the mining district4 ,in contrasting the two epochs1 that of ,trevithick in #ahaf1 with this of ,wyman and ,harrison in #ahga1 one is led to exclaim that there were gentlemen in ,peru in #ahaf1 and they gave unto ,csar that which belonged to ,csar4#aca ,footnote #aca3 ,in ',mining ,journal1' ,w4 ,r4 ,rutter4 ,the same newspaper1 on the #ith ,november1 #ahgj1 stated3-- ,the ',bride' sailed from ,hayle on ,thursday with a portion of the machinery made by ,messrs4 ,harvey and ,co41 of ,hayle1 destined for ,cerro de ,pasco1 in ,peru4 ,the work comprises four #cg-;inch cylinder pumping engines2 no part to weigh more than #cjj lbs4 ,to enable the parts to be reduced in weight1 each steam-cylinder was made of thirty-seven different pieces4 ,the mechanics of ,trevithick's time could not make a steam-cylinder in parts2 therefore his difficulties in designing and conveying the machinery were ten times greater than they would be in the present day1 and necessitated the extreme simplicity of his engines4 ,his residence with the ,peruvians from #ahaf to #ahbb taught them the use of high-pressure steam-engines in their mines2 and indirectly heralded the advent of the steam-horse1 now as familiar to them as to the residents in many ,english towns4 ,,chapter ,,xxiii4 ,,costa ,,rica4 ,,my ,,dear ,,sir1 ,in the month of ,june1 #ahbb1 ,i disembarked in the port of ,punta de ,arenas1 in the ,gulf of ,nicoya1 the only one corresponding to that province at present in use on the ,pacific side4 ,my object was to dispose of a cargo of cotton which ,i had brought from ,realejo1 and to purchase sugar in return4 ,circumstances1 not necessary to mention1 and the loss of the small vessel with which ,i was trading on the coast1 caused me to remain in ,costa ,rica4 ,its name implies a very early conviction of its natural opulence2 it is certain that gold and silver abounded among the ,indians at the period of its conquest by the ,spaniards4 ,it was at one time a favoured and flourishing agricultural colony1 but from various causes sank into neglect4 ,such was the apathy1 both of the ,government and of individuals1 that the very existence of the precious metals in the country had been almost entirely forgotten4 ,in the end of #ahba1 a poor man1 ,nicolas ,castro by name1 opened the first gold mine known in ,costa ,rica since the conquest1 and his success soon induced others to try their fortunes2 with fortunate results1 in a few months a mining district sprang into being4 ,a gentleman of the name of ,alverado constructed at a very considerable expense what is called an ,ingenio1 consisting of various edifices for depositing the ore1 machinery driven by water for grinding it and afterwards blending it with quicksilver for amalgamation4 ,illustration3 ,,plate #ad4 ,london3 ,e4 ,f4 ,n4 ,spon1 #dh1 ,charing ,cross4 ,kell4 ,bros ,lith4 ,london4 ,,trevithick',s ,,route ,,across ,,the ,,isthmus ,,of ,,costa-,,rica4 ,when ,i landed in ,june1 #ahbb1 only five or six mines had been discovered1 but in ,january #ahbc1 when ,i left the country1 ,i cannot pretend to enumerate those in a state of progress and of promise4 ,it is not only in the mining part of the business that the want of skill is prejudicial to the result4 ,it is imperfectly ground1 for instance1 and consequently cannot be brought into that intimate contact with the quicksilver which is necessary to perfect amalgamation4 ,the machine for grinding is very simple3 a large flat stone1 like a mill-stone1 is made to revolve upon its fellow by an ox or mule power4 ,the poorest people reduce it to powder by manual labour1 in the same way as they grind corn preparatory to baking it into cakes4 ,alverado's machine promised to be a great acquisition4 ,the grinding was facilitated by a little water2 when the ore is judged to be sufficiently well ground1 a portion of quicksilver is thrown in by guess1 and the motion of the machine continued until the union of the metals is supposed to be complete2 the whole is then removed into large wide-mouthed conical-shaped wooden vessels4 ,in these receptacles it undergoes repeated washings1 by stirring occasionally round1 and afterwards communicating to the vessel a swinging or half-rotary motion1 by which a quantity of the water1 having the earthy particles suspended1 is driven over the edges2 the amalgamated mass naturally sinks to the bottom1 and at last remains tolerably clean4 ,the next step is the recovery of the quicksilver by distillation1 after which the gold is melted in a crucible and run into ingots4 ,the coasts are hot1 and from the luxuriant vegetation that everywhere abounds1 emit1 as in all situations of the kind1 febrile miasma in abundance when acted on by heat and moisture2 but black vomit is unknown1 and all the fever cases ,i have seen have been of the remitting and intermitting1 free from character of malignancy4 ,as the ground begins immediately to spring from the coast1 and does so indeed very rapidly1 a few miles takes us beyond the region of even these slight fevers1 and as we continue ascending to the central table-land1 a climate is encountered that may vie with any in the world for benignancy and beauty4 ,we there meet with the fruits of the torrid zone1 and near them the apple and the peach of ,europe4 ,the orange tree is in bearing the whole year4 ,as in all situations within the tropics1 it has a proper rainy season1 but it is less inconvenient and disagreeable than might be expected1 for it seldom rains two days in succession1 and when it does1 is invariably succeeded by an interval of fine weather2 for the most part every day presents a few dry hours4 ,the mines are situated on the ridges of the ,cordillera1 which without presenting snow-covered peaks1 attain1 nevertheless1 considerable elevation4 ,the clouds1 constantly attracted by those high summits1 render the rainy season more severe in the mining district than in the plains4 ,the greatest inconvenience was from the snakes1 which in those solitary jungles1 now first invaded by man1 are very numerous and many of them venomous4 ,provisions are cheap and excellent4 ,in short1 there is but one fault ,i find with the country1 and it is a great one1 ,i mean the frequency of earthquakes4 ,j4 ,m4 ,,gerard4 ,,mem4 ,,in ,,mr4 ,,gerard',s ,,writing4 ,illustrations of the ,map4 ,though the plans and sections explain themselves1 a few observations will not be misplaced4 ,the deep adit for the ,coralillo would be #fjj yards1 that for ,quebrada-honda #djj yards1 and besides serving as drains would form admirable roads for conveying the ores into the vale where the stamps must be erected4 ,the veins would be worked upward from the adits1 and thus no expense would be incurred for ages to come in lifting either water1 ore1 or rubbish to the surface4 ,padre ,arias ,mine is an exception1 requiring a powerful water-wheel1 or an hydraulic pressure-engine1 for which there is a fine fall of water of #ace feet4 ,the mines in ,quebrada-honda are those in which an interest has been procured4 ,captain ,trevithick has an interest in the mine of ,coralillo2 the great watercourse is also his4 ,it will be seen by the plan that there are #ge fathoms fall to the point where his present mill is situated1 and other #ge fathoms to the junction of the rivers of ,quebrada-honda and ,machuca4 ,the whole length does not amount to two miles1 within which it is estimated that sufficient power may be commanded to stamp #ejj1jjj of quintals annually4 ,to bring it up to that pitch1 the waters of ,machuca must be brought to join those of ,quebrada-honda at ,trevithick's mill1 and then #dj tons of water per minute could be delivered in the dry season4 ,extracts from a report by ,trevithick and ,gerard in #ahbg3-- ,this map consists of several distinct parts4 ,the middle part shows the mining district1 the present dimensions of which are small1 the length being hardly four miles1 breadth from two to three1 and the superficial extent from eight to ten miles4 ,the upper part of the plan is a section of the north ridge1 called ,quebrada-honda1 and shows the line of the proposed adits4 ,the lower part in like manner exhibits the south ridge1 called ,coralillo4 ,the map further shows the inclination or gradual fall of the ground along the valley1 and of the streams by which the mills are driven4 ,the canal is likewise shown #ejjj yards in length1 by which the rivers of ,machuca would be brought to join that of ,quebrada-honda4 ,castro's mine is situated on the southern ridge1 and was the first mine worked to any extent4 ,there the veins are very large2 in fact1 from the manner in which a number of horizontal veins are seen falling into the perpendicular or master vein1 the great body of the mountain would appear to consist of lodes4 ,this mass of ore is in general rich4 ,it has been worked open to the surface1 somewhat like a quarry1 so that it is not difficult to calculate in cubic feet the quantity that has been excavated4 ,the mine is supposed to have yielded in the course of the last six years gold to the value of #dj1jjjl41 and by measuring the excavations it would appear that this amounts to1 on an average1 one ounce of fine gold to every ten or twelve quintals of ore4 ,in #ahba the existence of silver was only imagined4 ,in #ahbc it was fully ascertained4 ,ever since #ahbd it has constituted a small but constant portion of the produce of ,quebrada-honda1 and in #ahbg it was decidedly evinced in ,coralillo4 ,the discovery of gold in ,coralillo led them to work in ,quebrada-honda1 where they found both gold and silver1 and the discovery of silver in ,quebrada-honda1 by strengthening the expectation of it in ,coralillo1 led in its turn to the discovery of silver there4 ,in ,quebrada-honda they only work on the ground in the immediate vicinity of the stream1 and that in the most imperfect manner2 but great light has been thrown on the value of the ores on this spot and in the district generally by the progress made in working what is called ,padre ,arias ,mine1 which takes its name from an ecclesiastic who first worked it4 ,this mine is situated in low ground near the verge of the stream1 and was at first only worked for gold4 ,there were soon1 however1 indications of silver1 which increased progressively in sinking1 till at the depth of only #aj yards the influx of water exceeded the means of draining1 and the works under water-level were necessarily abandoned1 at a time when ores were yielding upwards of #bjj oz4 of silver to the ton1 a striking proof of the tendency of silver ore to improve in this district as the depth increases4 ,mr4 ,richard ,trevithick1 that eminent ,cornish miner and engineer1 so well known for his inventions1 and particularly for the high-pressure steam-engine and the drainage of the ,pasco ,mines in ,peru1 when unfortunately civil war burst out in ,peru1 and the ,royalists1 considering those engines as the main instrument for supplying money to the ,independents1 rendered them useless by destroying or carrying off some of the most important pieces4 ,mr4 ,trevithick having heard favourable reports of the mining district we are now describing1 soon after repaired thither1 and was so fully impressed with its value and importance that he made an extensive contract for different properties1 and resided in the country for four years4 ,he is now in ,england ready to give explicit answers to any inquiries that may be made as to the mineral wealth of ,costa ,rica1 and the extraordinary facilities afforded by its position and natural advantages4 ,an estimate has been made for establishing a complete mining concern in ,costa ,rica1 with houses1 iron railroads1 stamping mills1 c41 so as to raise1 stamp1 and bring into refined gold the produce contained in #bej1jjj tons of ore per year4 ,the result of six years' experience shows that the following list of machinery and tools with a few miles of railroad would be sufficient4 ,the communication with the mines being satisfactorily established by the route of the port of ,san ,juan de ,nicaragua and the river ,serapique1 the materials would be sent by the ,atlantic at very much less cost than by around ,cape ,horn4 ,it is situated within #ad leagues of the ,pacific ,ocean and #cj leagues of the ,atlantic1 in a mountainous district intersected by deep valleys or ravines4 ,the mountains are covered with wood fit for fuel1 mining1 architecture1 and machinery4 ,there is a population of #ej1jjj inhabitants within one day's journey of the mines4 ,the climate is perfectly salubrious1 provisions of all kinds remarkably cheap1 labourers' wages from four to five dollars per month4 ,the mines secured are freehold property1 and with one exception are unencumbered by tribute or native partners4 ,the attention of ,government and of individuals has recently been directed to the discovery of a road from the interior to the river ,serapique1 which1 rising in the high lands of ,costa ,rica1 pursues a northerly course and joins the ,san ,juan about #aj leagues above the harbour of that name1 being itself navigable for about #ab leagues above the junction4 ,the opening of this road is a matter of much importance to ,costa ,rica in a general point of view2 the port of ,matina being always bad and impracticable during the prevalence of northerly winds2 that of ,san ,juan being1 on the contrary1 capacious1 easy of access1 and at all times perfectly secure4 ,the distance is much the same as by the way of ,matina4 ,several expeditions have been undertaken with a view of exploring an eligible road to the highest navigable point of ,serapique1 and although as yet none fit for mules has been discovered1 the results of the experiments justify the expectation of success4 ,individual enterprise is active in the attempt1 and ,government has wisely offered a reward to successful speculators4 ,captain ,trevithick and ,mr4 ,gerard1 with a particular view to the enterprise now under consideration1 and after considerable risk and labour1 succeeded in laying down the navigable head of the ,serapique and in throwing such light on the intervening tract as will be of great assistance to future adventurers4 ,they ultimately constructed a canoe in which they sailed down to the port of ,san ,juan4 ,plate ,,xiv4 shows ,trevithick's route across ,costa ,rica4 ,a memorandum in ,trevithick's writing1 apparently a diary1 says3-- ,from where we returned our mules to the place where we commenced to make our rafts and boat was eleven days' journey1 a distance of #ej or #fj miles4 ,the first and second days after parting with the mules we passed some soft ground1 with three or four rivulets of water in narrow vales1 about #aj miles on the side of the decline of the high ridge on our left4 ,it could easily be made passable for mules1 as the bad places where they could not travel did not exceed two or three miles2 and had we kept a little more to the left above the soft ground1 probably they could have passed4 ,the next bad place was about a mile after the second pass across the ,san ,jos ,river1 being a very deep and abrupt vale4 ,had we never passed the ,san ,jos ,river1 but left it on our right hand1 the road would have been much shorter1 and we should have avoided this deep vale1 and also the three other vales1 and their three rivers of ,montelegre1 ,juan ,mora1 and ,ajerbi4 ,they were1 however1 small1 not more than half the leg in water1 which is a proof that their source was not above #aj miles off and must have originated in the side of the high ridge on our left4 ,none of the vales were impassable to mules1 except that between the second passing of the river ,san ,jos and the river ,montelegre1 which was about a mile1 and might be made passable for mules by a diagonal road to be made in the side of the hill a little higher up4 ,only five or six miles of road would require to be made for mules on the whole of the way we came1 to where the river ,serapique is navigable4 ,we observed that we should have avoided those vales by passing a few miles more to the left1 where we saw one continued high ridge running from the highest ridge of the continent1 commencing at the volcano and terminating in a point near to where the ,serapique ,river is navigable4 ,on a regular decline for perhaps #gjjj or #hjjj feet in height1 down to near sea-level1 which would in that distance have given a fall of about half an inch in a yard1 four men in ten days would make1 ,i have no doubt1 this ridge passable for mules on a regular descent to where the ,serapique ,river is navigable4 ,i have no doubt if we could have spent one week more on our journey we might have passed mules the whole distance with us4 ,to carry machinery from where the ,serapique is navigable to the mines is about one-third farther than from the port of ,arenas on the south1 on which the carriage is two dollars per mule load2 three dollars might therefore be charged per mule from the ,atlantic side1 a much less cost than by way of ,matina1 or by going around ,cape ,horn4 ,it would give a speedy communication and a great accommodation to the province of ,costa ,rica1 which ,i doubt not would gladly contribute to its making4 ,the mining district occupies the mountain of ,aquacate1 nearly equidistant from the port of ,punta de ,arenas1 in the ,gulf of ,nicoya1 and from ,san ,jos1 the capital of the state1 about #ad leagues from the former and #ab from the latter4 ,the high road passes through the centre of the district4 ,the chief outlay after paying for the mines would be for erecting stamping mills and making railroads4 ,this broken information barely gives an idea of the importance of the ,costa ,rica mines1 or of what ,trevithick did between the time of his landing on the ,pacific shore1 about #ahbb1 and his leaving the mines on his search for a new route over the ,cordillera to the ,atlantic shore1 about #ahbf or #ahbg4 ,judging from the rough map on which ,trevithick has marked his line of travel across the isthmus1 the mines of ,machucha1 ,quebrada-honda1 and ,coralillo1 were inland from the ,gulf of ,nicoya1 on the ,pacific1 some forty or fifty miles1 the latter mine having its water shed into the ,rio ,grande1 while the two other mines1 not far off1 opened into the ,quebrada-honda ,river4 ,the central high ridge of the ,cordillera was between the mines and the ,atlantic2 indeed the mines are on high ground at the foot of volcanic mountains4 ,san ,mateo seems to have been the place of importance near the mines1 and probably a well-known mule-track was in use through the mountain ridge to ,san ,jos1 the capital1 once numbering thirty thousand inhabitants2 but this line failed to reach a good port on the ,atlantic coast4 ,the travellers1 therefore1 abandoned the known track1 and turning to the left1 made their way between the volcanic peaks of ,potos and ,barba1 hoping that on the eastern slope of the ,cordillera navigable rivers would be found either to the ,atlantic or to the ,san ,juan de ,nicaragua1 which joined the ,atlantic at the port of ,san ,juan4 ,it was probably at this volcanic ridge that the precipitous road obliged the mules to be sent back4 ,the track was then due north1 towards ,buona ,vista1 below which the river ,serapique took its rise1 running into the river ,san ,juan4 ,where they crossed this river was fifty or sixty miles from where the mules had left them4 ,trevithick marked the river-crossing with a steamboat1 indicating its navigability2 but the writer infers that it had so much of the mountain torrent about it1 that the travellers took a line still through unexplored country towards the port of ,san ,juan1 on the ,atlantic1 for the track and the description show that the river ,san ,jos was crossed1 and also another river running to the ,atlantic4 ,they probably were stopped by swamps on approaching the ,san ,juan1 and retracing their steps to the ,serapique1 constructed rafts or canoes1 and after hairbreadth escapes sailed down it to the junction with the ,san ,juan1 and down the latter to its junction with the ,atlantic at ,port ,san ,juan1 or ,greytown4 ,eleven days were passed from the parting with the mules near the crossing of the highest ground1 from whence they saw a continuous ridge1 commencing at the volcano and terminating near to where the ,serapique is navigable on a regular decline for perhaps seven or eight thousand feet down to near sea-level1 giving a fall for the whole distance of about half an inch in a yard1 or in railway parlance #a in #gj2 for this was what was in ,trevithick's head1 that his steam-horse should carry where the mule could not1 and that miners and machinery should be so taken to his mines from the ,atlantic1 giving those who chose an opportunity of continuing their railway journey to the ,pacific4 ,the writer has heard ,trevithick describe the excursion as lasting three weeks1 through woods1 swamps1 and over rapids2 their food1 monkeys and wild fruit2 their clothes1 at the end of the journey1 shreds and scraps1 the larger portion having been torn off in the underwood4 ,mr4 ,thomas ,edmonds also listened to ,trevithick's narrations1 some of which he gives in the following3-- ,in #ahcj ,i frequently saw ,trevithick at the house of ,mr4 ,gittins1 at ,highgate1 a schoolmaster1 with whom were two boys that had accompanied him from ,costa ,rica1 called ,montelegre4 ,before ,captain ,trevithick no ,european had adventured on or explored the passage along the river from the ,lake ,nicaragua to the sea4 ,in the adventure he was accompanied by ,mr4 ,j4 ,m4 ,gerard1 a native of ,scotland2 two boys of ,spanish origin going to ,england for their education2 a half-caste1 as servant to ,mr4 ,gerard2 and by six working men of the country1 of whom three went back1 after helping to remove obstructions in the forest through which the first part of the journey was undertaken4 ,the risks to which the party were exposed on their passage were very great3 they all had a narrow escape from starvation1 one of the labourers was drowned1 and ,captain ,trevithick was saved from drowning by ,mr4 ,gerard4 ,the intended passage was along the banks of the river4 ,to avoid the labour of cutting through the forest1 the party determined to construct a raft1 on which they placed themselves1 their provisions1 and utensils2 after a passage of no long duration they came to a rapid1 which almost overturned their raft1 and swept away the principal part of their provisions and utensils4 ,the raft1 being unmanageable1 was then stopped by a tree lying in the river1 with its roots attached to the bank2 on this tree three of the passengers1 including ,captain ,trevithick1 landed1 and reached the bank2 this was no sooner done than the current drove the raft away from the tree1 and carried it1 with the remaining passengers1 to the opposite bank1 where they landed in safety1 and abandoned the raft as too dangerous for further use4 ,the next object was to unite the party again into one body4 ,the three left on the other side of the river were called upon to swim over3 one of the men swam over in safety1 the next made the attempt and was drowned1 the third and last remaining was ,captain ,trevithick1 who was either unable to swim or could swim very little4 ,in order to improve his chances of safety1 he gathered several sticks1 which he tied in a bundle and placed under his arms2 with these he plunged into the stream2 but the contrivance of the bundle of sticks afforded him very doubtful assistance1 for the current appeared to seize the sticks and whirl him round and round4 ,he1 however1 finally reached within two or three yards of the bank in a state of extreme exhaustion4 ,mr4 ,gerard going into the water himself and holding the branch of a tree1 then threw to his assistance the stem of a water-plant1 holding one of the extremities in his own hand4 ,it was not until the fourth time of throwing that ,captain ,trevithick was able to seize the very extremity of the plant 7which was leaf7 in his fingers2 on the strength of the leaf his life on the occasion was dependent4 ,it was determined to give up any further idea of using a raft on the river1 and to continue their journey along the banks of the river4 ,for subsistence for the remainder of their journey they had to depend on the produce of one fowling-piece and a small quantity of gunpowder2 after a few days the gunpowder got wet by accident1 and in the attempt to dry it1 it was lost by explosion4 ,the party finally arrived in a state of great exhaustion at the village1 now the considerable port of ,san ,juan de ,nicaragua1 or ,greytown2 and shortly after their arrival a small vessel arrived1 which conveyed the party to one of the ,west ,india islands4 ,upon one occasion ,captain ,trevithick was called upon to act in a novel capacity1 that of a surgeon4 ,an accident happened to a native engaged in working an engine erected at a place distant about two hundred miles from ,lima1 by which accident both of his arms were crushed4 ,there was no medical man within the distance of two hundred miles1 and ,captain ,trevithick1 believing that death would ensue if amputation was not immediately performed1 offered his services1 which were accepted by the patient4 ,the operation1 he informed me1 was successful2 the man rapidly recovered1 and showed a pair of stumps which could have hardly been distinguished from the result of an operation by a regular surgeon4 ,it is not improbable that in the warfare in which he had been engaged ,captain ,trevithick had been present and assisted at amputations of limbs of wounded soldiers4 ,he thus probably acquired sufficient confidence to undertake and perform the operation himself4 ,from ,costa ,rica ,captain ,trevithick came to ,england1 with a design1 among others1 of forming a company to work a mine which had been granted him 7for a term of years7 by the ,costa ,rica ,government4 ,mr4 ,gerard came to ,england with a similar object in view4 ,both failed in their object4 ,mr4 ,gerard was extremely unfortunate with regard to his mine1 for he spent a considerable fortune of his own in working his mine to a loss4 ,the eminence of ,captain ,trevithick as an engineer is well known4 ,the public are indebted to him for the invention of the high-pressure steam-engine and the first railway steam-carriage4 ,the latter being dependent on the former1 ,captain ,trevithick informed me that the idea of the high-pressure engine occurred to him suddenly one day whilst at breakfast1 and that before dinner-time he had the drawing complete1 on which the first steam-carriage was constructed4 ,captain ,trevithick informed me that in #ahcj the original steam railway-engine constructed by him in #ahjhacb at that time was still running in ,wales4 ,footnote #acb3 ,probably referring to the ,welsh locomotive of #ahjd4 ,,sir1 ,,stanwik1 ,,cumberland1 #bgth ,november1 #ahfd4 ,i read in the public prints that in a speech made by you in ,belle ,vue ,gardens you referred to the meeting of ,robert ,stephenson with ,trevithick at ,carthagena1 which1 if your speech be correctly reported1 you attribute to accident4 ,the meeting was not an accident1 although an accident led to it1 and that accident nearly cost ,mr4 ,trevithick his life2 and he was taken to ,carthagena by the gentleman that saved him1 that he might be restored4 ,when ,mr4 ,stephenson saw him he was so recovering1 and if he looked1 as you say1 in a sombre and silent mood1 it was not surprising1 after being1 as he said1 'half drowned and half hanged1 and the rest devoured by alligators1' which was too near the fact to be pleasant4 ,mr4 ,trevithick had been upset at the mouth of the river ,magdalena by a black man he had in some way offended1 and who capsized the boat in revenge4 ,an officer in the ,venezuelan and the ,peruvian services was fortunately nigh the banks of the river1 shooting wild pigs4 ,he heard ,mr4 ,trevithick's cries for help1 and seeing a large alligator approaching him1 shot him in the eye1 and then1 as he had no boat1 lassoed ,mr4 ,trevithick1 and by his lasso drew him ashore much exhausted and all but dead4 ,after doing all he could to restore him1 he took him on to ,carthagena1 and thus it was he fell in with ,mr4 ,stephenson1 who1 like most ,englishmen1 was reserved1 and took no notice of ,mr4 ,trevithick1 until the officer said to him1 meeting ,mr4 ,stephenson at the door1 ',i suppose the old proverb of two of a trade cannot agree is true1 by the way you keep aloof from your brother chip4 ,it is not thus your father would have treated that worthy man1 and it is not creditable to your father's son that he and you should be here day after day like two strange cats in a garret2 it would not sound well at home4' ',who is it8' said ,mr4 ,stephenson4 ',the inventor of the locomotive1 your father's friend and fellow-worker2 his name is ,trevithick1 you may have heard it1' the officer said2 and then ,mr4 ,stephenson went up to ,trevithick4 ,that ,mr4 ,trevithick felt the previous neglect was clear4 ,he had sat with ,robert on his knee many a night while talking to his father1 and it was through him ,robert was made an engineer4 ,my informant states that there was not that cordiality between them he would have wished to see at ,carthagena4 ,the officer that rescued ,mr4 ,trevithick is now living4 ,i am sure he will confirm what ,i say1 if needful4 ,a letter will find him if addressed to ,no4 #d1 ,earl ,street1 ,carlisle1 ,cumberland4 ,there are more details1 but ,i cannot state them in a letter1 and you might not wish to hear them if ,i could4 ,i am1 ,sir1 ,your very obedient servant1 ,,james ,,fairbairn1 who writes as well as rheumatic gout will let him4 ,p4,s4--,i forgot to say the name of the officer is ,hall4 ,to ---- ,,watkin1 ,esq4 ,,dear ,,sir1 #d1 ,,earl ,,street1 ,,carlisle1 #afth ,december1 #ahfd4 ,on my return from ,liverpool this day ,i find your letter of the #ith4 ,in reply ,i have the honour to say that if you will be pleased to state upon what points you require information1 ,i shall be but too happy to furnish it if ,i can4 ,i have barely time to add that ,mr4 ,fairbairn has left for ,america1 which is his home1 and has been for many years4 ,he must have been at ,birkenhead or ,liverpool at the date of your letter to me4 ,i was not aware that he had written to you4 ,he brought me a paper with your remarks about the meeting of ,mr4 ,robert ,stephenson and ,mr4 ,trevithick1 and asked me if it were true that they met at ,carthagena as stated1 as he 7,mr4 ,fairbairn7 thought it was at ,angostura1 and that ,mr4 ,trevithick was in danger of being drowned at the ,bocasses1 i4 e4 the mouths of the ,orinoco1 the ,apure1 c1 c4 ,i explained that it was near the mouth of the ,magdalena4 ,i will just say that it was quite possible ,mr4 ,r4 ,stephenson had forgotten ,mr4 ,trevithick1 but they must have seen each other many times4 ,this was shown by ,mr4 ,trevithick's exclamation1 ',is that ,bobby8' and after a pause he added1 ',i've nursed him many a time4' ,i know not the cause1 but they were not so cordial as ,i could have wished4 ,it might have been their difference of opinion about the construction of the proposed engine1 or it might have been from another cause1 which ,i should not like to refer to at present2 indeed1 there is not time4 ,pray address me as before4 ,i hold no rank in the ,british service1 and in ,england never assume any4 ,i have the honour to be1 dear ,sir1 ,faithfully yours1 ,,bruce ,,napier ,,hall4 ,,edward ,w4 ,,watkin1 ,esq41 ,m4,p41 c41 ,currente ,calamo4 ,these notes from ,mr4 ,hall and ,mr4 ,fairbairn to ,mr4 7now ,sir ,edward7 ,watkin#acc arose from the latter repeating what ,mr4 ,robert ,stephenson had related1 of his meeting with ,trevithick and ,gerard at the inn at ,carthagena4 ,stephenson said1 on his way home from ,colombo1 and in the public room at the inn1 he was much struck by the appearance and manner of two tall persons speaking ,english2 the taller of them1 wearing a large-brimmed straw or whitish hat1 paced restlessly from end to end of the room4 ,gerard and ,stephenson entered into conversation1 and ,trevithick joined them4 ,stephenson said that he had a hundred pounds in his pocket1 of which he gave fifty to ,trevithick to enable him to reach ,england4 ,it seems that had it not been for ,mr4 ,hall's quick eye and steady hand rescuing ,trevithick from the jaws of the blind alligator1 he never would have returned to his native country4 ,footnote #acc3 ,sir ,edward ,watkin contemplated writing a life of ,trevithick4 ,here was the inventor of the locomotive a beggar in a strange land1 helped by the man whom he had nursed in baby-boyhood1 then returning to ,england to become a great railway engineer in making known the use of the locomotive on the level road of the ,liverpool and ,manchester1 while the real inventor1 who looked upon railways and locomotives as things of a quarter of a century before1 was about to recommend them as the means of passing across the isthmus of ,costa ,rica from the ,atlantic to the ,pacific1 over the heights of the ,cordillera1 by the river ,san ,juan from ,greytown1 and by its tributary the ,serapique1 then by railway towards the high ground of ,san ,jos1 the capital1 and down the western slope1 passing1 somewhere not far from the mines1 forward to the ,gulf of ,nicoya in the ,pacific4 ,the approximate distance would be fifty miles of river navigation1 and eighty or a hundred of railway1 with perhaps stiffish but still manageable inclines1 and no avalanches4 ,a loan by the ,costa ,rica ,government of #ahgb states1#acd for the completion of the railway from the port of ,limon1 in the ,atlantic ,ocean1 to ,san ,jos de ,costa ,rica1 and on to ,heredia and ,alajuela1 near to ,trevithick's mines1 as if to carry out his design of forty-six years ago to connect the ,atlantic and ,pacific by railway4 ,footnote #acd3 ,see ',the ,times1' #gth ,may1 #ahgb4 ,,chapter ,,xxiv4 ,,return ,,to ,,england4 ,in the early part of ,october1 #ahbg1 the writer1 then a boy at ,bodmin school1 was asked by the master if any particular news had come from home4 ,scarcely had the curiosity of the boys subsided1 when a tall man with a broad-brimmed ,leghorn hat on his head entered at the door1 and after a quick glance at his whereabouts1 marched towards the master's desk at the other end of the room4 ,when about half-way1 and opposite the writer's class1 he stopped1 took his hat off1 and asked if his son ,francis was there4 ,mr4 ,boar1 who had watched his approach1 rose at the removal of the hat1 and replied in the affirmative4 ,for a moment a breathless silence reigned in the school1 while all eyes were turned on the gaunt sun-burnt visitor2 and the blood1 without a defined reason1 caused the writer's heart to beat as though the unknown was his father1 who eleven years before had carried him on his shoulder to the pier-head steps1 and the boat going to the ,south ,sea whaler4 ,during the next six months father and son sat together daily1 the one drawing new schemes and calculations1 the other observing1 and learning1 and calculating the weight and size and speed of a poor swallow he had shot1 that the proportions of wings necessary to carry a man's weight might be known4 ,in these calculations cube roots of quantities were extracted1 which did not accurately agree with ,trevithick's figures1 who1 asking for explanations1 received a rehearsal1 word for word1 of the school-book rule for such extractions1 which threw no more light on his understanding than did his own self-made rule on the writer's comprehension1 though both methods produced nearly the same result4 ,within a month of that time he heard of the arrival in ,england of ,mr4 ,gerard1 his companion in travel1 from whom he had separated at ,carthagena4 ,,my ,,dear ,,good ,,sir1 ,,hayle ,,foundry1 #aeth ,november1 #ahbg4 ,i cannot express the extreme pleasure that the receipt of your favour of the #aath inst4 from ,liverpool gave me1 as ,i had almost given up hopes of ever seeing you again1 which you will see from the letters that ,i wrote ,mr4 ,lowe2 and after the severe rubs that we have undergone together1 the parting us by shipwreck1 as ,i supposed1 at the close of our hardships1 ,i doubly felt1 and from your long absence1 ,i supposed you must have encountered some severe gales2 but thank ,god that we are safe landed to meet you and the dear boys again soon4 ,we had a very good passage home1 six days from ,carthagena to ,jamaica1 and thirty-four days from thence for ,england2 and on my return was so fortunate as to join all my family in good health1 and also welcomed home by all the neighbourhood by ringing of bells1 and entertained at the tables of the county and borough members1 and all the first-class of gentlemen in the west of ,cornwall1 with a provision about to be made for me for the past services that this county has received from my inventions just before ,i left for ,peru1 which they acknowledge to be a saving in the mines since ,i left of above #ejj1jjjl41 and that the present existence of the deep mines is owing to my inventions4 ,i confess that this reception is gratifying1 and have no doubt but that you will also feel a pleasure in it4 ,i should be extremely happy to see you down here2 it is but thirty-six hours' ride1 and it will prepare you for meeting your ,london friends1 as ,i would take you through our mines and introduce you to the first mining characters1 which will give you new ideas and enable you to make out a prospectus that will show the great advantages in ,costa ,rica mines over every other in ,south ,america4 ,i think it would not be amiss for you to bring with you a few specimens1 and after you have seen the ,cornish mines and miners ,i doubt not but we shall be able to state facts in so clear a light that the first blow well aimed will be more than half the battle1 and prove a complete knock-down blow1 which in my opinion ought to be completed previous to your opening your mining speculation in general in ,london4 ,i have made a very complete model of the gun1 and it is approved of by all who have seen it4 ,be so good as to remember me to the lads and the ,manilla man1 and write me by return of post4 ,i have not as yet made any inquiry about the probability of getting adventurers for this new concern4 ,i hope and trust that ,i shall see you in ,cornwall previous to our being together in ,london1 as it is my opinion that the nature of the concern requires it4 ,i remain1 ,sir1 ,your humble servant1 7,signed7 ,,richard ,,trevithick4 ,,mr4 ,,jno4 ,,gerard1 ,no4 #db1 ,st4 ,mary ,axe1 ,london4 ,trevithick's hopeful character enabled him to enjoy life in the midst of neglect and poverty4 ,during the eleven years of absence in ,america his wife and family received no assistance from him4 ,shortly after leaving his ,quebrada-honda mountains of gold and silver1 he was penniless at ,carthagena4 ,on reaching ,england he possessed nothing but the clothes he stood in1 a gold watch1 a drawing compass1 a magnetic compass1 and a pair of silver spurs4 ,his passage-money being unpaid1 a chance friend enabled him to leave the ship4 ,in a month from that time he counted on getting a share of the #ejj1jjjl4 saved in the ,cornish mines by the improvements he had effected in their steam-engines4 ,the ringing of bells and the talk of the neighbourhood made him forget that he was a poor man1 and the ,costa ,rica mines were1 he believed1 soon to be in full working1 though not a single adventurer had been found4 ,the two lads ,montelegre1 coming to ,england to be educated1 were sons of a gentleman of influence and authority in ,costa ,rica4 ,on their perilous journey an attack of measles increased their discomforts4 ,probably one of those gentlemen has since filled the honourable position in this country of minister representing the ,republic of ,costa ,rica4 ,,my ,,dear ,,sir1 ,,london1 ,november #agth1 #ahbg4 ,i arrived here from ,liverpool last night1 and this morning had the pleasure of receiving your kind letter of the #aeth4 ,the brig ',bunker's ,hill1' in which we came from ,carthagena to ,new ,york1 was wrecked within a few hours' sail of the port4 ,we were in rather a disagreeable situation for some time1 but more afraid than hurt4 ,the cargo was nearly all lost4 ,the ship was got off1 but a complete wreck4 ,the cause1 however1 of my delay in arriving arose from the want of the needful4 ,you recollect ,mr4 ,stephenson and ,mr4 ,empson1 agents for the ,colombian ,mining ,association1 whom we met at ,carthagena4 ,they kindly offered to supply me1 but having determined to visit the celebrated ,falls of ,niagara1 they insisted on my accompanying them1 which ,i did4 ,i am truly rejoiced to learn that your countrymen retain so lively a sense of the importance of your services4 ,i think with you that before sounding the public or proceeding further1 it might be well we should meet quietly to talk over everything and arrange our ideas1 and that ,cornwall1 for the reasons you mention and others1 would be the better place4 ,the boys are well1 and desire their respects to you4 ,your sincere friend1 ,j4 ,m4 ,,gerard4 ,,capt4 ,,trevithick4 ,trevithick was friendly with ,george ,stephenson when1 in #ahje1 he nursed little ,bobby4 ,twenty years afterwards1 when ,george had comprehended ,trevithick's locomotive1 and desired his son's return to ,england to assist him in making it useful1 ,robert ,stephenson1 grown to manhood1 met his father's friend in the wilds of ,central ,america1 both of them having been engaged in mining operations1 and both on their return to ,england4 ,george ,stephenson's son made for himself a fortune and a name1 his friend earned poverty and neglect4 ,these two men1 though well known to the engineering world1 had no mutual attraction1 and in their native land remained strangers to each other4 ,,my ,,dear ,,sir1 #db1 ,,st4 ,,mary ,,axe1 ,january #acth1 #ahbh4 ,i had very unexpectedly a letter from ,costa ,rica this morning by the way of ,jamaica1 including two for you1 which ,i have the pleasure of transmitting4 ,mine is from ,montelegre1 begun on the #beth of ,august1 and finished on the #aath of ,september1 when ,don ,antonio ,pinto1 with some people from the ,alajuela1 was to start by the road of ,sarapique on his way to ,jamaica4 ,his intention was to find a better route as far as ,buona ,vista1 after which he would probably nearly follow our course to the ,embarcadero of ,gamboa4 ,whether he succeeded in finding a less rugged road to ,buona ,vista ,i do not know4 ,that he reached his destination seems clear from our letters having come to hand2 but from their old date it would appear that he had either met with difficulties on the road or with considerable detention at ,san ,juan4 ,montelegre writes me that ,don ,yonge had effected a compromise on your account with the ,castros4 ,gamboa got back to ,san ,jos on the #ahth ,august1 twelve days after he parted from us1 to the great joy of our mutual friends4 ,mr4 ,paynter had been unwell after our departure4 ,both he and ,montelegre desire their kindest recollections to you ,yours most sincerely1 ,j4 ,m4 ,,gerard4 ,,capt4 ,,trevithick4 ,the newly-discovered track taken by the homeward bound over the ,cordilleras soon brought ,don ,antonio ,pinto and others into the field in search of passable roads to the ,atlantic4 ,twelve days required by ,gamboa to effect his return to ,san ,jos1 a distance of perhaps sixty miles1 indicate the difficulty4 ,mr4 ,gerard passed some weeks with ,trevithick in ,cornwall arranging the best means of getting together a company to work on a large scale the ,costa ,rica mines4 ,,dear ,,sir1 ,,hayle ,,foundry1 ,january #bdth1 #ahbh4 ,yesterday ,i saw ,mr4 ,m4 ,williams1 who informed me that he should leave ,cornwall for ,london on next ,thursday week1 and requested that ,i would accompany him4 ,if you think it absolutely necessary that ,i should be in town at the same time1 ,i would attend to everything that would promote the mining interest4 ,when ,i met the ,messrs4 ,williams on the mining concerns some time since1 they mentioned the same as you now mention of sending some one out with me to inspect the mines1 and that they would pay me my expenses and also satisfy me for my trouble with any sum that ,i would mention1 because such proceedings would be satisfactory to all who might be connected in this concern4 ,i objected to this proposal on the ground that a great deal of time would be lost and that the circumstances of your contracts in ,san ,jos would not admit of such a detention2 for that reason alone was my objection grounded1 and if that objection could have been removed ,i should have been very glad to have the mines inspected by any able person chosen for that purpose1 because it would not only take off the responsibility from us1 but also strengthen our reports1 as the mining prospects there will bear it out1 and that far beyond our report4 ,some time since ,i informed you that ,i had drawn on the company for #ajjl4 to pay #gjl4 passage-money1 and would have left #cjl4 to defray my expenses returning to ,london4 ,the time for payment is up1 but ,i have not as yet heard anything about it1 therefore ,i expect there must be an omission by the bankers whose hands it was to have passed through for tendering it for payment4 ,perhaps in a day or two ,i shall hear something about it2 ,i would thank you to inform me should you know anything about it4 ,the unfavourable result of the gun ,i attribute in a great measure to the change in the ,ministry and my not being present to explain the practicability of making the machinery about it simple4 ,when ,lord ,cochrane has seen it1 and a meeting takes place with him1 my return to ,london may again revive its merits4 ,this unfavourable report does not lessen its merits1 neither will it deter me from again moving forward to convince the public of its practicability4 ,i shall make immediately a portable model of the iron ship and engine1 as they will be applicable to packets1 which have been attempted at ,falmouth1 but found that the consumption of coals was so great that the whole of the ships' burthen would not contain sufficient coals to take them to ,lisbon and return again1 and on that account it was discontinued4 ,that insurmountable object will now be totally removed1 and ,i think that ,lord ,cochrane will make a very excellent tool to remove many weak objections made by persons not having sufficient ability to judge for themselves4 ,his ,lordship1 being a complete master of science1 is capable of appreciating their value from theory and from practice4 ,i should not be surprised to see him down here to inspect it4 ,it will be very agreeable if his ,lordship comes here at the same time as yourself2 he is a remarkably pleasant companion4 ,my hearty thanks for your mother's good wishes towards me4 ,your humble servant1 ,,rd4 ,,trevithick4 ,,mr4 ,,jno4 ,,gerard1 ,no4 #db1 ,st4 ,mary ,axe1 ,london4 ,gerard and ,trevithick believed in the great value of the ,costa ,rica mines1 and in the feasibility of working them profitably could capital sufficient be obtained4 ,after a year or two passed in fruitless attempts to form a mining company in ,england1 ,mr4 ,gerard visited ,holland and ,france with no better success2 and while on this mission died in poverty in ,paris1 though brought up in youth as the expectant inheritor of family estates in ,scotland4 ,one of his letters says3-- ,robert ,stephenson has given us his experience that it was unwise to take many ,english miners or workers to such countries4 ,the chief reliance must after all be placed on the native inhabitants1 under the direction and training of a small but well-selected party of ,englishmen4 ,mining operations in that country are of such recent origin that a mining population can scarcely be said to exist4 ,english workmen are not so manageable even in this country1 and much less so in ,spanish ,america1 where they are apt to be spoiled by the simplicity and excessive indulgence even of the better classes1 and where the high salaries they receive place them far above the country people of the same condition4 ,all this tends to presumption and intolerance on their part1 and ultimately to disputes and irreconcilable disgusts between them and the natives4 ,mr4 ,michael ,williams1 ,mr4 ,gibson1 ,mr4 ,macqueen1 and others1 were anxious to take up the mining scheme4 ,the former proposed to send a person to examine the mines4 ,this was a safe course1 but not convenient to those who had made engagements to return without loss of time with miners and material to ,costa ,rica4 ,mr4 ,m4 ,williams informed the writer's brother that at a meeting of several gentlemen in ,london1 a cheque for #hjjjl4 was offered to ,trevithick for his mining grant of the copper mountain in ,south ,america4 ,words waxed warm1 and the proffered money was refused4 ,the next day ,mr4 ,williams said to him1 ,why did you not pocket the cheque before you quarrelled with them8 ,trevithick replied1 ,i would rather kick them down stairs6 ,in the end ,trevithick got nothing for either his ,south ,american mines or those in ,costa ,rica4 ,,chapter ,,xxv4 ,,gun-,,carriage--,,iron ,,ships--,,hydraulic ,,crane--,,ice ,,making--,,drainage ,,of ,,holland--,,chain-,,pump--,,open-,,top ,,cylinder--,,hayle ,,harbour--,,patent ,,rights--,,petition ,,to ,,parliament4 ,richard ,trevithick1 of the parish of ,saint ,erth1 in the county of ,cornwall1 civil engineer1 maketh oath and saith that he hath invented new methods for centering ordnance on pivots1 facilitating the discharge of the same1 and reducing manual labour in time of action4 ,that he is the true inventor thereof1 and that the same hath not been practised by any other person or persons whomsoever to his knowledge or belief4 ,sworn1 #ajth ,november1 #ahbg1 before me1 ,rd4 ,edmonds4 ,this gun is worked by machinery balanced on pivots giving it universal motion1 by one man1 with the facility of a soldier's musket4 ,on one side a man puts in a copper charge of powder2 on the opposite side a man drops a ball in a bag down the gun1 as it stands muzzle up4 ,the gunner1 who sits on the seat behind the gun1 points it and pulls the trigger4 ,the firing causes it to run up an inclined plane at an angle of #be for the purpose of breaking the recoil2 it runs down again with its muzzle at the port1 requiring no wadding1 swabbing1 cartridge1 or ramming1 but runs in1 out1 primes1 cocks1 shuts the pan1 and breaks the recoil of itself2 and by three men can be fired three times in a minute with accuracy4 ,the gun-carriage is a tube #c feet long and #c feet diameter1 made of wrought-iron plate #a_/d of an inch thick1 centered on a pivot to the deck1 with the gunner's seat attached1 from which he looks through the case4 ,as the gun requires no tackle1 and but a man on each side to work it1 only a space of #e feet #f inches is required from centre to centre of ports1 therefore a single-deck ship will carry a greater number of guns than are now carried on a double-deck ship1 be worked with one-third of the hands1 and be fired five times as fast as at present4 ,a frigate would mount fifty #db-pound guns on one deck1 with #aej men1 and would discharge in the same time a greater weight of ball with greater precision than five #gd-;gun ships4#ace ,footnote #ace3 ,description in ,trevithick's handwriting4 ,illustration3 ,,trevithick',s ,,gun-,,carriage ,,and ,,friction ,,slides1 #ahbg4 ,,hayle1 ,,cornwall1 #bast ,february1 #ahbh4 ,,my ,,lord ,,cochrane1#acf ,with great pleasure ,i read in the papers the announcement of your arrival again in ,england1 and am much gratified to find a person of your superior natural and practical talents1 so rare to be obtained1 to whom ,i may communicate my views4 ,i have proposed to ,government to build an iron ship1 and a gun on a new principle1 which are to undergo an investigation1 and have lodged a drawing of the ship and a model of the gun with my friend ,mr4 ,gerard1 a gentleman who returned with me from ,america1 and who will present to you this letter with the above-mentioned drawing and model4 ,i have had an iron boat made for the purpose of sending it to ,london1 to show the method of constructing ships on this plan1 roomy1 strong1 and cheap4 ,also a wrought-iron ship with a steam-engine on an improved principle1 which in a few days will be laid on the stocks at the ,hayle ,foundry iron manufactory4 ,footnote #acf3 ,rough draft1 by ,trevithick1 of unfinished letter4 ,though ,lord ,cochrane was just the person to be interested in such schemes1 it does not appear that he took any part in them4 ,at that time he was at work on his own particular ideas for marine propulsion4 ,,my ,,dear ,,sir1 ,,london1 ,february1 #ahbh4 ,immediately after the receipt of your last1 which ,i only received after twelve o'clock on the #gth1 ,i went to the ,ordnance ,office1 where1 though ,colonel ,gossett was no longer an official personage1 ,i had the good luck to meet him4 ,he told me that the model of the gun was at ,woolwich1 and could not be got at in time to stop the progress of the other patent1 and which he considered of but little moment1 as he thought it very unlikely there could be any collision between the two inventions4 ,he likewise said that from the official changes that had taken place in the office1 much loss of time might be incurred by recalling the model1 which was in train of being examined4 ,to-day ,i have received a letter addressed to you from the ,ordnance1 by which it appears that your model has passed through an unsuccessful ordeal before the special committee4 ',,sir1 ',,office ,,of ,,ordnance1 #bast ,february1 #ahbh4 ',i am directed by the ,master ,general to acquaint you that the ,select ,committee of ,artillery ,officers1 to whom your model of a #db-pounder carronade and carriage on a new principle were referred1 have reported that on examination of the invention1 they consider it to be wholly inapplicable to practical purposes4 ,your model is at the ,ordnance ,office1 and will be delivered on your sending for it4 ',i am1 ,sir1 ',your most obedient humble servant1 ',,lowndes4 ',r4 ,,trevithick1 ,esq4' ,my poor mother1 who ,i regret to say has been very delicate ever since your departure1 and is now again confined to bed1 desires me to say that she is very sorry she is not ,master ,general of the ,ordnance1 to give it a fair practical trial1 as she thinks ,captain ,trevithick's opinions1 though she cannot pronounce his name1 may be fairly placed in opposition to that of the special committee of artillery officers4 ,ever faithfully yours1 ,j4 ,m4 ,,gerard4 ,the recoil gun-carriage was his first occupation after twelve years of travel in countries where mechanical appliances were less thought of than weapons of war4 ,he commenced this1 his second era of inventions1 with what he called a new thing1 though it was but an extension of his schemes of #ahji1 when he patented iron vessels1 hollow sliding masts and yards1 self-reefing sails1 and sliding keels4 ,the model gun was of brass1 resting on a railway formed of two inclined bars of iron1 up which the recoil propelled it into a convenient position for cleaning and loading4 ,its own gravity caused it to fall into the required place for being again fired4 ,the slides also served as friction-bars to regulate the recoil4 ,the gun and the slides carrying it were enclosed in a wrought-iron box1 having openings in the front and rear for the passage of the muzzle and the breech4 ,the muzzle front of the box was pivoted to the deck by a strong bolt as a centre of motion1 whilst its rear was supported on two small wheels resting on the deck1 allowing the gun to change its line of horizontal fire by sweeping from the centre pivot4 ,the gunner's seat moved with the carriage1 from which he could elevate or depress the muzzle by a lever4 ,the gun was self-priming and self-cocking2 the powder charge was enclosed in a copper case4 ,captain ,moncrieff's patent gun-carriage of the present day is described in words somewhat like those used by ,trevithick forty years before4 ,the recoil lifted a weight smoothly and without friction2 the gun and the weight were held in the position arrived at by a catch until the gun was loaded and ready to fire again4#acg ,footnote #acg3 ,see ',the ,times1' ,august #abth1 #ahgj4 ,the iron boat mentioned in his note to ,lord ,cochrane as being made at ,hayle1 was for the purpose of sending to ,london to show the method of constructing ships on this plan1 roomy1 strong1 and cheap1 and was thus spoken of in a newspaper of the #bfth ,april1 #ahbi4 ,the ',scotsman' alludes to the intended construction of iron steamboats at ,glasgow by ,mr4 ,neilson3--,for fear of the public being misled on this subject1 we beg to state that so far back as last ,christmas twelvemonths we saw ,trevithick1 of ,cornwall1 superintending the construction of an iron man-of-war launch1 with the avowed intention of applying a similar principle of construction to the building of fast-sailing iron steamboats4 ,this intimation1 in #ahbi1 to the since famous ,glasgow iron-ship builders1 that they could not claim the invention because ,trevithick had made such a boat in #ahbg1 was probably in ignorance of ,trevithick's patent and models of #ahji1ach explaining the advantages of ships of iron1 either under sail or under steam1 for commerce or for fighting-ships4 ,the improved high-pressure steam-engine then in hand for iron ships was but the perfecting of his plans of twenty years before4#aci ,footnote #ach3 ,see vol4 i41 p4 #cjb4 ,footnote #aci3 ,see vol4 i41 p4 #cbi4 ,,lauderdale ,,house1 ,,highgate1 ,april #aith1 #ahcj4 ,,mr4 ,,gilbert1 ,sir1--,i find by looking into the ',art of ,gunnery' that a #db-lb4 shot discharged at the rate of #bjjj feet a second in vacuum would send it to the height of #fc1cfj feet1 which multiplied by the weight of the shot would be #b1ffa1abj lbs41 with #ab lbs4 of powder2 and as guns1 after being heated to about the heat of boiling water1 will recoil their usual distance with half their first charge of powder1 it proves that one-half the powder at first is lost in heating the gun to about #bab1 which is a great deal under the heat of fired powder1 therefore only #f lbs4 of powder effective force is applied to the ball4 ,now suppose this #f lbs4 of powder to be one quarter part carbon1 #a-a_/b lb4 is all the heat that can possibly be applied to perform this duty2 then #a lb4 of carbon would be equal to #a1ggd1jhj lbs4 of duty actually performed2 but if you take into calculation the great loss of power by the powder not being instantly all set on fire1 with the gun so much below the heat of fired powder1 the windage by the sides of the shot1 the ball flying from the powder1 and the immense power remaining in the gun at the time of the ball leaving its muzzle2 if this was applied expansively1 as in a cylinder1 it may fairly be said to have double this power1 or #c1edh1afj lbs4 for #a lb4 of carbon consumed1 which1 multiplied by #hd1 being the pounds in #a bushel of carbon1 gives #cjj millions of duty4 ,if it was applied to the best advantage1 say on a piston1 calling powder one thousand atmospheres1 it would far exceed that duty4 ,a gun #i feet long and #g-;inch bore has #af feet of cold sides1 and condenses at first one-half of its force by its cold sides and loses #aej millions in a #bjjth part of a second1 while the ball passes from the breech to the muzzle4 ,this gives #bba1gfj lbs4 condensed by each foot of surface sides in so short a time4 ,binner ,downs cylinder was taken as condensing #bejj lbs4 for each surface foot in six seconds2 therefore1 without taking into account the great difference in time1 there is eighty-eight times as much power lost by each foot of cold sides of the gun as by the cylinder sides4 ,this shows what a considerable power is lost by cold sides where the vapour is so rare4 ,boulton and ,watt's engine1 doing twenty millions1 performs with #a lb4 of coal a duty of #bdj1jjj lbs41 or about #a_/adth part of what is done by #a lb4 of carbon in powder4 ,the water evaporated by the boiler is #g lbs4 thrown into steam by #a lb4 of coal1 and a duty of #cc1gej lbs4 for each pound of water evaporated4 ,suppose #a lb4 of powder to contain #ab oz4 of nitre and #d oz4 of carbon1 and #a_/bdth part of the nitre to be a fixed water1 which would be half an ounce of water in every pound of powder1 making the carbon eight times as much as the water2 from this data #a lb4 of water in powder would perform a duty of #bh1che1bhj lbs4 lbs4 #a lb4 of carbon in powder #c1edh1afj #ad times the consumption #a lb4 of coal in ,boulton and ,watt's engine #bdj1jjj by the engine4 #a foot of cold sides of the gun #bba1gfj #hh times as much loss #a of the cylinder #cc1gej by the cold sides of the gun #a lb4 of coal for #g lbs4 of water in #ad times as much coal steam for water into steam #a lb4 of carbon for #h oz4 of water in powder as for water in powder powder4 ,by this it appears that heat is loaded with fourteen times as much water in steam-engines as in powder1 and does only #a_/adth part of the duty of the water in powder4 ,it is possible to heat steam independent of water1 because if we work with steam of ten atmospheres1 it would have ten times the capacity for heat1 being in proportion to its gravity4 ,the boiler standing on its end1 with the fire in the bottom1 and the water #a foot thick above it1 with a great number of small tubes from bottom to top1 having great surface sides to heat the steam above the water1 by working with a low chimney and slow fire1 the tubes in the steam part of the boiler would not exceed #fjj or #gjj of heat1 which would not injure them2 as less water would be generated into steam1 a very small part of the boiler would be sufficient for it2 and as the coal required would be less1 the boiler required would be very small4 ,i state the foregoing to remind you that but little is yet known of what heat may be capable of performing2 as this data so far exceeds whatever has been calculated on the power of heat before1 when compared with steam in an engine4 ,the power is sure1 if we can find how to conduct it4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,if you can spare time please to write to me4 ,the foregoing may be classed either under cannon or steam-engine2 ,,trevithick combined them under the general laws of expansion by heat4 ,three years had passed since the committee of artillery officers sitting on his gun had given a verdict of no go2 yet the subject was not forgotten1 and his calculations enabled him to discover the explosive force1 and the speed of the projectile in different parts of the gun1 things which are now ascertained by mechanical tests and measures4 ,if a #g-;inch cannon #i feet long loses by absorption of heat during the time of the passage of the shot to the muzzle one-half of the expansive force of the powder1 it is time to wrap our guns as well as our steam-engines in non-conductors4 ,the greater heat of exploded powder than of steam caused eighty-eight times the amount of loss from abstracted heat1 and yet the force from a pound of carbon in powder1 was fourteen times as much as the ,watt engine gave from a pound of coal4 ,,mr4 ,,giddy1 ,,london1 ,,no4 #db1 ,,st4 ,,mary ,,axe1 ,june #ahth1 #ahbh4 ,sir1--,a few days since a ,mr4 ,linthorn called on me and requested me to accompany him to ,cable ,street1 near the ,brunswick ,theatre1 to see a crane worked by the atmosphere1 in a double-acting engine attached to it4 ,he has a patent1 and has entered into a contract with the ,st4 ,katharine's ,dock ,company to work their cranes1 #adj in number1 by a steam-engine of sufficient power to command the whole of them1 by placing air-pipes around the docks1 with a branch to each crane4 ,to each crane is fixed a #aj-;inch cylinder1 #bj-;inch stroke1 double-acting4 ,the atmosphere pressing on the piston like steam1 the air is drawn from the pipes by a large air-pump and steam-engine4 ,on being requested to give my opinion on this plan1 after seeing one crane worked1 ,i informed them of the disappointment that the ironmaster1 ,mr4 ,wilkinson1 in ,shropshire1 several years since experienced1 on the resistance of air in passing through long pipes from his blast-engine to his furnaces4 ,he said he was aware of that circumstance1 and it had since been further proved in ,london by one of the gas companies attempting to force gas a considerable distance1 and who also failed4 ,he thought that forcing an elastic fluid1 and drawing it by a vacuum1 were very different things1 and that the error was removed by drawing in place of forcing4 ,for my part ,i am not convinced on this head2 but am still of opinion that the result on trial will be found nearly the same4 ,however1 let that be as it may1 the expense and complication of the machine1 having a double engine1 with its gear attached to every separate crane1 together with the immense quantity of air thrown into the air-pump from #adj double engines of #aj inches diameter1 #bj-;inch stroke1 eighty strokes per minute1 and considering the numerous air leaks in such an extent of pipes and machines1 must reduce the effect of the pressure of the atmosphere on each piston to a comparatively small power1 unless the air-pump and steam-engine are beyond all reasonable bounds4 ,those objections ,i made them acquainted with1 and said that1 before they went to such an expense1 it would be a safer plan to first make further inquiry1 so that their first experiment might be on a sure plan1 for the other dock companies were looking for the results of this experiment4 ,at the time ,i was informed of this plan1 a thought struck me that it might be accomplished by another mode preferable to this3 by a steam-engine to force water in pipes round the dock1 to say #cj or #dj lbs4 to the inch1 more or less1 and to have a worm-shaft1 working in a worm-wheel1 the same as a common roasting-jack1 and apply to the worm-shaft a spouting arm like ,barker's mill2 the worm-shaft standing perpendicular would work the worm-wheel fixed in the chain-barrel shaft of the crane4 ,this would make a very simple and cheap machine1 and produce a circular motion at once1 instead of a piston alternating motion to drive a rotary motion4 ,my report had some weight with them2 inquiry is to be made into the plan proposed by me1 so as to remunerate me1 provided my plan is considered good4 ,mr4 ,linthorn wishes an investigation before scientific and able judges1 and requested me to name some one4 ,i must again make free in asking the favour of your advice 7which you have so ably given me for thirty years7 on this plan4 ,mr4 ,linthorn intends to request ,dr4 ,wollaston to accompany you1 any day convenient to you4 ,in the meantime1 should you see him1 it might not be amiss to mention it to him2 and should you be able to attend for an hour or two to this business1 ,i would thank you to drop me a note1 saying when it may be convenient4 ,there is a memorandum of an agreement between ,mr4 ,linthorn and me2 but the plan ,i suggest is only at present made public to him and yourself4 ,your most obedient servant1 ,,richard ,,trevithick4 ,the reduction of friction by the use of an air-vacuum engine for working cranes1 as designed by ,mr4 ,linthorn1 in lieu of an air-pressure engine1 was doubted by ,trevithick4 ,the ,mont ,cenis pneumatic-pressure machines which the writer saw at work lost much power by friction before experience had taught remedies4 ,the pneumatic vacuum tubes which propelled the trains on the ,south ,devon ,railway1 failed to give the power that was expected4 ,sir ,william ,armstrong's hydraulic cranes1 brought into use not many years after the date of ,trevithick's letter1 have been found effective4 ,the writer1 not knowing that ,trevithick had before recommended hydraulic cranes for warehouses1 accompanied ,sir ,william over his works1 then being erected near ,newcastle-on-,tyne1 and talked with him on the detail of his crane designs4 ,trevithick thought of giving circular motion to the crane chain-barrel by the attachment of a screw-propeller1 acted on by the force of a current of water at a pressure of #cj or #dj lbs4 to the inch4 ,sir ,william ,armstrong's arrangement was quite different2 the merit due to ,trevithick was for having pointed out the suitability of water as a means of conveying power through warehouses where fire was inadmissible4 ,,mr4 ,,gilbert1 ,,london1 #db1 ,,st4 ,,mary ,,axe1 ,june #bith1 #ahbh4 ,sir1--,fancy and whim still prompt me to trouble you1 and perhaps may continue to do until ,i exhaust your patience4 ,a few days since ,i was in company where a person said that #ajj1jjjl4 a year was paid for ice1 the greatest part of which was brought by ships sent on purpose to the ,greenland seas4 ,a thought struck me at the moment that artificial cold might be made very cheap by the power of steam-engines2 by compressing air in a condenser surrounded by water1 and an injection to the same1 so as to instantly cool down the highly-compressed air to the temperature of the surrounding air1 and then admitting it to escape into liquid4 ,this would reduce the temperature to any state of cold required4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,trevithick's ideas for making ice have since been patented and made useful1 though the detail of the operation has been improved by experience4 ,the ,dutch1 extending the use of steam on the ,rhine and also in sea-going ships1 wished ,trevithick to see what was going on in ,holland1 where his nephew1 ,mr4 ,nicholas ,harvey1 was actively engaged in engineering4 ,he had not money enough for the journey1 and borrowed #bl4 from a neighbour and relative1 ,mr4 ,john ,tyack4 ,during his walk home a begging man said to him1 ,please your honour1 my pig is dead2 help a poor man4 ,trevithick gave him #es4 out of the #djs4 he had just begged for himself4 ,how he managed to reach ,holland his family never knew2 but on his return he related the honour done him by the ,king at sundry interviews1 and the kindness of men of influence in friendly communion and feasting4 ,,mr4 ,,gilbert1 ,,london1 ,july #cast1 #ahbh4 ,sir1--,the night before last ,i arrived from ,holland1 where ,i spent ten days4 ,i found my relative there1 ,mr4 ,nicholas ,harvey1 the son of ,john and ,nancy ,harvey4 ,he is the engineer to the ,steam ,navigation ,company at ,rotterdam4 ,they have a ship #bce feet long1 #aejj tons burthen1 with three #ej-;inch cylinders double1 also two other vessels #aej feet long1 each with two #ej-;inch cylinders double1 ready to take troops to ,batavia4 ,the large ship with three engines cost #hj1jjjl4 ,the ,steam ,navigation ,company built them1 and many others of different sizes4 ,this company has been anxious to get me to ,holland1 having heard of the duty performed by the ,cornish engines4 ,they were anxious to know what might be done towards draining and relieving ,holland from its ruinous state4 ,immediately on arrival ,i joined the ,dutch company1 and entered into bonds with them4 ,i give you1 as near as ,i can1 the present state of the country4 ,about #bej years since1 a strong wind threw a bank of sand across the mouth of the river ,rhine1 which made it overflow its banks2 #hj1jjj lives were lost1 and about #dj1jjj acres of land1 which remain to this time under #ab feet of water4 ,about #ajj years since the head and surface of the river ,rhine was #e feet below what it now is4 ,the under floors of houses in ,holland are nearly useless1 and in another century must be totally lost1 unless something is done to prevent it4 ,the river at present is nearly overflowing its banks4 ,in consequence of the rise of water1 the windmill engines cannot lift it out4 ,to erect steam-engines1 they never could believe would repay the expense4 ,nearly one-half of ,holland is at present under water1 either totally or partially1 because the ground kept dry in winter is flooded in summer4 ,about six years since it was in contemplation to recover the #dj1jjj acres before mentioned1 and a company was formed of the ,king and the principal men in ,holland1 to drain this by windmills1 which they estimated would cost #bej1jjjl41 and making the banks and canals #dej1jjjl4 more1 when made by men's labour1 and seven years to accomplish it4 ,this seven years was a great objection1 because of the unhealthy state of the country while draining4 ,the water is about #ah inches every year1 to be lifted on an average #aj feet high4 ,i have been furnished with correct calculations and drawings from this company4 ,they expected to have drained #dj1jjj acres in seven years1 at a cost of #gjj1jjjl41 which1 when drained1 would have sold at #ejl4 per acre1 about two millions4 ,i find1 from the statement given me1 of #ah inches of water to be lifted #aj feet high1 it would require about one bushel of coal to lift the water from one acre of ground for one year1 and that a #fc-;inch cylinder double would perform the work of #dj1jjj acres1 when working with high steam and condensing1 at an expense of less than #cjjjl4 per year4 ,engines in boats would cut and make the embankments and canals1 without the help of men4 ,i proposed six cylinders of #fj inches diameter1 double power1 which would drain the water in one year2 and also four others for cutting the canals and making embankments4 ,the expense would not exceed #ajj1jjjl4 and one year1 instead of #gjj1jjjl4 and seven years4 ,above #fj1jjj acres more are to be drained4 ,it was also proposed by ,government to cut open the river ,rhine to #ajjj yards wide and #f feet deep for #ej or #fj miles in length2 they supposed it would cost them ten millions sterling4 ,i proposed to make iron ships of #ajjj tons burthen1 with an engine in each1 which would load them1 propel1 and also empty them for about #a;d4 per ton4 ,each ton will be about a square yard1 and the cutting the river ,rhine #ajjj yards wide1 #f feet deep1 #ej or #fj miles in length1 will not cost one and a half million1 and be accomplished in a short time4 ,i further proposed that all this rubbish be carried into the sea of the ,zuyder ,zee1 which would make dry1 by embanking with the rubbish1 nearly #a1jjj1jjj acres of good land1 capable of paying ten times the sum of cutting open the river ,rhine4 ,all this would add #ajj per cent4 more to the surface of ,holland1 and at this time it is much wanted1 because their settlements abroad are free almost of the mother-country1 and they have too many inhabitants for the land at present4 ,i made them plans for carrying the whole into effect1 and have closed my agreement with them4 ,in a few days ,i shall go to ,cornwall1 and promised to return again to ,holland within a month4 ,i saw ,mr4 ,hall and the engineer of the ,dock ,company to-day4 ,they are satisfied that the plan for working the cranes is a good one4 ,i am to see them again on ,monday next2 after which ,i shall return home1 where ,i hope to see you1 to consult you on the best plan for constructing the machines for lifting the water1 cutting the canals1 and making the dykes4 ,i remain1 ,sir1 ,your very obedient servant1 ,,richard ,,trevithick4 ,in this mere outline of a life it is impossible to go fully into the merit of ,trevithick's plans for doubling the land surface of ,holland4 ,a drainage company was formed in ,london with a board of directors1 some of whom thought that a new kind of engine should be invented and patented as a means of excluding others from carrying on similar but competing operations4 ,trevithick1 always ready to invent new things1 though never forgetting his experience with old things1 instinctively returned to the ,dolcoath engines1 and recommended them as suitable for the pumping work2 but finally a new design was determined on1 and ,harvey and ,co41 of ,hayle1 received orders for the construction1 with the greatest possible dispatch1 of a pumping engine for ,holland4 ,this happening shortly after the writer had been taken from the ,bodmin school1 he was desired to help in the erection of this engine1 and after working-hours made a drawing of its original form4 ,plate ,,xv4 a1 iron barge2 b1 wood frame supporting pump2 c1 open-top steam-cylinder #c feet diameter1 #h-;feet stroke2 d1 piston guide-wheel2 e1 connecting rod2 f1 fly-wheel2 g1 cranked axle working air-pump bucket2 h1 connecting rod for air-pump bucket2 i1 air-pump2 j1 condenser2 k1 steam and exhaust nozzles2 l1 eccentrics working steam and exhaust valves2 m1 steam-pipe2 n1 cylindrical boiler1 with internal fire-tube2 o1 external brick flues2 p1 chimney2 q1 feed-pump2 r1 feed-pipe2 s1 cup or rag-wheel2 t1 rag-chain1 with iron balls2 u1 pump-barrel1 #c feet diameter2 v1 wheel guiding balls into bottom of pump-barrel2 w1 launder4 ,illustration3 ,,plate #ae ,,trevithick',s ,,chain ,,and ,,ball ,,pump4 ,london3 ,e4 ,f4 ,n4 ,spon1 #dh1 ,charing ,cross ,kell ,bros4 ,lith ,london ,after a few successful though noisy trials1 an alteration was made in the endless chain and in the guide-roller near the pump bottom4 ,an amount of slack in the chain caused the balls to knock on passing this roller before entering the pump bottom4 ,a chain having long links or bars of iron of uniform length1 from ball to ball1 jointed together by cross-pins1 was substituted for the short link chain1 and passed over a revolving hollow square frame at the bottom of the pump1 in place of the curved roller-guide in the drawing4 ,each of the four sides of this square hollow frame was of the same length as the jointed link1 and the balls lay in the hollow of the frame without touching it1 contact being only on the links4 ,the balls were thus guided directly into the bottom of the pump on their upward course with a rigid chain1 and the swing and knocking was avoided4 ,this pump was in principle the traditional rag-and-chain pump of a hundred years before2 yet no trace of its use is met with during ,trevithick's life in ,cornwall4 ,the early pump had rag balls1 in keeping with the mechanical ignorance of the time1 and suitable to man's power4 ,trevithick's pump with iron balls raised #gbjj gallons of water #aj feet high in a minute with #a-a_/b lb4 of coal1#adj retaining all the original simplicity of the earlier rag-pump1 having uniform circular motion and constant stream1 without the use of a single valve4 ,the engine and pump are thus described by him3-- ,footnote #adj3 ,see letter1 vol4 ii41 p4 #ccb4 ,the first engine that will be finished here for ,holland will be a #cf-;inch cylinder and a #cf-;inch water-pump1 to lift water about #h feet high4 ,on the crank-shaft there is a rag-head of #h feet diameter1 going #h feet per second1 with balls of #c feet diameter passing through the water-pump1 which will lift about #ajj tons of water per minute4 ,it is in an iron boat1 #ad feet wide1 #be feet long1 #f feet high1 so as to be portable and pass from one spot to another without loss of time4 ,this will drain #ah inches deep of water 7the annual produce on the surface of each acre of land7 in about twenty minutes2 to drain each acre with about a bushel of coal costing #f;d4 per year4 ,the engine is high pressure and condensing4#ada ,footnote #ada3 ,see ,trevithick's letter1 vol4 ii41 p4 #cae4 ,it was something like the ,newcomen open-topped cylinder of a hundred years before1 but with a heavy piston1 on the top of which a guide-wheel equal in diameter to the cylinder turned on a pin1 to which the main connecting rod was jointed4 ,the guide-wheel prevented any tendency to twist the piston from the angular positions of the connecting rod1 and allowed the crank-shaft to be brought comparatively near to the cylinder top4 ,the boiler was cylindrical1 of wrought iron1 with internal fire-tube and external brick flues2 and gave steam of about #dj lbs4 on the inch above the atmosphere1 which1 acting under the piston1 caused the up-stroke1 an expansive valve reducing the average pressure in the cylinder by one-half4 ,the down-stroke was made by the atmospheric pressure of #ad lbs4 on the inch1 on the piston1 its lower side being in vacuum1 together with the weight of the thick piston and connecting rod1 and the momentum of the revolving parts4 ,my readers must not suppose that this was an attempt to revive the discarded ,newcomen engine2 the likeness was only apparent2 its power was mainly from the use of strong expansive steam1 giving motion in the up-stroke through a rigid connecting rod1 with controlling and equalizing crank and fly-wheel4 ,it was not1 as the ,newcomen1#adb dependent for its power on the atmospheric pressure2 and having no cylinder cover1 or parallel motion1 or beam1 was not a ,watt engine1 though it had the ,watt air-pump and condenser4 ,footnote #adb3 ,see vol4 i41 p4 #e4 ,the ,dolcoath engines continued to work with open-topped cylinders a quarter of a century after the ,watt patent2 and when they had passed away1 many of ,trevithick's high-pressure steam-engines retained the same form of outline1 but had neither cylinder covers1 parallel motion1 air-pump1 nor vacuum4 ,the agricultural engines of #ahacadc and the ,south ,american engines of #ahafadd had neither cylinder cover nor any other part of the ,watt engine1 yet they successfully competed with it in power1 economy1 and usefulness4 ,footnote #adc3 ,see vol4 ii41 p4 #cg4 ,footnote #add3 ,see vol4 ii41 p4 #bjh4 ,this design reveals a stumbling-block that superficial people fall over4 ,the boiler in the boat was surrounded by brick flues1 while a life-long claim of ,trevithick's is that before his tubular boiler with internal fire1 there could not be a successful steamboat1 because brick flues were dangerous in sea-going vessels1 but in an iron boat in smooth water it answered its purpose without in any respect falsifying ,trevithick's former claims or plans4 ,the chain pumping machine was in an iron barge1 the #cf-;inch diameter pump fixed just outside the bow1 its lower end a foot in the water2 its height of #h or #i feet enabled the water from the pump-head to flow through launders over the banks of the lakes to be drained4 ,some of the directors came to ,hayle to see it work1 and were well pleased at the constant stream of water rushing from the foaming pump-head into the launders4 ,the large size of the rag-wheel gave the rapidly revolving chain and balls a great speed4 ,in passing through the pump each ball forced upwards the water above it1 and drew up after it the following water2 before any ball had passed out at the top of the pump the following ball had entered its bottom4 ,the directors having desired the writer to take the engine to ,holland and set it to work with the least possible delay1 adjourned for refreshment before starting for ,london4 ,in those few minutes differences arose1 resulting in the engine remaining for months in the barge1 and then going to the scrap heap4 ,years afterwards others acted on ,trevithick's drainage ideas1 and ,harvey and ,co4 built ,cornish pumping engines with steam-cylinders #aab inches in diameter1 similar in principle to the ,dolcoath engine#ade of #ahaf1 which effectually drained the ,haarlem lake4 ,footnote #ade3 ,see vol4 ii41 p4 #afh4 ,the ,rhine during #ajj years1 in its passage through the low flat lands1 had by deposit raised the level of its waters #e feet1 threatening to overflow the embankments and drown the surrounding country1 that to a large extent was at a lower level than the river4 ,all drainage from such land had to be pumped over the river bank1 in many places #aj feet above the cultivated surface4 ,windmills had been used as pumping power1 and a company had contemplated laying out #gjj1jjjl4 in windmills and canals for drainage4 ,if the surface water averaged #ah inches in depth yearly1 ,trevithick could by steam-engines drain an acre of land by the consumption of a bushel of coal yearly4 ,four engines with cylinder of #fc inches in diameter would drain #afj1jjj acres1 and four smaller engines in barges with suitable apparatus were to cut canals and construct embankments4 ,the deposit of a hundred years was also to be removed1 and the ,rhine deepened #f feet for a breadth of #ajjj yards1 and a length of #ej or #fj miles1 by steam-dredgers1 as used twenty years before in deepening the ,thames1#adf to be fixed in iron ships of a thousand tons burthen4 ,the cost of dredging from the bed of the river into a barge would be #a;d4 per ton2 but this would be more than repaid by making with it an embankment1 enclosing the ,zuyder ,zee1 which would then in its turn be drained and made pasture land4 ,footnote #adf3 ,see vol4 i41 p4 #bdc4 ,before leaving for ,america he had reported on the best means of improving ,st4 ,ives ,bay4#adg ,hayle ,harbour was a branch of it1 and he now suggested to ,mr4 ,henry ,harvey methods for deepening and improving it4 ,a rival company of merchants and engineers1 known then as ,sandys1 ,carne1 and ,vivian1 after many fights had recourse to law on the question of the course of a stream which had been changed by alterations during the making of wharfs and channels for ships4 ,footnote #adg3 ,see vol4 i41 p4 #cdc4 ,trevithick made a model in wood1 movable layers of which indicated changes of level caused by workmen at different periods1 giving a different course to the river bed4 ,mr4 ,harvey's counsel1 since known as ,lord ,abinger and ,sir ,william ,follett1 complimented ,trevithick on the facility of understanding the case by reference to the model4 ,the writer having carried the surveying chain1 was present at the trial at the ,bodmin assizes in #ahbi4 ,,mr4 ,,gilbert1 ,,hayle ,,foundry1 ,september #adth1 #ahbi4 ,sir1--,i expected to have seen you before this1 but am detained by ,mr4 ,harvey's attorney to settle the ,foundry ,quay4 ,as ,i made the drawing and model of the disputed ground1 and was examined in evidence in court1 it was thought proper that ,i should be present at the time that ,mr4 ,peters came to determine the boundary line between the two companies4 ,this cannot be concluded for ten days4 ,as ,i have been so long detained ,i wish to await your arrival in ,cornwall for the purpose of trying the new engine while you are down1 and will thank you to inform me when you intend to be with us4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,erskine1 who had expressed the opinion favourable to ,trevithick's engine more than twenty years before1#adh was in this trial the counsel for the opposing side4 ,the verdict was in favour of ,mr4 ,harvey1 or ,trevithick's side4 ,footnote #adh3 ,see vol4 ii41 p4 #abi4 ,a former chapter#adi speaks of promises to pay certain savings by the use of ,trevithick's inventions prior to his leaving for ,america4 ,the ,united ,mines refused to continue the payment1 and on ,mrs4 ,trevithick's application to ,mr4 ,davies ,gilbert for advice he kindly wrote to the ,williamses1 who managed those mines1 and received the following reply3-- ,footnote #adi3 ,see vol4 ii41 p4 #ajh4 ,,dear ,,sir1 ,,scorrier ,,house1 ,november #adth1 #ahbj4 444 with regard to ,mrs4 ,trevithick's claims for savings on engines at the ,united ,mines1 there is much to be said4 ,before ,mr4 ,trevithick went abroad he sold half the patent right to ,william ,sims1 our engineer1 who very strongly recommended that two of the engines at the ,united ,mines should be altered to what he considered his patent principle1 but the alterations proved very inferior to his expectations1 and to this circumstance ,i attribute much of the objections in question4 ,mr4 ,henry ,harvey has perhaps told you who the partners are in the patent1 and when you next come into this county ,i shall be much pleased to wait on you at ,tredrea that you may hear the whole of the case2 and though the ,united ,mines adventurers are far from being a united body1 ,i am very sure my sons1 who are their managers1 are desirous to recommend what appears to them right1 and they will with myself be obliged for your opinion after you have heard the whole matter on both sides4 ,dear ,sir1 ,yours very sincerely1 ,,jno4 ,,williams4 ,,davies ,,gilbert1 ,esq41 ,m4,p4 ,the opinion of ,mr4 ,williams' elder son1 ,michael1 has been given4#aej ,some of the family were quakers4 ,no further money payment for the saving of fuel followed this carefully civil note1 until ,trevithick1 on his return from ,america1 called at ,scorrier ,house in a very threatening attitude on #cast ,october1 #ahbg1 when ,mr4 ,williams1 sen41 said his reason for not continuing the payment was from his belief that the term of the patent had expired4 ,then came the following lawyer's letter3-- ,footnote #aej3 ,see letter from ,mr4 ,michael ,williams1 vol4 ii41 p4 #aji4 ,,sir1 ,,penzance1 #gth ,november1 #ahbg4 ,i was at ,captain ,trevithick's yesterday1 who observed to me he saw you at ,scorrier a few days ago1 and requested you would be good enough to settle the arrears on the savings on some of the engines in the mines for which you acted1 none having been paid for a year or two1 when you stated that the payment had been discontinued on account of the patent having expired4 ,i find on a reference to the patent that it will not expire till ,may1 #ahcj4 ,i am1 ,sir1 ,your obedient servant1 ,,rd4 ,,edmonds4 ,,john ,,williams1 ,esq41 ,scorrier4 ,,sir1 ,,hayle1 ,january #bdth1 #ahbh4 ,yesterday ,i called on ,mr4 ,williams1 and after a long dispute brought the old man to agree to pay me #aejl4 on giving him an indemnification in full from all demands on ,treskerby and ,wheal ,chance ,mines in future4 ,he requested that you should make out this indemnification4 ,i could not possibly get them to pay more1 and thought it most prudent to accept their offer rather than risk a lawsuit with them4 ,i remain1 ,sir1 ,your obedient servant1 ,,richard ,,trevithick4 ,,rd4 ,,edmonds1 ,esq4 ,treskerby and ,wheal ,chance were1 ,i believe1 the only mines that paid for the use of the pole patent4 ,mr4 ,john ,williams1 sen41 of ,scorrier1 was purser of those mines4 ,the agreement was that patentees should have one-fourth part of the savings of coal above twenty-six millions4 ,the one-half of this fourth part from these two mines for some years was about #aejl4 per annum4 ,this did not relate to the boilers2 ,trevithick unfortunately did not take out a patent for that improvement4 ,the adventurers of two or three mines only had the honesty to pay #ajjl4 for each mine2 others made use of it without acknowledgment4 ,,rd4 ,,edmonds4 ,,penzance1 #abth ,january1 #ahec4 ,such were the recollections of the family solicitor many years after the events had passed4 ,the cylindrical high-pressure steam boiler and engine was really included in the patent of #ahjb2 but frequent detail changes1 consequent on size and position and local requirements1 were made up to #ahaa1 when a perfected form was arrived at1 which is still in use4 ,in principle it was unaltered and not materially different in form1 but being used for larger engines1 looked different4 ,the inventor saw nothing in this difference1 but the public did1 and in the absence of the only man who could prove their error refused to pay on the plea of its not being patented4 ,on his return from ,america he demanded #ajjjl4 from each of the large ,cornish mines1 as a settlement in full for all benefits derived from the use of the ,trevithick high-pressure steam-boiler4 ,he had proved the weakness of the law years before1 when three eminent counsel had given opinions on the #ahjb patent1 one of them believing the patent good1 because the principle contained was new2 two of them feared that similarity of details might invalidate it3#aea so he determined to apply to the ,government for remuneration for benefits that might be called national4 ,footnote #aea3 ,see vol4 ii1 p4 #abi4 ,,mr4 ,,rd4 ,,edmonds1 ,,hayle1 ,december #bjth1 #ahbg4 ,sir1--,i send the principal heads of what you will have to put in form to lay before the ,house4 ,it is very defective2 but you will be assisted by ,captain ,andrew ,vivian1 who can give dates and particulars1 having been engaged with ,mr4 ,gilbert and ,captain ,matthew ,moyle in making out the duty performed at that time by ,boulton and ,watt and ,hornblower's engines4 ,he can also give you the results of the late improvements1 with much more information than ,i can give4 ,i saw him yesterday for this purpose2 he will assist you with all his power1 and will call on you at ,penzance on ,friday or ,saturday4 ,as ,i shall with pleasure pay him for his trouble1 you need not fear calling on him for what assistance you need4 ,mr4 ,gerard and ,i propose to leave this for ,london on ,saturday4 ,if you think it necessary to see me1 let ,captain ,vivian know it1 and all meet at my house4 ,i have sent you one of the monthly reports1 in which you will see ,john ,lean's report of ,dolcoath engines1 from which ,i have given you in my statement the average results and savings4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,p4,s4--,i was at ,dolcoath account on ,monday1 and made known to them my intention of applying to ,government1 and not to individuals1 for remuneration4 ,they are ready to put their signatures to the petition1 and so will all the county4 ,i fear that it is as much as we shall do to get it before the ,house in time4 ,the following petition was drawn up and put into the hands of his old friend ,davies ,gilbert1 then a ,member of ,parliament3-- ,,to ,,the ,,honourable ,,the ,,commons ,,of ,,the ,,kingdom ,,of ,,great ,,britain ,,and ,,ireland ,,in ,,parliament ,,assembled4 ,the ,humble ,petition of ,richard ,trevithick1 of the ,parish of ,saint ,erth1 in the ,county of ,cornwall1 ,civil ,engineer1 #bgth ,february1 #ahbh1 ,,sheweth3 ,that this kingdom is indebted to your petitioner for some of the most important improvements that have been made in the steam-engine1 for which your petitioner has not hitherto been remunerated1 and for which he has no prospect of being ever remunerated except through the assistance of your ,honourable ,house4 ,that the duty performed by ,messrs4 ,boulton and ,watt's improved steam-engines in #agih1 as appears by a statement made by ,davies ,gilbert1 ,esq41 and other gentlemen associated for that purpose1 averaged only fourteen millions and half 7pounds of water lifted #a foot high by #a bushel of coals71 although a chosen engine of theirs1 under the most favourable circumstances1 at ,herland ,mine lifted twenty-seven millions1#aeb which was the greatest duty ever performed till your petitioner's improvements were adopted1 since which the greatest duty has been sixty-seven millions1 being more than double the former duty4 ,that prior to the invention of your petitioner's boiler the most striking defect observable in every steam-engine was in the form of the boiler1 which in shape resembled a tilted waggon1 the fire applied under it1 and the whole surrounded with mason-work4 ,that such shaped boilers were incapable of supporting steam of a high pressure1 and did not admit so much of the water to the action of the fire as your petitioner's boiler does1 and were also in other respects attended with many disadvantages4 ,footnote #aeb3 ,see ,mr4 ,taylor's report on ,herland engine1 vol4 ii4 p4 #aah4 ,that your petitioner1 who had been for many years employed in making steam-engines on the principle of ,boulton and ,watt1 and had made considerable improvements in their machinery1 directed his attention principally to the invention of a boiler which should be free from these disadvantages2 and after having devoted much of his time and spent nearly all his property in the attainment of this object1 he at length succeeded in inventing and perfecting that which has since been generally adopted throughout the kingdom4 ,that your petitioner's invention consists principally in introducing the fire into the midst of the boiler1 and in making the boiler of a cylindrical form1 which is the form best adapted for sustaining the pressure of high steam4 ,that the following very important advantages are derived from this1 your petitioner's1 invention4 ,this boiler does not require half of the materials1 nor does it occupy half the space required for any other boiler4 ,no mason-work is necessary to encircle the boiler4 ,accidents by fire can never occur1 as the fire is entirely surrounded by water1 and greater duty can be performed by an engine with this boiler1 with less than half the fuel1 than has ever been accomplished by any engine without it4 ,these great advantages render this small and portable boiler not only superior to all others used in mining and manufacturing1 but likewise is the only one which can be used with success in steam-vessels or steam-engine carriages4 ,the boilers in use prior to your petitioner's invention could never with any degree of safety or convenience be used for steam navigation1 because they required a protection of brick and mason work around them1 to confine the fire by which they were encircled1 and it would have been impossible1 independent of the great additional bulk and weight1 that boilers thus constructed could withstand the rolling of vessels in heavy seas2 and notwithstanding every precaution the danger of the fire bursting through the brick and mason work could never be effectually guarded against4 ,that had it not been for this1 your petitioner's1 invention1 those vast improvements which have been made in the use of steam could not have taken place1 inasmuch as none of the old boilers could have withstood a pressure of above #f lbs4 to the inch1 much less a pressure of #fj lbs4 to the inch1 or even of above #aej lbs4 to the inch when necessary4 ,that as soon as your petitioner had brought his invention into general use in ,cornwall1 and had proved to the public its immense utility1 he was obliged in #ahaf to leave ,england for ,south ,america to superintend extensive silver mines in ,peru1 from whence he did not return until ,october last4 ,that at the time of your petitioner's departure the old boilers were falling rapidly into disuse1 and when he returned he found they had been generally replaced by those of his invention1 and that the saving of coals occasioned thereby during that period amounted in ,cornwall alone to above #ejj1jjjl4#aec ,footnote #aec3 ,see ,lean's report1 vol4 ii41 p4 #age4 ,that the engines in ,cornwall1 in which county the steam-engines used are more powerful than those used in any other part of the kingdom1 have now your petitioner's improved boilers1 and it appears from the monthly reports that these engines1 which in #agih averaged only fourteen and half millions now average three times that duty with the same quantity of coals1 making a saving to ,cornwall alone of #b1gha1bfd bushels of coals1 or about #ajj1jjjl4 per annum4 ,and the engines at the ,consolidated ,mines in ,november1 #ahbg1 performed sixty-seven millions1 being forty millions more than had been performed by ,boulton and ,watt's chosen engine at ,herland1 as before stated4 ,that had it not been for your petitioner's invention1 the greater number of the ,cornish mines1 which produce nearly #b1jjj1jjjl4 per annum1 must have been abandoned in consequence of the enormous expense attendant on the engines previously in use4 ,that your petitioner has also invented the iron stowage water-tanks and iron buoys now in general use in ,his ,majesty's navy1 and with merchant's ships4 ,that twenty years ago your petitioner likewise invented the steam-carriage1 and carried it into general use on iron railroads4 ,that your petitioner is the inventor of high-pressure steam-engines1 and also of water-pressure engines now in general use4 ,that his high-pressure steam-engines work without condensing water1 an improvement essentially necessary to portable steam-engines1 and where condensing water cannot be procured4 ,that all the inventions above alluded to have proved of immense national utility1 but your petitioner has not been reimbursed the money he has expended in perfecting his inventions4 ,that your petitioner has a wife and large family who are not provided for4 ,that ,parliament granted to ,messrs4 ,boulton and ,watt1 after the expiration of their patent for fourteen years1 an extension of their privileges as patentees for an additional period1 whereby they gained1 as your petitioner has been informed1 above #bjj1jjjl4 ,that your petitioner therefore trusts that these his own important inventions and improvements will not be suffered to go unrewarded by the ,english nation1 particularly as he has hitherto received no compensation for the loss himself and his family have sustained by his having thus consumed his property for the public benefit4 ,your petitioner therefore most humbly prays that your ,honourable ,house will be pleased to take his case into consideration1 and to grant him such remuneration or relief as to your ,honourable ,house shall seem meet4 ,and your petitioner1 as in duty bound1 will ever pray1 c4 ,,rd4 ,,edmonds1 ,solicitor1 ,penzance4 ,from the ,patent ,office to the ,house of ,commons was1 for a petitioner1 as bad as out of the frying-pan into the fire4 ,trevithick solicited the support of ,members of ,parliament until tired of running after friends1 and the petition became a dead letter1 though the mining interests of ,cornwall had in twelve years saved #ejj1jjjl4 by his unrewarded inventions4 ,,lauderdale ,,house1 ,,highgate1 ,december #bdth1 #ahca4 ,,mr4 ,,gilbert1 ,sir1--,i find that ,mr4 ,spring ,rice cannot get the ,lords of the ,treasury to agree to remunerate or assist me in any way4 ,he appeared to be much disappointed1 and said that he would write to the ,admiralty ,board on ,thursday last1 recommending them to adopt this engine4 ,as yet ,i have heard nothing respecting it1 nor do ,i expect to during the holy days2 but in the interim ,i wish to look out for some moneyed man to join in it1 otherwise ,i fear ,i shall lose the whole4 ,can you assist in recommending anyone you know8 ,i wish ,mr4 ,thompson would come into it1 he would be a good man4 ,can you furnish me with a copy of your report to ,mr4 ,spring ,rice1 or something relating thereto8 ,it would be a great assistance in getting some one to join4 ,the sum required is small1 and the risk is less2 but the prospect is great1 beyond anything ,i ever knew offered on such easy terms4 ,waiting your reply1 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,,dear ,,trevithick1 ,,eastbourne1 ,december #bfth1 #ahca4 ,i am sorry to find that you have not any prospect of assistance from ,government4 ,i have not any copy or memorandum of my letter to ,mr4 ,spring ,rice2 but it was to the effect of first bearing testimony to the large share that you have had in almost all the improvements on ,mr4 ,watt's engine1 which have altogether about trebled its power2 to your having made a travelling engine twenty-eight years ago2 of your having invented the iron-tanks for carrying water on board ships1 c4 ,i then went on to state that the great defect in all steam-engines seemed to be the loss1 by condensation1 of all the heat rendered latent in the conversion of water into steam2 that high-pressure engines owed their advantages mainly to a reduction of the relative temperatures of this latent heat2 that ,i had long wished to see the plan of a differential engine tried1 in which the temperatures and consequently elasticities of the fluid might be varied on the opposite sides of the piston1 without condensation2 that the engine you have now constructed promised to effect that object2 and that1 in the event of its succeeding at all1 although it might not be applicable to the drawing water out of mines1 yet that for steam-vessels and for steam-carriages its obvious advantages would be of the greatest importance2 and ,i ended by saying that although it was clearly impossible for me to ensure the success of any plan till it had been actually proved by experiment1 yet judging theoretically1 and also from the imperfect trial exhibited on the ,thames1 ,i thought it well worthy of being pursued4 ,your plan unquestionably must be to associate some one with you 7as ,mr4 ,watt did ,mr4 ,boulton71 and ,i certainly think it a very fair speculation for any such person as ,mr4 ,boulton to undertake4 ,it is impossible for me to point out any individual1 as never having had the slightest connection with trade or with manufacture in any part of my life1 ,i am entirely unacquainted with mercantile concerns4 ,i cannot1 however1 but conjecture that you should make a fair and full estimate of what would be the expense of making a decisive experiment on a scale sufficiently large to remove all doubt2 and that your proposal should be1 that anyone willing to incur that expense should1 in the event of success1 be entitled to a certain share of your patent4 ,on such conditions some man of property may perhaps be found who would undertake the risk2 and if the experiment proves successful1 he will be sure to use every exertion afterwards for his own sake4 ,with every wish for your success1 ,believe me1 ,yours very sincerely and faithfully1 ,,davies ,,gilbert4 ,the petition to ,parliament for a national payment for national gains1 so hopefully taken up on his return from ,america1 when experience had proved the value of his inventions1 after four weary years of deferred expectation1 was consigned to the tomb of forgetfulness4 ,compare the petition of #ahbh with a modern report4 ,prior to the invention of your petitioner's boiler1 the most striking defect observable in every steam-engine was in the form of the boiler which in shape resembled a tilted wagon2 your petitioner's invention consists principally in introducing the fire into the midst of the boiler1 and in making the boiler of a cylindrical form1 which is the form best adapted for sustaining the pressure of high steam1 and does not require half of the materials1 nor does it occupy half the space required for any other boiler1 and greater duty can be performed by an engine with this boiler with less than half the fuel1 than by any engine without it1 and is the only one that can be used with success in steam-vessels1 as none of the old boilers could have withstood a pressure of above #f lbs4 on the inch1 much less a pressure of #fj lbs4 or even of #aej lbs4 when necessary4 ,a report of the ,royal ,mail ,steam ,packet ,company in #ahga states1 by placing compound engines in the ',tasmania1' they had reduced the consumption of coal to one-half the former quantity1 doubled her capacity for freight1 and increased her speed4#aed ,presuming that the compound engines of the ',tasmania' are like other engines known by that name1 having high-pressure steam in a comparatively small cylinder from which it expands in a larger one1 tubular boilers1 surface condensers1 and screw-propeller1 the saving admitted in the ',tasmania' is just what ,trevithick's petition pointed out forty-three years ago--to lessen by one-half the weight1 space1 and fuel in marine steam-engines--his opinion being founded on the experience of a lifetime1 for as early as #ahjd he wrote on the question of compound engines1 ,i think one cylinder partly filled with steam would do equally as well as two cylinders2#aee and again in #ahaf1 describing expansion1 ,the engine is now working with #fj lbs4 of steam1 three-quarters of the stroke expansive1 and ends with the steam rather under atmosphere strong2#aef and in the same year worked the expansive compound engine at ,treskerby4#aeg ,footnote #aed3 ,see ',the ,times1' ,october #bfth1 #ahga1 ,half-yearly ,report of the ,chairman4 ,footnote #aee3 ,see vol4 ii41 p4 #acd4 ,footnote #aef3 ,see vol4 ii41 p4 #ia4 ,footnote #aeg3 ,see vol4 ii41 p4 #ajd4 ,,chapter ,,xxvi4 ,,tubular ,,boiler1 ,,superheating ,,steam1 ,,and ,,surface ,,condenser4 ,,mr4 ,,gilbert1 ,,hayle ,,foundry1 ,december #adth1 #ahbh4 ,sir1--,on my return from ,london five weeks since ,i was disappointed at not finding you in ,cornwall4 ,i have made inquiry into the duty performed by the best engines1 and the circumstances they are under1 from which it appears to me there is something which as yet has not been accounted for1 particularly in ,binner ,downs engines4 ,a statement was given to me by ,captain ,gregor1 the chief agent and engineer of the mine1 which appears so plain that ,i cannot doubt the facts1 though they differ very widely from all former opinions4 ,there are two engines1 one of #db inches diameter1 the other of #gj inches diameter1 #aj-;feet stroke4 ,formerly those engines worked without cylinder cases1 when the #gj-;inch cylinder burnt #a-a_/b wey of coal1 and performed a regular duty of forty-one millions2 since that time brickwork has been placed round the cylinder and steam-pipes1 leaving a narrow flue1 which is heated by separate fires4 ,these flues consume about #e bushels of coal in twenty-four hours2 the heat is not so great as to injure the packing1 which stands good for thirteen weeks2 the saving for several months past has increased the duty to sixty-three millions4 ,before the use of this flue #ajh bushels of coal were consumed under the boiler1 now only #fg bushels are needed1 which with the #e bushels in the flue gives #gb bushels4 ,the coal burnt under the boiler gives a duty of sixty-six millions1 or an expansion of #fj per cent4 by the heat of #e bushels of coal in the flues1 and a duty of #agha millions gained in twenty-four hours by #e bushels of coal1 which amounts to #cej millions gained by each of these #e bushels4 ,the #db-;inch cylinder is as near as possible under the same circumstances1 no other alterations have been made2 and to prove this they left out the fires in the flues1 and the engines fell back to their former duty1 and the condensing water increased in the same proportion4 ,the surface sides heated by this #e bushels of coal is about #cjj surface feet1 the saving effected is #agha millions1 which is six millions saving for each foot of surface on the castings in the flues4 ,in ,wheal ,towan engine that did eighty-seven millions1 the surface sides of the boiler was #ajjj feet of fire-sides for every bushel of coal burnt in an hour1 and the duty performed per minute from each foot of boiler fire-sides was #aejj lbs4 #a foot high4 ,now it appears that the heating of ,binner ,downs #cjj surface feet gave a saving of #fjjj lbs4 per minute per surface foot2 whereas the boiler sides only gave #aejj lbs4 of duty per minute for each foot of boiler fire-sides4 ,therefore the saving by heating the sides of the cylinder is equal to four times the duty done by each square foot of boiler sides2 and further1 it appears that the #cjj feet1 when not heated1 though clothed round with brickwork1 condensed or prevented from expanding the steam of #da bushels of coals1 which was eight times as much steam condensed as the #e bushels of coal would raise4 ,now if this be a report of facts1 which ,i have no reason to doubt 7but still ,i will be an eye-witness to it next week71 there must be an unknown propensity in steam above atmosphere strong to a very sudden condensation1 and vice vers1 to also a sudden expansion1 by a small heat applied to the steam-sides2 and if by heating steam1 independent of water1 such a rapid expansion takes place1 certainly a rapid condensation must take place in the same ratio1 which might be done at sea by cold sides to a great advantage1 always working with fresh water4 ,i shall have a small portable engine finished here next week1 and will try to heat steam1 independent of water1 in small tubes of iron1 on its passage from the boiler to the cylinder1 and also try cold sides for condensing4 ,if the above statement prove to be correct1 almost anything might be done by steam1 because then additional water would not be wanted for portable engines1 but partially condensed and again returned into the boiler1 without any fresh supply or the incumbrance of a great quantity2 and boilers might be made with extensive fire-sides1 both to heat water and steam1 and yet be very light4 ,it appears that this engine1 when working without the heated flues round the cylinder and pipes1 evaporated #bj1jjj gallons of water into steam1 in twenty-four hours1 more than when the flues were heated1 and the increase of condensing water was in the same proportion4 ,it is so unaccountable to me that ,i shall not be satisfied until ,i prove the fact1 the result of which ,i will inform you1 and shall be very glad to receive your remarks on the foregoing statement4 ,the first engine that will be finished here for ,holland will be a #cf-;inch cylinder1 and a #cf-;inch water-pump1 to lift water about #h feet high2 on the crank-shaft there is a rag-head of #h feet diameter1 going #h feet per second1 with balls of #c feet diameter passing through the water-pump1 which will lift about #ajj tons of water per minute4 ,it is in a boat of iron1 #ad feet wide1 #be feet long1 #f feet high1 so as to be portable1 and pass from one spot to another1 without loss of time4 ,it will drain #ah inches deep of water 7the annual produce on the surface of each acre of land7 in about twenty minutes for the drainage of each acre1 with one bushel or sixpennyworth of coal per year4 ,the engine is high pressure and condensing4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,p4,s4-,woolf is making an apparatus to throw back from the bottom of the cylinder on to the top of the piston a fluid metal every stroke4 ,he says he proved by an indicator that he raised #ah1jjj inches of steam from #a inch of water1 of #aa lbs4 to the inch pressure on a vacuum1 and that the reason why this engine did not do #cjj millions1 was because the steam passed by the sides of the piston4 ,that an engine at the ,consolidated ,mines working #aj feet #b inch stroke1 going #g_/hths expansive1 beginning with steam of #bj lbs4 to the inch above the atmosphere1 and ending with #aa lbs4 on a vacuum4 ,i doubt this statement2 however1 there is some hidden theory as yet1 because some engines perform double as much as others1 under the same known circumstances1 and ,i believe that nothing but practice will discover where this defect is1 for1 in my opinion1 no statement of theory yet given is satisfactory why high-pressure engines so far exceed low-pressure engines4 ,it is facts that prove it to be so1 therefore all theory yet laid down must be defective4 ,illustration3 ,,mount',s ,,bay4 ,w4 ,j4 ,welch4 ,at the date of this letter ,trevithick had been rather more than a year in ,england1 residing generally at ,hayle1 within half-a-dozen miles of ,mount's ,bay1 from which he had sailed for ,america2 and after eleven years of wandering in countries where steam-engines were unknown1 except those that he himself had constructed1 was again on his return giving his whole thoughts to the idol of his life4 ,during that period scientific men in ,europe thought and wrote much on the question of relative temperature1 pressure1 economy1 and manageability of steam4 ,newcomen's great discovery a century before was the avoidance of the loss of heat by the cooling at each stroke of the exterior of the steam-vessel of ,savery's engine by injecting cold water into the steam in the cylinder4 ,after fifty years came the ,watt improvement1 still reducing the loss of heat by removing the cold injection-water from the steam-cylinder to a separate condenser4 ,the high-pressure steam-engine was perfect without injection-water1 though when convenient its use was equally applicable as in the low-pressure engine4 ,trevithick1 on his return to civilized life1 read the views of ,watt on steam1 as given in ',farey on the ,steam-,engine4' ,on informing ,davies ,gilbert of his doubts of the accuracy of those views1 and of his intention of testing them by comparison with the work performed by ,cornish pumping engines1 his friend1 who had just published his ',observations on the ,steam-,engine1'#aeh forwarded a copy1 from which the following is an extract3-- ,footnote #aeh3 ',observations on the ,steam-,engine1' by ,davies ,gilbert1 ,v4,p4,r4,s41 ,january #beth1 #ahbg4 ,see ',philosophical ,transactions4' ,one bushel of coal1 weighing #hd lbs41 has been found to perform a duty of thirty1 forty1 and even fifty millions1 augmenting with improvements1 chiefly in the fire-place1 which produce a more rapid combustion with consequently increased temperature1 and a more complete absorption of the generated heat2 in addition to expansive working1 and to the use of steam raised considerably above atmospheric pressure4 ,those words gave the result of ,trevithick's experience made known to his friend during twenty years of labour1#aei and yet by a seeming fatality his name is not found in his friend's book4 ,footnote #aei3 ,see letter1 vol4 ii41 p4 #adc4 ,sir ,john ,rennie1 who in youth had been employed under ,boulton and ,watt at ,soho1 and had risen to be a member of the ,royal ,society1 came about that time into ,cornwall1 at the request of the ,admiralty1 to make examination into the work performed by ,cornish pumping engines1 and selected ,wheal ,towan engine on which to make special experiments4#afj ,the subject of ,trevithick's note was therefore at that period1 and still is1 a matter of importance2 and his practical treatment of the question is more instructive to young engineers than complex rules4 ,arthur ,woolf was at the same time experimenting on steam at the ,consolidated ,mines1 and finding the want of agreement between the rules of low-pressure and the practice of high-pressure engines1 imputed the error to the escape of steam by the sides of the piston4 ,trevithick disbelieved this1 because some engines perform double as much as others1 under the same known circumstances1 and advocated the observance of general practice to prove why high-pressure engines were more economical than those of low-pressure4 ,captain ,gregor had placed fire-flues around the steam cylinder and pipes1 hoping thereby to exceed the duty of the ,wheal ,towan engine1 whose boiler1 cylinder1 and steam-pipes were carefully clothed with a thick coating of sawdust or other non-conductor of heat1 and lifted eighty-seven millions of pounds of water #a foot high by the heat from a bushel of coal weighing #hd lbs4 ,this was the greatest duty that had ever been recorded from a steam-engine4 ,the ,trevithick or ,cornish boilers1 similar to those in ,dolcoath1#afa measured at the rate of #ajjj superficial feet of heating surface for each bushel of coal burnt in an hour1 and in round numbers gave a duty of #aejj lbs4 lifted a foot high to each foot of boiler surface4 ,in words not technical1 the heat from #a lb4 of coal gave steam that raised #dfj tons weight of water #a foot high4 ,footnote #afj3 ,see vol4 ii41 p4 #ahe4 ,footnote #afa3 ,see drawing1 vol4 ii41 p4 #afi4 ,the cylinder of this engine used the ,watt steam-jacket4 ,the ,binner ,downs engine was doing not one-half this duty1 namely1 forty-one millions2 when brick flues were built around the cylinder1 cylinder cover1 and steam-pipes1 and one or two fire-places1 fixed near the bottom of the cylinder1 of a size to conveniently burn #e bushels of coal in twenty-four hours1 the heat from which circulated through those flues on its way to the chimney1 and increased the duty of the engine by one-half1 raising it to sixty-three millions2 in other words1 during twenty-four hours of working1 #fg bushels of coal in the boiler1 and #e bushels in the cylinder flues1 did the same work as #ajh bushels in the boiler without the cylinder flues1 causing a saving of fifty per cent4 by their use4 ,another startling fact was the greater effect for each foot of heating surface in the steam-cylinder flues than in the boiler flues2 the latter gave a power of #aejj lbs4 raised #a foot high by a bushel of coal1 while the former gave #fjjj lbs4 of power from the same amount of coal and heating surface4 ,here was a mystery that ,trevithick would not believe until he had seen it with his own eyes3 he searched for it for a year or two1 and overlooking the fact that the more simply arranged engine of his once pupil1 ,captain ,samuel ,grose1 was doing more duty than the superheating steam-engine at ,binner ,downs1 he worked at what seemed to be new facts1 and converted them into a new engine4 ,we have traced how succeeding engineers tried to prevent loss of heat4 ,trevithick took the first bold step1 and aiming at the same object1 made the boiler the steam-jacket for the cylinder1 and in his patent of #ahjb went still further and protected the boiler from external cold1 and thus describes it3--,the steam which escapes in this engine is made to circulate in the case round the boiler1 where it prevents the external atmosphere from affecting the temperature of the included water1 and affords by its partial condensation a supply for the boiler itself4#afb ,so that a quarter of a century before the date of those ,binner ,downs experiments he had patented an engine having neither cylinder nor boiler exposed to the cooling atmosphere4 ,the flues around the ,binner ,downs cylinder were difficult of control4 ,trevithick says the piston packing had not been injured1 showing that observers thought it would be1 and even the cylinder was endangered1 for the writer1 who stoked those heating flues1 recollects the fires burning very brightly in them4 ,the ready transmission of heat through thin metal1 used by ,trevithick in #ahjb for heating feed-water1 and in the cellular bottom of the iron ship of #ahjh1 serving as a surface condenser1#afc and his experience in #ahab1 that the cold sides of the condenser are sufficient to work an engine a great many strokes without any injection1#afd still followed up in #ahbh by condensing steam without the use of injection-water1 led to what is since known as ,hall's surface condenser4 ,footnote #afb3 ,see patent specification1 vol4 i41 p4 #acb4 ,footnote #afc3 ,see vol4 i41 p4 #cce4 ,footnote #afd3 ,see ,trevithick's letter1 #gth ,december1 #ahab1 vol4 ii41 p4 #ah4 ,the following letter is in the handwriting of the present writer2 it is the only one of ,trevithick's numerous letters not written by himself3-- ,,mr4 ,,gilbert1 ,,hayle1 ,december #cjth1 #ahbh4 ,sir1--,on the #bhth inst4 ,i received your printed report on steam1 and have examined ,farey's publication on sundry experiments made by ,mr4 ,watt1 which are very far from agreeing with the actual performance of the engines at ,binner ,downs4 ,mr4 ,watt says that steam at one atmosphere pressure expands #agjj times its own bulk as water at #bab1 and that large engines ought to perform eighteen millions when loaded with #aj lbs4 to the inch of actual work1 the amount of condensing water being one-fortieth part of the content of the steam in the cylinder at one atmosphere strength1 the cold condensing water at #ej1 and when heated #ajj4 ,this would give for the ,binner ,downs engine1 with a #gj-;inch cylinder1 #aj-;inch stroke1 #aa lbs4 effective work on the inch 7this load being one-tenth more than in ,watt's table1 by ,farey1 for an engine of this size and stroke71 #eg gallons of injection-water for each stroke1 and when working eight strokes per minute1 to do eighteen millions would consume #aa-a_/d bushels of coal per hour4 ,now the actual fact at ,binner ,downs1 at the rate of working and power above mentioned1 is that #c bushels of coal per hour were burnt1 using #ac gallons of injection-water at each stroke at #gj of heat1 which was raised by its use to #ajd1 or an increase of #cd1 which1 multiplied by #ac gallons1 gives #ddb4 ,mr4 ,watt's table for this engine and work gives #eg gallons of condensing water at #ej1 heated by use to #ajj4 ,this #ej raised1 multiplied by the #eg gallons of water1 amounts to #bhej1 or six and a half times the quantity really used in the ,binner ,downs engine1 and nearly four times the coal actually used at present4 ,mr4 ,watt further says that steam of #ae lbs4 to the inch1 or one atmosphere1 from #a inch of water at #bab occupies #aagj inches1 and that steam of four atmospheres1 or #fj lbs4 to the inch1 gives only #dga inches at a heat of #bic4 ,now deducting #ej from #bab leaves #afb of heat raised by the fire4 ,multiply #ae lbs4 to the inch by #agjj inches of steam1 and divide it by #afb1 gives #ach1 whereas if you deduct #ej from #bic1 it leaves the increase of heat by the fire #bdc4 ,steam of #fj lbs4 to the inch multiplied by #dga1 being the inches of steam made by #a inch of water divided by #bdc1 the degrees of heat raised by the coal1 gives a product of #aaf2 therefore1 by ,mr4 ,watt's view it appears that low steam would do one-fifth more duty than high steam1 and yet ,binner ,downs engine in actual work performs about four times the duty given by ,mr4 ,watt's theory and practice1 with only one-sixth part of the amount of heat carried off by the condensing water1 proving that high steam has much less heat1 in proportion to its effective force2 and this is further proved by the small quantity of condensing water required to extract its heat4 ,yesterday ,i proved this #gj-;inch cylinder while working with the fire-flues round it1 which flues only consumed #e bushels of coal in twenty-four hours4 ,the engine worked eight strokes a minute1 #aj-;feet stroke1 #aa lbs4 to the inch effective force on the piston2 steam in the boiler #de lbs4 above the atmosphere1 consuming #ab bushels of coal in four hours1 using #ac gallons of condensing water at each stroke1 which was heated from #gj to #ajd2 but when the fires round the cylinder were not kept up1 though still having the casing of hot brickwork around it1 and performing the same work1 burnt #ag bushels of coal in the same time of four hours1 and required #ae-a_/b gallons of condensing water1 which was heated from #gj to #aab4 ,you will find that the increased consumption of coal1 by removing the fire from around the cylinder1 was nearly in the same proportion as the increase and temperature of the condensing water1 showing the experiment to be nearly correct4 ,from the general reports of the working of the engines it appears that when the surface sides of the castings are heated1 either by hot air or high steam1 the duty increases nearly fifty per cent4 from this circumstance alone4 ,a further proof of the more easy condensation of high steam was in the ,binner ,downs #db-;inch cylinder engine1 #i-;feet stroke1 six strokes per minute1 #aa lbs4 effective power on each inch1 burning #a-a_/c bushel of coal an hour4 ,in this engine the proportion of saving by the heating flues was the same as in the large engine4 ,i tried to condense the steam by the cold sides of the condenser1 without using injection-water4 ,the water in the condenser cistern was at #ej4 ,after working for twenty-five minutes the small quantity of hot water discharged at the top of the air-pump reached #acj of heat1 but then would rise no higher1 the cold sides of the condenser being equal to the condensation of all the steam4 ,the eduction-pipe and air-pump1 with its bottom and top1 gave #fj feet of surface sides of thick cast iron1 and about #bj feet more of surface sides of a thin copper condenser2 altogether1 #hj feet of surface cold sides1 surrounded by cold water4 ,about half a pound on the inch was lost in the vacuum1 the discharged water being #acj of heat instead of #ajj4 ,the vacuum was made imperfect by about #a-a_/b lb4 to the inch4 ,it is my opinion that high steam will expand and contract with a much less degree of heat or cold in proportion to its effect1 than what steam of atmosphere strong will do4 ,i intend to try steam of five or six atmospheres strong1 and partially condense it down to nearly one atmosphere strong1 and then by an air-pump of more content than is usual to return the steam1 air1 and water1 from the top of the air-pump1 all back into the boiler again1 above the water-level in the boiler1 and by a great number of small tubes1 with greatly heated surface sides1 to reheat the returned steam2 though by this plan ,i shall lose the power of the vacuum1 and also the power required on the air-bucket to force the steam and water back again into the boiler1 yet by returning so much heat ,i shall over-balance the loss of power1 besides having a continued supply of water1 which in portable engines1 either on the road or on the sea1 will be of great value4 ,i shall esteem it a very great favour if you will be so good as to turn over in your mind the probable theory of those statements1 and give me your opinion4 ,if ,mr4 ,watt's reports of his experiments are correct1 how is it possible that the high-pressure engine that ,i built at the ,herland thirteen years ago1 which discharged the steam in open air1 did more than twenty-eight millions8 ,if you wish1 ,i will send a copy of the certificate of the duty done by this engine1 which states very minutely every circumstance4 ,now that cylinder1 with every part of the engine1 was exposed to the cold2 had it been heated around those surfaces1 as on the present plan1 it would have done above forty millions4 ,suppose the ,binner ,downs #gj-;inch cylinder engine1 #aj-;feet stroke1 working with full steam to the bottom of the stroke1 when1 by the experiment1 the heated flues were again laid on would have worked one-third expansive1 by the heat of #e bushels of coal around the cylinder4 ,now one-third of the power would make a #c feet #d inch stroke1 #aa lbs4 to the inch effective power1 eight strokes a minute1 during twenty-four hours1 by the consumption of #e bushels of coal applied on the surface sides of the cylinder1 performing a duty of #cbd millions with a bushel of coal4 ,now suppose the cylinder without the heating flues had the steam cut off at two-thirds of the stroke1 and that it is possible in a moment to heat the cylinder by the flues2 in that case the steam would1 by its expansion from the hot sides1 fill the last third of the cylinder to the bottom of the stroke2 then if that steam could be suddenly cooled1 so as to contract it one-third1 the piston would ascend one-third its stroke in the cylinder2 and it appears in theory by this plan1 that a cylinder once filled two-thirds full of steam1 by receiving the heat on its surface sides from #e bushels of coal1 and again suddenly cooling down1 would continue to work for ever1 without removing the steam from the cylinder1 and would perform a duty of #cbd millions4 ,this never can be accomplished in practice in this way1 but the effect may be obtained by partially condensing in a suitable condenser1 and again heating by hot sides4 ,this mystery ought to be laid open by experiment1 for what ,i have stated are plain facts from actual proofs1 and ,i have no doubt that time will show that the theory of ,mr4 ,watt is incorrect4 ,though there were #cjj feet of cold sides1 yet #bjj feet were not condensing steam1 because on the return of the piston1 what was condensed below1 and while the engine was resting1 did not make against it more than what was condensed above the piston on its descent2 therefore you may count on #aej feet of cold external sides constantly condensing1 that made this third-part difference against the expansion of the steam4 ,i remain1 ,sir1 ,your very humble servant1 ,,richd4 ,,trevithick4 ,the writer's note-book used during those experiments is in his possession1 as well as ,trevithick's note-book giving particulars of experiments at several mines1 from which the following extracts are taken3-- ,,cornwall1 ,august1 #ahbh4--,wheal ,towan #hj-;inch cylinder1 #aj-;feet stroke1 #fi strokes per minute1 loaded to #ie lbs4 on the inch of the piston1 with three of ,trevithick's boilers1 each #cg feet long1 #f feet #b inches diameter1 with fire-tube #c feet #i inches diameter1 fire-place #f feet long1 evaporated #ac square feet of water with #a bushel of coal1#afe duty #hg millions4 ,the heat in the stack was just the same as the heat of the steam in the boiler4 ,another engine of the same size on the same mine1 with similar boilers1 but working only #djf strokes per minute1 loaded to #dee lbs4 on each inch of the piston1 did #ejh millions4 ,footnote #afe3 #hd lbs4 ,wheal ,vor #ec-;inch cylinder1 #i-;feet stroke1 #fei strokes per minute1 loaded to #aieh lbs4 on each square inch of the piston1 did #cff millions4 ,wheal ,damsel #da-;inch cylinder1 #g feet #f inch stroke1 #eeb strokes per minute1 loaded to #bae lbs4 on the inch of the piston1 did #cc millions4 ,it would appear1 therefore1 that about #aj lbs4 to the inch on the piston allows of the best duty1 and that a #aj-;feet stroke exceeds in duty a #g feet #f inch stroke4 ,the ,wheal ,towan engine1 doing #hg millions1 had #abdh feet of tube fire-surface1 and a similar amount of external boiler surface in the flues4 #b-a_/b bushels of coal were consumed each hour1 giving about #ajjj feet of fire-sides for each bushel of coal consumed per hour1 and #ej feet of fire-bars4 ,those boilers were intended to supply steam for working the engine at ten strokes a minute2 a bushel of coal an hour would in that case have had #fjj feet of boiler fire-surface4 ,binner ,downs #gj-;inch cylinder1 #aj-;feet stroke1 did #da millions4 ,a fire was then put around the cylinder and steam-pipes1 which burnt #e bushels of coal in twenty-four hours1 by which the duty was increased to #fc millions4 ,the surface sides of the cylinder1 cylinder-top1 and steam-pipes heated by flues was #cjj feet1 and caused a saving of #da bushels of coal in twenty-four hours4 ,another engine in the same mine was tried1 having a #db-;inch cylinder2 when the fire was around the cylinder1 she worked #ajj strokes without injection-water2 the expansion-valve was closed at half-stroke1 the steam in the boiler #ef lbs4 on the inch above the atmosphere4 ,it is not easy to deal with the important reasonings flowing from those facts1 and influencing the form and economy of the steam-engine1 nor to show if ,trevithick was right in discrediting the laws laid down by ,watt4 ,newcomen's engine had the interior1 as well as the exterior of the steam-cylinder exposed to the cooling atmosphere4 ,watt1 by putting a cover on the cylinder1 reduced the loss of the heat from the interior1 and by his steam-case hoped to reduce the loss from the exterior1 though by it he increased the amount of surface exposed to the cold4 ,in ,trevithick's early engines the boiler alone exposed heat-losing surface1 and this was further reduced by its own comparatively small size1 the engine and boiler complete not exposing one-quarter of the surface of a ,watt low-pressure engine of equal power4 ,one object of the ,binner ,downs experiment was to further curtail this loss of power by increasing the heat of the steam while in operation in the cylinder1 since called superheating steam4 ,this principle of giving increased heat to steam1 after it had left its state as water1 was made practical by ,trevithick's boiler at ,wheal ,prosper in #ahaj1 where the flues having first been carried around the water portion of the boiler1 then passed over the steam portion2#aff and again in the upright boiler of #ahae1 having the upper end of the fire-tube surrounded by steam above the water line4#afg ,those early beginnings of superheating steam and surface condensation culminated in the ,binner ,downs experiments of #ahbh1 one immediate practical result of which was the tubular surface condenser1 enabling steamboat boilers to avoid1 in a great measure1 the use of salt water1 facilitating in a marked degree the application of marine boilers and engines with steam of an increased pressure4 ,footnote #aff3 ,see vol4 ii41 p4 #ga4 ,footnote #afg3 ,see vol4 i41 p #ced4 ,the ,binner ,downs engine1 with a cylinder of #gj inches in diameter1 and a stroke of #aj feet when working with steam in the boilers of #de lbs4 to the square inch above the atmosphere1 and using the heating flues around the cylinder1 required #ac gallons of injection-water at each stroke1 and consumed at the rate of #c bushels of coal an hour1 to produce a duty equal to eighteen millions2 by removing the cylinder superheating flues1 the quantity of injection-water for the same amount of work increased to #ae-a_/b gallons1 and the coal to #d-a_/d bushels4 ,watt's rule for his low-pressure steam vacuum engine doing a duty of eighteen millions1 gave #eg gallons of injection-water1 and #aa-a_/d bushels of coal4 ,on the question of coal1 this statement agrees very nearly with ,trevithick's letters of sixteen years before1 when he used the high-pressure boilers in the ,dolcoath pumping engine1#afh promising that his high-pressure expansive engine would do the work with one-third of the coal required in the low-pressure vacuum engine4 ,footnote #afh3 ,see vol4 ii41 p4 #aga4 ,the high-pressure steam required a less amount of injection-water to condense it than the low-pressure steam1 in proportion to the work done1 showing the ,watt rule and the ,watt experience to be inapplicable to high-pressure engines2 for instead of #eg gallons of injection-water the ,binner ,downs engine with steam of #de lbs4 to the inch required but #ae-a_/b gallons of injection-water1 and this amount was further reduced to #ac gallons by superheating the steam2 this roughly agrees with the coal consumed1 or in other words1 with the amount of heat to be carried off by injection-water3 the ,watt rule giving #aa-a_/d bushels as the fair allowance for low-pressure steam vacuum engines1 while the high-pressure steam vacuum engine burnt but #d-a_/d bushels4 ,this was further reduced to #c bushels by superheating4 ,those facts led to the idea that if the steam pressure was sufficiently increased1 condensation might be carried out without any injection-water1 by the transmission of the heat in the steam through the metal sides of the condenser4 ,an experiment was at once made by removing the ,watt condenser and injection-water1 as he had done seventeen years before1#afi using in their stead a thin copper surface-condenser immersed in cold water1 producing1 within #a_/b lb4 on the inch1 as good a vacuum as when injection-water was used1 leading to the conclusion1-- ,footnote #afi3 ,see ,query #crd1 vol4 ii41 p4 #ai4 ,it is my opinion that high steam will expand and contract with a much less degree of heat or cold1 in proportion to its effect1 than what steam of atmosphere strong will do4 ,i intend to try steam of five or six atmospheres strong1 and partially condense it down to nearly one atmosphere strong1 and then by an air-pump of more content than is usual to return the steam1 air1 and water back into the boiler again1 and by a great number of small tubes1 with greatly heated surface sides1 to reheat the returned steam4 ,this1 in practical words1 is the surface condenser by which the used steam is returned to the boiler in the form of water4 ,the more general use of high-pressure steam of #gj or #ij lbs4 to the inch1 increasing its expansive force on one side of the piston by superheating it on its passage through numbers of small tubes1 and decreasing its expansive force on the other side of the piston by cooling it in passage through similar tubes exposed to cold1 is partly effected in steamboats1 but has not yet been attempted in engines on the road4 ,after a month's further consideration he wrote3-- ,wheal ,towan engine is working with three boilers1 all of the same size1 and the strong steam from the boilers going to the cylinder-case2 the boilers are so low as to admit the condensed water to run back from the case again into the boiler3 they find that this water is sufficient to feed one of these boilers without any other feed-water1 therefore one-third of the steam generated must be condensed by the cold sides of the cylinder-case1 and this agrees with the experiments ,i sent to you from ,binner ,downs4 ,wheal ,towan engine has an #hj-;inch cylinder1 and requires #gb bushels of coal in twenty-four hours1 therefore1 the cylinder-case must1 in condensing high-pressure steam1 use #bd bushels of coal in twenty-four hours4 ,boulton and ,watt's case for a #fc-;inch cylinder working with low-pressure steam1 condensed only #d-a_/b bushels of coal in equal time1 the proportions of surface being as #aij to #bdj in ,wheal ,towan4 ,nearly five times the quantity was condensed of high steam than of low steam1 proving that there is a theory yet unaccounted for4#agj ,footnote #agj3 ,see ,trevithick's letter1 ,january #bdth1 #ahbi1 vol4 ii41 p4 #cfh4 ,these apparent facts are1 in the case of steamboats1 more culpably overlooked now than when he wrote forty-two years ago2 engines have been examined and reported on by eminent scientific men1 but it was left for ,trevithick to point out that cold on the surface of the steam-case of a ,watt low-pressure steam vacuum engine condensed about one-fifteenth of the steam given from the boilers1 and that the loss from exposure to cold was nearly five times more from high-pressure steam than from low-pressure4 ,within a few more months he determined on constructing an engine for the purpose of more accurately testing those views4 ,,mr4 ,,gilbert1 ,,hayle ,,foundry1 ,july #bgth1 #ahbi4 ,sir1--,below you have a sketch of the engine that ,i am making here for the express purpose of experimenting on the working the same steam and water over and over again1 heating the returned steam by passing it in small streams up through the hot water from the bottom of the boiler4 ,the boiler is #c feet in diameter1 standing perpendicular2 the interior fire-tube is #b feet in diameter2 there is a steam-case round the outside of the boiler with a #a-a_/b-;inch space4 ,this keeps the boiler hot and partially condenses the steam before it is again forced into the boiler4 ,illustration ,the boiler is #ae feet high2 the cylinder #ad inches diameter1 with a #f-;feet stroke1 single power4 ,the pump for forcing the steam and water back again is #aj inches in diameter1 with a #b feet #i inch stroke1 about one-quarter part of the content of the steam-cylinder4 ,the bottom of the boiler will have a great number of small holes1 about #a_/afth of an inch in diameter1 through which the steam delivered into the boiler will pass up through the hot water1 by which ,i should think it will heat those small streams of steam again to their usual temperature4 ,the pump for lifting water to prove the duty of the engine is #cj inches in diameter1 with a #f-;feet stroke1 but this may be lengthened to a #ab-;feet lift1 as the trial or load in the experiments may require1 giving from #ab to #bd lbs4 to the inch in the piston4 ,this machine will be ready before your return to ,cornwall1 and ,i intend to prove it effectually before ,i go to ,holland4 ,the ,holland engine lifted on the trial1 when they came down to see it1 #gbjj gallons of water a minute #aj feet high with #a bushel of coal an hour2 exceedingly good duty for a small engine of #bd-;inch cylinder1 being #cd1efj1jjj of duty4 ,on the #agth ,august the trial comes on between the two companies about the quays4 ,they are as desperate as possible on both sides1 and castings and every other article are thrown down to #cj per cent4 below cost price2 iron pumps for #fs4 #f;d4 per cwt41 and coal sold to the mines for #cgs4 #c;d4 per wey1 when #dhs4 per wey on board ship was paid for it4 ,several thousands lost per year by each party4 ,this never can last long4 ,if you can think of any improvement ,i shall be very glad to hear in time1 before it may be too late to adopt it4 ,at all events1 if it is not too much trouble to write1 ,i shall be very glad to hear from you4 ,what effect do you think the water will have in heating the steam on its passage to the top of the water from the false bottom of the boiler8 ,i have a cistern of cold water1 with a proper condenser in it1 connected between the bottom of the boiler-case and the force-pump to the bottom of the boiler1 therefore ,i can partially condense by cold water sides1 or by cold air sides just as ,i please1 by rising or sinking the water in the cistern4 ,the boiler is made very strong to try different temperatures1 and an additional length to the water-pump makes all very suitable for a great number of experiments1 and if there is any good in the thing ,i will bring it out4 ,i shall have indicators at different places to prove what advantages can be gained4 ,i hope to have the pleasure of your company during those experiments1 which ,i think will throw more light on this subject than ever has yet been done4 ,some trials since ,i last wrote to you make me very confident that much good will arise from these experiments1 but to what extent is uncertain4 ,i remain1 ,sir1 ,your most obedient servant1 ,,richard ,,trevithick4 ,trevithick did not use letters to illustrate his sketch1 knowing that ,davies ,gilbert would comprehend it2 but the reader of to-day may not find it so easy1 therefore the writer has added them with a slight detail description1 he having been ,trevithick's daily companion when those drawings and experiments were made4 a1 top of boiler2 b1 water line2 c1 centre of wheel2 d1 cast-iron wheel and chain2 e1 chimney1 #ac in4 in diameter2 f1 fire-tube1 #b ft4 diameter2 g1 outer boiler-99case1 #c ft4 diameter1 #ae ft4 long2 h1 water space of #f in42 i1 boiler steam-case1 #c ft4 #d in4 diameter2 j1 small holes through which steam and water are forced into the boiler2 k1 force-pump1 #aj in4 diameter1 #b ft4 #i in4 stroke2 l1 steam-cylinder1 #ad in4 diameter1 #f-;ft4 stroke2 m1 piston-rod2 n1 fire-door2 o1 fire-bars2 p1 pump for testing the power of the engine4 ,there is a natural tendency in men of genius to unwittingly return1 under new forms1 to old ideas4 ,the ideas are similar1 though in combination with new forms and new acquirements2 even the outline of this #ahbh boiler1 with the exception of its outer steam-casing1 is very like that in a letter to ,davies ,gilbert fourteen years before1#aga of which ,trevithick had kept no copy4 ,when in the foregoing letter he wrote1 ,there is a steam-case round the outside with a #a-a_/b-;inch space2 this keeps the boiler hot and partially condenses the steam before it is again forced into the boiler1 he had forgotten that twenty-seven years before1 when constructing his first high-pressure steam-engines1 he thus specified his invention3--,the steam which escapes in this engine is made to circulate in the case round the boiler1 where it prevents the external atmosphere from affecting the temperature of the included water1 and affords by its partial condensation a supply for the boiler itself4#agb ,footnote #aga3 ,see ,trevithick's letter1 #gth ,may1 #ahae1 vol4 i41 p4 #cfd4 ,footnote #agb3 ,see patent specification of #ahjb1 vol4 i41 p4 #abh4 ,not one of his numerous patent specifications has been found among his papers1 neither do his letters refer to them2 probably he never read them after the first necessary examinations4 ,,mr4 ,,gilbert1 ,,hayle ,,foundry1 ,november #eth1 #ahbi4 ,sir1--,the engine has been worked4 ,the result is ten strokes per minute1 #f-;feet stroke1 with half a bushel of coal per hour1 lifting six thousand pounds weight4 ,this was done with water in the cistern round the condenser1 which water came up to #ahj degrees of heat1 and remained so4 ,the water sides of the condenser covered with this hot water was #ej surface feet4 ,i tried it to work with the cold air sides1 but ,i found that the cold air sides of #abj feet would only work it four strokes per minute4 ,i should have worked the steam much higher than #ej lbs4 to the inch1 but being an old boiler ,i thought it a risk4 ,i am now placing an old boiler of #cej feet of cold sides more to the condenser1 to give a fair trial to condensing with cold sides alone4 ,the steam below the piston was about #f or #g lbs4 to the inch above the atmosphere4 ,the force-pump to the boiler was about one-fifth part of the content of the cylinder1 and the valve close to the boiler lifted when the force-piston was down about two-thirds of its stroke1 at which time the returned steam entered the boiler again4 ,i have no doubt of doing near ten times the duty that is now done on board ships1 without using salt water in the boiler1 as at present4 ,our boiler has been working three days and the water has not sunk #a inch per day4 ,i am quite satisfied the trial will be a great success4 ,mr4 ,praed and ,sir ,john ,st4 ,aubyn are anxious to get a high bank carried out from ,chapel ,angel to #ae feet below low-water mark on the bar1 to make ,hayle a floating harbour4 ,i have proposed to make a sand-lifting engine4 ,when ,i built that engine for deepening ,woolwich ,harbour1 we lifted #cjj tons per hour through #cf feet of water1 and #bj feet above water1 #ef feet above the bottom4 ,this was done with two bushels of coal per hour1 therefore it will not cost above one penny per square fathom to lift the sand over this embankment4 ,it is intended to get down ,mr4 ,telford to give his opinion on it4 ,your remarks on it would be of service4 ,i remain1 ,sir1 ,your humble servant1 ,,richard ,,trevithick4 ,the writer having worked at these experiments1 knows that their object was to employ high-pressure steam in the boiler1 using it very expansively in the cylinder1 and by cold surface sides reducing its bulk either to low-pressure steam or boiling water1 and then force it again into the boiler4 ,,mr4 ,,gilbert1 ,,hayle ,,foundry1 ,november #adth1 #ahbi4 ,sir1--,i have both of your letters and sketches1 which shall be put in hand4 ,i understand it perfectly well4 ,since ,i wrote to you last ,i have made several satisfactory trials of the engine1 and think it unnecessary to make any further experiments4 ,the statement below may be depended on for a future data4 ,the load of the engine was #fbhj lbs41 being #bj lbs4 to the inch for a #bj-;inch cylinder with a #f-;feet stroke1 #ab strokes per minute1 with three-quarters of a bushel of coals per hour1 giving a duty of #cfa1gbh1jjj for #a bushel of coal1 a duty far beyond anything done in the county by so small an engine4 ,the cold water sides round the condenser was #fj feet1 and the water at #aab degrees temperature1 not having a sufficient stream of cold water to supply the cistern4 ,each foot of cold water sides did #gecf lbs4 per minute1 about three times the work done in the county per foot of hot boiler sides2 therefore the condenser need not be more than one-third of the boiler sides4 ,by making the condenser of #d-;inch copper tubes and of an inch thick1 it would stand in one-twentieth part of the space of the boiler4 ,i put a boiler naked to try cold air sides2 it was very rusty1 and did not condense as fast as ,i expected4 ,the engine worked exceedingly well1 but slow4 ,the duty performed for each foot of cold air sides was #efe lbs4 per minute1 about one-thirteenth part of the condensing of cold water sides4 ,we never wanted to get the steam above #fj lbs4 to the inch4 ,i have no doubt but that copper pipes of #a_/cbnd of an inch thick1 clean and small1 would do considerably more1 because the hot water that came out of the boiler from the condensed steam was but #agj decrees1 and the external sides the same heat when the steam was #ae lbs4 above the atmosphere in the condensing boiler4 ,this boiler was #d feet #f inches diameter1 and ,i think that towards the external sides of the boiler there was a colder atmosphere1 if ,i may call it so1 than what it was in the middle of this large condensing boiler1 because ,i found by trying a small tin tube1 that it would condense #aejj lbs4 for each foot of cold air sides4 ,however1 as it is1 it will do exceedingly well for portable purposes4 ,the duty1 ,i doubt not1 will be1 both for water and air sides condensing1 at least #ej per cent4 above our ,cornish engines1 which will be above four times what is now done with ships' engines1 especially when you take into consideration their getting steam from salt water1 and letting out so much water from the boiler to prevent the salt from accumulating in the boiler1 which will make #cj per cent4 more in its favour4 ,if strong boilers to stand #bjj lbs4 to the inch are made with small tubes1 ,i have no doubt but that the duty would be considerably more1 and my engines will not be one-quarter part of the weight1 price1 or space of others2 and when every advantage is taken it will be #ajjj per cent4 superior in saving of coal to those now at work on board4 ,this engine works well1 and returns the steam very regularly every stroke into the boiler4 ,i am extremely sorry you were not present to see these experiments4 ,please make your remarks on these statements1 with any further information you may judge useful4 ,i shall now make drawings agreeable to my experiments for actual performance on board ships4 ,in hope of hearing from you soon1 ,i remain1 ,sir1 ,your very humble servant1 ,,richd4 ,,trevithick4 ,the large old boilers used as surface condensers1 in which the steam was partially condensed by the transmission of heat to the external atmosphere1 together with its further condensation in a smaller condenser with cold water around it1 so reduced its expansiveness1 that a large feed-pump drew the hot water and steam from the small condenser1 and forced it back into the boiler without any reduction of quantity2 those temporary contrivances1 almost immediately resolved themselves into a condenser made of copper tubes surrounded by cold water4 ,having proved by six months' experiment on a working scale the practicability of the plan which in reality he had invented twenty years before in the iron steamship1#agc he wrote in ,june1 #ahcj3-- ,footnote #agc3 ,drawing of iron steamship1 vol4 i41 p4 #ccf4 ,,to ,,the ,,right ,,honourable ,,the ,,lords ,,commissioners ,,of ,,the ,,admiralty1 c41 c41 c4 ,,my ,,lords1 ,about one year since ,i had the honour of attending your honourable ,board with proposed plans for the improvement of steam navigation1 and as you expressed a wish to see it accomplished1 ,i immediately made an engine of considerable power for the express purpose of proving by practice what ,i then advanced in theory4 ,i humbly request your lordships will grant me the loan of a vessel of about #bjj or #cjj tons burthen1 in which ,i will fix at my own expense and risk an engine of suitable power to propel the same at the speed required3 no alterations whatever in the vessel will be necessary4 ,when under sail the propelling apparatus can be removed1 and when propelled by steam alone1 the apparatus outside the ship will scarcely receive any shock from a heavy sea4 ,this new invention entirely removes the great objection of feeding the boiler with salt water4 ,this petition was backed by ,mr4 ,gilbert and ,mr4 ,george ,rennie4 ,his old friend ,mr4 ,mills took an interest in it1 and wrote1 ,i am going to meet ,captain ,symonds at ,woolwich again to-morrow1 and hope to be able to persuade him to use his influence with ,sir ,t4 ,hardy1 ,,lauderdale ,,house1 ,,highgate1 ,,mr4 ,,gilbert1 ,august #aith1 #ahcj4 ,sir1--,the boiler with the fire-place1 cold air tubes outside the boiler but within the steam-case1 fire-tubes in the boiler from the top of the fire-place to the top of the boiler1 the ash-pit close1 except a small door to clear out the ashes4 ,illustration3 ,,fig4 #a4--,,plan ,,section4 ,illustration3 ,,fig4 #b4--;,,elevation ,,section4#agd ,footnote #agd3 a1 steam-case2 b1 boiler-case2 c1 space for condensation of steam2 d1 water and steam space2 e1 fire-tubes2 f1 fire-box2 g1 fire-door2 h1 fire-bars2 i1 ash-box2 j1 ash-box door2 k1 air-tubes in condenser2 l1 chimney2 m1 water level2 a smoke-jack fan draught4 ,the design is for the cold air to pass down from the top of the boiler through the air-tubes within the steam-case surrounding the boilers1 becoming heated in its passage by condensing the steam in the case1 and then to pass up through the fire-bars in1 the hot state1 nearly as hot as the steam in the case2 because this air1 heated to nearly #bab degrees by condensing the steam in its passage without any of its oxygen being burnt1 it will not carry off so much heat from the fire as cold air would1 and still have the same oxygen as cold air to consume the coal4 ,the cold air will be passing down the steam-case in the air-tubes1 and up through the fire and fire-tubes in the boiler4 ,i find by experiments ,i have made here1 by placing a tin tube #b-a_/b inches in diameter1 #d feet long1 inside a #d-;inch tube of the same length1 having boiling water and steam between the tubes1 kept hot by a fire round the outer tube1 with a smith's bellows blowing in at the bottom of the inside tube1 having #b-b_/crds surface feet of condensing sides1 measuring the inside1 where the air is passing up from the bellows1 heats from #fj to #acd degrees #ae square feet of cold air per minute4 ,when you compare the effective heat of #gd degrees given to #ae cubic feet of air every minute from #b-b_/crds surface feet of tin plate1 and the heat contained in #ae cubic feet of air charged with #gd degrees of effective heat1 compared with steam of atmosphere strong1 you will find that the condensing power of surface sides is very great1 and for locomotive purposes might be carried still further1 by forcing the air more quickly through the tubes4 ,if the statements on air given in some books that ,i have read are correct1 that there is about three times as much heat in #a gallon of steam of atmosphere strong as there is in #a gallon of air of #bab degrees of heat1 in that case #a surface foot of tin-plate sides of this pipe1 by sending off the hot air before described1 would take out the heat of #a-a_/b cubic foot of steam per minute of atmosphere strong1 which in the common condensing engine would be equal to a duty of #bgjj lbs4 lifted #a foot high per minute2 but in the high-pressure expansive engine1 the heat of #a-a_/b cubic foot of steam would give a duty of #aj1hjj lbs41 or four times the duty of the ,boulton and ,watt engine4 ,if you calculate on the air being heated to nearly #bab degrees before it enters the fire1 together with the heat given to the sides of the boiler1 the fuel saved will be above one-half on what has been done by the high-pressure engines in ,cornwall1 because at present the coal must pay for heating the cold air1 therefore a less proportion goes through the sides of the boiler1 and is lost through the chimney2 whereas if the heat of the steam1 by passing into the cold air1 on its way through the condenser tubes1 is carried into the fire-place1 one-half of the coal must be saved2 and you will find by calculation that the quantity of air required to burn the coal1 and also to condense the steam1 goes exactly in proper proportion for each other1 and for locomotive engines with a blast will go hand-in-hand almost to any extent1 and the size of an engine1 for its power1 is a mere nothing4 ,a smoke-jack fan in the ash-pit under the fire-bars1 worked by the engine1 would draw air down the condensing tubes1 and force it up through the fire and fire-tubes always with the speed required1 as the steam and the condensation would increase in the same ratio4 ,as it is possible to blow so much cold air into a fire as to put it out1 by first heating the air it would burn all the stronger1 and whatever heat is taken out of the condenser into the fire-place from the steam that has been made use of1 half this extra heat will go into the boiler again1 or in other words1 but half the quantity of cold will be put into the fire1 being the same in effect as saving fuel4 ,taking heat from the condenser through the boiler sides is an additional new principle in this engine4 ,i find by blowing through tubes that the condensation of a surface foot of air-tube against a surface foot of boiler fire-tube is greater than the fire that passes through the boiler sides1 where the common chimney draught is used1 by nearly double2 but ,i expect when both air and fire tubes are forced by a strong current of air it will be nearly equal1 and the increase of steam and of condensation can be increased by an increased current of air1 so as to cause a surface foot of fire and of air sides to do perhaps five times as much2 and of course the machine will be lighter in proportion4 ,i think air sides condensation preferable to water sides1 as so small a space does the work1 and is always convenient1 and its power uniformly increasing with its speed1 by the increased quantity of air1 without the weight of water vessels4 ,this kind of engine can be made to suit every place and purpose1 and ,i think such an engine of the weight of a ,boulton and ,watt engine will perform twenty times the duty4 ,air sides condensation will be advantageous on board ship1 because there are holes for the passage of water through the bottom and sides of the ship4 ,i am anxious to have your opinion on this plan of returning the hot air from the condenser to the fire-place1 and what you think the effect will be4 ,the ,comptroller of the ,navy has not yet returned from ,plymouth1 therefore no answer has been given to me4 ,you will see by the sketch how very small and compact an engine is now brought without complication or difficulty2 each surface foot of boiler and condenser is equal to one-third of a horse-power1 weighing #bj lbs41 or #fj lbs4 weight for each horse-power4 ,the consumption of fuel is so small when working a differential engine1 that ,i expect it will not exceed #a lb4 of coal per hour for each horse-power4 ,the cost of erection and required room are so small from its simplicity that it will be generally used4 ,as ,i am very anxious that every possible improvement should be considered prior to making a specification for a patent1 ,i must beg that you will have the goodness to consider and calculate on the data ,i have given you4 ,i am sorry to trouble you1 but ,i am satisfied this will be to you rather a pleasing amusement than a trouble4 ,the warming machines will take a very extensive run1 and ,i believe will pay exceedingly well4 ,i am almost in the mind to take a ride down to see you in a few days1 but am now detained here about the ,american mining concerns4 ,i remain1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,the letters and foot-note are the only changes made by the writer in ,trevithick's original sketch so descriptive of a wonderful application of varied and improved principles of long-known difficulty and importance2 the beautifully compact tubular boiler for giving high-pressure superheated steam1 surface condensation1 absence of feed and condensing water1 and return of the heat1 in other engines wasted in condensation1 to the fire-place2 though there is little or no mention of the mechanical or moving parts of the steam-engine1 yet its vital principles are grasped with the hand of a master4 ,the sketch in the letter hastily made forty years ago is more ingenious than any portable engine since constructed1 though there may be no sufficient proof of its practical success4 ,the propeller to be worked by this novel engine was of course his long-idle screw4 ,steam ,engines1 #bast ,february1 #ahca4 ,,now ,,know ,,ye1 that in compliance with the said proviso1 ,i1 the said ,richard ,trevithick1 do declare that the essential points in my improved steam-engine1 for which ,i claim to be the first and true inventor1 are3-- ,firstly1 the placing of the boiler within the condenser1 in order to obtain the additional security of the strength of the condenser to prevent mischief in case the boiler should burst1 and also by the same arrangement to conveniently make the condenser1 with a very extensive surface1 enabling me to condense the steam without injecting water into it4 ,secondly1 the enclosing of the condenser in an air or water vessel1 by which the intention of safety from explosion is further provided for1 and my engine really rendered what ,i denominate it1 a high-pressure safety engine4 ,thirdly1 the condensing of the steam in the condenser by means of a current of cold air or cold water forced against the outsides of the condenser4 ,fourthly1 the returning of the condensed steam from the condenser back again into the boiler1 to the end that sediment and concretion in the boiler may be prevented2 and1 ,fifthly1 the blowing of the fire with the air after it has been heated by condensing the steam4 ,in forming my improved steam-engine ,i employ several or all of these points according to convenience1 in combination with the other necessary parts of steam-engines in common use4 ,these1 my essential points1 will admit of various modifications as to form and proportions such as must be and are quite familiar to every competent steam-engine manufacturer1 and therefore it will be sufficient for the perfect description of my improved steam-engine that ,i explain some of the modes of forming and combining the essential points of my invention with the other parts of steam-engines in common use4 ,in my most favourite form of engine in which ,i condense by a current of cold air1 the fire-place and flue1 the boiler1 the condenser1 and the air-vessel1 are made of six concentric tubes1 standing in an upright position4 ,the inner or first tube forms the fire-place and flue1 and at the same time the inner side of the boiler4 ,this tube is conical1 having its small end upwards4 ,the next or second tube is cylindrical1 about #f inches larger in diameter than the lower end of the first tube1 and forms the outside of the boiler1 leaving a space all round of about #c inches at the bottom1 and so much more at the top1 as the flue is taper for holding water and steam between the two tubes4 ,the third tube is about #b inches larger in diameter than the second1 in order to allow a space of about an inch for powdered charcoal or some other slow conductor of heat4 ,this tube also constitutes the inner side of the air-vessel4 ,the fourth tube is about #b inches larger than the third1 and forms the inner side of the condenser4 ,the fifth tube1 about #b inches larger than the fourth1 forms the outside of the condenser2 and the sixth tube1 about #b inches larger than the fifth1 forms the outside of the air-vessel1 and at the same time the outside of the whole of the generating and condensing apparatus1 consisting of fire-place1 flue1 boiler1 condenser1 and air-vessel4 ,these tubes are made of wrought-iron plates riveted together1 and are all cylindrical1 except the first1 which is conical1 the bottom or fire end being the largest4 ,the first or inner tube is closed at bottom1 but has an opening on one side near the bottom1 through which the fire-bars are introduced1 and the ashes and clinkers taken away4 ,to this opening a neck-piece about #c inches long is riveted1 having a flange to fit against the inside of the second tube1 when the two tubes are concentric1 through1 the side of which second tube is an opening corresponding with that in the first tube1 and the flanch is screwed to the second tube so as to make one opening through the sides of the two tubes4 ,the second tube extends downwards about #e inches below the first tube1 and has a flanch turning inwards1 to which a second round plate of iron is screwed1 forming the bottom of the boiler4 ,the first tube has an external flanch at the top1 and the second tube an internal flanch1 both of the same height1 and screwed to a cast-iron circular plate or cap-piece1 which extends wide enough around the boiler to form also the cover for the air-vessel4 ,this plate has a hole in the middle as large as the flue4 ,the sides of the condenser and air-vessel are formed of four concentric tubes1 each about #b inches larger than the one within it4 ,the inner and outer of these tubes constitute the sides of the air-vessel1 and are each furnished with an external flanch at the top by which they are screwed to the cap-piece4 ,the two intermediate tubes constituting the sides of the condenser are riveted together at the top1 leaving a space of about an inch between their upper ends and the cap-piece1 so as to allow of a free communication over them between the outer and inner parts of the air-vessel4 ,the inner tube of the air-vessel extends downwards about an inch below the boiler1 and is closed by a flat plate screwed on to a flanch projecting inwards from the tube2 the two tubes of the condenser descend about #c inches lower than the boiler4 ,the inner tube has an internal flanch1 to which a flat circular plate is screwed to close up the tube4 ,the outer tube of the condenser is of the same length with the inner1 and is provided with an external flanch about #c inches broad4 ,the outer tube of the air-vessel has an external flanch #b inches broad1 and is just long enough to come down upon the broad flanch of the condenser last described1 and these two flanches are together bolted upon a bottom piece of cast iron1 which is a dish of #d inches deep1 and equal in diameter with the diameter of the outer tube1 and having a flanch the same breadth as the flanch of the outer tube1 and the bottom piece is secured to the air-vessel and outer tube of the condenser by bolts going through all the three flanches4 ,an opening is made through the sides of all the four tubes of the condenser and air-vessel opposite to and as wide as the fire-place opening through the sides of the boiler4 ,the upper part of both openings to be of the same height1 but the outer opening is made as low as the bottom of the boiler1 in order to allow room for a pipe to enter that part of the boiler for forcing the water into it1 and also another pipe and cock for drawing off the water or sediment1 in case foul water be used by accident or carelessness4 ,these two openings through the condenser and air-vessel1 and through the boiler1 constitute one fire doorway through all the six tubes for access to the fire-place2 a ring is placed between the two tubes of the condenser around the fire doorway1 so as to cut off all communication of the steam in the condenser with the air in the doorway2 another similar ring is placed between the condenser and the outer tube to prevent the escape of air into the fire doorway1 and a half ring is placed in the lower part of the fire doorway between the condenser and the inner tube of the air-vessel1 to prevent ashes from falling into the air-vessel1 and yet allow a free passage for the air from the inner part of the air-vessel into the upper part of the fire doorway4 ,these two rings and the half ring are secured in their places by rivets passing through all of them and through the tubes1 and uniting all firmly together1 the interstices being filled with iron cement4 ,a ring is also placed between the boiler and the air-vessel around the fire doorway1 against the outside of which ring the charcoal powder is tightly rammed1 and will hold the ring in its place without the necessity of either rivets or screws4 ,that part of the fire doorway which is above the fire-bars is supplied with an inner door1 to shut the fire-place even with the outside of the boiler1 and exclude all access of air to the fire1 except through the grating4 ,the whole of the fire doorway is enclosed by an outer door even with the outside of the air-vessel1 to exclude all air1 except that which comes through the air-vessel2 a pipe is fixed in the bottom or dish-piece leading to a forcing pump to draw the water out of the condenser and force it into the bottom of the boiler through the pipe before described4 ,a blowing cylinder of about ten times the content of the main cylinder is screwed against the outside of the air-vessel1 and opposite to the two outlet valves of the blowing cylinder two apertures are made in the air-vessel1 through which the air is forced in4 ,the main cylinder of the engine1 of the usual dimensions according to power wanted1 is also screwed against the outside of the air-vessel high enough above the blowing cylinder to allow room for the main-crank shaft to work between them4 ,the forcing pump before mentioned is also screwed to the outside of the air-vessel1 and thus my improved steam-engine becomes more compact and convenient than any preceding steam-engine4 ,for the purpose of supplying the boiler with distilled water1 in case there should be a deficiency in it1 a small vessel made of two upright tubes1 one within the other1 is placed on the cap-piece4 ,the inner tube is of the same diameter as the flue1 and forms a continuation of it4 ,the outer tube is about #f inches larger than the inner1 and the space at the top and bottom between the two tubes is closed by two ring-shaped pieces4 ,this vessel may be about #ah inches high2 a cock is fixed in the top of this vessel1 to which a bent pipe is fastened1 leading to and united with a pipe which arises from the top of the condenser and passes through a hole in the cap-piece1 and thus a communication between the supplying vessel and the condenser may be opened or shut at pleasure2 another pipe1 also furnished with a stop-cock1 arises from the vessel1 and communicates with a water-cistern to receive its supply of water when required2 a third pipe1 having a cock in it1 opens into the vessel near the bottom to let out the sediment2 a small cock to let the air out is also fixed in the top of the vessel1 which cock may also be used for letting air out of the condenser4 ,in order to supply the boiler with water by means of this vessel1 the stop-cock leading to the condenser is shut1 and that leading to the cistern is opened1 and at the same time the air-cock is opened to allow the air to escape that the water may fill the vessel4 ,when the vessel is nearly full of water1 the air-cock and the cock from the cistern are shut1 and that in the pipe leading to the condenser is opened4 ,the water being then heated by the flue is converted into steam1 which1 passing into the condenser1 is there reduced to water again1 leaving the sediment or salt in the supplying vessel1 which sediment or salt may be occasionally blown out through the bottom pipe by filling the vessel with1 water1 shutting the water1 steam1 and air cocks1 and opening the cock of the outlet pipe at a time when the steam in the vessel is strong4 ,but the supply of water from the condenser being always equal to that converted into steam and used in the engine1 there is no tendency to a variation in the height of the water in the boiler1 except there be leakage or waste of steam in some part of the engine4 ,an upright glass tube1 having an iron tube of communication with the lower part of the boiler and another iron tube of communication to the upper part of the boiler1 is conveniently placed against the outside of the air-vessel to indicate at all times the height of the water in the boiler2 as is usual in steam-boilers1 a valve is placed on the top of the air-vessel to allow of the escape of a portion of the air in case that the quality of the fuel should not require so much air for perfect combustion as the steam requires for good condensation4 ,the degree of the condensation of the steam may be increased at pleasure1 by increasing the velocity of the air passing into and through the air-vessel4 ,the other parts of my improved steam-engine1 such as the steam-pipes1 the throttle-valve1 the safety-valve1 the vacuum-valve1 the working valves1 crank1 connecting rods1 cross-heads1 pistons1 piston-rods1 and various other minor parts common to engines in general use may be made in the usual forms1 and placed in the most convenient situations2 they cannot1 therefore1 need any description4 ,when it is intended to use water for condensing instead of air1 my improved steam-engine must be made as before directed1 except that the communication between the air-vessel and the fire-place must be closed1 which may be done by a perfect ring of iron surrounding the opening leading to the fire-place1 instead of the half ring before described1 and a forcing pump must be employed to draw water from a reservoir1 and force it into the vessel which ,i have hereinbefore denominated the air-vessel1 but which in this mode of working would more properly bear the name of water-vessel4 ,in this case a blowing cylinder1 the dimensions of which must be calculated according to the quality of the fuel to be used1 may be worked to blow the fire through a pipe leading into the ash-pit4 ,this1 however1 will not be necessary where there is a chimney high enough to create a strong draught4 ,in respect to proportions1 my improved steam-engine admits of considerable latitude1 and it will be sufficient direction to any practical engineer to say that for engines working with steam of #abj lbs4 to the inch1 used expansively till it be nearly reduced to atmospheric strength and then condensed1 a #aj-;horse engine may have a fire-place of #bj inches diameter1 the flue at the top #aj inches diameter1 and a boiler of #bj feet high2 a #fj-;horse engine1 a fire-place of #cf inches diameter1 a flue of #af inches diameter1 and a boiler of #bj feet high4 ,in boat-engines1 and in other cases where height cannot be allowed1 the diameter must be increased4 ,the thickness of the two tubes constituting the boiler sides of a #aj-;horse engine may be #a_/hth of an inch1 that of a #fj-;horse a quarter of an inch1 and so in proportion for engines of other power4 ,the tubes constituting the condenser and inner tube of the air-vessel may in all cases be #a_/hth of an inch thick4 ,the outer tube may be #c_/hths of an inch thick1 to afford stability to the working cylinder1 the blowing cylinder1 and the forcing pump fastened to this tube1 and as an ultimate perfect barrier against explosion4 ,the respective distances of the other tubes constituting the outside of the boiler1 the condenser1 and air-vessel1 will be the same as hereinbefore given1 and therefore their diameters will depend upon the diameter of the fire-place4 ,the cap-piece in small engines may be half an inch thick1 and in large engines an inch4 ,the bottom of the ash-pit and bottom of the boiler must have about half an inch of thickness for every foot diameter1 or they may be cast with ribs to afford equivalent strength4 ,the fuel is supplied through a door in the flue1 at the top of the boiler1 consisting of coke or coals the least liable to swell with heat4 ,the flue may be filled to about one-third of the height of the boiler1 and the water fill about three-fourths of the boiler1 leaving one-fourth for steam4 ,having clearly explained my improved steam-engine so that any person competent to make a steam-engine can from this description understand my invention and carry the same into effect in as beneficial a manner as myself1 ,i proceed to observe that the extreme safety of my improved steam-engine will be seen1 from considering that in case the boiler should explode inwards into the flue1 the power of the steam would be first reduced by filling the flue and fire-place1 and could not escape through the chimney and fire doorway faster than it would diffuse itself and be condensed by mixing with the surrounding air1 and thus lose all its force4 ,but should the outside of the boiler burst1 part of the force of the steam would be spent in filling up the interstices between the particles of the charcoal1 and would then probably be too weak to effect a breach through the inner tube of the air-vessel2 and should such a second breach be effected1 the space within the air-vessel would allow the steam to expand and partly condense1 and a portion to escape into and through the fire doorway1 where it would divide itself1 and proceed harmlessly up the flue1 and out at the doorway2 so that the outer case being a reserve of strength1 would to a certainty withstand the force remaining in the steam after the before-mentioned successive reductions of power4 ,the patent of ,february1 #ahca1 perfects the sketch in his letter of ,july #bgth1 #ahbi1 which in its turn made more perfect the plans put into practice in #ahae1 just before leaving ,england for ,america4#age ,the prejudice against the use of his high-pressure steam-engine he tried to meet by calling it a high-pressure safety engine4 ,the boiler was of six wrought-iron upright tubes1 one within the other4 ,the inner one was the fire-tube1 surrounded by a tube of larger diameter1 forming the water and steam space4 ,this was again surrounded by another tube1 #b inches larger in diameter1 the space being filled with charcoal or other non-conductor of heat2 another tube1 #b inches more in diameter1 formed the inner circle of the condenser1 having an inch space for the passage of cold air from the blowing cylinder1 carrying the heat from the condensing steam back to the fire-place4 ,still another tube1 #b inches more in diameter1 giving a space into which the used steam from the cylinder passed to be condensed4 ,then came the outside tube1 #b inches more in diameter1 forming a second space for the passage of air1 taking heat from the condenser into the fire4 ,the steam-boiler had its heat retained by a coating of charcoal2 next to it came a current of cold air an inch thick1 carrying back to the fire any heat that had passed through the charcoal coat1 and also the heat from the inner surface of the condenser4 ,then came the inch-thick circle of steam1 on its exit from the cylinder1 to be condensed2 and finally an outside circle of cold air1 performing the same functions as the inner circle in condensing the steam and carrying its heat back again to the fire4 ,footnote #age3 ,see ,trevithick's letters1 ,july #hth1 #ahae1 vol4 ii41 p4 #hj1 and #gth1 vol4 i41 p4 #cfd2 and #afth ,may1 vol4 i41 p4 #cgj2 and patent of #ahae1 vol4 i41 p4 #cge4 ,the object or principle of this engine was to avoid the loss of heat1 and the necessity for either condensing water or feed-water1 as described in the letter and drawing of ,august #aith1 #ahcj1 but the detail was changed1 mainly to facilitate construction4 ,as in practice it might be impossible to fully attain those objects1 preparation was made to get rid of the salt from such water as might be required as feed-water to make good the loss from leakage or other defects in the working of marine steam-engines4 ,the specification states3 ,for the purpose of supplying the boiler with distilled water1 in case there should be a deficiency in it1 a small vessel made of two upright tubes1 one within the other1 is placed on the cap-piece4 ,the inner tube is of the same diameter as the flue1 and forms a continuation of it4 ,the water being heated by the flue is converted into steam1 which1 passing into the condenser1 is there reduced to water again1 leaving the sediment or salt in the supplying vessel4 ,where water condensation was preferred the surface-air condenser could be converted into a surface-water condenser by a current of cold water in place of the air2 in which case the air from the blowing cylinder was taken direct in to the fire-place or other means used for giving the necessary draught4 ,steam of about #ace lbs4 to the inch was to be so expansively worked as at the finish of the stroke1 on its escape to the condenser1 to be no more than atmospheric pressure1 or #ae lbs4 to the inch--just the strength with which ,watt preferred to commence his work in the cylinder4 ,the most prominent feature in ,trevithick's numerous modifications of the steam-engine was the boiler4 ,in the ',life of ,watt1' though his commentators have been numerous and eminent1 little or nothing is said about the boiler or the steam pressure4 ,he left that all-important part of the steam-engine just as he found it1 resisting the increase of steam pressure1 which was the mainspring of ,trevithick's engine4 ,the boiler of the high-pressure engines of #agifagf sheltered the steam-cylinder from cold2 and the used steam from the cylinder circulated around the exterior of the boiler1 on its way to the blast-pipe1 while the condensed portion was returned as feed-water in the patent engine of #ahjb4agg ,in #ahaa he proposed to force air into the fire-place1 hoping thereby to reduce the amount of heat lost by the chimney4#agh ,his various forms of tubular boilers1 as at the ,herland ,mine1#agi and at ,dolcoath1#ahj and the upright multitubular boilers patented in #ahae4aha followed up in #ahbh4 ,i shall have a small portable engine finished here next week1 and will try to heat steam independent of water1 in small tubes of iron1 on its passage from the boiler to the cylinder1 and also try cold sides for condensing4 ,in #ahbi a simple boiler and condenser composed of three tubes was made1 the inner or fire-tube being #b feet in diameter and #ae feet long1 for the express purpose of experimenting on the working the same steam and water over and over again2#ahb and on the same subject1 ,by making the condenser of #d-;inch copper tubes #a_/cbnd of an inch thick1 it would stand in one-twentieth part of the space of the boiler3#ahc and finally the sketch of the tubular boiler and tubular condenser of #ahcj1 in its boiler portion similar to the best portable boilers of the present day1 and the patent specification of #ahca4 ,surely therefore to him belongs the credit of having invented and perfected the tubular boiler and surface condenser4 ,footnote #agf3 ,see vol4 i41 p4 #ajd4 ,footnote #agg3 ,see patent specification1 vol4 i41 p4 #abh4 ,footnote #agh3 ,see ,trevithick's letter1 #acth ,jan41 #ahaa1 vol4 ii41 p4 #f4 ,footnote #agi3 ,see vol4 ii41 p4 #ga4 ,footnote #ahj3 ,see chap4 xx4 ,footnote #aha3 ,see ,trevithick's letters1 #hth ,july1 #ahae1 vol4 ii41 p4 #hj2 and #gth and #afth ,may1 vol4 i41 pp4 #cfd1 #cgj4 ,footnote #ahb3 ,see vol4 ii41 p4 #ccb4 ,footnote #ahc3 ,see vol4 ii41 p4 #ccf4 ,smiles has written3#ahd-- ,footnote #ahd3 ,see ',life of ,george ,stephenson1' by ,smiles1 p4 #bgi2 published #aheg4 ,for many years previous to this period 7#ahbi71 ingenious mechanics had been engaged in attempting to solve the problem of the best and most economical boiler for the production of high-pressure steam4 ,various improvements had been suggested and made in the ,trevithick boiler1 as it was called1 from the supposition that ,mr4 ,trevithick was its inventor4 ,but ,mr4 ,oliver ,evans1 of ,pennsylvania1 many years before employed the same kind of boiler1 and as he did not claim the invention1 the probability is that it was in use before his time4 ,the boiler in question was provided with an internal flue1 through which the heated air and flames passed1 after traversing the length of the under side of the boiler1 before entering the chimney4 ,this was the form of boiler adopted by ,mr4 ,stephenson in his ,killingworth engine1 to which he added the steam-blast with such effect4 ,we cannot do better than here quote the words of ,mr4 ,robert ,stephenson on the construction of the ',rocket' engine3--',after the opening of the ,stockton and ,darlington1 and before that of the ,liverpool and ,manchester ,railway1 my father directed his attention to various methods of increasing the evaporative power of the boiler of the locomotive engine4 ,amongst other attempts1 he introduced tubes 7as had before been done in other engines7--small tubes containing water1 by which the heating surface was materially increased4 ,two engines with such tubes were constructed for the ,st4 ,etienne ,railway1 in ,france1 which was in progress of construction in the year #ahbh2 but the expedient was not successful2 the tubes became furred with deposit1 and burned out4 ',other engines1 with boilers of a variety of construction1 were made1 all having in view the increase of the heating surface1 as it then became obvious to my father that the speed of the engine could not be increased without increasing the evaporative power of the boiler4 ,increase of surface was in some cases obtained by inserting two tubes1 each containing a separate fire1 into the boiler2 in other cases the same result was obtained by returning the same tube through the boiler2 but it was not until he was engaged in making some experiments1 during the progress of the ,liverpool and ,manchester ,railway1 in conjunction with ,mr4 ,henry ,booth1 the well-known secretary of the company1 that any decided movement in this direction was effected1 and that the present multitubular boiler assumed a practicable shape4 ,it was in conjunction with ,mr4 ,booth that my father constructed the ',rocket' engine4 ',in this instance1 as in every other important step in science or art1 various claimants have arisen for the merit of having suggested the multitubular boiler as a means of obtaining the necessary heating surface4 ,whatever may be the value of their respective claims1 the public1 useful1 and extensive application of the invention must certainly date from the experiments made at ,rainhill4 ,m4 ,seguin1 for whom engines had been made by my father some few years previously1 states that he patented a similar multitubular boiler in ,france several years before4 ,a still prior claim is made by ,mr4 ,stevens1 of ,new ,york1 who was all but a rival to ,mr4 ,fulton in the introduction of steamboats on the ,american rivers4 ,it is stated that as early as #ahjg he used the multitubular boiler4 ',these claimants may all be entitled to great and independent merit2 but certain it is1 that the perfect establishment of the success of the multitubular boiler is more immediately due to the suggestion of ,mr4 ,henry ,booth1 and to my father's practical knowledge in carrying it out4' ,we may here briefly state that the boiler of the ',rocket' was cylindrical1 with flat ends1 #f feet in length1 and #c feet #d inches in diameter4 ,the upper half of the boiler was used as a reservoir for the steam1 the lower half being filled with water4 ,through the lower part twenty-five copper tubes of #c inches diameter extended1 which were open to the fire-box at one end and to the chimney at the other4 ,the fire-box1 or furnace1 #b feet wide and #c feet high1 was attached immediately behind the boiler1 and was also surrounded with water4 ,stephenson knew of ,trevithick's patent of #ahjb1ahe in which a three-tubed boiler is shown2 and it was after that time that ,oliver ,evans and ,fulton tried their experiments1 and also the numerous engines with single or return double tube1 at work in the principal towns of ,england prior to #ahjd1ahf and near his residence in childhood and in manhood4#ahg ,footnote #ahe3 ,see vol4 i41 p4 #abh4 ,footnote #ahf3 ,see ,trevithick's letter1 ,sept4 #bcrd1 #ahjd1 vol4 ii41 p4 #b4 ,footnote #ahg3 ,mr4 ,armstrong's note1 vol4 i41 p4 #ahd4 ,george ,stephenson's ,killingworth boiler1 to which he added the steam-blast with such effect1 was a copy of ,trevithick's boiler and blast1 working since #ahjd in ,newcastle-on-,tyne1 and was precisely the boiler described by ,stephenson2 in other cases the same result was obtained by returning the same tube through the boiler4 ,this is an admission from ,stephenson that ,trevithick's patent boiler was the best in use up to about #ahbh4 ,a further proof of the indirect public gain from the use of ,trevithick's return-tube boiler over a period of thirty years is their having supplied high-pressure expansive steam in the first experiments made with such steam by the ,admiralty1 at whose request ,mr4 ,rennie and others examined the duty of the ,cornish high-pressure expansive engine1 and ,captain ,king1 ,r4,n41 in charge of the ,admiralty ,department at ,falmouth in #ahcj1 gave an order to ,harvey and ,co4 to construct high-pressure steam-boilers for the ,government vessel ',echo'2 in #ahca the machinery was put on board the ',echo' in the ,government ,dockyard at ,plymouth1 and included three of ,trevithick's return-tube boilers1 made of wrought iron1 each #e feet #f inches in diameter and #bd feet long1 with internal return fire-tube #b feet #b inches in diameter4 ,the fire-place end of the boiler was #f feet #i inches deep by #e feet #f inches wide1 to give room for the fire-place and ash-pit4 ,the steam pressure was #bj lbs4 on the inch above the atmosphere1 worked by double-beat valves1 #f inches in diameter1 with expansive gear4 ,this new machinery was fixed under the superintendence of the writer1 after which the ,government engineers took charge of the vessel1 and the writer who had1 as the mechanic in charge1 worked like a slave1 though receiving but #as4 #f;d4 a day and expenses1 was not invited to take any part in the experimental trials1 nor ever heard of the result except in the ordinary rumours of ,admiralty bungling on board the ',echo4' ,those boilers were similar to the ,trevithick boiler that had served the locomotive in ,newcastle and elsewhere from #ahja to #ahbh1 the first steamboat experiments in ,england1 in ,scotland1 and in ,america1 and the numerous high-pressure engines then at work4 ,illustration3 ,,bottle-,,neck ,,boiler4 ,the enlarging the fire-place end of boilers or fire-tubes has led to many forms4 ,trevithick's model of #agifahh had an oval tube giving a greater spread of fire-99bars2 the same is seen in the #ahjh steamboat2#ahi the ,dolcoath boilers of #ahaaaij show the oval and also the bottle-neck fire-tube2 the ,welsh locomotive of #ahjdaia had the fire-tube contracted at its bend or return portion2 the ,tredegar puddling-mill fire-tube of #ahjaaib tapered gradually from the fire-bridge to the chimney end2 in the ,london locomotive of #ahjhaic the fire-tube took the bottle-neck shape close to the fire-bridge4 ,the accompanying sketch shows the bottle-neck contraction1 only on the top and sides of the fire-tube was to give breadth to the fire-bars d1 and thickness to the fire at bridge c1 after which the flue portion of the fire-tube was contracted3 this boiler was for many years a favourite in ,cornwall4 ,the bottle-neck contraction of the ',echo' boiler was similar to the above1 except that the enlargement of the fire-place was downwards instead of upwards1 and the fire-tube1 instead of going through the end of the boiler1 returned to near the enlarged fire-place1 when it passed out through the side of the boiler to the chimney1 just as in the ,tredegar puddling-mill boiler2 all those variations were with the object of increasing the fire-grate1 and at the same time keeping down the gross size and weight of boiler and its water4 ,footnote #ahh3 ,see vol4 i41 p4 #ajd4 ,footnote #ahi3 ,see vol4 i41 p4 #cce4 ,footnote #aij3 ,see vol4 ii41 p4 #afi4 ,footnote #aia3 ,see vol4 i41 p4 #aha4 ,footnote #aib3 ,see vol4 i41 p4 #bbc4 ,footnote #aic3 ,see vol4 i41 p4 #bjg4 ,in #ahje1 ,lord ,melville failed to keep his appointment with ,trevithick1 on his proposal to construct a high-pressure steamboat4#aid ,rennie1 a pupil and friend of ,watt1 and familiar with ,trevithick's high-pressure steam-dredgers on the ,thames1 was employed by ,lord ,melville and the ,admiralty on the ,plymouth ,breakwater1 where in #ahac ,trevithick proposed the use of his high-pressure steam locomotive and boring engine4#aie ,in #ahbj ,rennie wrote to ,watt1 that the ,admiralty had at last decided upon having a steamer2 at that time fifteen years had passed since ,trevithick's offer to propel the ,admiralty by steam-puffers1 and ten years more were to pass before they could make up their minds to venture on high-pressure steam from his boilers4 ,the ,steam ,users' ,association are equally hesitating1 judging from words just spoken by an engineer1 the son of an engineer3-- ,footnote #aid3 ,see ,trevithick's letter1 #ajth ,jan41 #ahje1 vol4 i41 p4 #cbd4 ,footnote #aie3 ,ibid41 vol4 ii41 p4 #bd4 ,sir ,william ,fairbairn said he had come to the conclusion1 after many years' experience1 that it was in their power to economize the present expenditure of fuel by a system which might not be altogether in accordance with the views of the members of the association or the public at large1 and that was to increase the pressure of steam4 ,he would have great pleasure in stating a few facts which might some day tend to bring about a change1 if not a new era1 in the use of steam4 ,from the result of a series of experimental researches in which he had been engaged for several years on the density1 force1 and temperature of steam1 he had become convinced that in case we were ever to attain a large economy of fuel in the use of steam1 it must be at greatly-increased pressure1 and at a rate of expansion greatly enlarged from what it was at present4 ,already steam users had effected a saving of one-half the coal consumed by raising the pressure from #g lbs4 and #aj lbs4--the pressure at which engines were worked forty years ago--to #ej lbs41 or in some cases as high as #gj lbs4 on the square inch4#aif ,footnote #aif3 ',the ,engineer1' ,march #aeth1 #ahgb3 remarks by the ,chairman at a meeting of the ,manchester ,steam ,users' ,association4 ,dear me6 would have been ,trevithick's exclamation had he read this2 did ,i devote my whole life to the making known the advantages of high-pressure steam1 and did ,i1 seventy years ago1#aig really work expansive steam of #ade lbs4 on the inch in the presence of many of the leading engineers of the day6 ,of course this short extract of a speech made by a member of a practical society1 may not be taken as conveying fully the speaker's views1 but it illustrates the immense difficulty ,trevithick encountered in making his numerous plans acceptable to the public4 ,footnote #aig3 ,see ,trevithick's letter1 ,august #bjth1 #ahjb1 vol4 i41 p4 #aed4 ,another modern statement bearing on inventions originating with ,trevithick1 but wearing new garbs with new names1 shows the same tendency to ignore old friends1 or1 to say the least of it1 to pass them by3-- ,the trial of ,no4 #cf steam-pinnace was made at ,portsmouth yesterday4 ,her peculiarity consists in the arrangement of her propelling machinery1 in the adaptation of the outside surface condenser1 and a vertical boiler1 both patented by ,mr4 ,alexander ,crichton4 ,the condenser is simply a copper pipe passing out from the boat on one quarter at the garboard strake1 and along the side of the keel1 returning along the keel on the opposite side1 and re-entering the boat on that quarter4 ,the boiler is designed for boats fitted with condensing engines1 and which1 therefore1 are without the acceleration of draught given by the exhausted steam being discharged into the funnel4 ,it is of the vertical kind1 and stands on a shallow square tank1 which forms the hot well4 ,the tubes are horizontal over the fire1 the water circulating through them4 ,the condensed steam is pumped into the well at a temperature of #ajj1 and being there subjected to the heat radiating from the furnace1 is pumped back into the boilers at nearly boiling point4 ,it is estimated that1 under these conditions1 the pinnace would run for nearly #dh hours without having to 'blow off' or carry a supply of fresh water1 the waste water being made good by sea water4#aih ,footnote #aih3 ',the ,times1' ,november #bdth1 #ahga4 ,the peculiarity of this steam-pinnace of #ahga1 on which a patent was granted1 is stated to be a metal surface condenser exposed to the cold water at the bottom of the boat1 returning the condensed steam at about boiling temperature to the boiler1 and a vertical boiler with horizontal tubes through which the water circulates1 both of which in principle1 if not in detail1 are seen in the surface condenser of ,trevithick's iron-bottom ship of #ahji1 and his vertical boiler of #ahaf1aii and further illustrated in the inventions spoken of in this and the following chapter2 and yet on so all-important a subject1 dealt with in various ways by ,trevithick from #ahjd to #ahcb1 his plans are reproduced as discoveries in #ahga4 ,footnote #aii3 ,see vol4 i41 pp4 #ccf1 #cfd1 #cgj4 ,about #ahbh1 ,mr4 ,rennie1 ,mr4 ,henwood1 and others1 reported on the advantages of high-pressure expansive steam in ,wheal ,towan engine1#bjj on the north cliffs of ,cornwall1 near ,wheal ,seal-hole ,mine on ,st4 ,agnes ,head1 where in #agig ,trevithick had worked his first high-pressure steam-puffer engine in competition with the ,watt low-pressure steam-vacuum engine4 ,captain ,andrew ,vivian was then his companion1 and the ,cow and ,calf1 two rocks of unequal size1 a mile from the land1 were from that time called ,captain ,dick and ,captain ,andrew1 or the ,man and his ,man1 and there they still remain in the ,atlantic waves1 fit emblems of their namesakes and their still living inventions4 ,the stir made by those expansive trials led to the experiment in the ',echo1' of which ,mr4 ,henwood#bja thus speaks3-- ,footnote #bjj3 ,see ,mr4 ,henwood's report1 vol4 ii41 p4 #ahe4 ,footnote #bja3 ,residing at ,penzance1 #ahga4 ,captain ,william ,king1 ,r4,n41 ,superintendent of the ,packet ,station at ,falmouth1 attempted to impress on ,viscount ,melville1 then ,first ,lord of the ,admiralty1 the advantage of using high-pressure steam expansively in the ,royal ,navy1 to whom ,lord ,melville replied that he had been taught by his friend1 the late ,mr4 ,rennie1 that the danger attending such a course was very great1 and that it would be difficult1 if not impossible1 to persuade him to the contrary4 ,illustration3 ,,captain ,,dick ,,and ,,captain ,,andrew1 ,,or ,,the ,,man ,,and ,,his ,,man4 ,w4 ,j4 ,welch4 ,twenty-five years of precept and example caused the ,admiralty to follow suit1 and to request ,mr4 ,ward1 a ,cornish engineer1 to construct boilers and expansive valves for the ,government steamboat ',echo4' ,the writer was entrusted with fixing the machinery in the vessel at the ,plymouth ,dockyard1 and before starting with it from ,harvey and ,co4's foundry1 waited on ,captain ,king1 ,r4,n41 at ,falmouth1 for his instructions1 in happy ignorance of the fear of the ,lords of the ,admiralty to tread on ,cornish high-pressure4 ,after eying the applicant as captains in ,her ,majesty's service are apt to do when dealing with boys in the civil service1 he vouchsafed to say1 ,mind1 young man1 what you are about1 for if there is a blow up1 by ---- you'll swing at the yard-arm4 ,,chapter ,,xxvii4 ,,heating ,,apparatus--,,marine ,,steam-,,engines--,,reform ,,column4 ,,lauderdale ,,house1 ,,highgate1 ,,mr4 ,,gilbert1 ,march #ast1 #ahcj4 ,sir1--,i have to apologize for my neglect in not calling on you1 but ill-health prevented it4 ,i left home on the #aath ,february1 arrived in town on the #adth1 and remained there until the #bdth1 when ,i was compelled to leave for this place1 having a free good air4 ,i am now taking1 twice a day1 the flowers of zinc1 from which ,i hope to be soon right again4 ,i am much better1 but afraid to enter the city4 ,i hope to be able to call on you before the end of this week1 being very anxious to see you1 having a great deal to communicate respecting the experiments ,i have been making1 which will bear out to the full our expectations4 ,your hot-house apparatus has been finished nearly three months1 all but two or three days' work to fit the parts together2 ,i expect that before this they are in ,penzance1 waiting a ship for ,london4 ,while making a sketch of your work for the founder1 a thought struck me that rooms might be better heated by hot water than by either steam or fire1 and ,i send to you my thoughts on it1 with a sketch for your consideration4 ,i find that steam-pipes applied to heat cotton factories1 with #a surface foot of steam-pipe1 heat #bjj cubic feet of space to #fj degrees4 ,i also found in ,germany1 where all the rooms are heated by cast-iron pipes about the heat of steam1 that #a foot of external flue heated #afj cubic feet of space to #gj degrees4 ,i find also that about #bjj surface feet of steam-engine cylinder-case will condense about as much steam as will produce #ae gallons of water per hour1 and will consume about #d bushels in twenty-four hours to keep the temperature of #bab degrees4 ,one bushel of coal will raise the temperature of #cfjj lbs4 of water from #dj to #bab degrees4 ,a boiler1 as the drawing1 will contain #abjj lbs4 of water1 and consume one-third of a bushel of coal to raise the water from #dj to #bab degrees4 ,it has #dj surface feet of hot sides giving out its heat4 ,the #ab-;inch fire-tube in the boiler would raise the temperature to #bab degrees in about forty minutes4 ,by these proofs it appears that #ej feet of surface steam sides will require #a bushel of coal every twenty-four hours to keep up the boiling heat2 therefore this boiler1 having #dj surface feet1 would give out the heat from one-third of a bushel of coal in twelve hours4 ,now suppose this charge of heat required to be thrown off in either more or less than twelve hours1 the circular curtain would adjust the heat and time for extracting it4 ,illustration3 ,,hot-,,water ,,room-,,warmer4 ,by the foregoing this coal and surface sides would heat to #fj degrees for twelve hours a space of #fhjj cubic feet1 equal to a room of #be feet square and #aa feet high4 ,if this boiler was placed in a room with a chimney1 its water could be heated by having a small shifting wrought-iron chimney-tube of #d inches diameter and #b or #c feet long attached to the end of the boiler while it was getting up steam1 after which it might be removed1 and the doors at both ends of the boiler closed2 and as the boiler contains and retains its heat for twelve hours1 more or less1 it might be run on its wheels to any fire-place or chimney to get charged with heat1 and then run into any room1 where there was no chimney1 or into bed-rooms1 offices1 or public buildings2 it would be free from risk1 not having either steam or loose fire4 ,the circular curtain1 being fast to a wood table1 would by being drawn up or down adjust the required heat and hide the boiler1 and would be warm and comfortable to sit at4 ,i think this plan would save three-quarters of the coal at present consumed2 the expense of the boiler will not exceed #el4 ,when you have taken it into consideration1 please to write me your opinion4 ,i remain1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,p4,s4--,boiler1 #c feet diameter1 #c feet long2 fire-tube1 #ab inches diameter1 placed in the boiler1 the same as my old boilers1 made of iron plates #a_/hth of an inch thick1 weighing about #b cwt4 ,i had a summons to attend at ,guildhall last ,saturday on the coal trade1 and was requested to attend a committee at ,westminster for the same purpose1 in consequence of my applying small engines to discharge ships4 ,i attended1 but with difficulty1 from my ill-health4 ,trevithick was not above scheming for his friend's hot-house1 warming it by a boiler on wheels1 in form like his high-pressure steam-boiler4 ,rooms had before been heated by steam or hot air in pipes2 but he thought a more simple and economical plan was to heat a certain quantity of water to boiling heat at any convenient place having a chimney1 or in the open air1 and then wheel the apparatus into the room to be warmed4 ,if the room had a chimney1 the fire could be kept up1 or the temporary iron connecting chimney be removed and the apparatus wheeled into the middle of the room and used as a table4 ,the scheme promised to be successful1 for in a letter nine months after the former he wrote that he had taken a patent for ,france1 where it had made a great bustle among the scientific class1 for coal in ,paris was #cs4 a hundredweight2 some hot-water room-heaters were the following day to be forwarded from ,london to ,paris2 while the numerous orders were more than he could execute4 ,one in use at the ',george and ,vulture' ,tavern1 of a ,gothic shape1 handsomely ornamented with brass1 about two-thirds the size of the one in ,mr4 ,gilbert's hot-house1 burns #g lbs4 of coal a day1 keeping the room at #fe degrees of heat during fifteen hours4 ,the rage amongst the ladies was to have them handsomely ornamented4 ,believing that they would be remunerative1 he applied for the following ,english patent in ,february1 #ahca4 ,illustration3 ,,plate #af4 ,,heating ,,apparatus4 ,london3 ,e ,f4,n4 ,spon1 #dh4 ,charing ,gross4 ,kell ,bros4 ,lith4 ,london4 ,apparatus for ,heating ,apartments4 #bast ,february1 #ahca4 ,,now ,,know ,,ye1 that in compliance with the said proviso1 ,i1 the said ,richard ,trevithick1 do hereby declare that the nature of my said invention of a method or apparatus for heating apartments1 and the manner in which the same is to be carried into effect1 is shown by the following drawings and description1 where ,fig4 #a1 ,plate ,,xvi41 represents a longitudinal vertical section through the middle of a metallic vessel capable of containing a considerable quantity of water1 with a fire-place in the inside1 surrounded with water in all parts except at the doorway and at an opening where the smoke may pass off into a common chimney4 ,fig4 #b1 a vertical section near the fire-door1 at right angles to the section shown at ,fig4 #a2 with the sections are also shown wheels and handles1 which lie out of the planes of the sections4 ,the letters of reference indicate the same parts in both figures1 a1 the vessel2 b1 the space for containing the water2 c1 the fire-place2 d1 the fire-bars1 or grating2 e1 the ash-pit2 f1 an inner door1 to prevent the air from entering over the fire1 yet allow it to pass into the ash-pit1 and thence up to the fire through the grating2 g1 an outer door1 to be shut when the fire is to be extinguished2 h1 a chimney or flue1 to convey the smoke into a common chimney3 this flue may be removed when the water boils1 and then the opening of the flue may be shut1 to keep in the heat1 either by a door or by a plug fitting the opening2 k1 the cover of the vessel1 having a rim all round1 within which iron cement is to be driven to make the vessel steam-tight2 l1 a hole in the middle of the cover1 into which a plug is dropped having a fluted stem and a flat head ground steam-tight upon the cover2 this plug or valve is for the purpose of allowing the escape of steam if it should be raised above boiling point1 and the valve is taken out when it may be necessary to pour water into the vessel2 m1 four wheels1 on which the vessel may be easily removed from one room to another2 n1 two handles1 to facilitate the removal4 ,to use this apparatus for the warming of an apartment1 the vessel is nearly filled with water1 and placed so near to a chimney in another room1 if more convenient1 that the flue-piece h may convey away the smoke2 a fire is then lighted upon the grating d1 and continued till the water boils1 when the flue-piece is taken away1 and the flue opening stopped with the plug or door1 and also the outer fire-door closed4 ,in this state the apparatus is drawn into the apartment to be warmed1 where it will continue for many hours to give off a most agreeable heat without any of that offensive odour usually experienced from stoves heated by an enclosed fire4 ,figs4 #c1 #d1 #e1 and #f represent another form of my apparatus for heating churches or other large buildings4 ,fig4 #c1 a vertical section1 from ,a to ,b1 of ,figs4 #e and #f1 with a representation of the flue and its flanch1 which lie beyond that section and the fire doorway and its flanch1 which lie nearer1 and also the four wheels1 two of which are on each side of the section4 ,fig4 #e1 a horizontal section1 from ,e to ,f1 of ,figs4 #c and #d4 ,fig4 #f1 a horizontal section1 from ,g to ,h1 of ,figs4 #c and #d1 with a view of the four handles situated at a higher level than the section1 and of the fire-bars at a lower level2 the same letters of reference signify the same parts in all the four figures1 a1 the outer case of the water-vessel2 b1 the cover2 c1 the space for water2 d1 the fire-place and flue2 e1 the fire-bars1 made in two pieces1 to be introduced through the fire doorway2 f1 the ash-pit2 g1 the fire-door2 h1 pipes open at top and bottom1 cemented into holes in the bottom1 and in the cover of the water-vessel2 these pipes are to admit a current of air up through them1 in order the more speedily to carry the heat into the building2 k1 the aperture in the cover1 to supply the vessel with water1 and the plug to keep in the steam2 l1 four wheels1 on which the whole is moved1 each wheel revolving in a recess cast in the bottom of the outer case1 as represented by dotted lines in ,figs4 #c and #d2 m1 four handles2 n1 the flanches of the fire doorway and of the flue1 represented in ,fig4 #d by dotted lines4 ,a pipe to communicate with a chimney while the water is being heated must be made to suit locality1 and therefore cannot require any description4 ,this apparatus can be heated in a vestry room1 and the fire-door and flue closed and then wheeled into the church1 where it will soon diffuse a most comfortable warmth2 or the heat may be kept up while standing in its place by having a constant communication with a chimney1 and thus diffuse a much more salubrious heat than can be obtained by metallic or earthen stoves heated immediately by the fire4 ,it is doubtful if the profits he received from the heating apparatus covered the cost of the patent4 ,the first stove was not unlike his first locomotive boiler4 ,the more highly-finished stove resembled the marine tubular boiler1 also of former years1 in the further application of which we now follow him4 ,,mr4 ,,gilbert1 ,,hayle1 ,january #bdth1 #ahbi4 ,sir1--,since ,i have been down ,i have made a small portable engine1 and set it to work on board a coal-ship for discharging the cargo2 it is very manageable1 and discharges #ajj tons with #a bushel of coal1 without any person to attend it1 there being a string that the man in the hold draws when the coal-basket is hooked1 which is again drawn by the man who lands the basket on the deck2 the string turns and re-turns the engine4 ,it is near a ton weight1 but as ,i find it double the power required1 ,i am now making a smaller one1 #c-a_/b feet high and #c-a_/b feet diameter1 about #ab cwt4 ,i intend this engine to warp the ship1 pump it1 cook the victuals1 take in and out the cargo1 and do all the hard work4 ,the captains are very anxious to get them on board every ship4 ,i think that an engine of #ci cwt4 would propel their ships four miles an hour over and above the other work of the ship1 and would neither be so heavy or take so much room as their present cooking house and furnace4 ,i think that two iron paddles1 one on each side of the rudder1 under the stern1 would do this very well2 they would be in dead water1 and out of the swell of the sea1 and by being deep in the water would have a good resistance4 ,two paddles1 each about #d feet deep and #c feet wide1 would do this1 without their rising out of the water2 therefore their stroke would be nearly horizontal4 ,the return stroke would be in the water4 ,thus1 let the paddle stand perpendicular in the water1 two-fifths of its width on one side1 and three-fifths on the other side1 the centre1 which would turn its edge to the water on its back stroke1 and its flat to the water on the forward stroke2 it would be light1 and out of the way of anything4 ,i have a patent now going through the office for all this1 which will also cover the new principle of returning the heat back again1 as already described to you4 ,the engine for drawing in ,holland will be ready about the end of ,february1 and by that time ,i shall have a complete portable engine ready for ,london for discharging1 when ,i shall be in town4 ,illustration3 ,,boat ,,and ,,propeller4 ,i remain1 ,sir1 ,your very humble servant1 ,,rd4 ,,trevithick4 ,p4,s4--,wheal ,towan engine is working with three boilers1 all of the same size1 and the strong steam from the boilers to the cylinder-case2 the boilers are so low as to admit the condensed water to run back from the case again into the boiler4 ,they find that this water is sufficient to feed one of these boilers without any other feed-water2 therefore one-third of the steam generated must be condensed by the cold sides of the cylinder-case1 and this agrees with the experiments ,i sent to you from ,binner ,downs4 ,wheal ,towan engine has an #hj-;inch cylinder1 and requires #gb bushels of coal in twenty-four hours2 therefore the cylinder-case must in condensing high-pressure steam use #bd bushels of coal in twenty-four hours4 ,boulton and ,watt's case for a #fc-;inch cylinder1 working with low-pressure steam1 condensed only #d-a_/b bushels of coal in equal time1 the proportions of surface being as #aij to #bdj in ,wheal ,towan4 ,nearly five times the quantity was condensed of high steam than of low steam1 proving that there is a theory yet unaccounted for4 ,trevithick's portable high-pressure steam-puffer engine1 when it discharged the first cargo of coal from a vessel at ,hayle1 was worked by the writer2 it stood on the wharf near the ship1 and on a signal from the hold1 steam was turned on1 raising rapidly the basket of coal the required height4 ,in trying how quickly the work could be done the hook missed the basket-rope1 and caught the man under the chin1 swinging him high in the air1 much to the engineman's discomfiture4 ,fortunately the suspended man had the good sense to lay hold of the rope above his head1 and so supporting his weight1 no great harm was done4 ,the object and the means were the revival of the nautical labourer of twenty years before4#bjb ,the boiler was a wrought-iron barrel on its end1 on small wheels1 with internal fire-tube1 in shape like the boiler of the recoil engine of #ahae2bjc but less high in proportion to its diameter4 ,the cylinder was let down into the top of the boiler1 and like ,newcomen's atmospheric engine had no cylinder cover4 ,the piston-rod was a rack giving motion to a small pinion fixed on a shaft on the top of the boiler1 and to a large grooved wheel1 around which was wound the whip-rope from the vessel's hold2 a brake-lever enabled the engineman either to stop or to reduce the speed4 ,four months prior to the date of this letter he had sent a written offer to the ,common ,council of the city of ,london1 offering to provide engines to discharge all coal-ships for the saving he would effect in six months1 or he would supply an engine and boxes complete for #ajj guineas4 ,he at the same time suggested that in place of the baskets holding #a bushel1 iron boxes on wheels1 holding #d bushels1 with a spring steelyard attached1 should be used with his steam-engine1 giving the exact weight without delay4 ,he seems to have forgotten his nautical labourer patented twenty years before2#bjd but yet reproduced something very similar4 ,footnote #bjb3 ,see chapters xiv4 and xv4 ,footnote #bjc3 ,see ,trevithick's letter1 #gth ,may1 #ahae1 vol4 i41 p4 #cfd4 ,footnote #bjd3 ,see vol4 i41 p4 #cbe1 and patent1 #ahji1 vol4 i41 p4 #cjb4 ,every trading vessel was recommended to carry at least a #ab-;cwt4 high-pressure steam-puffer engine1 suitable for warping1 pumping1 and discharging cargo2 but a #cj-;cwt4 engine1 not occupying more room than a caboose1 would in addition cook for the crew1 and propel the vessel at three or four miles an hour4 ,two iron paddles1 like the duck's feet described to his ,binner ,downs friends many years before1#bje were to be fixed on an iron shaft across the stern of the vessel1 receiving from the engine a motion like a pendulum4 ,each duck's foot was an iron plate #d feet deep and #c feet wide1 turning partly round on its iron leg1 to which it was attached as a vane1 about #a foot of its width on one side of its leg1 and #b feet on the other side2 when the leg and foot were drawn toward the vessel1 the foot1 turning on its leg as a centre1 exposed its edge only to the water2 on the reverse movement1 the longer side like a vane turned round until its flat was opposed to the water1 in which position it was kept by a catch until the return movement1 so that when it propelled1 its whole surface pressed against the water1 and when moving in a contrary sense1 only its edge offered resistance to the water4 ,footnote #bje3 ,see ,mr4 ,newton's letter1 vol4 i41 p4 #cdb4 ,the writer has no record of the practical application of the duck's foot as a steamboat propeller2 but the portable puffer-engine now pulls on board the fisherman's heavy nets1 and the magnificent steamer ',adriatic' hoists her sails on iron yards and masts by six of those steam helps4#bjf ,footnote #bjf3 ,see ',illustrated ,news1' #bgth ,april1 #ahgb4 ,twenty years before he had solicited the ,navy ,board to try his iron ships propelled by high-pressure steam-engines1 and had shown their applicability as steam-dredgers2 and again1 shortly after his return from ,america1 he pressed on their attention the same subject under new forms1 followed by communications with their engineer1 ,mr4 ,rennie1 and a proposal to place an engine in a boat at his own cost4 ,the writer has attempted in this and the preceding chapter to classify ,trevithick's schemes1 crowded together in those last years of his life1 but the subjects so run into one another that the acts of twenty years before must be borne in mind to enable the more modern plans to be understood4 ,the letter introducing the surface condenser1 in #ahbh1 at the commencement of the former chapter1 was in a month followed by that recommending a particular kind of paddle to be used as auxiliary steam-power1 and after six months of experiments1 by the patent of #ahca1 and the following correspondence3-- ,,mr4 ,,gilbert1 ,,lauderdale ,,house1 ,,highgate1 ,june #ajth1 #ahcj4 ,sir1--,yesterday ,i saw ,mr4 ,george ,rennie1 and he requested me to write to the ,admiralty1 a copy of which ,i send both to you and to him1 for your inspection4 ,mr4 ,rennie said there was a great deal contained in what ,i had stated to him1 and that he would with pleasure forward my views1 as far as he could with consistency4 ,i remain1 ,sir1 ,your very humble servant1 ,,richard ,,trevithick4 ,,to ,,the ,,right ,,honourable ,,the ,,lords ,,commissioners ,,of ,,the ,,admiralty1 c41 c41 c4 ,,my ,,lords1 ,about one year since ,i had the honour of attending your honourable ,board1 with proposed plans for the improvement of steam navigation2 and as you expressed a wish to see it accomplished1 ,i immediately made an engine of considerable power1 for the express purpose of proving by practice what ,i then advanced in theory4 ,the result has fully answered my expectations2 therefore ,i now make the following propositions to your honourable ,board1 that this entirely new principle and new mode may be fully demonstrated1 on a sufficient scale for the use of the public4 ,i humbly request that your ,lordships will grant me the loan of a vessel of about two or three hundred tons burthen1 in which ,i will fix1 at my own expense and risk1 an engine of suitable power to propel the same at the speed required4 ,no alteration in the vessel will be necessary1 and the whole apparatus required to receive its propelling force from the water can be removed and again replaced with the same facility as the sails1 thus leaving the ship without any apparatus beyond its sides when propelled by wind alone1 and when propelled by steam alone the apparatus outside the ship will receive scarcely any shock from the sea4 ,this new invention entirely removes the great objection of feeding the boiler with salt and foul water1 and not one-sixth part of the room for fuel1 or of weight of machinery now used1 will be required2 it is also much more simple and safe1 not only for navigation1 but for all other purposes where locomotive power is required1 and will supersede all animal power1 as the objections of weight1 room1 and difficulty of getting and of carrying water in locomotive engines is entirely removed4 ,it will therefore prove an investigation of greater utility to the public than anything yet introduced4 ,i have to beg the great favour of your ,lordships appointing not only scientific but practical engineers to inspect my plans1 that you may be perfectly satisfied of their utility1 not only in theory1 but also as to the practicability of carrying the same into full effect4 ,the petition in ,june1 #ahcj1 for the loan of a ,government hulk1 hung fire up to ,january #ahcb1 when an attempt was made to move the ,lords ,commissioners of the ,admiralty by the force of numbers4 ,we1 whose names are hereunto subscribed1 have known ,mr4 ,richard ,trevithick1 of ,hale1 in the county of ,cornwall1 for a period of years1 and during which time his conduct has merited our unqualified approbation4 ,as an engineer of experience and eminence few1 if any1 can surpass him1 and his present improvement of the steam-engine seems to outvie all others4 ,we therefore1 in justice to his talent1 strongly recommend to the ,lords ,commissioners of the ,admiralty that he may be permitted1 at his own costs and charges1 to fit and make trial of his engine in one of ,his ,majesty's vessels4 ,dated in ,london this #bgth day of ,january1 #ahcb4 ,this was sent to ,mr4 ,davies ,gilbert1 who on the same date suggested the following3-- ,,recommendation ,,of ,,mr4 ,,rd4 ,,trevithick1 ,january #bg1 #ahcb4 ,we have not any doubt or hesitation in recommending ,mr4 ,richard ,trevithick as a man of extraordinary powers of mind1 and of fertility of invention4 ,cornwall owes to him much of the improvements that have been made on ,mr4 ,watt's engine--improvements that have reduced the consumption of coal to a third2 nor have his exertions been confined to steam-engines alone4 ,he now proposes to make the same water act over and over again by alternate expansion and contraction1 which plan1 if it succeeds1 will be found of immense importance to vessels and locomotive engines4 ,understanding that ,mr4 ,trevithick is desirous of making the experiment at his own expense1 we clearly recommend that facilities may be afforded him4#bjg ,footnote #bjg3 ,in the handwriting of ,mr4 ,davies ,gilbert4 ,this paltry question with the ,admiralty indirectly produced more trustworthy evidence of the great importance of ,trevithick's inventions than all that has been written of him under the professional terms ,engineers1 and ,engineering4 ,the names are not given of those who believed that he had1 as an established fact1 reduced the consumption of coal in the ,watt engine to one-third2 they were not ,cornishmen1 or they would not have misspelt the word ,hayle1 but they understood the great value of using the same fresh water over and over again in marine steam-engines4 ,mr4 ,mills1 who had taken an active part in the screw-propeller experiments in #ahae1 was again interested in the proposed trial in a ,government ship1 and wrote1 ,i have just left ,captain ,johnstone2 he has communicated with ,faucett and ,co41 ,barnes and ,miller1 and with the firm of ,maudslay4 ,he has had his mind disturbed again by ,maudslay about the greater quantity of water required to condense steam at higher temperatures2 ,i repeated the same as yourself1 about the cylinder full of steam1 atmosphere strong2 however1 he appears quite different to what he was on ,friday4 ,such a clique of professional friends would sink a stronger man than ,trevithick4 ,a year or two from that time the writer designed a high-pressure steam-engine suitable for a steamboat1 and on presenting it to the eminent marine-engine builders whom he served1 was told that the lightness of the engine would cause less profit to the makers4 ,their bills were based on the pounds weight delivered1 and new designs necessitated new patterns and new troubles4 ,it was unreasonable to expect those makers of marine steam-engines to report that ,trevithick knew better than they did4 ,they knew of his screw-propeller experiments fifteen years before1 but they in no way benefited him1 and the ,admiralty ,captain was either a tool in their hands1 or powerless without them4 ,the primary object1 when the loan of the ship was asked1 was the using for marine purposes a high-pressure steam tubular boiler1 combined with tubular condenser1 supplying or returning its water as feed1 thereby avoiding the use of salt water in the boiler2 and this steam-engine1 as shown in his patent of #ahca1 was to be applied either to his screw1 or his duck's foot1 or other propeller2 but during the year or two of suspense1 other schemes for propelling ships had occupied his thoughts1 resulting in the patent of #ahcb4 ,steam-,engines1 #ahcb4 ,,now ,,know ,,ye1 that in compliance with the said proviso1 ,i1 the said ,richard ,trevithick1 do hereby declare the nature of my said invention1 as regards the improvement or improvements on the steam-engine1 to consist in interposing between the boiler and the working cylinder1 in a situation to be strongly heated1 a long pipe formed of a compact series of curved or bent pipes1 which ,i denominate the dry pipes1 or steam-expanding apparatus1 through which dry pipes ,i cause the steam1 after it has been generated in the boiler in contact and consequently saturated with water1 to pass with very great velocity1 in order that it may imbibe a copious supply of additional heat without any addition of water1 and by this additional heat to be expanded into a greater bulk of steam1 of about the same expansive force that it had acquired in the boiler1 by which means ,i obtain a greater volume of steam for use in the working cylinder than the boiler alone would supply2 and in order still further to augment this volume of steam1 ,i place the working cylinder within a case constituting a part of the flue or chimney1 that the cylinder may be kept considerably hotter than the steam employed in it by absorbing a great portion of the heat remaining in the flue after having heated the boiler and the dry pipes1 which heat would otherwise pass away out of the top of the chimney and be wasted1 but by this arrangement is converted into a useful power by further expanding the steam in the cylinder4 ,and ,i do further declare1 that in carrying this part of my said improvement into effect1 ,i do not find it necessary to confine myself to any particular form of boiler1 or arrangement of pipes1 in which the steam is to be heated2 but by preference1 as being very compact in form1 and economical of fuel in using1 ,i make my boiler of a number of upright pipes1 standing upon and communicating with a tubular ring placed around and a little below the fire-grate2 these pipes all surround the fire-place1 except two or three1 the lower ends of which are elevated above the fire-door1 but connected at the bottom by a branch pipe united to one of the adjoining upright pipes1 thereby leaving an opening or place of access to the fire4 ,these pipes all extend upwards to the height of several feet1 according to the quantity of steam required to be raised1 combined with local convenience1 for it is obvious that the power of this boiler to raise steam may be increased either by increase of the length of the pipes1 of their diameters1 or of their numbers4 ,and ,i do lay upon the upper ends of the pipes hereinbefore described and connect with them a tubular ring similar to that upon which the pipes stand1 the two rings and the upright pipes forming together a vessel in which water has free communication by means of the bottom ring to stand at the same level in all the pipes1 and the steam has free communication to pass from all the pipes into the upper ring2 and ,i do1 for the sake of obtaining great heat1 place my system of dry pipes over the fire1 and within the circular row of upright pipes of the boiler hereinbefore described2 and ,i form my dry pipes in pairs1 each pair constituting the figure that is well understood by the term inverted syphon2 and ,i unite several of these syphons together by short bent pipes at the top1 so as to constitute one long zigzag pipe1 through which the steam must successively pass down and up the alternate legs of each syphon with great velocity1 necessary for the rapid absorption of heat in its passage from the boiler to the working cylinder of the engine1 the working cock1 valves1 or slide of which being united by a pipe of communication with that leg which is last in the succession of syphons2 and ,i unite the first in succession of these inverted syphons with the upper tubular ring of the boiler by means of a bent pipe1 in which a throttle-valve or cock is placed in order to limit the supply of steam1 that it may have space in the dry pipes and working cylinder to expand in proportion as it receives additional heat2 and ,i fix a safety-valve in communication with the boiler1 and another in communication with the dry pipes2 and ,i place around outside the boiler1 at a small distance from the upright pipes1 two cylindrical casings1 one within the other1 and fill up the space between the two casings with sand1 ashes1 or other material which conducts heat but slowly2 and ,i close up the upper end of the casings over the boiler and the dry pipes with a covering in the form of a dome1 and out of this enclosure ,i make the flue to pass to and around the working cylinder of the engine1 whence the flue carries the smoke and little remaining heat away in any convenient manner2 and ,i make my boiler-pipes1 rings1 and casings by preference of iron or copper1 and my dry pipes of copper or other strong metal not liable to rapid oxidation by heat when in contact with steam2 and ,i supply my boiler with water by means of a forcing pump1 so adjusted as to keep the water of the proper height4 ,and ,i do hereby further declare1 that the nature of my said invention1 as regards the improvements in the application of steam-power to navigation1 consists in the drawing of water into a receptacle placed near within the stern of the navigable vessel1 which water is drawn in through an orifice in the stern with a moderate degree of velocity in the direction of the course of the vessel1 and ejected with great force and speed in a direction opposite to the course of the vessel through the same orifice1 reduced to about a quarter of the area by means of a valve opening as the water enters1 and partially shutting as the water is ejected2 and thus ,i propel the vessel with great force1 derived from the recoil of the water set into rapid motion in a direction opposite to the course of the vessel1 the rapidity of the jet of water to be at least equal to double the required speed of the vessel to be navigated4 ,and ,i further declare1 that by preference ,i effect the purpose of receiving and of ejecting the water1 and of deriving a motive force from its recoil1 by means of a large vertical cylinder of cast iron or other metal1 closed at both ends1 in which a piston is forced up and down by a piston-rod sliding through a stuffing box in the lid1 which piston-rod receives its motive force from a steam-engine2 and ,i fix a tube into the after side of this cylinder1 near the bottom1 in communication with the space below the piston1 which tube leads through the stern of the vessel1 as low down as practicable1 and opens on one side of the rudder2 and ,i fix another tube into the after side of this cylinder1 near the top1 in communication with the space above the piston1 which tube also leads through the stern of the vessel1 as low down as practicable1 but opens out on the other side of the rudder2 and ,i place in the mouth of each of these tubes a valve opening inwards1 to allow the water free entrance1 equal to the bore of the tube1 and partially shutting when the water is ejected1 so as to reduce the opening through the stern to about one-fourth of the area of the tube4 ,and ,i do hereby further declare1 that the nature of my said invention1 as regards the improvement in the application of steam-power to locomotion1 consists in the application of such a boiler1 together with the expanding apparatus as aforesaid1 to locomotive engines1 whereby a diminished weight of boiler and quantity of water and fuel is obtained2 and in farther compliance with the said proviso1 ,i1 the said ,richard ,trevithick1 do hereby describe the manner in which my said invention is to be performed1 by the following description of its various parts in detail1 reference being had to the drawing annexed1 and to the figures and letters marked thereon1 that is to say3-- ,description of the ,drawing4 ,plate ,,xvii4 ,illustration3 ,,plate #ag4 ,,trevithick',s ,,patent ,,boiler ,,and ,,engine1 #ahcb4 ,london3 ,e4 ,f4,n4 ,spon4 #dh1 ,charing ,cross4 ,kell ,lith4 ,london4 ,figure #a represents a series of vertical sections through the various essential parts of the boiler1 the dry pipes1 the steam-pipe1 the working cylinder1 the propelling cylinder1 and the flue1 together with sections and views of other minor parts1 serving to show the connections of the essential ones4 ,the places at which these sections are taken are shown in ,figure #b by the dotted line from ,a to ,b1 from ,b to ,c1 from ,c to ,d1 and from ,e to ,f4 ,figure #b represents a plan of ,figure #a1 with the top coverings of the boiler and working cylinder removed4 ,figure #c shows the manner of uniting the shorter upright pipes over the fire doorway with one of the adjoining ones1 so as to give free circulation of the water in all the pipes4 ,figure #d represents three pairs of syphons1 which in their places stand in a circular form1 but in this ,figure are shown as spread out into a plane1 in order the better to explain their structure and joinings4 ,similar small letters and numbers of reference are used to denote similar parts in all the ,figures2 a1 the upright boiler-pipes1 the upright and lower ends of which are contracted to leave room for bolt-heads and nuts1 without throwing the pipes too far asunder2 b1 the tubular ring having a flanch projecting inwards and outwards at the upper side1 perforated with apertures upon which the upright pipes are bolted1 and another flanch at the bottom1 projecting inwards1 to bolt the ring down to the foundation plate2 c1 the foundation plate2 d1 the fire-grate2 e1 the fire doorway2 f1 the upper tubular ring1 having a flanch at the bottom projecting inwards and outwards1 and perforated with apertures corresponding with the tops of the upright pipes upon which the tubular ring lies1 and to all which it is bolted2 g1 the level of the water in the boiler-pipes2 h1 the dry pipes formed like inverted syphons1 so as to require no joining at the lower part near the fire2 one leg of each of the two syphons shown in ,figure #a is in section1 and broken near the bottom2 an outside view of the other leg appears partly behind the section2 k1 the short bent pipes1 each bolted to two syphons1 to unite them into one continuous pipe2 l1 the bent pipe uniting the upper tubular ring with the first in succession of the syphons2 the proper situation for this pipe is that shown in ,figure #b1 but for the sake of clearness and simplicity in the drawing1 it is shown in ,figure #a as if on the left-hand pipe and syphon2 m1 the throttle-cock on the bent pipe l2 n1 the safety-valve lever1 and weight on the same2 p1 the pipe of communication from the last in the succession of syphons to the working cylinder of the engine2 r1 the throttle-cock in the pipe p2 s1 a four-way cock1 worked by the hand-gear1 to direct the steam alternately under and over the piston2 t1 the safety-valve in communication with the dry pipes2 u1 the two cylindrical casings surrounding the boiler-pipes1 the space between the two being filled up with a slow conducting medium2 v1 the domical covering over the cylindrical enclosure2 w1 the flue leading out of the enclosure into the casing of the working cylinder2 x1 the casing of the working cylinder forming a continuation of the flue2 y1 the further continuation of the flue to the chimney2 z1 the waste-steam pipe leading into the chimney2 #a1 the steam-pipes leading from the working cock into the top and bottom of the working cylinder2 #b1 the working cylinder2 #c1 the piston with metallic packing2 #d1 the piston-rod passing down through a stuffing box at the bottom of the working cylinder1 and also continuing downwards1 to form the rod of the propelling piston2 #e1 the propelling cylinder2 #f1 the water or propelling piston2 #g1 the upper aperture leading to one of the tubes opening through the stern of the navigable vessel2 #h1 the lower aperture leading to the other tube1 opening also through the stern of the navigable vessel2 these apertures are made as wide as the cylinder will allow1 in order that they may have but little depth1 and not occasion an inconvenient length of the propelling cylinder2 #i1 a frame supporting the steam-cylinder upon the propelling cylinder2 #aj1 the feed-pump for supplying the boiler with water2 #aa1 an arm fastened on the piston-rod to work the feed-pump and hand-gear2 #ab1 the hand-gear4 ,now1 whereas ,i claim as my invention1 firstly1 the interposing between the boiler and the working cylinder of the steam-engine a long many-curved heated pipe1 through which the steam is forced to pass with great rapidity without being permitted to come in direct contact with water1 by which arrangement the steam is made to absorb additional heat1 and at the same time allowed to expand itself into a greater volume4 ,secondly1 placing the working cylinder of the engine within such part of the flue or chimney as shall ensure the cylinder to be kept hotter than the steam used in it1 by which means the expanding of the steam is still further promoted4 ,thirdly1 propelling a navigable vessel by the force of the recoil produced from water received with a moderate degree of velocity1 into a receptacle near within the stern1 in the direction of the course of the vessel1 and ejected with great velocity in a direction opposite to that course1 the velocity of the jet being at least double the required speed of the vessel to be propelled1 provided always that the same be effected in manner hereinbefore described4 ,fourthly1 applying a boiler combined with a steam expanding apparatus1 as before described1 instead of a boiler alone1 to a locomotive engine1 whereby the power of the steam is applied after the steam has undergone the expanding process1 and whereby a diminution is effected in the weight of the boiler1 and in the weight and consumption of water and of fuel4 ,the two great objects in this #ahcb patent were superheating steam in tubular boilers1 and propelling ships by forcing a stream of water from the stern at a speed of at least double that of the vessel4 ,similar ideas may be traced in his patent of #ahae1 where a tubular boiler gave superheated steam1 and in #ahji his patent for propelling steamboats consists of a tube of considerable length disposed horizontally in the water1 and the stroke of rowing is made by means of a piston with valves4 ,an engine of #ajj-;horse power was ordered in ,shropshire to be placed on board the ,government ship to test the value of those patents of #ahca and #ahcb4 ,one consequence was that a gentleman who had helped this scheme with his money wrote3-- ,my case with ,trevithick is strictly this2 he was represented to me as a man of property2 and as to his talents for mechanics1 no man could be in his company long without being struck with them4 ,i was induced to trust him to the amount of nearly #ejjl41 and ,i then learned for the first time that it was only on the possible contingency of a grant from ,government that he relied for the payment of my claim4 ,a company called the ,new ,improved ,patent ,steam-,navigation ,company was formed1 of which ,trevithick was a member1 though apparently not a subscriber1 for a note in ,november1 #ahca1 informed him that if in seven days he did not pay up his calls1 his shares would be entirely forfeited4 ,this company1 among other proposals1 opened negotiations for sending steamboats to ,buenos ,ayres to help in the commerce of the port and inland river4 ,in #ahcb the ,waterwitch ,company made experiments with those plans1 propelling by forcing water through pipes1 since which a ,government ship of war called the ',waterwitch' has been so propelled4 ,twenty years ago the writer saw steamboats so propelled in daily use on the ,meuse2 they needed no rudder1 for by turning the mouth of the exit-water pipes on either side of the ship it was made to turn in its length1 or even to move sideways4 ,messrs4 ,john ,hall and ,sons1 of ,dartford1 also experimented on these two patents1 and from this the tubular condenser was called ,hall's ,condenser4 ,i think the boat it was first tried in was called the ',dartford4' ,trevithick's difficulties in urging so many and great changes in marine propulsion may be estimated by the acts of other engineers4 ,mr4 ,rennie was engaged for many years in urging the introduction of steam-power in the ,royal ,navy4 ,in #ahag1 we find him writing to ,lord ,melville1 ,sir ,j4 ,yorke1 ,sir ,d4 ,milne1 and others on the subject4 ,in ,july1 #ahah1 he laments that he cannot convince ,sir ,g4 ,hope or ,mr4 ,secretary ,yorke of their utility1 but that he is persuaded their adoption must come at last4 ,on the #cjth ,may1 #ahbj1 he writes ,james ,watt1 of ,birmingham1 informing him that the ,admiralty had at last decided upon having a steamboat1 notwithstanding the strong resistance of the ,navy ,board4#bjh ,footnote #bjh3 ',lives of the ,engineers1' by ,smiles1 vol4 ii41 p4 #bfg4 ,so that ,mr4 ,bennie1 as professional adviser of the ,navy ,board1 had to persuade for three years1 with a knowledge of ,trevithick's prior experiments1 before active steps were agreed to2 for twelve years had then passed since ,trevithick's nautical labourer and iron steamboat had been tried on the ,thames1 and five since his experiments with the screw-propeller4 ,an article in ',the ,times' gives in strong contrast the relative value of screw and paddle-wheels as propellers4 ,the ',syria' was originally a paddle-wheel steamer1 having oscillating cylinders worked with steam of #be lbs4 on the inch1 and ,hall's tubular condenser2 after a time the paddle-wheels were removed for a screw-propeller1 driven by two steam-cylinders side by side1 of different diameters1 the high-pressure steam exerting its full force in the small cylinder1 and then expanding in the larger cylinder4 ,all the leading features in this improved steamboat of the present day1 such as high-pressure expansive steam in one or two cylinders1 with tubular condenser and screw-propeller1 had been publicly proved by ,trevithick fifty years before4 ,illustration3 ,,plate #ah4 ,,compound ,,marine ,,engine1 #ahga4 ,london3 ,e4 ,f4 ,n4 ,spon1 #dh1 ,charing ,cross4 ,kell ,bros4 ,lith4 ,london4 ,screw against ,paddle4--,an interesting and important trial trip has recently been made1 which serves to exhibit the advantages of the screw over the paddle as a means of propulsion for ocean-going steamships4 ,in #ahfc1 the steamship ',syria1' of #aiih tons1 was built for the ,peninsular and ,oriental ,company by ,messrs4 ,day1 ,summers1 and ,co41 and fitted with paddle-wheel engines of #dej-;horse power4 ,the ',syria' then attained a speed of #acjch knots per hour1 and the consumption of coal was at the rate of #de tons per diem4 ,the builders have lately converted her into a screw-steamer 7for carrying the mails between ,southampton and the ,cape of ,good ,hope71 who1 without in any way disturbing the configuration of the hull1 have fitted the ',syria' with compound inverted engines of #cjj nominal horse-99power4 ,these engines have two cylinders1 respectively of #cf in4 and #gb in4 diameter1 with a stroke of #d ft4 #b in4 ,on ,monday last the ',syria' attained an average speed of #abfcg knots1 with a consumption of coal equivalent to #ah tons per diem2 thus showing a difference of only #jdja knot per hour1 with a lessened power of #aej horses1 and a saving in consumption of coal of #bg tons per diem2 while the carrying capacity of the ship1 arising from the economy of space in the engine-room1 has been enormously increased1 as she can now stow #abjj tons of cargo against #ejj tons previously4#bji ,footnote #bji3 ,see ',the ,times1' ,may #bjth1 #ahga4 ,mr4 ,husband1 of the firm of ,harvey and ,co41 of ,hayle1 has obliged me with the annexed sketch 7,plate ,,xviii47 of a modern high-pressure steam expansive compound marine engine1 with surface condensers1 on which the grandsons of ,trevithick are now working1 to be placed in the ',batara ,bayon ,syree1' an iron yacht for an ,indian ,rajah1 embracing the modern improvements of direct-action compound engines1 and illustrating the principles which governed the constructors of the ',syria4' ,the first glance shows a seeming resemblance in outline to ,trevithick's patent drawing of #ahcb1 having one cylinder above the other2 but a closer examination proves the application of the principles of his patents of #ahae and #ahca1 embracing screw-propeller1 direct-acting engines1 tubular boilers1 high-pressure steam used expansively1 and condensation by cold surface preventing the necessity of using salt water in the boilers4 ,this engine1 in outline1 has a strong likeness to ,trevithick's engines1 going back even to his first patent of #ahjb1baj followed by the direct-action high-pressure steam yacht of #ahjf1baa and again in #ahjhbab by the iron steamer with direct-action long-stroke cylinders1 with highly expansive steam and surface condensers1 to which1 in #ahae1bac was added the patent compound expansive steam pole and piston engine and screw-propeller1 embodying during the first fifteen years of the present century1 both in principle and in detail1 the most approved form of marine steam-engine with fewness and simplicity of form of moving parts2 but compare it with the ,watt patent engine1 and its difference is obvious2 no beam or parallel motion1 no injection-water necessitating the air-pump1 no low-pressure steam4 ,the late ,mr4 ,william ,wilson1 of ,perran ,foundry1 son of ,boulton and ,watt's financial agent in ,cornwall1 informed ,mr4 ,henwood that he was with ,mr4 ,watt when some one stated that ,mr4 ,trevithick was working his engine with steam of #dj lbs4 on the inch2 when ,mr4 ,watt replied1 ,i could work my engine with steam of #ajj lbs4 to the inch1 but ,i would not be the engineman4#bad ,footnote #baj3 ,see vol4 i41 p4 #ei4 ,footnote #baa3 ,see vol4 i41 p4 #cbg4 ,footnote #bab3 ,see vol4 i41 p4 #chf4 ,footnote #bac3 ,see vol4 ii41 p4 #ajc4 ,footnote #bad3 ,henwood1 ,address to the ,royal ,institution of ,cornwall1 #ahga4 ,progressive experience1 with increasing demand for economy and speed1 have caused the principles and the details of ,trevithick's steam-engines to be matters of national importance seventy years after their discovery1 for as far back as that he used highly-expansive steam1#bae and on the question of a separate cylinder for expansion as used in the modern steamboat combined engines1 he wrote1 ,i think one cylinder partly filled with steam would do equally as well as two cylinders2 that one at ,worcester shuts off the steam at the first third of the stroke1 and works very uniformly with a considerable saving of coal4#baf ,those modern marine engines use about the same steam pressure and expand about in the same proportion4 ,with the direct action from the piston-rod to the crank-shaft1 the multitubular boiler and screw-propeller1 and the surface condenser perfected in #ahca and #ahcb1 at which time his construction of a marine steam-engine would have been just what it now is forty years later4 ,those latter patents also embrace the principle of superheating steam1 practically shown many years before1#bag and still used by marine engineers of modern times4 ,footnote #bae3 ,see ,trevithick's letter1 #bbnd ,august1 #ahjb1 vol4 i41 p4 #aec4 ,footnote #baf3 ,see ,trevithick's letter1 #eth ,july1 #ahjd1 vol4 ii41 p4 #acb4 ,footnote #bag3 ,see ,trevithick's letter1 #afth ,may1 #ahae1 vol4 i41 p4 #cgj4 ,in tracing the wisdom of his designs just before the close of an eventful life1 reference may be made to the trial of a common road locomotive in #ahga3--;,experimental trip of the ,indian ,government steam train engine1 ',ranee1' from ,ipswich to ,edinburgh4--,the results of the trial with the ',chenah1' though satisfactory so far as the engines proper were concerned1 were vitiated by the failure of the boiler2 on the completion of the second engine1 the ',ranee1' the field boiler and variable blast-pipe were used2 the boiler is about #d feet diameter at the bottom and #h feet high4#bah ,footnote #bah3 ',the ,engineer1' #bgth ,october1 #ahga4 ,the form and dimensions of the exterior of the ,ranee tubular boiler are very similar to ,trevithick's patent drawing and specification of #ahcb2 even the variable blast-pipe was used by him in #ahjb4bai ,footnote #bai3 ,trevithick's letter1 #bbnd ,august1 #ahjb1 vol4 i41 p4 #aec4 ,the last years of ,trevithick's eventful life were chequered with hopes and disappointments when1 in the early part of #ahcj1 he wrote to his friend ,gerard3-- ,this morning ,i called here for the purpose of forwarding my information to the committee of the ,house4 ,i called on ,mr4 ,thompson to inform him what ,mr4 ,gilbert said respecting it4 ,his answer was1 that the direct method would be by forwarding a petition in the way proposed when at the lobby4 ,in consequence1 ,i have forwarded the petition to ,sir ,matthew ,ridley4 ,yesterday ,i took the coach to ,highgate1 by way of ,camden ,town1 and of course had to walk up ,highgate ,hill4 ,i found ,i was able to walk up that hill with as much ease and speed as any of my coach companions4 ,however strange this maggot may appear in my chest and brain1 it is no more than true4 ,i wish among all you long-life-preserving doctors you could find out the cause of this defect1 so as to remedy this troublesome companion of mine4 ,his health was breaking down1 and his petition for a gift from the public purse1 so hopefully commenced two years before1 was doomed1 after another year's bandying from pillar to post1 to be forgotten and unanswered4 ,,dear ,,trevithick1 ,,eastbourne1 ,december #bfth1 #ahca4 ,i am sorry to find that you have not any prospect of assistance from ,government4 ,i have not any copy or memorandum of my letter to ,mr4 ,spring ,rice1 but it was to the effect of first bearing testimony to the large share that you have had in almost all the improvements on ,mr4 ,watt's engine1 which have altogether about trebled its power2 your having made a travelling engine twenty-eight years ago2 of your having invented the iron tanks for carrying water on board ship4 ,i then went on to state that the great defect in all steam-engines seemed to be the loss by condensation of all the heat rendered latent in the conversion of water into steam4 ,that high-pressure engines owed their advantages mainly to a reduction of the relative importance of this latent heat4 ,that ,i had long wished to see the plan of a differential engine tried1 in which the temperatures1 and consequently elasticities1 of the fluid might be varied on the opposite sides of the piston without condensation2 that the engine you had now constructed promised to effect that object1 and that in the event of its succeeding at all1 although it might not be applicable to the driving water out of mines1 yet that for steam-vessels and for steam-carriages its obvious advantages would be of the greatest importance2 and ,i ended by saying that although it was clearly impossible for me to ensure the success of any plan till it had been actually proved by experiment1 yet judging theoretically1 and also from the imperfect trial exhibited on the ,thames1 ,i thought it well worthy of being favoured4 ,your plan unquestionably must be to appoint some one with you1 as ,mr4 ,watt did ,mr4 ,boulton1 and ,i certainly think it a very fair speculation for any such person as ,mr4 ,boulton to undertake4 ,it is impossible for me to point out any individual1 as never having had the slightest motive with such or with manufacturers in any part of my life1 ,i am entirely unacquainted with mercantile concerns4 ,i cannot1 however1 but conjecture that you should make a fair and full estimate of what would be the expense of making a decisive experiment on a scale sufficiently large to remove all doubt2 and that your proposal should be1 that anyone wishing to incur that expense should1 in the event of success1 be entitled to a certain share of your patent2 on such conditions some one of property may perhaps be found who would undertake the risk1 and if the experiment proved successful1 he would be sure to use every exertion afterwards for his own sake4 ,with every wish for your success1 ,believe me1 yours very faithfully1 ,,davies ,,gilbert4 ,the statement of the ,president of the ,royal ,society1 that the power of the ,watt engine had been trebled by ,trevithick1 brought him no gain4 ,he never troubled himself with politics1 but the passing of the ,reform ,bill caused him to suggest that it should be commemorated by a pillar higher than had ever before been erected4 ,the following memorandum is in his own writing3-- ',morning ,herald1' ,july #aath1 #ahcb4 ,national ,monument in honour of ,reform4--,the great measure of ,reform having become the law of the land1 it is proposed to commemorate the event by the erection of a stupendous column1 exceeding in dimensions ,cleopatra's ,needle1 or ,pompey's ,pillar1 and symbolical of the beauty1 strength1 and unaffected grandeur of the ,british ,constitution4 ,in furtherance of this great object1 a public meeting is proposed to be held1 of which due notice will be given1 to set on foot a subscription throughout the ,united ,kingdoms1 limiting individual contributions to two guineas1 but receiving the smallest sums in aid of the design4 ,the following noblemen and gentlemen have signified their approbation of the measure3--,his ,grace the ,duke of ,norfolk1 of ,somerset1 of ,bedford2 the ,right ,honourable ,earl of ,morley1 of ,shrewsbury1 of ,darlington2 ,lord ,stafford2 ,sir ,francis ,burdett1 ,m4,p42 ,joseph ,hume1 ,m4,p42 ,r4 ,h4 ,howard1 ,m4,p42 ,win4 ,brougham1 ,m4,p42 ,j4 ,e4 ,denison1 ,m4,p42 ,a4 ,w4 ,robarts1 ,m4,p42 ,j4 ,easthope1 ,m4,p42 ,general ,palmer1 ,m4,p4 ,design and specification for erecting a gilded conical cast-99iron monument4 ,scale1 #dj feet to the inch of #ajjj feet in height1 #ajj feet diameter at the base1 and #ab feet diameter at the top2 #b inches thick1 in #aejj pieces of #aj feet square1 with an opening in the centre of each piece #f feet diameter1 also in each corner of #ah inches diameter1 for the purpose of lessening the resistance of the wind1 and lightening the structure2 with flanges on every edge on their inside to screw them together2 seated on a circular stone foundation of #f feet wide1 with an ornamental base column of #fj feet high2 and a capital with #ej feet diameter platform1 and figure on the top of #dj feet high2 with a cylinder of #aj feet diameter in the centre of the cone1 the whole height1 for the accommodation of persons ascending to the top4 ,each cast-iron square would weigh about #c tons1 to be all screwed together1 with sheet lead between every joint4 ,the whole weight would be about #fjjj tons4 ,the proportions of this cone to its height would be about the same as the general shape of spires in ,england4 ,illustration3 ,,plan ,,and ,,sectional ,,elevation ,,of ,,proposed ,,reform ,,column4 ,a steam-engine of #bj-;horse power is sufficient for lifting one square of iron to the top in ten minutes1 and as any number of men might work at the same time1 screwing them together1 one square could easily be fixed every hour2 #aejj squares requiring less than six months for the completion of the cone4 ,a proposal has been made by iron founders to deliver these castings on the spot at #gl4 a ton2 at this rate the whole expense of completing this national monument would not exceed #hj1jjjl4 ,by a cylinder of #aj feet diameter1 through which the public would ascend to the top1 bored and screwed together1 in which a hollow floating sheet-iron piston1 with a seat round it1 accommodating #be persons2 a steam-engine forces air into the cylinder-column from a blast-cylinder of the same diameter and working #c feet a second1 would raise the floating piston to the top at the same speed1 or five or six minutes ascending the whole height2 the descent would require the same time4 ,a door at the bottom of the ascending cylinder opens inwards1 which1 when shut1 could not be opened again1 having a pressure of #aejj lbs4 of air tending to keep it shut until the piston descends to the bottom4 ,by closing the valve in the piston it would ascend to the top with the passengers floating on air1 the same as a regulating blast-piston1 or the upper plank of a smith's bellows4 ,the air apparatus from the engine should be of a proper size to admit the floating piston with the passengers to rise and fall gradually1 by the partially opening or shutting of the valves in the top of the piston4 ,supposing no springs or soft substance for the piston to strike on at the bottom of the column-cylinder1 descending #c feet a second would give no greater shock than falling from #i inches high1 that being the rate of falling bodies1 or the same as a person being suddenly stopped when walking at the rate of two miles an hour4 ,the pressure of the air under the piston would be about #a_/b lb4 on the square inch2 the aperture cannot let the piston move above #c feet a second1 but this speed may be reduced to any rate required by opening or shutting the valves on the floating piston4 ,illustration3 ,,general ,,view ,,of ,,reform ,,column4 ,to ,trevithick's soaring genius nothing appeared very small1 or very large1 or very costly2 not even the cast-iron column #ajjj feet high covered with gold4 ,the stone monument of ,london1 #baj feet high1 is admired by many2 others climb into the cross on ,st4 ,paul's ,cathedral1 #dbj feet high2 some make a long journey to the great ,pyramids1 #ejj feet high4 ,how much more pleasant would be ,trevithick's proposed floating #ajjj feet upward on an air-cushion1 controlled by his high-pressure steam-engine1 and having1 from the loftiest pedestal of human art1 surveyed imperial ,london1 to be again lowered to the every-day level at a safe speed1 regulated by valves closed by such simple acts as rising from the seat2 but should this be neglected1 the passage of compressed air escaping from under the piston-carriage would only allow of its descent at a speed of #c feet in a second1 giving but the same shock on bumping the bottom as jumping off a #i-;inch door-step4 ,perhaps the ,king in #ahcc could not take an active part in advocating a memento of the golden days of reform2 but this is no reason why the suggestion should have been so slightly noticed in #ahfb1 to erect it in memory of the good and wise ,prince ,albert4 ,various meetings were held1 and after nine months the plan had so far advanced as to be placed before the ,king4 ,sir ,herbert ,taylor begs to acknowledge the receipt of ,mr4 ,r4 ,trevithick's letter1 with the accompanying design for a national monument1 which he has had the honour of submitting to the ,king4 ,,st4 ,,james',s ,,palace1 #ast ,march1 #ahcc4bbj ,footnote #bbj3 ,the column was suggested in #ahfb as a suitable monument to the memory of the late ,prince ,albert4 ,within two months from the date of the design for a gilded column ,trevithick had passed away4 ,his family in ,cornwall received a note1 dated #bbnd ,april1 #ahcc1 from ,mr4 ,rowley ,potter1 of ,dartford1 stating that ,trevithick had died on the morning of that day1 after a week's confinement to his bed4 ,he was penniless1 and without a relative by him in his last illness1 and for the last offices of kindness was indebted to some who were losers by his schemes4 ,the mechanics from the works of ,messrs4 ,hall were the bearers1 and mourners at the funeral1 and at their expense night watchers remained by the grave to prevent body-snatching1 then frequent in that neighbourhood4 ,a few years after the funeral1 the writer was refused permission to go through the works to inquire into the character of the experiments that had been tried1 but the working mechanics were glad to see the son of ,trevithick1 and their wives and children joined in the welcome as he passed through the small town4 ,trevithick's grave was among those of the poor buried by the charitable2 no stone or mark distinguished it from its neighbours4 ,he is known by his works4 ,his high-pressure steam-engine was the pioneer of locomotion and its wide-spreading civilization4 ,england's mineral and mechanical wealth on land or sea are indebted to its expansive power1 its applicability1 and durable economy4 ,his comprehensive and ingenious designs1 given to the world seventy years ago1#bba are still instructive guides2 and many of his works1 dating from the dawn of the present century1 remained as active evidences of his skill almost to the present day1 with their three-score years1#bbb while some few reaching three-score years and ten still remain good servants#bbc in the solitude of the ,peruvian mountains1 where no mechanical hand repairs the errors of human skill or the wear and tear of time4#bbd ,footnote #bba3 ,see #ahjb patent1 vol4 i41 p4 #abh4 ,footnote #bbb3 ,see vol4 i41 pp4 #bbb1 #ajj1 #hb1 #ahd4 ,footnote #bbc3 ,agricultural engine1 vol4 ii41 p4 #fh4 ,footnote #bbd3 ,see vol4 ii41 p4 #bbj4 ,if these material proofs fail to convince1 the reader has but to ponder on the bitterly natural reflections written by himself a few months before his last illness to his friend ,davies ,gilbert3-- ,i have been branded with folly and madness for attempting what the world calls impossibilities1 and even from the great engineer1 the late ,mr4 ,james ,watt1 who said to an eminent scientific character still living1#bbe that ,i deserved hanging for bringing into use the high-pressure engine4 ,this so far has been my reward from the public2 but should this be all1 ,i shall be satisfied by the great secret pleasure and laudable pride that ,i feel in my own breast from having been the instrument of bringing forward and maturing new principles and new arrangements of boundless value to my country4 ,however much ,i may be straitened in pecuniary circumstances1 the great honour of being a useful subject can never be taken from me1 which to me far exceeds riches4 ,footnote #bbe3 ,mr4 ,john ,isaac ,hawkins4 ,,index ,,to ,,volume ,,ii4 ,a4 ,,abadia1 ,don ,,pedro1 #bag1 #bai1 #bba1 #bbi1 #bca1 #bcf1 #bdc1 #bde1 #bdg4 ,,abinger1 ,lord1 #cjc4 ,,adams1 ,mr41 #id4 ,,admiralty1 #caa1 #cch1 #cef1 #ceh1 #cfa1 #cgb1 #chd4 ,,adriatic ,,steamer1 #cgb4 ,a,,rated ,,steam1 #g1 #aa4 ,,agricultural ,,engine1 #ag1 #ah1 #ai1 #cf1 #dj1 #da1 #db1 #dg1 #ej1 #ec1 #eh4 ,,agricultural ,,machine1 #eh4 ,,air-,,engine1 #bib4 ,,air-,,pump1 #ai1 #ajc1 #abb4 ,,ajerbi ,,river1 #bff4 ,,alverado1 #bfj1 #bfa4 ,,amalgamation1 #bfa4 ,,amputation1 #bga4 ,,application ,,to ,,parliament1 #ahc1 #cag4 ,,aquacate1 #bfg4 ,,arismendi1 ,don ,,jos1 #bag1 #bai1 #bba1 #bbi4 ,,armstrong1 ,sir ,,william1 #bid4 ,,artha1 ,captain1 #fj1 #fd1 #fi1 #ajb4 ',,asp1' ,,ship1 #bbh1 #bci4 ,b4 ,,bailiffs1 #cf4 ,,banfield1 ,mr41 #ej4 ,,banfield1 ,mr4 ,j41 #fe1 #gd1 #aec4 ,,barnes and ,,miller1 #cge4 ,,bedford1 ,duke of1 #cij4 ,,beeralstone1 #hg1 #ajb4 ,,bennetts1 ,,frank1 #abi4 ,,bickle1 ,mr41 #fe4 ,,binner ,,downs1 #cae1 #cbc1 #cbg1 #cfi4 ,,blacklead1 #d1 #ach4 ,,blast ,,by ,,cylinder1 #cdc1 #ceb4 ,,blast ,,by ,,screw1 #cda4 ,,blast-,,furnace1 #f4 ,,blast-,,pipe1 #id1 #ada1 #add1 #baj4 ,,blewett1 ,captain1 #agd4 ,,blewett1 ,mr41 #ea4 ,,boiler1 #g1 #ad1 #ai1 #cb1 #da1 #fj1 #ff1 #fi1 #gd1 #ha1 #hd1 #ib1 #ajb1 #aae1 #aai1 #abd1 #abf1 #ach1 #adb1 #ade1 #aec1 #aef1 #aei1 #afi1 #ahj1 #ahc1 #bac1 #bbg1 #bij1 #cjj1 #cjh1 #cba1 #cbg1 #cci1 #cdc1 #cef1 #ceg1 #cei1 #cfi1 #cgg4 ,,bolivar1 ,president1 #beb1 #bed4 ,,booth1 ,mr41 #ced4 ,,borer ,,of ,,rock1 #bd1 #bg4 ,,bottle-,,neck ,,boiler1 #ceg4 ,,breakwater1 #bb4 ,,bridgenorth1 #c1 #hg4 ,,brougham1 ,mr41 #cij4 ,,bryant1 ,,john1 #aee1 #afc1 #afd4 ,,budge1 ,mr41 #abf4 ,,buenos ,,ayres1 #ca1 #bbg1 #chc4 ,,bull1 ,mr41 #hd1 #aah1 #bac1 #bcj1 #bcg1 #bdd1 #bdf4 ,,bullan ,,garden1 #aaf1 #aba1 #aee1 #agg4 ,,burdett1 ,sir ,,francis1 #cij4 ,,burral1 ,jun41 ,mr41 #ff4 ,,burral1 ,sen41 ,mr41 #ajb4 ,,bushel1 #df1 #hc1 #if1 #ahb4 ,,bust1 #bde4 ,c4 ,,camborne1 #aaj4 ,,campbell and ,co41 #bja1 #bcj4 ,,canal ,,boat1 #ag4 ,,carloose ,,engine1 #aaf1 #abj1 #aee1 #agg4 ,,carriage-,,wheels1 #bjg4 ,,carthagena1 #bgb1 #bgg1 #bgi4 ,,castro1 ,,nicolas1 #bfj1 #bfc1 #bhj4 ,,causon1 ,,william1 #aei4 ,,caxatambo1 #beb4 ,,central ,,argentine ,,railway1 #cc4 ,,cerro ,,de ,,pasco1 #aig1 #bja1 #bbg1 #bbi1 #bcb1 #bee1 #beh4 ,,chain-,,and-,,bucket1 #ab4 ,,chain-,,pump1 #bih1 #cag4 ,,chaper1 ,mr41 #ahh4 ,,chili1 #bdg1 #bdi4 ,,circular ,,motion1 #bid4 ,,clark1 ,,henry1 #gh1 #aai1 #ada1 #aef4 ,,clay ,,mill1 #a4 ,,coalbrookdale1 #b1 #c1 #e1 #ach4 ,,coal-,,lifting ,,engine1 #cfe1 #cfh1 #cgj4 ,,cochrane1 ,lord1 #bhb1 #bhd4 ,,collins1 ,mr41 #ie4 ,,colombia1 #beb4 ,,common-,,road ,,locomotive1 #aaj1 #abc1 #abf1 #aeh1 #cjj1 #cgg4 ,,competition1 #ba1 #cc1 #hh1 #ib1 #abb1 #acb1 #ada1 #aej1 #aef1 #cgd1 #cie4 ,,compound ,,engine1 #ajc1 #cad1 #chf4 ,,comptroller ,,of ,,the ,,navy1 #cdb4 ,,condenser1 #acd4 ,,cooking ,,by ,,steam1 #cfh4 ,,cook',s ,,kitchen1 #adi4 ,,copiapo1 #bea4 ,,copper-,,ore ,,furnace1 #aj4 ,,coralillo1 #bfb4 ,,cordillera1 #bfb4 ,,cost-,,all-,,lost-,,all1 #gc4 ,,cost ,,of ,,engine1 #e1 #ae1 #cd1 #cg1 #dc1 #de1 #df1 #di1 #fa1 #gc1 #hc1 #abb1 #ade1 #adi4 ,,costa ,,rica1 #beb1 #bfj1 #bfd1 #bgh4 ,,cowie1 ,mr41 #hg4 ,,crichton1 ,mr4 ,,alexander1 #cei4 ,,cylinder1 #ai1 #bh1 #ci1 #fj1 #fg1 #adh1 #baj4 ,,cylinder-,,case1 #cgj1 #cgg4 ,,cylindrical ,,boiler1 #fj1 #fg1 #fi1 #ga1 #gd1 #ib1 #ajb1 #aji1 #aai1 #abc1 #ach1 #adj1 #ade1 #adh1 #aef1 #afc1 #afi1 #ahf1 #baj1 #bbg1 #cjj1 #cjh1 #cdd4 ,d4 ,,daniel1 ,mr41 #adb4 ,,darlington1 ,earl of1 #cij4 ,,dartford1 #cic4 ,,davey1 ,captain ,,john1 #aah4 ,,davey1 ,captain ,,william1 #hc1 #aja1 #abd4 ,,davies1 ,mr41 #hf4 ,,day1 ,mr41 #bae4 ,,dedunstanville1 ,lord1 #i1 #ah1 #ba1 #ci1 #ec4 ,,denison1 ,mr41 #cij4 ,,derbyshire1 #c4 ,,dixon1 ,mr41 #abh4 ,,doble1 ,mr41 #ch4 ,,dolcoath1 #a1 #h1 #aj1 #cb1 #dj1 #aae1 #aaf1 #aai1 #ada1 #adc1 #ade1 #adg1 #aej1 #aec1 #aee1 #aeg1 #afb1 #afh1 #aga1 #age1 #ahj1 #aid1 #bej1 #cjg1 #caf1 #cba4 ,,domingo ,,gonzales ,,de ,,casta,,eda1 #bcd4 ,,dredger1 #aaj1 #adc1 #aej1 #big1 #cce4 ,,driving ,,wheels1 #ef4 ,,dundonald1 ,lord1 #aaa1 #bdi1 #bhb1 #bhf4 ,,duty ,,of ,,engines1 #gc1 #hc1 #if1 #ii1 #aje1 #ajh1 #aji1 #aag1 #abd1 #abh1 #adb1 #aeg1 #afc1 #aff1 #agj1 #age1 #agh1 #aha1 #ahc1 #ahg1 #aia1 #bje1 #bgg1 #bij1 #cje1 #cjh1 #caj1 #cbg1 #ccc1 #cgd4 ,e4 ,,easthope1 ,mr41 #cij4 ,,eccentric1 #bjh4 ',,echo1' ,,steamer1 #cef1 #cfj4 ,,edmonds1 ,mr4 ,,richard1 #ajg1 #ahc1 #bch1 #bde1 #cje4 ,,edmonds1 ,mr4 ,,thomas1 #bfi4 ,,edwards1 ,mr41 #ahh4 ,,empson1 ,mr41 #bgi4 ',,encyclop,,dia ,,britannica1' #ahb4 ,,erskine1 ,mr41 #acj1 #cjc4 ,,essential ,,oil1 #bjb4 ,,exeter ,,bridge1 #bc1 #bh1 #ed4 ,,expansion1 #ai1 #fi1 #he1 #ia1 #ajj1 #aag1 #abh1 #acb1 #adc1 #ade1 #adh1 #agi1 #ahe1 #bje1 #baj1 #cbe1 #ccj1 #ceb1 #cfa1 #cgf1 #chb4 ,,explosion1 #aec4 ,f4 ,,fairbairn1 ,mr4 ,,james1 #bgc4 ,,fairbairn1 ,sir ,,william1 #ceh4 ,,falmouth1 #bg4 ,,farey1 ,mr41 #ahj1 #cbc4 ,,faucett and ,co41 #cge4 ,,feed-,,pole1 #aei4 ,,feed-,,water1 #ci1 #cfi1 #cgc1 #cgf4 ,,fire-,,arms1 #bed4 ,,fire-,,bars1 #bj4 ,,fire-,,engine1 #acd4 ,,follett1 ,sir ,,william1 #ceh4 ,,four-,,way ,,cock1 #ai1 #bi1 #fj1 #fg1 #aec4 ,,foxes1 ,messrs41 #bb1 #bg1 #cj1 #ee1 #hh1 #abd1 #aea1 #aec4 ,,france1 #cfe4 ,g4 ,,galloway1 ,mr41 #aj4 ,,gamboa1 #bhj4 ,,gear-,,work1 #afj4 ,,geological ,,society1 #bde4 ',,george ,,and ,,vulture1' #cff4 ,,gerard1 ,mr41 #bee1 #bfb1 #bfe1 #bfi1 #bga1 #bgi1 #bhj1 #bhb1 #bhf1 #bhg4 ,,gibbs1 ,mr41 #abi4 ,,gilbert1 ,,davies1 #aj1 #bc1 #hc1 #ic1 #aaf1 #aah1 #aff1 #ahc1 #cjd1 #cjg1 #cjh1 #cac1 #cai1 #cch1 #cfc1 #cgd1 #chh4 ,,gittins1 ,mr41 #bfi4 ,,glanville1 ,captain1 #aai1 #adj1 #aei4 ,,globular ,,boiler1 #aai1 #abd4 ,,gossett1 ,colonel1 #bhf4 ,,gould1 ,mr41 #h1 #bg4 ,,government1 #aed1 #ahc1 #caa1 #cch1 #chh4 ,,governor1 #ba4 ,,green1 ,mr41 #bc1 #bi4 ,,greenwich1 #abd4 ,,gregor1 ,captain1 #cae4 ,,greytown1 #bga4 ,,gribble1 #aei1 #agf4 ,,grinding ,,engine1 #b4 ,,grip1 #ef4 ,,grist ,,mill1 #ai4 ,,grose1 ,captain ,,samuel1 #a1 #fj1 #fi1 #aja1 #ajb1 #aaa1 #agf1 #agh1 #ahh1 #cba4 ,,guayaquil1 #beb4 ,,guildhall1 #cfe4 ,,gun-,,carriage1 #bgh1 #bhb1 #bhd1 #bhf4 ,,gundry1 ,mr41 #ag4 ,,gunnery1 #bhi4 ,h4 ,,haarlem ,,lake1 #cjb4 ,,hall and ,,sons1 #bhc1 #cic4 ,,hall1 ,mr41 #big4 ,,hall1 ,mr4 ,b4 ,n41 #bgc4 ,,hall',s ,,condenser1 #ai1 #cbb1 #chc4 ,,halse1 ,mr41 #ag4 ,,hardy1 ,sir ,t4 ,h41 #cci4 ,,harris1 ,mr41 #adb1 #aeb4 ,,harrow ,,by ,,steam1 #dj1 #dc1 #eh4 ,,harvey1 ,mr4 ,,henry1 #bc1 #dh1 #eb1 #fd1 #hh1 #aja1 #aeb1 #aed1 #ahh1 #ahi1 #beg1 #bih1 #cja1 #cjb1 #cjc1 #cef1 #cfa1 #che4 ,,harvey1 ,mr4 ,,nicholas1 #bie4 ,,hawkins1 ,mr41 #cie4 ,,hawkins1 ,sir ,c41 #af1 #cf1 #ci1 #dj1 #de1 #dg1 #ed1 #fa1 #aga4 ,,hayle ,,harbour1 #cce4 ,,hazeldine1 ,mr41 #eb1 #ff1 #aea1 #bjd1 #bae4 ,,hearse-,,boiler1 #aee1 #aeg1 #afc1 #ahj1 #cjh4 ,,heat ,,lost1 #g4 ,,heating ,,apparatus1 #cfc4 ,,henwood1 ,mr41 #ahj1 #ahe1 #bde1 #cfj1 #chf4 ,,herland1 #ca1 #gd1 #hc1 #hg1 #ia1 #if1 #ii1 #aja1 #aje1 #aad1 #aah1 #cjh1 #caj4 ,,high ,,pressure1 #ai1 #aji1 #aai1 #adh1 #aej1 #aih1 #bga1 #caj1 #cgf4 ,,hill1 ,mr41 #acc4 ,,hodge1 ,captain1 #bdf1 #bdi4 ,,holland1 #aaj1 #bif1 #bii1 #cag1 #ccc1 #cfi4 ,,holman1 ,mr41 #hg4 ,,homfray1 ,mr41 #d1 #abe1 #abh1 #acb1 #acd1 #aci1 #adj4 ,,horizontal ,,cylinder1 #ai1 #bh4 ,,hornblower1 #aag1 #agj4 ,,horse-,,power1 #cf1 #db4 ,,hot ,,blast1 #aa4 ,,hot-,,house1 #acc4 ,,hot-,,house ,,store1 #cfc4 ,,howard1 ,mr41 #cij4 ,,hume1 ,,joseph1 #cij4 ,,husband1 ,mr41 #che4 ,,hydraulic ,,crane1 #che4 ,i4 ,,ice ,,making1 #bid4 ,,illness1 #cfc1 #chh4 ,,illogan1 #bbh4 ,,incline1 #bfg1 #bfi4 ,,injection1 #ai1 #cbd4 ,,invoice1 #bbj4 ,,iron ,,furnace1 #h4 ,,iron ,,ships1 #bhf1 #big1 #bii1 #cag4 ,j4 ,,jamaica1 #bgg4 ,,jasper1 ,mr41 #ci1 #ff4 ,,jeffry1 ,,richard1 #aei1 #agf4 ,,jenkin1 ,mr41 #hc1 #aah1 #aff4 ,,joaquin ,,de ,,la ,,pezula1 #bcc1 #bcg4 ,,johnstone1 ,captain1 #cge4 ,,jos ,,gonzales ,,de ,,prada1 #bcf4 ,,jos ,,lago ,y ,,lemus1 #bcd4 ,,juan ,,mora ,,river1 #bff4 ,,judson1 ,mr41 #bdg4 ,k4 ,,kendal1 ,mr41 #ci1 #ei4 ,,kenny1 ,captain1 #ajg1 #bbh1 #bca4 ,,king1 ,captain1 #cef1 #cfa4 ,l4 ',,la ,,belle ,,machine1' #ahi4 ,,law ,,proceedings1 #adh1 #aej4 ,,lean1 ,mr41 #aag1 #afj1 #afd4 ,,lean1 ,mr4 ,,john1 #cag4 ,,legassack1 #ajb4 ,,leith1 ,captain1 #bcj4 ,,letters1--,edmonds1 ,mr4 ,richard1 #ajf2 #bbh1 ,aug4 #bj1 #ahag2 #cje1 ,nov4 #g1 #ahbg2 #cje1 ,jan4 #bd1 #ahbh2 #cjf1 ,jan4 #ab1 #ahec2 ,fairbairn1 ,mr4 ,james1 #bgb1 ,nov4 #bg1 #ahfd2 ,gerard1 ,mr41 #bgc1 ,nov4 #ag1 #ahbg2 #bhj1 ,jan4 #ac1 #ahbf2 #bhf1 ,feb4 #ba1 #ahbh2 ,gilbert1 ,davies1 #aj1 ,jan4 #bj1 #ahaa2 #ic1 ,feb4 #ae1 #ahaf2 #cab1 ,dec4 #be1 #ahca2 #chh1 ,dec4 #bf1 #ahca2 ,hall1 ,mr4 ,b4 ,n41 #bgc1 ,dec4 #af1 #ahfd2 ,harvey1 ,mr41 #bc1 ,nov4 #bf1 #ahab2 #aja1 ,april #ah1 #ahaf2 #aed1 ,aug4 #bf1 #ahaj2 ,hawkins1 ,sir ,c41 #ci1 ,march #ai1 #ahab2 ,homfray1 ,mr41 #acg1 ,dec4 #bf1 #ahjd2 #aci1 ,jan4 #b1 #ahje2 ,liddell1 ,captain1 #bej1 ,nov4 #c1 #ahfi2 ,smith1 ,mr4 ,t41 #fg1 ,march #bf1 #ahgj2 ,thomas1 ,captain ,c41 #afb1 ,march #bi1 #aheh2 ,trethuoy1 ,mr4 ,w41 #fh1 ,may #ag1 #ahgb2 ,trevithick1 ,richard1 #b1 ,sept4 #bc1 #ahjd2 #f1 ,jan4 #ac1 #ahaa2 #ab1 ,march #e1 #ahab2 #af1 ,dec4 #e1 #ahab2 #af1 ,april #bh1 #ahab2 #ah1 ,dec4 #g1 #ahab2 #bb1 ,nov4 #h1 #ahab2 #bd1 ,jan4 #bi1 #ahac2 #bg1 ,feb4 #d1 #ahac2 #bh1 ,feb4 #d1 #ahac2 #cj1 ,march #ad1 #ahad2 #ca1 ,dec4 #i1 #ahae2 #cc1 ,aug4 #ai1 #ahac2 #cc1 ,march #h1 #ahaf2 #cf1 ,feb4 #ac1 #ahab2 #da1 ,april #bf1 #ahab2 #de1 ,may #a1 #ahab2 #dg1 ,june #ac1 #ahab2 #di1 ,june #ag1 #ahab2 #ej1 ,july #e1 #ahab2 #ea1 ,oct4 #af1 #ahab2 #ed1 ,jan4 #bf1 #ahac2 #ei1 ,jan4 #bf1 #ahac2 #fa1 ,march #ae1 #ahac2 #fa1 ,aug4 #ai1 #ahac2 #hj1 ,july #h1 #ahae2 #hf1 ,sept4 #ab1 #ahae2 #hg1 ,sept4 #bi1 #ahae2 #hh1 ,dec4 #ac1 #ahae2 #hi1 ,dec4 #bc1 #ahae2 #ia1 ,feb4 #aa1 #ahaf2 #id1 ,march #h1 #ahaf2 #if1 ,march #h1 #ahaf2 #ih1 ,march #g1 #ahaf2 #ii1 ,april #b1 #ahaf2 #abd1 ,oct4 #a1 #ahjc2 #abh1 ,jan4 #e1 #ahjd2 #acb1 ,july #e1 #ahjd2 #ada1 ,feb4 #ah1 #ahjf2 #ade1 ,march #d1 #ahjf2 #adf1 ,march #ba1 #ahjf2 #aga1 ,march #aj1 #ahab2 #agc1 ,march #bg1 #ahac2 #aic1 ,may #bj1 #ahac2 #aih1 ,may #bb1 #ahac2 #aii1 ,june #b1 #ahac2 #bjj1 ,june #h1 #ahac2 #bja1 ,june #aa1 #ahac2 #bjb1 ,june #ai1 #ahac2 #bjc1 ,june #bc1 #ahac2 #bjd1 ,sept4 #d1 #ahac2 #bje1 ,sept4 #g1 #ahac2 #bjf1 ,sept4 #bb1 #ahac2 #bjf1 ,oct4 #a1 #ahac2 #bjg1 ,oct4 #aa1 #ahac2 #bji1 ,oct4 #bc1 #ahac2 #bab1 ,dec4 #bh1 #ahac2 #bab1 ,march #d1 #ahad2 #bdj1 ,feb4 #ae1 #ahag2 #bdc1 ,nov4 #ahag2 #bea1 #bgg1 ,nov4 #ae1 #ahbg2 #bha1 ,jan4 #bd1 #ahbh2 #bhf1 ,feb4 #ba1 #ahbh2 #bhi1 ,april #ai1 #ahcj2 #bib1 ,june #ah1 #ahbh2 #bid1 ,june #bi1 #ahbh2 #bie1 ,july #ca1 #ahbh2 #cjc1 ,sept4 #ad1 #ahbi2 #cje1 ,jan4 #bd1 #ahbh2 #cjf1 ,dec4 #bj1 #ahbg2 #caa1 ,dec4 #bd1 #ahca2 #cae1 ,dec4 #ad1 #ahbh2 #cbc1 ,dec4 #cj1 #ahbh2 #ccb1 ,july #bg1 #ahbi2 #cce1 ,nov4 #e1 #ahbi2 #ccf1 ,nov4 #ad1 #ahbi2 #cci1 ,aug4 #ai1 #ahcj2 #cfc1 ,march #a1 #ahcj2 #cfh1 ,jan4 #bd1 #ahbi2 #cgb1 ,june #aj1 #ahcj2 ,vivian1 ,captain ,a41 #aej1 ,may #cj1 #ahjf2 ,williams1 ,mr4 ,m41 #aaa1 ,jan4 #e1 #ahec2 ,williams1 ,messrs41 #cjd1 ,nov4 #ad1 #ahbj4 ,,liberality1 #di4 ,,liberty1 ,,wheal1 #ci4 ,,liddell1 ,captain1 #bej4 ,,lima1 #ca1 #cb1 #fd1 #hj1 #aie1 #bjf1 #bag1 #bah1 #bbd1 #bbf1 #bdj1 #bdg1 #bdi1 #bga4 ,,linthorn1 ,mr41 #bib4 ,,locomotive1 #bc1 #bf1 #bg1 #ci1 #da1 #dc1 #dh1 #ej1 #abf1 #acc1 #bjf1 #bag1 #bga1 #cgd1 #cgi1 #chg1 #chh4 ,,logan1 ,dr41 #dj4 ,,london ,,engine1 #e4 ,,losh1 ,mr41 #ie4 ,,low ,,pressure1 #gf1 #adj1 #adh1 #aeg1 #agi1 #ahj1 #aib1 #cie4 ,,lowe1 ,mr41 #bgg4 ,,lowndes1 ,lord1 #bhg4 ,m4 ,,machuca1 #bfb4 ,,magdalena1 #bgb4 ,,man ,,and ,,his ,,man1 #cfa4 ,,manchester1 #c1 #ach1 #aci4 ,,man',s ,,power1 #db4 ,,marazion1 #ahj4 ,,marratt1 ,mr41 #abi4 ,,matina1 #bfe1 #bfg4 ,,maudslay1 ,mr41 #cge4 ,,mellinear ,,mine1 #ge4 ,,melville1 ,lord1 #bd1 #cfa4 ,,meux',s ,,brewery1 #aaa4 ,,miers1 ,mr41 #bdg4 ,,mills1 ,mr41 #cci1 #cge4 ,,mint ,,engine1 #cb1 #bja1 #bji1 #bag1 #bbg1 #bci1 #bdj1 #bdc1 #bdg4 ,,mitchell1 ,mr41 #acg4 ,,model1 #aig4 ,,momentum1 #bj1 #he1 #ia1 #ade1 #adi4 ,,mont ,,cenis1 #bf1 #bic4 ,,montelegre1 ,mr41 #bfi4 ,,montelegre ,,river1 #bff1 #bgi1 #bhj4 ,,moore1 ,dr41 #cd4 ,,morley1 ,earl of1 #cij4 ,,moyle1 ,captain ,m41 #cjg4 ,,mule-,,power1 #de1 #dg1 #bja4 ,,murdoch1 #aje1 #aah1 #abe1 #abf4 ,n4 ,,nankivill1 ,mr41 #ch4 ,,navy ,,board1 #ag1 #da1 #dg1 #cgb4 ,,neath ,,abbey1 #aed1 #aii4 ,,nelson1 ,lord1 #aba4 ,,neville1 ,mr41 #aeg1 #ahg4 ,,new ,,steam ,,navigation ,,company1 #chc4 ,,newcastle-,,upon-,,tyne1 #c4 ,,newcomen1 #hc1 #aad1 #aba1 #aeg1 #age1 #baa1 #cjj1 #cai1 #cbh4 ,,nicaragua ,,lake1 #bfi4 ,,norfolk1 ,duke of1 #cij4 ,,number ,,of ,,engines1 #ad1 #adh4 ,o4 ,,oats1 ,,james1 #aaa4 ,,odgers1 ,captain1 #ih4 ,,open-,,top ,,cylinders1 #ai1 #fj1 #bjh1 #baj1 #baa1 #cjj1 #cfc4 ,,oval ,,tube1 #ba1 #aec4 ,p4 ,,paddle-,,wheel1 #chd4 ,,padre ,,arias ,,mine1 #bfb4 ,,padstow ,,engine1 #ah1 #bg1 #bi4 ,,page1 ,mr41 #ih1 #ii1 #bab1 #bad1 #bca1 #bda4 ,,palmer1 ,general1 #cij4 ,,pape1 ,mrs41 #ff4 ,,parallel ,,motion1 #ci4 ,,patent ,,laws1 #dh1 #abh1 #cjd4 ,,patents1 #cdc of #ahca2 #cff of #ahca2 #cgf of #ahcb4 ,,paynter1 ,mr41 #bhj4 ,,penponds1 #aeh4 ,,penydarran1 #acb4 ,,perceval1 ,mr41 #ajh4 ,,perrier1 ,mr41 #ahh4 ,,peru1 #baj1 #bba1 #beb4 ,,petition ,,to ,,parliament1 #cjf1 #cgd1 #chh4 ,,phillip1 ,mr41 #hi1 #if1 #ii4 ,,phillips1 ,,henry1 #ij4 ,,pickwood1 ,mr41 #dg4 ,,pinneys and ,,ames1 #cc1 #di1 #ej1 #ea1 #fc4 ,,pinto1 ,,don ,,antonio1 #bhj4 ,,ploughing ,,by ,,steam1 #dj1 #ed1 #fg4 ,,plummer1 ,,barham1 and ,co41 #di4 ,,plunger-,,pole ,,pump1 #aai1 #aih4 ,,plymouth ,,breakwater1 #bb1 #bc1 #be1 #bg1 #bi1 #cj1 #ed1 #aie4 ,,plymouth ,,dockyard1 #cfa4 ,,pneumatic ,,elevator1 #cib4 ,,poldice1 #ajc4 ,,pole-,,engine1 #ca1 #fi1 #hj1 #hc1 #ij1 #ib1 #ii1 #ajb1 #agf4 ,,pole1 ,professor1 #agi4 ,,pooly1 ,,william1 #aeh4 ,,population1 #dd1 #bfe4 ,,portable ,,engine1 #a1 #e1 #ag1 #bb1 #ci1 #ej1 #ed1 #agj1 #bbj1 #cji1 #cfh1 #cgj1 #cgd4 ,,power ,,of ,,engine1 #ad1 #bg1 #db1 #gb1 #gf1 #hj1 #hf1 #ajj1 #aae1 #aba1 #adc1 #adh1 #baj1 #baa1 #ccc4 ,,praed1 ,mr41 #ag1 #dh1 #cce4 ,,price1 ,mr4 ,,joseph1 #if4 ,,price1 ,sir ,,rose1 #fd4 ,,proney1 ,mr41 #ahi4 ,,puffer-,,engine1 #a1 #bf1 #cb1 #fj1 #gd1 #ia1 #ajb1 #acf1 #adj1 #aej1 #aed1 #baj4 ,,pumping ,,engine1 #aca1 #adh1 #aej1 #aga1 #ahb1 #ahi1 #aih1 #bjg1 #baa1 #bag1 #bbj1 #bdj1 #beg4 ,,pumps1 #aai1 #abd1 #aih1 #bjg1 #baa1 #ccc4 ,,punta ,,de ,,arenas1 #bfj1 #bfg4 ,q4 ,,quarrying1 #bb1 #bf4 ,,quebrada-,,honda1 #bfb4 ,r4 ,,railway1 #adh4 ',,ranee' ,,locomotive1 #chg4 ,,rastrick1 ,mr41 #ah1 #ed1 #fc1 #ff1 #gc1 #hg1 #aie1 #bjj1 #bjd1 #bab4 ,,rawlings1 ,mr41 #fb4 ,,rees',s ,,cyclop,,dia1 #aha4 ,,reform ,,column1 #cij4 ,,rennie1 ,mr41 #bd1 #bh1 #ca1 #aeg1 #aha1 #ahd1 #ahg1 #cbj1 #cci1 #cef1 #ceh1 #cgb1 #cha4 ,,reynolds1 ,mr41 #aj1 #aea4 ,,rhine ,,river1 #bie1 #big1 #cjb4 ,,rice1 ,,spring1 #caa1 #chh4 ,,richards1 ,mr41 #ai1 #ef4 ,,ridley1 ,sir ,,matthew1 #chh4 ,,robarts1 ,mr41 #cij4 ,,roberts1 ,mr41 #ch4 ,,robinson and ,,buchanan1 #ae1 #af4 ,,rock ,,boring1 #aaj1 #bjf4 ',,rocket1' #ced4 ,,roland1 ,mr41 #aif1 #bbi4 ,,rolling ,,mill1 #d1 #acb1 #acg1 #bji1 #bbj4 ,,rotterdam1 #bie4 ,,rowe1 ,,george1 #afc4 ,,rowe1 ,mr41 #bca4 ,s4 ,,safety-,,plug1 #abf4 ,,st4 ,,agnes ,,head1 #ei1 #aga4 ,,st4 ,,aubyn1 ,sir ,,john1 #cce4 ,,st4 ,,ives1 #h1 #af1 #cjb4 ,,saltram ,,stream1 #ajb4 ,,san ,,jos1 #bfg4 ,,san ,,jos ,,river1 #bff4 ,,san ,,juan ,,de ,,nicaragua1 #bfe1 #bfi1 #bga4 ,,san ,,martin1 #bdi4 ,,sandys1 ,,carne1 and ,,vivian1 #cjc4 ',,sanspareil1' #bjd4 ,,santa ,,rosa1 #bcg4 ,,saunders1 ,,james1 #bca4 ,,savery1 #aad1 #aag1 #cai4 ,,sawing ,,by ,,steam1 #da4 ,,screw-,,bit1 #bg4 ,,screw-,,power1 #bic4 ,,screw-,,propeller1 #fg1 #chd4 ,,serapique1 #bfe1 #bff1 #bhj4 ,,shammal ,,engine1 #aba1 #aeh1 #aff1 #agg4 ,,sharratt1 ,mr41 #abh4 ,,sheffield1 ,mr41 #i4 ,,ships ,,of ,,iron1 #bhf4 ,,silver ,,statue1 #bdd4 ,,sims1 ,mr41 #hg1 #ajb1 #ajf1 #aej1 #aec1 #agf1 #cjd4 ,,sinclair1 ,sir ,,john1 #ag1 #dj1 #da1 #dg4 ,,sing1 ,mr41 #ff4 ,,smelting ,,furnace1 #h4 ,,smiles1 ,mr41 #cec4 ,,smith1 ,mr41 #ie1 #bda4 ,,smith1 ,mr4 ,,thomas1 #ff1 #fg4 ,,smoke ,,burner1 #bj4 ,,soho1 #agi4 ,,somerset1 ,duke of1 #cij4 ,,south ,,america1 #ahh1 #aie1 #bbe1 #bbg1 #bfj1 #cji4 ,,spade ,,by ,,steam1 #dj1 #eh4 ,,spanish ,,government1 #bje1 #bed4 ,,spanish ,,merchants1 #b4 ,,spring ,,steelyard1 #cga4 ,,steam ,,agriculture1 #da1 #dc1 #eh4 ,,boat1 #ag1 #da1 #cbi1 #ccg1 #cef1 #cei1 #cge1 #cgh4 ,,steam ,,crane1 #bc1 #bg4 ,,cushion1 #hd4 ,,mash-,,tub1 #ad4 ,,navigation ,,company1 #bie4 ,,paddle1 #cfi4 ,,plough1 #dc1 #eh4 ,,steam ,,pressure1 #a1 #ad1 #bj1 #cb1 #cd1 #fi1 #gd1 #hf1 #ia1 #ajj1 #ajb1 #aji1 #aba1 #abc1 #abf1 #adb1 #adi1 #aec1 #aee1 #agi1 #ahd1 #aib1 #baj1 #cji1 #ccj1 #ccg1 #ceh1 #chf4 ,,steam ,,stone-,,boring1 #be1 #bg1 #bi1 #cj4 ,,users' ,,association1 #ceh4 ,,stephenson1 #bgb1 #bgc1 #bgi1 #bhc1 #cec4 ,,stevenson1 ,mr4 ,w4 ,b41 #bdg4 ,,stone-,,borer1 #bb1 #bd1 #bg4 ,,stone-,,crusher1 #a4 ,,stone-,,splitter1 #be4 ,,stourbridge1 #acb4 ,,stray ,,park1 #aei1 #aff1 #afi1 #age1 #agg1 #ahc4 ,,strength1 #ij4 ,,strokes1 #bj1 #cb1 #cf1 #hb1 #ia1 #ih1 #ajj1 #baj4 ,,stuffing ,,box1 #ca1 #gi1 #hd4 ,,sugar-,,boiling1 #c4 ,,sugar ,,mill1 #b1 #ej4 ,,superheating ,,steam1 #bij1 #cae1 #cbd1 #ccj1 #cgf4 ,,surface-,,air ,,condenser1 #ccc1 #cce1 #cci1 #cda1 #cdc1 #cgd4 ,,surface-,,water ,,condenser1 #ai1 #caf1 #cbb1 #cbd1 #cbi1 #ccb1 #cce1 #cch1 #cda1 #cdc1 #cgd4 ,,swaine1 ,,charles1 #aai4 ,,sycombe1 ,mr41 #bcb4 ,,symonds1 ,captain1 #cci4 ',,syria1' ,,steamboat1 #chd4 ,t4 ,,tanks1 #chh4 ',,tasmania1' ,,steamboat1 #cad4 ,,taylor1 ,mr41 #aah1 #ahj4 ,,teague1 ,captain1 #aig1 #aii1 #bbi4 ,,telford1 ,mr41 #ccf4 ,,thomas1 ,captain ,,charles1 #a1 #gd1 #afb4 ,,thomas1 ,captain ,,jacob1 #aeg4 ,,thomas1 ,captain ,,josiah1 #afg4 ,,thompson1 ,mr41 #chh4 ,,thorne1 ,dr41 #bdf4 ,,thrashing ,,engine1 #ag1 #ba1 #cf1 #ch1 #dj1 #db1 #ed1 #fa1 #fd1 #fh4 ,,tilly1 ,captain1 #bbi4 ,,tin ,,croft1 #agj1 #agc4 ,,tormentor1 #eh4 ,,treasury1 ,,wheal1 #aeb4 ,,trecothick1 ,mr41 #dg1 #ej4 ,,treskerby1 #ajb1 #aje1 #ajg1 #agf1 #cje4 ,,trethuoy1 ,mr4 ,,william1 #fh4 ,,trevarthen1 ,captain1 #bac1 #bcj4 ,,trevithick1 ,r41 ,jun41 #aeh4 ,,trevithick1 ,sen41 #aae4 ,,trevithick1 ,mrs41 #a4 ,,trewithen1 #ch1 #fh4 ,,trinity ,,board1 #adc1 #aej4 ,,tubular ,,boiler1 #cb1 #aae1 #aai1 #aec1 #bia1 #cjh1 #cbe1 #cci1 #cdd1 #cei1 #cgf1 #chg4 ,,tyack1 ,mr4 ,,john1 #bie4 ,u4 ,,united ,,mines1 #cjd4 ,,upright ,,boiler1 #da1 #fj1 #bij1 #ccb1 #cci4 ,,uville1 ,mr41 #cb1 #fc1 #aif1 #bjj1 #bjd1 #bjh1 #bab1 #bad1 #bag1 #bba1 #bbd1 #bbg1 #bbi1 #bcf1 #bdj1 #bdd1 #bde4 ,v4 ,,vacuum1 #fi1 #aeg1 #cbe4 ,,valley ,,puffer1 #aai1 #adb4 ,,valves1 #afj4 ,,viceroy1 #bbf1 #bea1 #bei4 ,,vivian1 ,captain ,,andrew1 #eb1 #hh1 #if1 #aaf1 #abe1 #ach1 #adj1 #ada1 #aeb1 #aed1 #afe1 #cjf4 ,,vivian1 ,captain ,,henry1 #ij1 #bae1 #bcj1 #bdj4 ,,vivian1 ,captain ,,joseph1 #aja1 #adb4 ,captain ,,nicholas1 #aeg1 #ahg4 ,,henry1 #fj4 ,mr4 ,,simon1 #aeb4 ,w4 ,,ward1 ,mr41 #cfa4 ,,warren1 ,mr41 #ff4 ,,warsop1 ,mr41 #aj4 ,,water-,,pressure ,,engine1 #ac1 #bic1 #caj4 ,,water-,,propeller1 #cgh4 ,,waters1 ,mr41 #bej4 ,,waterwitch ,,company1 #chc4 ,,watkin1 ,sir ,,edward1 #bgc4 ,,watson1 ,mr41 #bdg4 ,,watt1 #ba1 #cc1 #dg1 #ge1 #hj1 #hc1 #hf1 #ib1 #ie1 #ih1 #ajc1 #aje1 #aab1 #aae1 #aah1 #abd1 #abe1 #abf1 #abh1 #aej1 #aef1 #aei1 #afc1 #agj1 #age1 #agh1 #ahj1 #ahc1 #ahi1 #aia1 #aif1 #baa1 #bbd1 #bcj1 #bij1 #cjj1 #cjh1 #cab1 #cai1 #cbc1 #cbh1 #cca1 #ceb1 #cgj1 #cgd1 #chf1 #chh1 #cie4 ,,welsh ,,locomotive1 #db1 #fh4 ,,west ,,india ,,docks1 #c1 #acc4 ,,west ,,india ,,engine1 #ci1 #de1 #ec1 #fc1 #aie1 #bja4 ,,west1 ,,john1 #afj4 ,,william1 #aeh1 #afc4 ,,wheal1 ,,abraham1 #adh1 #aea1 #aec4 ,,alfred1 #ai1 #ed1 #ajc1 #aje1 #ajf4 ,,wheal ,,clowance1 #aec4 ,,concord1 #ajc4 ,,damsel1 #ajc1 #cbg4 ,,gens1 #aag1 #aah1 #aee1 #aei1 #afi1 #agg4 ,,wheal ,,jewel1 #aej4 ,,kitty1 #aec4 ,,liberty1 #aga4 ,,lushington1 #ajc4 ,,prosper1 #fi1 #hd1 #ajf1 #aga4 ,,regent1 #ajb4 ,,seal-,,hole1 #agj1 #cfj4 ,,towan1 #aeg1 #agh1 #ahe1 #caf1 #cbg1 #cca1 #cfj1 #cfi4 ,,wheal ,,treasure1 #ajb4 ,,vor1 #hc1 #cbg4 ,,whims1 #ag1 #cb1 #ci1 #fj1 #aai1 #abh1 #ada1 #aej1 #aec1 #agb4 ,,whitehead1 ,mr41 #aci4 ',,wildman1' ,,ship1 #bag4 ,,williams1 ,messrs41 #bb1 #hh1 #ajf1 #aji1 #abd1 #aej1 #aec1 #ahd1 #bha1 #bhc1 #cjd4 ,,williams1 ,,william1 #bbj4 ,,wilson1 ,mr41 #chf4 ,,winding ,,engine1 #b1 #bja1 #bjh1 #bag1 #bbj1 #bdj4 ,,windmill1 #bif4 ,,wollaston1 ,dr41 #bic4 ,,wood1 ,mr41 #d4 ,,woolf1 ,,arthur1 #hj1 #hc1 #hf1 #ib1 #if1 #aaa1 #ahj1 #ahi1 #caf4 ,,woolwich1 #bhf1 #cce4 ,,worcester1 #acc4 ,y4 ,,yanacancha1 #bch4 ,,yonge1 ,,don1 #bhj4 ,z4 ,,zuyder ,,zee1 #cjb4 ,,london3 ,,printed ,,by ,w4 ,,clowes ,,and ,,sons1 ,,stamford ,,street ,,and ,,charing ,,cross 99 99 99 99 99 99 ,transcriber's note3 ,inconsistencies in spelling and punctuation are as in the original4