,illustration ,,scientific ,,american ,,supplement ,,no4 #ejh ,,new ,,york1 ,,september #bf1 #ahhe ,scientific ,american ,supplement4 ,vol4 ,,xx41 ,no4 #ejh4 ,scientific ,american established #ahde ,scientific ,american ,supplement1 #e a year4 ,scientific ,american and ,supplement1 #g a year4 99 99 99 99 99 ,,table ,,of ,,contents ,,page ,i4 ,,chemistry ,,and ,,metallurgy4--,the ,cowles ,electric ,smelting ,process4 #e figures4 #haac ,on the ,electrical ,furnace and the ,reduction of the ,oxides of ,boron1 ,silicon1 ,aluminum1 and other ,metals by ,carbon4--,by ,,eugene ,h4 ,,cowles1 ,,alfred ,h4 ,,cowles1 and ,,charles ,f4 ,,mabery4 #haab ,chemical ,action of ,light4 #haag ,eutexia4--,cryohydrates4--,eutectic salt alloys and metal alloys4 #haag ,chinoline4 #haah ,method of ,rapid ,estimation of ,urea4 #a figure4 #haah ,assay of ,earthenware ,glaze4 #haab ,,ii4 ,,engineering ,,and ,,mechanics4--,deep ,shafts and ,deep ,mining4 #hajd ,sinking of the ,quievrechain ,working ,shaft4--,numerous figures4 #hajh ,on the ,elementary ,principles of the ,gas ,engine4--,an interesting paper read before the ,gas ,institute by ,mr4 ,,denny ,,lane1 of ,cork1 and discussion following4 #haji ,m4 ,,meizel',s ,reciprocating ,exhauster4 #haab ,automatic ,siphon for ,irrigation4 #a figure4 #haac ,,iii4 ,,electricity1 ,,telegraphy1 ,,etc4--,optical ,telegraphy4-- ,cryptography4--,preservation of ,telegrams4--,the projector in optical telegraphy4--,use of balloons4 #d figures4 #haad ,a ,new ,style of ,submarine ,telegraph4 #d figures4 #haae ,a ,new ,circuit ,cutter4 #b figures4 #haae ,new ,micro ,telephonic ,apparatus4 #e figures4 #haaf ,messrs4 ,kapp and ,crompton's ,measuring ,instruments4 #e figures4 #haaf ,,iv4 ,,geology1 ,,etc4--,permeability of ,sand ,rock4--,by ,f4,h4 ,,newell4 #hajc ,the ,grotto of ,gargas1 in the ,pyrenees4--,paleontological remains found therein4 #b engravings4 #hajc ,remarkable ,wells and ,caverns in ,yucatan4--,by ,,alice ,d4 ,,le ,,plongeon4 #haje ,v4 ,,natural ,,history4--,the ,cabbage ,butterfly and the ,peacock ,butterfly4 #haje ,,vi4 ,,botany ,,and ,,horticulture4--,the ,bhotan ,cypress 7,cupressus torulosa74--,with engraving4 #hajf ,the ,pitcher ,plant4 #hajf ,what is a ,plant8 #hajf ,camellias4--,culture of the same4 #hajf ,arisma ,fimbriatum4--,leaf1 spathe1 and floral details4--,with engraving4 #hajg ,,vii4 ,,miscellaneous4--,striking a ,light with ,bamboo4 #hajg ,experiments in ,memory4 #hajg 99 99 99 99 99 ,,permeability ,,of ,,sand ,,rock4 ,by ,,frederick ,h4 ,,newell1 ,m4,e4 ,among oil producers1 there has been much discussion as to whether the sand rock in which petroleum occurs is of necessity fissured or is still in its original unbroken condition4 ,the earliest and most natural theory1 which for years was indisputed1 and is still given by some textbooks1 was1 that oil wells reached a cavity filled with petroleum4 ,within the past few years1 however1 the opinion has been gaining ground that the oil is stored in the sandrock itself in the minute spaces between the small grains of sand1 not entirely filled by cementing material1 and that crevices holding and conducting oil are rare1 all fissures as a rule being confined to the upper fresh-water bearing rocks of the well4 ,mr4 ,carll1 in ,,iii4 ,pennsylvania ,second ,geological ,survey1 has discussed this subject very fully1 and has made estimates of the quantity of oil that the sand rock can hold and deliver into a well2 also1 ,t4 ,sterry ,hunt1 in his ,chemical and ,geological ,essays1 has made deductions as to the petroleum contained in the ,niagara limestone that outcrops about ,chicago4 ,while the experiments and conclusions of these geologists go to prove that these rocks are capable of holding the oil1 there are on record no facts as to the phenomena of its flow1 other than by capillarity1 through the rock4 ,to obtain some data of the flow of liquids under pressure through certain oil-bearing stones1 series of tests on small pieces were made4 ,these tests were carried on during this spring1 and many results quite unlooked for were obtained4 ,when crude oil1 kerosene1 or water 7river or distilled7 was forced through the specimens1 the pressure being constant1 the rate of flow was variable4 ,at first1 the amount flowing through was large1 then fell off rapidly1 and when the flow had diminished to about one-quarter of its original rate1 the decrease was very slight1 but still continued as long as measurements were made1 in some cases for three weeks4 ,when using crude oil1 this result was not surprising1 for1 as the oil men say1 crude oil paraffines up a rock1 that is1 clogs the minute pores by depositing solid paraffine 7872 but this so-called paraffining took place1 not only with crude oil1 but with refined oil1 and even with distilled water4 ,the only explanation as yet is1 that liquids flowing under pressure through rock on which they exert little or no dissolving effect1 instead of washing out fine particles1 tend to dislodge any minute grains of the stone that may not be firmly held by cement1 and these block up extremely fine and crooked pores in which the fluid is passing4 ,several tests indicated that this blocking up was largely near the surface into which the fluid was passing4 ,when this surface was ground off1 even #a_/ej of an inch1 the flow increased immediately nearly to the original rate4 ,reversing the flow also had the effect of increasing the rate1 even above that of any time previous4 ,with the moderate pressures used--from #b to #hj of mercury--the results show that the rate of flow1 other things being equal1 is directly proportional to the pressure4 ,the porosity of rock is not always a criterion of its permeability2 a very fine grained marble1 containing about #j4f per cent4 cell space1 transmitted water and oil more freely than a shale that would hold #d per cent4 of its bulk of water4 ,if the above conclusions hold on a large scale as on the small1 they may aid in explaining the diminished flow of oil wells4 ,not only will the flow lessen from reduced gas pressure1 but the passages in the rock become less able to allow the oil to flow through4 ,the increase in flow following the explosion of large shots in a sand rock may be due not only to fissuring of the rock1 but to temporary reversal of the pressure1 the force of the explosive tending to drive the oil back for an instant4 ,the large shots now used 7up to #bjj quarts1 or say #ffj pounds of nitroglycerine7 must exert some influence of this kind1 especially when held down by #ejj feet of liquid tamping4 ,in the course of these tests1 it was noticed that fresh water has a more energetic disintegrating action on the shales and clay than on salt water4 ,this may furnish a reason for the fact1 noticed by the oil men1 that fresh water has a much more injurious effect than salt in clogging a well4 ,no oil-bearing sand rock is free from lamin of shale1 and when fresh water gets down into the sand1 the water must1 as the experiments show1 rapidly break up the shale1 setting free fine particles1 which soon are driven along into the minute interstices of the sand rock1 plastering it up and injuring the well4--,engineering and ,mining ,journal4 99 99 99 99 99 ,,the ,,grotto ,,of ,,gargas4 ,the grotto of ,gargas is located in ,mount ,tibiran about three hundred yards above the level of the valley1 and about two miles southeast of the village of ,aventignan4 ,access to it is easy1 since a road made by ,mr4 ,borderes in #ahhd allows carriages to reach its entrance4 ,this grotto is one of the most beautiful in the ,pyrenees1 and presents to the visitor a succession of vast halls with roofs that are curved like a dome1 or are in the form of an ogive1 or are as flat as a ceiling4 ,it is easy to explore these halls1 for the floor is covered with a thick stalagmitic stratum1 and is not irregular as in the majority of large caves4 ,illustration3 ,,fig4 #a4--,,section ,,of ,,the ,,grotto ,,of ,,gargas4 ,upon entering through the iron gate at the mouth of the grotto1 one finds himself in ,bear ,hall1 wherein a strange calcareous concretion offers the form of the carnivorous animal after which the room is named4 ,this chamber is about #hj feet in width by #ih in length4 ,we first descend a slope formed of earth and debris mostly derived from the outside4 ,this slope1 in which are cut several steps1 rests upon a hard1 compact1 and crystalline stalagmitic floor4 ,upon turning to the right1 we come to the ,hall of ,columns1 the most beautiful of all4 ,here the floor bristles with stalagmites1 which in several places are connected with the stalactites that depend from the ceiling4 ,this room is about #ej feet square4 ,after this we reach the ,hall of ,crevices1 #hj feet square1 and this leads to the great ,hall of ,gargas1 which is about #cbh feet in length by #hj1 #ih1 and #aje in width4 ,in certain places enormous fissures in the vault rise to a great height4 ,some of these1 shaped like great inverted funnels1 are more than #fj yards in length4 ,the grotto terminates in the ,creeping ,hall4 ,as its name indicates1 this part of the cave can only be traversed by lying flat upon the belly4 ,it gives access to the upper grotto through a narrow and difficult passage that it would be possible to widen1 and which would then allow visitors to make their exit by traversing the beautiful upper grotto1 whose natural entrance is situated #aej yards above the present one4 ,this latter was blasted out about thirty years ago4 ,upon following the direction of the great crevices1 we reach a small chamber1 wherein are found the ,oubliettes of ,gargas--a vertical well #fe feet feet in depth4 ,the aperture that gives access to this strange well 7rendered important through the paleontological remains collected in it7 is no more than two feet in diameter4 ,such is the general configuration of the grotto4 ,in #ahfe ,dr4 ,garrigou and ,mr4 ,de ,chastaignier visited the grotto1 and were the first to make excavations therein4 ,these latter allowed these scientists to ascertain that the great chamber contained the remains of a quaternary fauna1 and1 near the declivity1 a deposit of the reindeer age4 ,as soon as it was possible to obtain a permit from the ,municipal ,council of ,aventignan to do so1 ,i began the work of excavation1 and the persistence with which ,i continued my explorations led me to discover one of the most important deposits that we possess in the chain of the ,pyrenees4 ,my first excavations in ,bear ,hall were made in #ahgc1 and were particularly fruitful in an opening #bi feet long by #aj wide that terminates the hall1 to the left4 ,i have remarked that these sorts of retreats in grottoes are generally rich in bones4 ,currents of water rushing through the entrance to the grotto carry along the bones--entire1 broken1 or gnawed--that lie upon the ground4 ,these remains are transported to the depths of the cave1 and are often stopped along the walls1 and lie buried in the chambers in argillaceous mud4 ,rounded flint stones are constantly associated with the bones1 and the latter are always in great disorder4 ,the species that ,i met with were as follows3 the great cave bear1 the little bear1 the hyena1 the great cat1 the rhinoceros1 the ox1 the horse1 and the stag4 ,the stalagmitic floor is #a1 #b1 and #b inches thick4 ,the bones were either scattered or accumulated at certain points4 ,they were generally broken1 and often worn and rounded4 ,they appeared to have been rolled with violence by the waters4 ,the clay that contained them was from #c to #f feet in thickness1 and rested upon a stratum of water-worn pebbles whose dimensions varied from the size of the fist to a grain of sand4 ,a thick layer of very hard1 crystalline stalagmite covers the ,hall of ,columns1 and it was very difficult to excavate without destroying this part of the grotto4 ,i found that there anciently existed several apertures that are now sealed up1 either by calcareous concretions or by earthy rubbish from the mountain4 ,one of these was situated in the vicinity of the present mouth1 and permitted of the access to ,bear ,hall of a host of carnivora that found therein a vast and convenient place of shelter4 ,illustration3 ,,fig4 #b4--,,skeleton ,,of ,,the ,,cave ,,hyena4 ,these excavations revealed to me at this entrance1 at the bottom of the declivity1 a thick stratum of remains brought thither by primitive man4 ,this deposit1 which was formed of black earth mixed with charcoal and numerous remains of bones1 calcined and broken longitudinally for the most part1 contained rudely worked flint stones4 ,i collected a few implements1 one surface of which offered a clean fracture1 while the other represented the cutting edge4 ,according to ,mr4 ,de ,mortillet1 such instruments were not intended to have a handle4 ,they were capable of serving as paring knives and saws1 but they were especially designed for scraping bones and skins4 ,the deposit was from #bf to #cb feet square and from #b inches to #e feet deep1 and rested upon a bed of broken stones above the stalagmite4 ,the animals found in it were the modern bear 7rare71 the aurochs1 the ox1 the horse1 and the stag--the last four in abundance4 ,at the extremity of the grotto there is a well with vertical sides which is no less than #fe feet in depth4 ,it is called the ,gargas ,oubilettes4 ,its mouth is from #ae to #bd inches in diameter1 and scarcely gives passage to a man 7,fig4 #a74 ,mr4 ,borderes1 in the hope of discovering a new grotto1 was the first to descend into this well1 which he did by means of a rope ladder1 and collected a few bones that were a revelation to me4 ,despite the great difficulty and danger of excavating at this point1 ,i proceeded1 and found at the first blow of the pick that there was here a deposit of the highest importance1 since all the bones that ,i met with were intact4 ,the first thing collected was an entire skull of the great cave bear1 with its maxillaries in place4 ,from this moment ,i began a series of excavations that lasted two years4 ,the descent is effected through a narrow vertical passage #f feet in length4 ,the cavity afterward imperceptibly widens1 and1 at a depth of #ab yards1 reaches #f feet in diameter1 and at #ae yards #aj feet4 ,finally1 in the widest part 7at a depth of #fb feet7 it measures about #af feet 7,fig4 #a74 ,a glance at the section of the well1 which ,i have drawn as accurately as possible 7not an easy thing to do when one is standing upon a rope ladder71 will give an idea of the form of this strange pocket formed in the limestone of the mountain through the most complex dislocations and erosions4 ,two lateral pockets attracted my attention because of the enormous quantity of clay and bones that obstructed them4 ,the first1 to the left1 was about #ae feet from the orifice4 ,when we had entirely emptied it1 we found that it communicated with the bottom of the well by a narrow passage4 ,an entire skeleton of the great cave bear had stopped up this narrow passage1 and of this1 by the aid of a small ladder1 we gathered the greater part of the skeleton1 the state of preservation of which was remarkable4 ,the second pocket1 which was almost completely filled with clay1 and situated a little lower than the other1 likewise communicated with a third cavity that reached the bottom of the well4 ,the clay of these different pockets contained so large a quantity of bones that we could hardly use our picks1 and the excavation had to be performed with very short hooks1 and often by hand4 ,in this way ,i was enabled to remove the bones without accident4 ,the lower pocket was dug out first1 and with extreme care1 the bones being hoisted out by means of a basket attached to a rope4 ,three or four candles sufficed to give us light4 ,the air was heavy and very warm1 and1 after staying in it for two hours1 it was necessary to come to the surface to breathe4 ,after extracting the bones from the lower pocket1 and when no more clay remained1 we successively dug out the upper ones and threw the earth to the bottom of the well4 ,on the #bjth of ,december1 #ahhd1 my excavating was finished4 ,to-day the ,oubliettes of ,gargas are obstructed with the clay that it was impossible to carry elsewhere4 ,the animals that ,i thus collected in the well were the following3 ,the great bear 7in abundance71 the little bear 7a variety of the preceding71 the hyena1 and the wolf4 ,the pockets contained nearly entire skeletons of these species4 ,how had the animals been able to penetrate this well8 ,it is difficult to admit that it was through the aperture that ,i have mentioned4 ,i endeavored to ascertain whether there was not another communication with the ,gargas grotto1 and had the satisfaction of finding a fissure that ended in the cave1 and that probably was wider at the epoch at which the place served as a lair for the bear and hyena4 ,very old individuals and other adults1 and very young animals1 were living in the grotto1 and1 being surprised1 without power to save themselves1 by a sudden inundation1 reached the bottom of the well that we have described4 ,the entire remains of these animals were carried along by the water and deposited in the pockets in the rock4 ,once buried in the argillaceous mud1 the bones no longer underwent the action of the running water1 and their preservation was thence secured4--,f4 ,regnault1 in ,la ,nature4 99 99 99 99 99 ,,deep ,,shafts ,,and ,,deep ,,mining4 ,a correspondent of the ,new ,york ,sun1 writing from ,virginia ,city1 ,nevada1 describes the progress of the work there on the ,combination shaft of the ,comstock lode1 the deepest vertical shaft in ,america1 and the second deepest in the world4 ,it is being sunk by the ,chollar ,potosi1 ,hale ,norcross1 and ,savage mining companies2 hence its name of the ,combination shaft4 ,this shaft has now reached a perpendicular depth of a little over #c1ajj feet4 ,there is only one deeper vertical shaft in the world--the ,adalbent shaft of the silver-lead mines of ,przibram1 ,bohemia1 which at last accounts had reached a depth of #c1bhj feet4 ,the attainment of that depth was made the occasion of a festival1 which continued three days1 and was still further honored by the striking off of commemorative medals of the value of a florin each4 ,there is no record of the beginning of work on this mine at ,przibram1 although its written history goes back to #aebg4 ,twenty years ago very few mining shafts in the world had reached a depth of #b1jjj feet4 ,the very deepest at that time was in a metalliferous mine in ,hanover1 which had been carried down #b1ijj feet2 but this was probably not a single perpendicular shaft4 ,two vertical shafts near ,gilly1 in ,belgium1 are sunk to the depth of #b1hdg feet4 ,at this point they are connected by a drift1 from which an exploring shaft or winze is sunk to a further depth of #fff feet1 and from that again was put down a bore hole #di feet in depth1 making the total depth reached #c1efb feet4 ,as the bore hole did not reach the seam of coal sought for1 they returned and resumed operations at the #b1hdg level4 ,in ,europe it is thought worthy of particular note that there are vertical shafts of the following depths3 ,feet4 ,eimkert's shaft of the ,luganer ,coal ,mining ,company1 ,saxony #b1fec ,sampson shaft of the ,oberhartz silver mine1 near ,st4 ,andreasberg1 ,hanover4 #b1dcg ,the hoisting shaft of the ,rosebridge ,colliery1 near ,wigan1 ,lancashire1 ,england4 #b1deh ,shaft of the coal mines of ,st4 ,luke1 near ,st4 ,chaumont1 ,france4 #b1bec ,amelia shaft1 ,shemnitz1 ,hungary4 #a1ghb ,the ,no4 #a ,camphausen shaft1 near ,fishbach1 in the department of the ,saarbruck ,collieries1 ,prussia4 #a1fej ,now1 taking the mines of the ,comstock for a distance of over a mile--from the ,utah on the north to the ,alto on the south--there is hardly a mine that is not down over #b1ejj feet1 and most of the shafts are deeper than those mentioned above2 while the ,union ,consolidated shaft has a vertical depth of #b1ijj feet1 and the ,yellow ,jacket a depth of #c1jcj feet4 ,in his closing argument before the ,congressional ,committee on ,mines and ,mining in #ahgb1 ,adolph ,sutro of the ,sutro tunnel said3 ,the deepest hole dug by man since the world has existed is only #b1gjj feet deep1 and it remains for the youngest nation on earth to contribute more to science and geology by giving opportunities of studying the formation of mineral veins at a greater depth than has ever been accomplished by any other nation in the world4 ,mr4 ,sutro was of the opinion that the completion of his tunnel would enable our leading mining companies to reach a vertical depth of #e1jjj feet4 ,this great depth has never yet been attained except in a bore hole or artesian well4 ,the deepest points to which the crust of the earth has ever been penetrated have been by means of such borings in quest of salt1 coal1 or water4 ,a bore hole for salt at ,probst ,jesar1 near ,lubtheen1 for the ,government of ,mecklenberg-,schwerin1 is down #c1cae feet1 the size of which bore is twelve inches at the top and three inches at the bottom4 ,a bore hole was put down for the ,prussian ,government to the depth of #d1ahc feet4 ,but in these bore holes the ,united ,states leads the world1 as there is one near ,st4 ,louis1 ,mo41 that is #e1ejj feet in depth4 ,here on the ,comstock1 in the ,union ,consolidated mine1 a depth of #c1cjj feet has been attained1 but not by means of a single vertical shaft4 ,the vertical depth of the shaft is #b1ijj feet2 the remainder of the depth has been attained by means of winzes sunk from drifts4 ,several long drifts were run at this great depth without difficulty as regards ventilation or heat4 ,the combination shaft is situated much further east 7in which direction the lode dips7 than any other on the ,comstock4 ,it is #c1jjj feet east of the point where the great vein crops out on the side of ,mount ,davidson2 #b1bjj feet east of the old ,chollar-,potosi shaft1 #a1hjj ft4 east of the old ,hale ,norcross 7or ,fair7 shaft1 and #b1jjj ft4 east of the ,savage shaft4 ,thus1 it will be seen it is far out to the front in the country toward which the vein is going4 ,the shaft is sunk in a very hard rock 7andesite71 every foot of which requires to be blasted4 ,the opening is about thirty feet in length by ten feet in width4 ,in timbering up this is divided into four different compartments1 some for the hoisting and some for the pumping machinery1 thus presenting the appearance at the top of four small shafts set in a row4 ,over the shaft stand several large buildings1 all filled with ponderous machinery4 ,the ,sutro drain tunnel 7nearly four miles in length7 connects with the shaft at a depth of #a1fjj ft41 up to which point all the water encountered below is pumped4 ,the shaft was sunk to the depth of #b1bjj ft4 before more water was encountered than could be hoisted out in the skips with the dirt4 ,at the #b1bjj level two ,cornish pumps1 each with columns fifteen inches in diameter1 were put in4 ,at the #b1djj level the same pumps were used4 ,on this level a drift was run that connected with the old ,hale ,norcross and ,savage shafts1 producing a good circulation of air both in the shaft and in the mines mentioned4 ,at this point1 on account of the inflow from the mines consequent upon connecting with them by means of the drift1 they had more water than the ,cornish pumps could handle1 and introduced the hydraulic pumps1 which pumps are run by the pressure of water from the surface through a pipe running down from the top of the shaft1 whereas the ,cornish pumps are run by huge steam engines4 ,by means of the hydraulic pumps they were enabled to sink the shaft to the #b1fjj level1 and extended the ,cornish pumps to that point1 where another set of hydraulic pumps was put in4 ,they then sunk the shaft to the #b1hjj level1 when they ran another drift westward1 and tapped the vein4 ,the prospects at this depth in the ,hale ,norcross and ,chollar mines were so encouraging that the management decided to sink the shaft to the depth of #c1jjj ft4 ,on reaching the #c1jjj level1 they ran a third drift through to the vein4 ,the distance from the shaft to the east wall of the vein was found to be only #bej ft4 ,at the depth of #c1jjj ft4 they put in one of the pair of hydraulic pumps that is to be set up there4 ,the second pump is now arriving from ,san ,francisco1 and as soon as the several parts are on the ground1 it will be at once put in place alongside its fellow on the #c1jjj level4 ,this additional pump will increase the capacity from #fjj1jjj to #gjj1jjj gallons in twenty-four hours1 or about forty-five miners' inches4 ,owing to the excellent showing of ore obtained on the #c1jjj level by the ,hale ,norcross ,company1 and to the continuation of the ore below that level 7as shown by a winze sunk in the vein71 the management determined to sink the shaft to the vertical depth of #c1bjj ft4 ,it is now #c1abj ft4 deep1 and it is safe to say that it will reach the depth of #c1bjj ft4 early in ,september1 when it will lack but eighty feet of being as deep as the shaft at ,przibram was at the time of the great festival4 ,although the shaft is of great size--about thirty feet by ten feet before the timbers are put in--the workmen lower it at the rate of about three feet a day1 in rock as hard as flint4 ,the hydraulic pump now working at the #c1jjj foot level of the shaft is the deepest in the world4 ,in ,europe the deepest is in a mine in the ,hartz ,mountains1 ,germany1 which is working at the depth of #b1gjj feet4 ,it is1 however1 a small pump not half the size of the one in the ,combination shaft4 ,although these pumps were first used in ,europe1 those in operation here are far superior in size1 and in every other respect1 to those of the ,old ,world1 several valuable improvements having been made in them by the machinists of the ,pacific coast4 ,the capacity of the two ,cornish pumps1 which lift the water from the #b1ijj foot level to the ,sutro drain tunnel 7at the #a1fjj level71 is about #a1jjj1jjj gallons in twenty-four hours1 and the capacity of the present hydraulic pumps is #c1ejj1jjj gallons in the same time4 ,they are now daily pumping1 with both hydraulic and ,cornish pumps1 about #d1jjj1jjj gallons1 but could pump at least #ejj1jjj gallons more in twenty-four hours than they are now doing4 ,the daily capacity with the hydraulic pump now coming1 and which will be set up as mate to that now in operation at the #c1jjj foot level1 will be #e1bjj1jjj gallons4 ,the water which feeds the pressure pipe of the three sets of hydraulic pumps is brought from near ,lake ,tahoe1 in the ,sierra ,nevada ,mountains4 ,the distance is about thirty miles1 and the greater part of the way the water flows through iron pipes1 which at one point cross a depression #a1gbj feet in depth4 ,the pressure pipe takes this water from a tank situated on the eastern slope of ,mount ,davidson1 #c1ejj feet west of the shaft4 ,at the tank this pipe is twelve inches in diameter1 but is only eight inches where it enters the top of the shaft4 ,the tank whence the water is taken is #dbf feet higher than the top of the shaft1 therefore the vertical pressure upon the hydraulic pump at the #c1jjj foot level is #c1dbf feet4 ,the pressure pipe is of ordinary galvanized iron where it receives the water at the tank1 but gradually grows thicker and stronger1 and at the #c1jjj level it is constructed of cast iron1 and is #b inches in thickness4 ,the pressure at this point is #a1ejj pounds to the square inch4 ,in the early days of hydraulic mining in ,california the miners thought that with a vertical pressure of #cjj feet they could almost tear the world to pieces1 and not a man among them could have been made to believe that any pipe could be constructed that would withstand a vertical pressure of #a1jjj feet2 but we now see that a thickness of two and a half inches of cast iron will sustain a vertical pressure of over #c1djj feet4 ,there is only one pressure pipe for all the hydraulic pumps4 ,this extends from the tank on the side of the mountain to the #c1jjj foot level4 ,it is tapped at the points where are situated the several sets of hydraulic pumps4 ,the water from the pressure pipe enters one part of the pump1 where it moves a piston-back and forth1 just as the piston of a steam engine is moved by steam4 ,this water engine moves a pump which not only raises to the surface the water which has been used as driving power1 but also a vast quantity of water from the shaft1 all of which is forced up to the ,sutro drain tunnel through what is called a return pipe4 ,each set of hydraulic pumps has its return pipe2 therefore there are three return pipes--one from the #b1djj1 one from the #b1fjj1 and another from the #c1jjj level4 ,some idea may be formed of the great size of these hydraulic engines when it is known that the stations excavated for them at the several levels where they are placed are #he feet long1 #bh feet wide1 and #ab feet high4 ,all this space is so filled with machinery that only sufficient room is left to allow of the workmen moving about it4 ,one of these stations would1 on the surface1 form a hall large enough for a ball room1 and to those who are unacquainted with the skill of our miners it must seem wonderful that such great openings can be made and securely supported far down in the bowels of the earth2 yet it is very effectually done4 ,these great subterranean halls are supported by timbers #adaf inches square set along the walls three feet apart1 from center to center1 and the caps or joists passing overhead are timbers of the same size4 ,the timber used is mountain spruce4 ,not one of these huge stations has thus far cost one dollar for repairs4 ,the station at the #b1djj level has been in use five years1 that at the #b1fjj three years1 and the one at the #c1jjj level eight months4 ,room for ventilation is left behind the timbers1 and all are still sound4 ,timbers of the same kind are used in the shaft1 and all are sound4 ,the shaft has cost nothing for repairs4 ,being in hard andesite rock from top to bottom1 the ground does not swell and crowd upon the timbers4 ,if it shall be thought advisable to go to a greater depth than #c1bjj feet1 a station of large size will be made on the east side of the present shaft1 and in this station will be sunk a shaft of smaller size4 ,the reason why the work will be continued in this way is that in a single hoist of #c1bjj feet the weight of a steel wire cable of that length is very great--so great that the loaded cage it brings up is a mere trifle in comparison4 ,in this secondary shaft the hoisting apparatus and pumps will be run by means of compressed air4 ,as it is very expensive to make compressed air by steam power1 the pressure pipe will be tapped at the level of the ,sutro tunnel1 and a stream of water taken out that will be used in running a turbine wheel of sufficient capacity to drive three air compressors4 ,as there will be a vertical pressure upon the turbine at this depth of over #b1jjj feet1 a large stream of water will not be required4 ,the water used in driving the wheel will flow out through the ,sutro tunnel1 and give no trouble in the shaft4 ,by means of this great shaft and its powerful hydraulic and ,cornish pumps the crust of the earth will probably yet be penetrated to far greater depth than in any other place in the world4 ,it has been only a little over ten years since the work of sinking it was begun1 whereas in the mines of the ,old ,world they have been delving since time whereof the memory of man runneth not to the contrary4 ,the work on the ,combination shaft has been by no means continuous4 ,there have been long stoppages aside from those required at such times as they were engaged in running long drifts to the westward to tap the vein1 and at times for many months1 when the several companies interested in the shaft were engaged in prospecting the various levels it had opened up4 99 99 99 99 99 ,,remarkable ,,wells ,,and ,,caverns4 ,yucatan is one of the most interesting ,states of ,mexico1 owing to the splendid ancient palaces and temples of once grand cities1 now hidden in the forests4 ,that country also presents great attractions for geologists and botanists1 as well as naturalists1 who there find rare and beautiful birds1 insects1 and reptiles4 ,there are no rivers on the surface of the land1 but in many parts it is entirely undermined by extensive caverns1 in which are basins of water fed by subterranean currents4 ,the caverns are delightfully cool even at midday1 and the fantastic forms of some of the stalactites and stalagmites are a never-ending source of interest4 ,there are long winding passages and roomy chambers following one after another for great distances1 with here and there some chink in the stony vault above1 through which a sunbeam penetrates1 enabling us to see to the right and left openings leading to untrodden places in the bowels of the earth4 ,as few of these caves have been explored1 the wildest accounts are given by the natives concerning the dark recesses where only wild beasts seek shelter4 ,before venturing far in1 it is advisable to secure one end of a ball of twine at the entrance1 and keep the ball in hand2 nor is it safe to go without lanterns or torches1 lest we step into some yawning chasm or deep water4 ,the leader of one party suddenly saw a very dark spot just before him2 he jumped over1 instead of stepping on it1 and told the others to halt4 ,examination proved the dark patch to be a pit that seemed bottomless4 ,awe-inspiring as are the interiors of some of these caves1 they are frequently most beautiful4 ,the natural pillars are often grand in dimensions and sparkling with various hues1 while stalactites and stalagmites sometimes resemble familiar objects with astonishing perfection4 ,it is1 however1 not advisable to place implicit confidence in accounts of the natives1 for the reality1 no matter how beautiful1 can hardly be equal to what the vivid imagination of the ,indian has pictured4 ,anything bearing the least resemblance to a woman is called a most beautiful ,virgin ,mary4 ,fantastic flutings become an organ1 and a level rock an altar4 ,only once we were not disappointed1 when1 having been told to look for a pulpit1 we found one that appeared as if man must have fashioned it1 supported on a slender pyramidal base1 the upper part very symmetrical1 and ornamented with a perfect imitation of bunches of grapes and other fruit4 ,as ,i have already said1 in these caves are sheets of water1 some very large1 others only a few feet in circumference1 fed by subterranean currents4 ,when the water is clear and sweet1 it is peopled by a kind of bagre1 a blind fish called by the natives tzau1 also a species of ,silurus4 ,but there are likewise medicinal and thermal waters1 by bathing in which many people claim to have been cured of most painful and obstinate diseases4 ,strange stories are told of some of these waters4 ,of one it is said that those who approach it without holding their breath fall dead4 ,people who live near the place swear it is so1 and say the water appears to boil on such occasions4 ,from the thermal waters1 in some cases #ajj feet below the soil1 and without means of access except by buckets let down through an opening in the rock1 warm vapors issue at early morn1 but when the sun is high the water is cool and pleasant to drink4 ,the name senote is given to all these deposits of water1 also to some immense natural circular wells from #ej to #cjj feet in diameter4 ,the walls are more or less perpendicular1 generally covered with tropical vegetation4 ,the current in some is swift1 but no inlets or outlets are visible4 ,the water is deliciously pure and sweet1 much better than that of wells opened by man in the same country4 ,these enormous deposits generally have a rugged path1 sometimes very steep1 leading to the water's edge1 but daring natives throw themselves from the brink1 afterward ascending by stout roots that hang like ropes down the walls1 the trees above sucking through these roots the life-sustaining fluid more than a hundred feet below4 ,in the west part of ,yucatan is a village called ,bolonchen 7nine wells71 because in the public square there are nine circular openings cut through a stratum of rock4 ,they are mouths of one immense cistern1 if natural or made by hand the natives do not know1 but in times of drought it is empty1 which shows that it is not supplied by any subterranean spring4 ,then the people depend entirely on water found in a cave a mile and a half from the village2 it is perhaps the most remarkable cavern in the whole country4 ,the entrance is magnificently wild and picturesque4 ,it is necessary to carry torches1 for the way is dark and dangerous4 ,after advancing sixty or seventy feet we descend a strong but rough ladder twenty feet long1 placed against a very precipitous rock4 ,not the faintest glimmer of daylight reaches that spot2 but after a while we stand on the brink of a perpendicular precipice1 the bottom of which is strongly illuminated through a hole in the surface rock more than #bjj feet above4 ,standing on the verge of this awful pit in the dim light1 the rocks and crags seem to take on most weird shapes4 ,we go down into the great hole by a ladder eighty feet high and twelve wide1 and1 reaching the bottom1 are as yet but at the mouth of the cave1 which1 by the bye1 is called ,xtacunbi ,xunan 7the hidden lady71 because1 say the ,indians1 a lady was stolen from her mother and hidden there by her lover4 ,now1 to our right1 we find a narrow passage1 and soon another ladder2 the darkness is intense and the descent continuous1 though irregular1 like a series of hills and dales1 ladders being placed against the steepest places4 ,after an exhausting journey we reach a vast chamber1 from which crooked passages lead in various directions to wells1 seven in all1 each named according to the peculiar kind of water4 ,one1 always warm1 is called ,chocoh 7hot water72 another1 ,ocih99 7milky water71 and ,akabh 7dark water74 ,about #djj paces away from the chamber1 passing through a very narrow1 close passage1 there is a basin of red water that ebbs and flows like the sea1 receding with the south wind1 increasing with the northwest4 99,transcriber's note3 c denotes upside-down 'c' in original4 ,to reach the most distant well1 we go down yet one more ladder1 the seventh4 ,on one side of it there is a perpendicular wall1 on the other a yawning gulf1 so when one of the steps1 merely round sticks tied with withes1 gave way beneath our feet1 we tightly grasped the stick above4 ,having reached the bottom of the ladder1 we crawl on our hands and feet through a broken1 winding passage about #hjj feet long1 then see before us a basin of crystalline water1 and how thirsty we are6 ,this basin is #a1djj feet from the mouth of the cave1 and about #dej feet below the earth's surface4 ,several hundred people during five months in every year depend entirely on that source for all the water they use4 ,with their frail pitchers and flaring torches they wend their way1 gasping for breath1 through the intricate passages1 and reaching the water1 are so profusely perspiring that they must wait before quenching their thirst4 ,the way back is even harder1 and they are tired and loaded2 yet these people are such lovers of cleanliness that on their arrival at their poor huts1 before tasting food1 they will use some of the water that has cost them so much1 to bathe their smoke-begrimed skin4 ,as several women once fainted in the cave1 men generally fetch the water now4 ,yucatan is1 and has been for ages past1 quite free from earthquakes1 while all surrounding countries are from time to time convulsed4 ,this immunity may be due to the vast caverns and numerous great wells existing throughout the land4 ,pliny the ,elder was of opinion that if numerous deep wells were made in the earth to serve as outlets for the gases that disturb its upper strata1 the strength of the earthquakes would be diminished1 and if we may judge by ,yucatan1 ,pliny was right in his conjectures4 ,after him1 other scientists who have carefully studied the subject have expressed the same opinion with regard to the efficacy of large wells4 ,,alice ,d4 ,,le ,,plongeon4 ,brooklyn1 ,july #ae1 #ahhe4 99 99 99 99 99 ,cholera failed to strike a single one of the #d1jjj women employed in the national tobacco factory at ,valencia1 ,spain1 though the disease raged violently in that city1 and the ,medical ,world recalls that tobacco workers were also noticed to enjoy exemption from attack during an epidemic at ,amsterdam4 99 99 99 99 99 ,,the ,,cabbage ,,butterfly4 ,a patch of eggs and the minute caterpillars or larv nearly emerged from them are seen on the leaf4 ,these tiny eggs are at first quite white or pale yellow1 and form an object for the microscope of remarkable beauty1 which is worthy of the examination of all who take an interest in the garden and its insect life4 ,an egg magnified is drawn at the bottom left-hand corner of the woodcut4 ,when the eggs are near the hatching point they darken in color1 and a magnifying glass reveals through the delicate transparent shell a sight which fills the observer with amazement2 the embryo caterpillar is seen in gradual course of formation1 and if patience and warmth have permitted it1 the observer will witness slight movements within the life-case1 and presently the shell will break and a black head with moving jaws will be thrust out2 the little caterpillar unfolds and slowly crawls away from the egg-shell1 and inserts its jaws into the green leaf4 ,it is curious to witness how judiciously the little creatures avoid crowding together1 but strike out in different directions1 and thus they make sure of a plentiful supply of food1 and distribute the effects of their depredations4 ,these caterpillars eat continually1 and hence rapidly increase in size1 until they present the appearance shown in our drawing at the bottom of the illustration1 which is a full grown caterpillar4 ,illustration3 ,,the ,,cabbage ,,and ,,peacock ,,butterflies4 ,it will be observed that this insect is composed of thirteen segments from head to tail1 which is a distinctive characteristic of all insects both in the larval and perfect states2 but in the case of this and most other caterpillars these segments are sharply defined and readily recognized4 ,it will also be noticed that the three segments or joints nearest the head bear a pair of legs each2 these are the real feet1 or claspers1 as they are sometimes termed1 which develop into the feet of the future butterfly4 ,there are four pairs of false feet or suckers1 which adhere to the ground by suction1 and which disappear in the butterfly4 ,on the last or tail end is a fifth pair of suckers also1 which can attach themselves to a surface with considerable force1 as any one can attest who has noticed the wrigglings of one of these caterpillars when feeling for new feeding ground4 ,the caterpillar now ceases to eat1 and quietly betakes itself to a secluded corner1 where in peace it spins a web around its body1 and wrapt therein remains quiescent1 awaiting its change into the butterfly4 ,although so dormant outwardly1 activity reigns inside2 processes are going on within that chrysalis-case which are the amazement and the puzzle of all naturalists4 ,in course of time the worm is changed into the beautiful winged butterfly1 which breaks its case and emerges soft and wet2 but it quickly dries and spreads its wings to commence its life in the air and sunshine4 ,the chrysalis is represented in the figure on the left4 ,the butterfly1 it will be recognized1 is one of the common insects so familiar to all1 with strongly veined white wings1 bearing three black spots1 two on the upper and one on the lower wing1 and dark coloring on the corner of the upper wings4 ,the antenn1 as with all butterflies1 are clubbed at the extremity--unlike moths'1 which are tapering--and the large black staring eyes are the optical apparatus1 containing1 we are told1 thousands of lenses1 each a perfect1 simple eye4 ,the wings derive their chief coloring from the covering of scales1 which lie on like slates on a roof1 and are attached in a similar manner4 ,a small portion of the wing magnified is represented at the bottom right hand corner1 and detached scales more highly magnified next to it1 exhibiting somewhat the form of battledoors4 ,,the ,,peacock ,,butterfly4 ,another well known insect is illustrated in the figure in the upper portion--the peacock butterfly 7,vanessa ,io74 ,the curious spiked and spotted caterpillar feeds upon the common nettle4 ,this beautiful butterfly--common in most districts--is brilliantly colored and figured on the upper side of the wings1 but only of a mottled brown on the under surface1 somewhat resembling a dried and brown leaf1 so that it is no easy matter to detect the conspicuous1 brightly-decked insect when it alights from flight upon foliage1 and brings its wings together over its back after the manner of butterflies4 ,at the left-hand corner is seen the head of the insect1 magnified1 showing the long spiral tongue4 ,this is a curious structure1 and one that will repay the trouble of microscopic examination4 ,in the figure the profile is seen1 the large compound eye at the side and the long curved tongue1 so elephantine-looking in form1 though of minute size1 is seen unrolled as it is when about to be inserted into flowers to pump up the honey-juice4 ,this little piece of insect apparatus is a mass of muscles and sensitive nerves comprising a machine of greater complexity and of no less precision in its action than the modern printing machine4 ,when not in use1 the tongue rolls into a spiral and disappears under the head4 ,a butterfly's tongue may readily be unrolled by carefully inserting a pin within the first spiral and gently drawing it out4--,the ,gardeners' ,chronicle4 99 99 99 99 99 ,,the ,,bhotan ,,cypress4 7,,cupressus ,,torulosa47 ,this cypress1 apart from its elegant growth1 is interesting as being the only species of ,cupressus indigenous to ,india4 ,it is a native of the ,himalayas in the ,bhotan district1 and it also occurs on the borders of ,chinese ,tartary4 ,it forms1 therefore1 a connecting link1 as it were1 between the true cypresses of the extreme east and those that are natives of ,europe4 ,it is singular to note that this genus of conifers extends throughout the entire breadth of the northern hemisphere1 ,cupressus funebris representing the extreme east in ,china1 and ,c4 macrocarpa the extreme west on the ,californian seacoast4 ,the northerly and southerly limits1 it is interesting to mark1 are1 on the contrary1 singularly restricted1 the most southerly being found in ,mexico2 the most northerly 7,c4 nutkaensis7 in ,nootka ,sound1 and the subject of these remarks 7,c4 torulosa7 in ,bhotan4 ,the whole of the regions intervening between these extreme lateral points have their cypresses4 ,the ,european species are ,c4 lusitanica 7the cedar of ,goa71 which inhabits ,spain and ,portugal2 ,c4 sempervirens 7the ,roman cypress71 which is centered chiefly in the southeasterly parts of ,europe1 extending into ,asia ,minor4 ,farther eastward ,c4 torulosa is met with1 and the chain is extended eastward by ,c4 funebris1 also known as ,c4 pendula4 ,the headquarters of the cypresses are undoubtedly in the extreme west1 for here may be found some four or five distinct species1 including the well-known ,c4 ,lawsoniana1 probably the most popular of all conifer in gardens1 ,c4 ,goveniana1 ,c4 ,macnabiana1 ,c4 macrocarpa1 and ,c4 nutkaensis 7spelt ,c4 nutkanus by the ,californian botanists74 ,the eastern representative of the cypresses in the ,united ,states of ,north ,america is ,c4 thyoides1 popularly known as the white cedar4 ,in ,mexico three or four species occur1 so that the genus in round numbers only contains about a dozen species4 ,the ,californian botanist ,mr4 ,sereno ,watson takes away ,lawson's cypress from ,cupressus and puts it in the genus ,chamcyparis1 the chief points of distinction being the flattened two-ranked branchlets and the small globose cones maturing the first year4 ,illustration3 ,,cones ,,of ,,cupressus ,,torulosa 7,,natural ,,size74 ,all the cypresses are undoubtedly valuable from a garden point of view1 but the various species vary in degree as regards their utility as ornamental subjects4 ,i should rank them in the following order in point of merit3 ,c4 ,lawsoniana1 ,c4 nutkaensis1 ,c4 macrocarpa1 ,c4 sempervirens1 ,c4 thyoides1 ,c4 ,macnabiana1 and ,c4 ,goveniana2 then would follow ,c4 torulosa1 ,c4 funebris1 ,c4 ,knightiana1 and other ,mexican species4 ,these are placed last1 not because they are less elegant than the others1 but on account of their tenderness1 all being liable to succumb to our damp and cold winters4 ,the species which concerns us at present1 ,c4 torulosa1 is an old introduction1 seeds of it having been sent to this country by ,wallich so long back as #ahbd1 and previous to this date it was found by ,royle on the ,himalayas1 growing at elevations of some #aa1ejj feet above sea level4 ,coming from such a height1 one would suppose it to be hardier than it really is1 but its tenderness may probably be accounted for by the wood not getting thoroughly ripened during our summers4 ,it is a very handsome tree1 said to reach from #bj feet to #abe feet in height in its native habitat4 ,it has a perfectly straight stem2 the growth is pyramidal or rather conical1 and the old wood is of a warm purplish-brown4 ,the foliage is a glaucous gray-green1 and the branches have a twisted and tufted appearance4 ,there are several varieties of it which are1 or have been1 in cultivation4 ,of these one of the best is corneyana1 which ,gordon ranked as a distinct species4 ,it was supposed to be ,chinese1 and was introduced to cultivation by ,messrs4 ,knight ,perry1 the predecessors of ,messrs4 ,veitch at the ,chelsea ,nurseries4 ,it differs from ,c4 torulosa proper1 its habit being of low stature1 and has slender pendulous branches2 hence1 it has been known in gardens by the names of ,c4 gracilis1 ,c4 cernua1 and ,c4 pendula4 ,other varieties of ,c4 torulosa are those named in gardens and nurseries--viridis1 a kind devoid of the glaucous foliage of the original2 majestica1 a robust variety2 and nana1 a very dwarf and compact-growing sort4 ,there is also a so-called variegated form1 but it is not worthy of mention4 ,the synonyms of ,c4 torulosa itself are ,c4 cashmeriana1 ,c4 nepalensis1 and ,c4 pendula4 ,having regard to the tenderness of this ,bhotan cypress1 it should only be planted in the warmest localities1 and in dry sheltered positions2 upland districts1 too1 provided they are sheltered1 are undoubtedly suitable for it1 inasmuch as growth is retarded in spring1 and1 therefore1 the young shoots escape injury from late spring frosts4--,w4,g41 in ,the ,garden4 99 99 99 99 99 ,,the ,,pitcher ,,plant4 ,the variety of the pitcher plant 7,sarracenia variolaris7 found in ,north ,america is carnivorous1 being a feeder on various animal substances4 ,mrs4 ,mary ,treat1 an ,american naturalist1 made1 a few years ago1 several experiments upon the plants of this species to be found in ,florida2 and to the labors of this lady the writer has been indebted1 in some measure1 in the preparation of this paper4 ,the ,sarracenia derives its name of pitcher plant from the fact of its possessing the following curious characteristics3 ,the median nerve is prolonged beyond the leaves in the manner of a tendril1 and terminates in a species of cup or urn4 ,this cup is ordinarily three or four inches in depth1 and one to one and a half inches in width4 ,the orifice of the cup is covered with a lid1 which opens and shuts at certain periods4 ,at sunrise the cup is found filled with sweet1 limpid water1 at which time the lid is down4 ,in the course of the day the lid opens1 when nearly half the water is evaporated2 but during the night this loss is made up1 and the next morning the cup is again quite full1 and the lid is shut4 ,about the middle of ,march the plants put forth their leaves1 which are from six to twelve inches long1 hollow1 and shaped something like a trumpet1 while the aperture of the apex is formed almost precisely in the same manner as those of the plants previously described4 ,a broad wing extends along one side of the leaf1 from the base to the opening at the top2 this wing is bound or edged with a purple cord1 which extends likewise around the cup4 ,this cord secretes a sweet fluid1 and not only flying insects1 but those also that crawl upon the ground1 are attracted by it to the plants4 ,ants1 especially1 are very fond of this fluid1 so that a line of aphides1 extending from the base to the summit of a leaf1 may frequently be observed slowly advancing toward the orifice of the cup1 down which they disappear1 never to return4 ,flying insects of every kind are equally drawn to the plant2 and directly they taste the fluid1 they act very curiously4 ,after feeding upon the secretions for two or three minutes they become quite stupid1 unsteady on their feet1 and while trying to pass their legs over their wings to clear them1 they fall down4 ,it is of no use to liberate any of the smaller insects2 every fly1 removed from the leaf upon which it had been feeding1 returned immediately it was at liberty to do so1 and walked down the fatal cup as though drawn to it by a species of irresistible fascination4 ,it is not alone that flies and other small insects are overpowered by the fluid which exudes from the cord in question4 ,even large insects succumb to it1 although of course not so quickly4 ,mrs4 ,treat says3 ,a large cockroach was feeding on the secretion of a fresh leaf1 which had caught but little or no prey4 ,after feeding a short time the insect went down the tube so tight that ,i could not dislodge it1 even when turning the leaf upside down and knocking it quite hard4 ,it was late in the evening when ,i observed it enter2 the next morning ,i cut the tube open2 the cockroach was still alive1 but it was covered with a secretion produced from the inner surface of the tube1 and its legs fell off as ,i extricated it4 ,from all appearance the terrible ,sarracenia was eating its victim alive4 ,and yet1 perhaps1 ,i should not say 'terrible1' for the plant seems to supply its victims with a ,lethe-like draught before devouring them4 ,if only a few insects alight upon a leaf1 no unpleasant smell is perceptible during or after the process of digestion2 but if a large number of them be caught1 which is commonly the case1 a most offensive odor emanates from the cup1 although the putrid matter does not appear to injure in any manner the inner surface of the tube1 food1 even in this condition1 being readily absorbed1 and going to nourish the plant4 ,in fact1 it would seem that the ,sarracenia1 like some animals1 can feed upon carrion and thrive upon it4 ,in instances in which experiments have been made with fresh1 raw beef or mutton1 the meat has been covered in a few hours with the secretions of the leaves1 and the blood extracted from it4 ,there is1 however1 one difference between the digesting powers of the leaves when exercised upon insects or upon meat4 ,even if the bodies of insects have become putrid1 the plant1 as has already been stated1 has no difficulty in assimilating them2 but as regards meat1 it is only when it is perfectly sweet that the secretions of the leaves will act upon it4 ,the pitcher plant undoubtedly derives its principal nourishment from the insects it eats4 ,it1 too--unlike most other carnivorous plants1 which1 when the quantity of food with which they have to deal is in excess of their powers of digestion1 succumb to the effort and die--appears to find it easy to devour any number of insects1 small or large1 the operation being with it simply a question of time4 ,flies1 beetles1 or even cockroaches1 at the expiration of three or four days at most1 disappear1 nothing being left of them save their wings and other hard1 parts of their bodies4 ,the ,sarracenia is1 indeed1 not only the most voracious of all known species of carnivorous plants1 but the least fastidious as to the nature of the food upon which it feeds4--,w4,c4,m41 ,nature4 99 99 99 99 99 ,,what ,,is ,a ,,plant8 ,mr4 ,worsley-,benison has been discussing this question in a very interesting way1 and he says in conclusion that physiologically the most distinctive feature of plant-life is the power to manufacture protein from less complex bodies2 that of animal-life1 the absence of such power4 ,he finds that in form1 in the presence of starch1 of chlorophyl1 in power of locomotion1 in the presence of circulatory organs1 of the body called nitrogen1 in the functions of respiration and sensation1 there are no diagnostic characters4 ,he finds1 however1 fairly constant and well-marked distinctions in the presence of a cellulose coat in the plant-cell1 in digestion followed by absorption1 and in the power to manufacture protein4 ,the morphological feature of plants is this cellulose coat2 of animals1 its absence2 the physiological peculiarity of plants1 this manufacturing power2 of animals1 the want of it4 ,but after all the discussion he says3 ,to the question1 ,is this an animal or a plant8 we must often reply1 ,we do not know4--,the ,microscope4 99 99 99 99 99 ,,camellias4 ,next to the rose1 no flower99 is more beautiful or more useful than the camellia4 ,it may readily be so managed that its natural season of blooming shall be from ,october to ,march1 thus coming in at a time when roses can hardly be had without forcing4 ,in every quality1 with the single exception of scent1 the camellia may be pronounced the equal of the rose4 ,it can be used in all combinations or for all purposes for which roses can be employed4 ,in form and color it is probably more perfect1 and fully as brilliant4 ,it is equally or more durable1 either on the plant or as a cut flower4 ,it is a little dearer to buy1 and perhaps slightly more difficult to cultivate2 but like most plants the camellia has crucial periods in its life1 when it needs special treatment4 ,that given1 it may be grown with the utmost ease2 that withheld1 its culture becomes precarious1 or a failure4 ,the camellia is so hardy that it will live in the open air in many parts of ,great ,britain1 and herein lies a danger to many cultivators4 ,because it is quite or almost hardy1 they keep it almost cool4 ,this is all very well if the cool treatment be not carried to extremes1 and persisted in all the year round4 ,camellias in a dormant state will live and thrive in any temperature above the freezing point1 and will take little or no hurt if subjected to from #c-d below it1 or a temperature of #bg ,fahr4 99 ,transcriber's ,note3 ,original flour4 ,they will also bloom freely in a temperature of #dj1 though #de suits them better4 ,hence1 during the late summer and early autumn it is hardly possible to keep camellias too cool either out of doors or in4 ,they are also particularly sensitive to heat just before the flower-buds begin to swell in late autumn or winter2 a sudden or sensible rise of temperature at that stage sends the flower-buds off in showers4 ,this is what too often happens1 in fact1 to the camellias of amateurs4 ,no sooner do the buds begin to show then a natural impatience seizes the possessor's of well-budded camellias to have the flowers opened4 ,more warmth1 a closer atmosphere1 is brought to bear upon them1 and down fall the buds in showers on stage or floor--the chief cause of this slip between the buds and the open flowers being a rise of temperature4 ,a close or arid atmosphere often leads to the same results4 ,camellias can hardly have too free a circulation of air or too low a temperature4 ,another frequent cause of buds dropping arises from either too little or too much water at the roots4 ,either a paucity or excess of water at the roots should lead to identical results4 ,most amateurs overwater their camellias during their flowering stages4 ,seeing so many buds expanding1 they naturally rush to the conclusion that a good deal of water must be used to fill them to bursting point4 ,but the opening of camellia buds is less a manufacture than a mere development1 and the strain on the plant and drain on the roots is far less during this stage than many suppose4 ,of course the opposite extreme of over-dry roots must be provided against1 else this would also cause the plants to cast off their buds4 ,but our object now is less to point out how buds are to be developed into fully expanded flowers than to show how they were to be formed in plenty1 and the plants preserved in robust health year after year4 ,one of the simplest and surest modes of reaching this desirable end is to adopt a system of semi-tropical treatment for two months or so after flowering4 ,the moment or even before the late blooms fade1 the plants should be pruned if necessary4 ,few plants bear the knife better than camellias1 though it is folly to cut them unless they are too tall or too large for their quarters or have grown out of form4 ,as a rule healthy camellias produce sufficient or even a redundancy of shoots without cutting back2 but should they need pruning1 after flowering is the best time to perform the operation4 ,during the breaking of the tender leaves and the growth of the young shoots in their first stages1 the plant should be shaded from direct sunshine1 unless1 indeed1 they are a long way from the glass1 when the diffusion and dispersion of the rays of light tone down or break their scorching force2 few young leaves and shoots are more tender and easily burned than camellia1 and scorching not only disfigures the plants1 but also hinders the formation of fine growths and the development of flower-buds4 ,the atmosphere during the early season of growth may almost touch saturation4 ,it must not fail to be genial1 and this geniality of the air must be kept up by the surface-sprinkling of paths1 floors1 stages1 walls1 and the plants themselves at least twice a day4 ,with the pots or border well drained it is hardly possible to overwater the roots of camellias during their period of wood-making4 ,the temperature may range from #ej to #fe during most of the period4 ,as the flower-buds form1 and become more conspicuous1 the tropical treatment may become less and less tropical1 until the camellias are subjected to the common treatment of greenhouse or conservatory plants in summer4 ,even at this early stage it is wise to attend to the thinning of the buds4 ,many varieties of camellias--notably that most useful of all varieties1 the double white--will often set and swell five or ten times more buds than it ought to be allowed to carry4 ,nothing is gained1 but a good deal is lost1 by allowing so many embryo flower-buds to be formed or partially developed4 ,it is in fact far wiser to take off the majority of the excess at the earliest possible point1 so as to concentrate the strength of the plant into those that remain4 ,as it is1 however1 often a point of great moment to have a succession of camellia flowers for as long a period as possible on the same plants1 buds of all sizes should be selected to remain4 ,fortunately1 it is found in practice that the plants1 unless overweighted with blooms1 do not cast off the smaller or later buds in their efforts to open their earlier and larger ones4 ,with the setting1 thinning1 and partial swelling of the flower-buds the semi-tropical treatment of camellias must close2 continued longer1 the result would be their blooming out of season1 or more probably their not blooming at all4 ,the best place for camellias from the time of setting their flower-buds to their blooming season is a vexed question1 which can hardly be said to have been settled as yet4 ,they may either be left in a cool greenhouse1 or placed in a shaded1 sheltered position in the open air4 ,some of the finest camellias ever seen have been placed in the open air from ,june to ,october4 ,these in some cases have been stood behind south1 and in others behind west walls4 ,those facing the east in their summer quarters were1 on the whole1 the finest1 many of them being truly magnificent plants1 not a few of them having been imported direct from ,florence at a time when camellias were far less grown in ,england than now4 ,in all cases where camellias are placed in the open air in summer1 care will be taken to place the pots on worm proof bases1 and to shield the tops from direct sunshine from #aj to #d o'clock4 ,if these two points are attended to1 and also shelter from high winds1 it matters little where they stand4 ,in all cases it is well to place camellias under glass shelter early in ,october1 less for fear of cold than of saturating rains causing a sodden state of the soil in the pots4 ,while adverting1 however1 to the safety and usefulness of placing camellias in the open air in summer1 it must not be inferred that this is essential to the successful culture2 it is1 in fact1 far otherwise1 as the majority of the finest camellias in the country are planted out in conservatories with immovable roofs4 ,many such houses are1 however1 treated to special semi-tropical treatment as has been described1 and are kept as cool and open as possible after the flower-buds are fairly set1 so that the cultural and climatic conditions approximate as closely as possible to those here indicated4 ,soil and seasons of potting may be described as vexed questions in camellia culture4 ,as to the first1 some affect pure loam1 others peat only1 yet more a half and half of both1 with a liberal proportion of gritty sand1 or a little smashed charcoal or bruised bones as porous or feeding agents1 or both4 ,most growers prefer the mixture1 and as good camellias are grown in each of its constituents1 it follows without saying that they may also be well grown in various proportions of both4 ,under rather than over potting suits the plants best1 and the best time is doubtless just before they are about to start into fresh growth1 though many good cultivators elect to shift their plants in the late summer or autumn1 that is1 soon after the growth is finishing1 and the flower-buds fairly and fully set for the next season4 ,from all which it is obvious that the camellia is not only among the most useful and showy1 but likewise among the most accommodating of plants4 ,under good cultivation it is also one of the cleanest1 though when scab gets on it1 it is difficult to get rid of it4 ,mealy-bugs also occasionally make a hurried visit to camellias when making their growth1 as well as aphides4 ,but the leaves once formed and advanced to semi-maturity are too hard and leathery for such insects1 while they will bear scale being rubbed off them with impunity4 ,but really well-grown camellias1 as a rule1 are wholly free from insect pests1 and their clean1 dark1 glossy leaves are only of secondary beauty to their brilliant1 exquisitely formed1 and many sized flowers4--,d4,t41 ,the ,gardeners' ,chronicle4 99 99 99 99 99 ,,aris,,ma ,,fimbriatum4 ,mast42 sp4 nov4 ,illustration3 ,,aris,,ma ,,fimbriatum3 ,,leaf1 ,,spathe1 ,,and ,,floral ,,details4 ,some few years since we had occasion to figure some very remarkable ,himalayan species of this genus1 in which the end of the spadix was prolonged into a very long1 thread-like appendage thrown over the leaves of the plant or of its neighbors1 and ultimately reaching the ground1 and thus1 it is presumed1 affording ants and other insects means of access to the flowers1 and consequent fertilization4 ,these species were grown by ,mr4 ,elwes1 and exhibited by him before the ,scientific ,committee4 ,the present species is of somewhat similar character1 but is1 we believe1 new alike to gardens and to science4 ,we met with it in the course of the autumn in the nursery of ,messrs4 ,sander1 at ,st4 ,alban's2 but learn that it has since passed into the hands of ,mr4 ,w4 ,bull1 of ,chelsea4 ,it was imported accidentally with orchids1 probably from the ,philippine ,islands4 ,it belongs to ,engler's section1 trisecta1 having two stalked leaves1 each deeply divided into three ovate acute glabrous segments4 ,the petioles are long1 pale purplish1 rose-colored1 sprinkled with small purplish spots4 ,the spathes are oblong acute or acuminate1 convolute at the base1 brownish-purple1 striped longitudinally with narrow whitish bands4 ,the spadix is cylindrical1 slender1 terminating in along1 whip-like extremity1 much longer than the spathe4 ,the flowers have the arrangement and structure common to the genus1 the females being crowded at the base of the spadix1 the males immediately above them1 and these passing gradually into fleshy incurved processes1 which in their turn pass gradually into long1 slender1 purplish threads1 covering the whole of the free end of the spadix4--,m4,t4,m41 in ,the ,gardeness' ,chronicle4 99 99 99 99 99 ,,striking ,a ,,light4 ,in the new edition of ,mason's ,burma we read that among other uses to which the bamboo is applied1 not the least useful is that of producing fire by friction4 ,for this purpose a joint of thoroughly dry bamboo is selected1 about #a inches in diameter1 and this joint is then split in halves4 ,a ball is now prepared by scraping off shavings from a perfectly dry bamboo1 and this ball being placed on some firm support1 as a fallen log or piece of rock1 one of the above halves is held by its ends firmly down on it1 so that the ball of soft fiber is pressed with some force against its inner or concave surface4 ,another man now takes a piece of bamboo a foot long or less1 and shaped with a blunt edge1 something like a paper knife1 and commences a sawing motion backward and forward across the horizontal piece of bamboo1 and just over the spot where the ball of soft fiber is held4 ,the motion is slow at first1 and by degrees a groove is formed1 which soon deepens as the motion increases in quickness4 ,soon smoke arises1 and the motion is now made as rapid as possible1 and by the time the bamboo is cut through not only smoke but sparks are seen1 which soon ignite the materials of which the ball beneath is composed4 ,the first tender spark is now carefully blown1 and when well alight the ball is withdrawn1 and leaves and other inflammable materials heaped over it1 and a fire secured4 ,this is the only method that ,i am aware of for procuring fire by friction in ,burma1 but on the hills and out of the way parts1 that philosophical toy1 the pyrophorus1 is still in use4 ,this consists#a of a short joint of a thick woody bamboo1 neatly cut1 which forms a cylinder4 ,at the bottom of this a bit of tinder is placed1 and a tightly-fitting piston inserted composed of some hard wood4 ,the tube being now held in one hand1 or firmly supported1 the piston is driven violently down on the tinder by a smart blow from the hand1 with the result of igniting the tinder beneath4 ,footnote #a3 ,it is also made of a solid cylinder of buffalo's horn1 with a central hollow of three-sixteenths of an inch in diameter and three inches deep burnt into it4 ,the piston1 which fits very tightly in it1 is made of iron-wood or some wood equally hard4 ,another method of obtaining fire by friction from bamboos is thus described by ,captain ,t4,h4 ,lewin 7,hill ,tracts of ,chittagong1 and the ,dwellers ,therein1 ,calcutta1 #ahfi1 p4 #hc71 as practiced in the ,chittagong ,hills4 ,the ,tipporahs make use of an ingenious device to obtain fire2 they take a piece of dry bamboo1 about a foot long1 split it in half1 and on its outer round surface cut a nick1 or notch1 about an eighth of an inch broad1 circling round the semi-circumference of the bamboo1 shallow toward the edges1 but deepening in the center until a minute slit of about a line in breadth pierces the inner surface of the bamboo fire-stick4 ,then a flexible strip of bamboo is taken1 about #a feet long and an eighth of an inch in breadth1 to fit the circling notch1 or groove1 in the fire-stick4 ,this slip or band is rubbed with fine dry sand1 and then passed round the fire-stick1 on which the operator stands1 a foot on either end4 ,then the slip1 grasped firmly1 an end in each hand1 is pulled steadily back and forth1 increasing gradually in pressure and velocity as the smoke comes4 ,by the time the fire-band snaps with the friction there ought to appear through the slit in the fire-stick some incandescent dust1 and this placed1 smouldering as it is1 in a nest of dry bamboo shavings1 can be gently blown into a flame4--,the ,gardeners' ,chronicle4 99 99 99 99 99 ,,experiments ,,in ,,memory4 ,when we read how one medival saint stood erect in his cell for a week without sleep or food1 merely chewing a plantain-leaf out of humility1 so as not to be too perfect2 how another remained all night up to his neck in a pond that was freezing over2 and how others still performed for the glory of ,god feats no less tasking to their energies1 we are inclined to think1 that1 with the gods of yore1 the men1 too1 have departed1 and that the earth is handed over to a race whose will has become as feeble as its faith4 ,but we ought not to yield to these instigations1 by which the evil one tempts us to disparage our own generation4 ,the gods have somewhat changed their shape1 'tis true1 and the men their minds2 but both are still alive and vigorous as ever for an eye that can look under superficial disguises4 ,the human energy no longer freezes itself in fish-ponds1 and starves itself in cells2 but near the north pole1 in central ,africa1 on ,alpine couloirs1 and especially in what are nowadays called psycho-physical laboratories1 it maybe found as invincible as ever1 and ready for every fresh demand4 ,to most people a north pole expedition would be an easy task compared with those ineffably tedious measurements of simple mental processes of which ,ernst ,heinrich ,weber set the fashion some forty years ago1 and the necessity of extending which in every possible direction becomes more and more apparent to students of the mind4 ,think of making forty thousand estimates of which is the heavier of two weights1 or seventy thousand answers as to whether your skin is touched at two points or at one1 and then tabulating and mathematically discussing your results6 ,insight is to be gained at no less price than this4 ,the new sort of study of the mind bears the same relation to the older psychology that the microscopic anatomy of the body does to the anatomy of its visible form1 and the one will undoubtedly be as fruitful and as indispensable as the other4 ,dr4 ,ebbinghaus#a makes an original addition to heroic psychological literature in the little work whose title we have given4 ,for more than two years he has apparently spent a considerable time each day in committing to memory sets of meaningless syllables1 and trying to trace numerically the laws according to which they were retained or forgotten4 ,most of his results1 we are sorry to say1 add nothing to our gross experience of the matter4 ,here1 as in the case of the saints1 heroism seems to be its own reward4 ,but the incidental results are usually the most pregnant in this department2 and two of those which ,dr4 ,ebbinghaus has reached seems to us to amply justify his pains4 ,the first is1 that1 in forgetting such things as these lists of syllables1 the loss goes on very much more rapidly at first than later on4 ,he measured the loss by the number of seconds required to relearn the list after it had been once learned4 ,roughly speaking1 if it took a thousand seconds to learn the list1 and five hundred to relearn it1 the loss between the two learnings would have been one-half4 ,measured in this way1 full half of the forgetting seems to occur within the first half-hour1 while only four-fifths is forgotten at the end of a month4 ,the nature of this result might have been anticipated1 but hardly its numerical proportions4 ,footnote #a3 ,ueber das ,gedchtniss4 ,untersuchungen zur experimentellen ,psychologie4 ,von ,herm4 ,ebbinghaus4 ,leipzig3 ,duncker u4 ,humblot1 #ahhe4 #ajafi pp4 #hvo4 ,the other important result relates to the question whether ideas are recalled only by those that previously came immediately before them1 or whether an idea can possibly recall another idea1 with which it was never in immediate contact1 without passing through the intermediate mental links4 ,the question is of theoretic importance with regard to the way in which the process of association of ideas must be conceived2 and ,dr4 ,ebbinghaus' attempt is as successful as it is original1 in bringing two views1 which seem at first sight inaccessible to proof1 to a direct practical test1 and giving the victory to one of them4 ,his experiments conclusively show that an idea is not only associated directly with the one that follows it1 and with the rest through that1 but that it is directly associated with all that are near it1 though in unequal degrees4 ,he first measured the time needed to impress on the memory certain lists of syllables1 and then the time needed to impress lists of the same syllables with gaps between them4 ,thus1 representing the syllables by numbers1 if the first list was #a1 #b1 #c1 #d 444 #ac1 #ad1 #ae1 #af1 the second would be #a1 #c1 #e 444 #ae1 #b1 #d1 #f 444 #af1 and so forth1 with many variations4 ,now1 if #a and #c in the first list were learned in that order merely by #a calling up #b1 and by #b calling up #c1 leaving out the #b ought to leave #a and #c with no tie in the mind2 and the second list ought to take as much time in the learning as if the first list had never been heard of4 ,if1 on the other hand1 #a has a direct influence on #c as well as on #b1 that influence should be exerted even when #b is dropped out2 and a person familiar with the first list ought to learn the second one more rapidly than otherwise he could4 ,this latter case is what actually occurs2 and ,dr4 ,ebbinghaus has found that syllables originally separated by as many as seven intermediaries still reveal1 by the increased rapidity with which they are learned in order1 the strength of the tie that the original learning established between them1 over the heads1 so to speak1 of all the rest4 ,it may be that this particular series of experiments is the entering wedge of a new method of incalculable reach in such questions4 ,the future alone can show4 ,meanwhile1 when we add to ,dr4 ,ebbinghaus' heroism in the pursuit of true averages1 his high critical acumen1 his modest tone1 and his polished style1 it will be seen that we have a new-comer in psychology from whom the best may be expected4--,w4,j41 ,science4 99 99 99 99 99 ,,sinking ,,of ,,the ,,quievrechain ,,working ,,shaft4 ,the sinking of mine shafts in certain ,belgian and ,french basins1 where the coal deposit is covered with thick strata of watery earth1 has from all times been considered as the most troublesome and delicate1 and often the most difficult operation1 of the miner's art4 ,of the few modern processes that have been employed for this purpose1 that of ,messrs4 ,kind and ,chaudron has been found most satisfactory1 although it leaves much to be desired where it is a question of traversing moving sand4 ,an interesting modification of this well-known process has recently been described by ,mr4 ,e4 ,chavatte1 in the ,bulletin de la ,societe ,industrielle du ,nord de la ,france4 ,two years ago the author had to sink a working shaft at ,quievrechain1 #aaa feet of which was to traverse a mass of moving and flowing sand1 inconsistent earth1 gravel1 and marls1 and proceeded as follows3 ,he first put down two beams1 ,a ,b 7,pl4 #a1 ,figs4 #b1 #c1 and #i71 each #hb feet in length and of #bjbj inch section in the center1 and upon these placed two others1 ,e ,f1 of #afaf inch section4 ,beneath the two first were inserted six joists1 c c c c c c1 about #hb feet in length and of #ad or #af inch section in the center4 ,finally these were strengthened at their extremities with two others1 d d1 about #hb feet in length4 ,all these timbers1 having been connected by tie bands and bolts1 constituted a rigid structure that covered a surface of nearly seven hundred square yards4 ,from the beams1 ,a ,b and ,e ,f1 there was suspended a red fir frame by means of thirty-four iron rods4 ,upon this frame1 which was entirely immersed in the moving sand1 there was established brick masonry 7,figs4 #a1 #b1 and #c74 ,as the ends of the timbers entered the latter1 and were connected by #a inch bolts1 they concurred in making the entire affair perfectly solid4 ,the frame1 ,k ,k1 was provided with an oaken ring1 which was affixed to it with bolts4 ,after this1 a cast iron tubbing1 having a cutting edge1 and being composed of rings #c4bh feet wide and made of six segments1 was lowered4 ,this tubbing was perfectly tight1 all the surfaces of the joints having been made even and provided with strips of lead one-tenth of an inch thick4 ,it weighed #d1jjj pounds to the running foot4 ,illustration3 ,,fig4 #a4--,section through ,a ,b4 ,,fig4 #b4--,plan4 ,,fig4 #c4--,section through ,c ,d4 ,,fig4 #e4--,section through ,e ,f of ,fig4 #d4 ,,figs4 #f ,,and #g4--,work ,prepared and finished4 ,,fig4 #aj4--,section through ,a ,b and ,c ,d of ,fig4 #ab4 ,,figs4 #aa #f ,,and #ab4--;,arrangement of jack-screw4 ,,fig4 #ac4--,section through ,a ,b and ,c ,d of ,fig4 #aa4 ,,plate ,i4--,,sinking ,a ,,mine ,,shaft4 ,it was first raised to a height of fifteen feet1 so as to cause it to enter the sand by virtue of its own gravity4 ,it thus penetrated to a depth of about twenty inches4 ,after this the workmen were ordered to man the windlasses and hoist out some of the sand4 ,this caused the tubbing to descend about eight inches more1 when it came to a standstill4 ,it was now loaded with #ag1jjj pounds of pig iron1 but in vain1 for it refused to budge4 ,mr4 ,chavatte therefore had recourse to a dredge with vertical axis1 constructed as follows3 ,upon a square axis1 ,a ,b 7,pl4 #b1 ,figs4 #a1 #b1 and #c71 provided with double cross braces1 ,c ,d1 and strengthened by diagonals1 were riveted1 by their upper extremities1 two cheeks1 ,g ,h1 whose lower extremities held the steel plates1 ,i ,j ,i' ,j'1 which1 in turn1 were fastened to the axis1 ,a ,b1 by their other extremities4 ,these plates were so inclined as to scrape the surface of the ground over which they were moved4 ,they each carried two bags made of coarse canvas and strengthened by five strong leather straps 7,figs4 #b and #d74 ,to the steel plates were riveted two plates of iron containing numerous apertures1 through which passed leather straps designed for fastening thereto the lower part of the mouth of the bags4 ,that portion of the mouth of the latter that was to remain open was fastened in the same way to two other plates1 ,x ,y1 ,x ,y 7,fig4 #a71 held between the lower cross-braces4 ,when the apparatus was revolved1 the plates scraped the earth to be removed1 and descended in measure as the latter entered the bags4 ,these bags1 when full1 were hooked1 by means of the five rings which they carried1 to the device shown in ,fig4 #h 7,pl4 #b71 and raised to the surface and emptied into cars4 ,the dredge was set in motion by four oak levers 7,figs4 #e and #f74 ,two of these were manned by workmen stationed upon the surface flooring1 and the other two by workmen upon the flooring in the tubbing4 ,the axis was elongated1 in measure as the apparatus descended1 by rods of the same dimensions fastened together by cast iron sleeves and bolts 7,fig4 #g74 ,the steel plates were not capable of acting alone1 even in cases where they operated in pure moving sand containing no pebbles1 for the sand was too compact to be easily scraped up by the steel1 and so it had to be previously divided4 ,for this purpose ,mr4 ,chavatte used rakes which were in form exactly like those of the extirpators1 ,u and ,v1 of ,figs4 #a1 #b1 and #c1 of ,pl4 #b1 except that the dividers carried teeth that were not so strong as those of the extirpators1 and that were set closer together4 ,these rakes were let down and drawn up at will4 ,they were maneuvered as follows3 ,the dredge descended with the extirpators pointing upward4 ,when their heads reached the level of the upper floor1 the tools were removed4 ,then the dredge was raised again4 ,in this way the extirpators lay upon the floor1 and1 if the lifting was continued1 they placed themselves in their working position1 in which they were fixed by the bolts ,a ,b ,c 7,fig4 #a74 ,after this1 the apparatus was let down and revolved4 ,the rakes divided the earth1 the scrapers collected it1 and the bags pocketed it4 ,the great difficulty was to cause the tubbing to descend vertically1 and also to overcome the enormous lateral pressure exerted upon it by the earth that was being traversed4 ,water put into the shaft helped somewhat1 but the great stress to be exerted had to be effected by means of powerful jack screws4 ,these were placed directly upon the tubbing1 and bore against strong beams whose extremities were inserted into the masonry4 ,as a usual thing it is not easy to use more than four or six such jacks1 since the number of beams that can be employed is limited1 owing to the danger of obstructing the mouth of the shaft4 ,yet twelve were used by ,mr4 ,chavatte1 and this number might have been doubled had it been necessary4 ,as we have seen1 the frame1 ,k ,k 7,pl4 #a1 ,fig4 #c71 was provided with an oak circle traversed by #cb bolts4 ,the length of these latter was two inches and a quarter longer than they needed to have been1 or they were provided with wooden collars of that thickness4 ,later on1 these collars were replaced with iron bars that held the wood against which the jacks bore in order to press the tubbing downward 7,pl4 #a1 ,figs4 #aj1 #aa1 #ab1 and #ac74 ,mr4 ,chavatte's great anxiety was to know whether he should succeed in causing the first section of tubbing to traverse the four feet of gravel2 for in case it did not pass1 he would be obliged to employ a second section of smaller diameter1 thus increasing the expense4 ,he was persuaded that the coarse gravel remaining in the side of the shaft would greatly retard the descent of the tubbing4 ,so he had decided to remove such obstructions at the proper moment through divers or a diving bell4 ,then an idea occurred to him that dispensed with all that trouble1 and allowed him to continue with the first section4 ,this was to place upon the dredge two claw-bars1 ,t 7,pl4 #b1 ,fig4 #c71 which effected the operation of widening with wonderful ease4 ,to do this it was only necessary to turn up the bags1 and revolve the apparatus during its descent4 ,the claw at the extremity of the bar pulled out everything within its reach1 and thus made an absolutely free passage for the tubbing4 ,the sands and gravels were passed by means of a single section of tubbing #ca feet in length1 which was not stopped until it had penetrated a stratum of white chalk to a depth of two yards4 ,this chalk had no consistency1 although it contained thin plates of quite large dimensions4 ,these were cut1 as if with a punch1 by means of the teeth of the extirpator4 ,it now remains to say a few words concerning the sinking of the shaft1 which1 after the operation of the dredge1 was continued by the process called natural level ,the work was not easy until a depth of #aaa feet had been reached4 ,up to this point it had been necessary to proceed with great prudence1 and retain the shifting earth by means of four iron plate tubes weighing #ed tons4 ,before finding a means of widening the work already done by the dredge1 ,mr4 ,chavatte was certain that he would have to use two sections of tubbing1 and so had given the first section a diameter of #af feet4 ,he could then greatly reduce the diameter1 and bring it to #ae feet as soon as the ground auger was used4 ,after two yards of soil had been removed from beneath the edge of the tubbing1 the earth began to give way4 ,seeing this1 ,mr4 ,chavatte let down a tube #ac feet in length and #ae4d in diameter4 ,the exterior of this was provided with #ab oak guides1 which sliding over the surface of the tubbing had the effect of causing the tube to descend vertically4 ,and this was necessary1 because this tube had to be driven down every time an excavation of half a yard had been made4 ,afterward1 a diameter of #ae4ce feet was proceeded with1 and the small central shaft of #d feet diameter was begun4 ,this latter had not as yet been sunk1 for fear of causing a fall of the earth4 ,next1 the earth was excavated to a depth of #h4b feet1 and a tube #af4d feet in length was inserted2 then a further excavation of #h4b feet was made1 and the tube driven home4 ,after this an excavation of #bf feet was made1 and a tube of the same length and #ad feet in diameter was driven down4 ,finally1 the shifting soil was finished with a fourth tube #ai feet in length and #ad feet in diameter4 ,a depth of #aaa feet had now been reached1 and the material encountered was solid white chalk4 ,from this point the work proceeded with a diameter of #ac4i feet to a depth of #dej feet4 ,the small shaft had been sunk directly to a depth of #dge feet4 ,at #dej feet the diameter was diminished by three inches4 ,then an advance of a foot was made1 and the diameter reduced by one and a half inch4 ,the reason for this reduction in the diameter and change in the mode of deepening was as follows3 ,the ,chaudron moss-box1 when it chances to reach its seat intact1 and can consequently operate well1 undoubtedly makes a good wedging4 ,but how many times does it not happen that it gets injured before reaching its destination8 ,besides1 as it often rests upon earth that has caved in upon its seat during the descent of the tubbing1 it gets askew1 and later on has to be raised on one side by means of jacks or other apparatus4 ,under such circumstances1 ,mr4 ,chavatte considered this moss-box as more detrimental than useful1 and not at all indispensable1 and so substituted beton for it1 as had previously been done by ,mr4 ,bourg1 director of the ,bois-du-,luc coal mines4 ,illustration3 ,,figs4 #a1 #b1 #c1 #f ,,and #d4--;,details of dredge4 ,,figs4 #e #f ,,and #f4--;,details of maneuvering lever4 ,,fig4 #g4--,mode of lengthening the axis of the dredge4 ,,fig4 #h4--;,hooks for lifting the dredge bags4 ,,fig4 #i4--;,arrangement of valves in the beton box4 ,,fig4 #aj4--;,device for centering the tubbing4 ,,plate ,,ii4 ,this engineer likewise suppressed the balancing column1 which is often a source of trouble in the descent of the tubbing1 and forced his tubbing to center itself with the shaft through a guide with four branches riveted under the false bottom that entered the small shaft 7,pl4 #b1 ,fig4 #aj74 ,mr4 ,bourg so managed that there remained an empty space of ten inches to fill in with beton4 ,mr4 ,chavatte had at first intended to proceed in the same way1 but the two last tubbings1 upon which he had not counted1 forced him to reduce the space to #e inches4 ,under such circumstances it was not prudent to employ the same means for guiding the base of the tubbing1 because1 if the central shaft had not exactly the same center as the large one1 there would have been danger of throwing the tubbing sideways and causing it to leak4 ,seeing which1 ,mr4 ,chavatte strengthened the lower part of the base ring and placed it upon another ring tapering downward1 and #bg inches in height 7,pl4 #a1 ,fig4 #e74 ,the object of this lower ring was to force the tubbing to remain concentric with the shaft1 to form a tight joint with its upper conical portion1 and to form a joint upon the seat with its lower flange1 so as to prevent the beton from flowing into the small shaft4 ,after the shaft was pumped out1 digging by hand was begun with a diameter of #ab feet4 ,after descending #bj inches an #haj inch curb was laid1 in order to consolidate the earth and prevent any movement of the tubbing4 ,then the excavating was continued to a depth of #ca inches1 and with a diameter of #i feet4 ,at this point another curb was put in for consolidating the earth4 ,finally1 the bottom was widened out as shown in ,fig4 #g1 so that three basal wedged curbs could be put in4 ,this done1 the false tubbing was put in place2 and finally1 when proceeding upward1 the last ring composed of twelve pieces was reached1 the earth was excavated and at once replaced with a collar composed of twelve pieces of oak tightened up by oak wedges4 ,each of these pieces was cemented separately and in measure as they were assembled4 ,through motive of economy no masonry was placed under the base of the three wedged curbs4 ,in fact1 by replacing this with a wedged curb of wood traversed by six bolts designed to fix the cast iron curb immediately above1 ,mr4 ,chavatte obtained a third curb that he would have had to have made of cast iron4 99 99 99 99 99 ,,on ,,the ,,elementary ,,principles ,,of ,,the ,,gas-,,engine4#a ,footnote #a3 ,a paper read before the ,gas ,institute1 ,manchester1 ,june1 #ahhe4 ,by ,,denny ,,lane1 of ,cork4 ,among the most useful inventions of the latter half of the nineteenth century the gas-engine holds a prominent place4 ,while its development has not been so brilliant or so startling as that which we can note in the employment of electricity1 it holds1 among the applications of heat1 the most important place of any invention made within that period4 ,even amid the contrivances by which1 in recent times1 the other forces of nature have been subdued to the uses of man1 there are only a few which rival the gas-engine in practical importance4 ,with regard to the steam-engine itself1 it is remarkable how little that is new has really been invented since the time of ,watt and ,woulfe4 ,in the specifications of the former can be shown completely delineated1 or fully foreshadowed1 nearly every essential condition of the economy and efficiency attained in our own days2 and it is only by a gradual survival of the fittest of the many contrivances which were made to carry out his broad ideas that the steam-engine of the present has attained its great economy4 ,it is but within the last fifty years that the laws of the relation between the different physical forces were first enunciated by ,justice ,grove1 and confirmed by the classical researches of ,dr4 ,joule--the one a lawyer1 working hard at his profession1 the other a man of business engaged in manufacture4 ,both are still living among us2 the latter having withdrawn from business1 while the former is a ,judge of the ,high ,court of ,justice4 ,i always regret that the claims of his profession have weaned ,justice ,grove from science2 for1 while it may be possible to find in the ranks of the ,bar many who might worthily occupy his place on the ,bench1 it would be hard to find among men of science any with as wide-reaching and practical philosophy as that which he owns4 ,the chemist demonstrated long since that it was impossible for man to create or destroy a single particle of ponderable matter2 but it remained for our own time to prove that it was equally impossible to create or destroy any of the energy which existed in nature as heat1 mechanical power1 electricity1 or chemical affinity4 ,all that it is in the power of man to do is to convert one of these forms into another4 ,this1 perhaps the greatest of all scientific discoveries since the time of ,newton1 was first1 ,i believe1 enunciated in #ahdb by ,grove1 in a lecture given at the ,london ,institution2 and it was experimentally proved by the researches of ,joule1 described in a paper which he read at the meeting of the ,british ,association which was held at ,cork--my native city--in #ahdc4 ,my friend ,dr4 ,sullivan1 now ,president of ,queen's ,college1 ,cork1 and ,i myself had the privilege of being two of a select audience of half a dozen people1 who alone took sufficient interest in the subject to hear for the first time developed the experimental proof of the theory which welds into one coherent system the whole physical forces of the universe1 and enables one of these to be measured by another4 ,one branch of the correlation of physical forces1 as it was termed by ,grove1 was the relation between mechanical power and heat1 and the convertibility of each into the other1 which1 under the name of ,thermodynamics1 has become one of the most important branches of practical science4 ,joule's first experiments clearly proved that each of these forms of energy was convertible into the other2 but some discrepancies arose in determining the exact equivalent of each4 ,his subsequent researches1 however1 clearly demonstrated the true relation between both4 ,taking as the unit of heat the amount which would be necessary to raise #a lb4 of water #a of ,fahrenheit's scale 7now called the ,english thermal unit71 he proved that this unit was equivalent to the mechanical power which would be required to raise #ggb lb4 #a foot1 or to raise #a lb4 #ggb ft4 perpendicularly against the force of gravity4 ,the heat-unit--the pound-degree--which ,i will distinguish by the ,greek letter theta1 is a compound unit of mass and temperature2 the second--the foot-pound f4p4--a compound unit of mass and space4 ,this equation1 called ,joule's equivalent1 or #a thermal unit #ggb foot-pounds1 is the foundation and the corner-stone of thermodynamics4 ,it is essential to understand the meaning of this equation4 ,it expresses the maximum effect of the given cause1 viz41 that if all the heat were converted into power1 or all the power were converted into heat1 #a thermal unit would produce #ggb foot-pounds1 or #ggb foot-pounds would raise #a lb4 of water #a ,fahr4 ,but there is never a complete conversion of any form of energy4 ,common solid coal may be partly converted into gases in a retort2 but some of the carbon remains unchanged1 and more is dissipated but not lost4 ,in the same way1 if ,i take five sovereigns to ,paris and convert them into francs1 and return to ,london and convert the francs into shillings1 ,i shall not have #ajj shillings1 but only perhaps #ie shillings4 ,but the five shillings have not been lost2 three of them remain in the ,french change de monnaies1 and two of them in the ,english exchange office4 ,i may have forfeited something1 but the world has forfeited nothing4 ,there remains in it exactly the same number of sovereigns1 francs1 and shillings as there was before ,i set out on my travels4 ,nothing has been lost1 but some of my money has been dissipated2 and the analogous case1 the dissipation of energy1 has formed the subject of more than one learned essay4 ,before the invention of the steam-engine1 the only powers employed in mechanics were those of wind and water mills1 and animal power4 ,in the first two1 no conversion of one force into another took place2 they were mere kinematic devices for employing the mechanical force already existing in the gale of wind and the head of water4 ,with regard to the power developed by man and other animals1 we had in them examples of most efficient heat-engines1 converting into power a large percentage of the fuel burnt in the lungs4 ,but animal power is small in amount1 and it is expensive for two reasons--first1 because the agents require long intervals of rest1 during which they still burn fuel2 and next1 because the fuel they require is very expensive4 ,a pound of bread or beef1 or oats or beans1 costs a great deal more than a pound of coal2 while it does not1 by its combustion1 generate nearly so much heat4 ,the steam-engine1 therefore1 took the place of animal power1 and for a long time stood alone2 and nearly all the motive power derived from heat is still produced by the mechanism which ,watt brought to such great efficiency in so short a time4 ,now the practical question for all designers and employers of heat-engines is to determine how the greatest quantity of motive force can be developed from the heat evolved from a given kind of fuel2 and coal being the cheapest of all1 we will see what are the results obtainable from it by the steam-engine4 ,in this we have three efficiencies to consider--those of the furnace1 the boiler1 and the cylinder4 ,first1 with respect to the furnace4 ,the object is to combine the carbon and the hydrogen of the coal with a sufficient quantity of the oxygen of the air to effect complete combustion into carbonic acid and water4 ,in order to do this1 we have to use a quantity of air much larger than is theoretically necessary1 and also to heat an amount of inert nitrogen five times greater than the necessary oxygen2 and we are therefore obliged to create a draught which carries away to the chimney a considerable portion of the heat developed4 ,the combustion1 moreover1 is never perfect2 and some heat is lost by conduction and radiation4 ,the principal loss is by hot gases escaping from the flues to the chimney4 ,even with well-set boilers1 the temperature in the chimney varies from #djj to #fjj ,fahr4 ,taking the mean of #ejj1 this would represent a large proportion of the total heat1 even if the combustion were perfect2 for1 as a general rule1 the supply of air to a furnace is double that which is theoretically necessary4 ,for our present purpose1 it will be sufficient to see how much the whole loss is1 without dividing it under the several heads of imperfect combustion1 radiation1 and convection1 by the heated gases passing to the chimney4 ,with a very good boiler and furnace each pound of coal evaporates #aj pounds of water from #fb ,fahr41 changing it into steam of #fe lb4 pressure at a temperature of #cab1 or #bej above that of the water from which it is generated4 ,besides these #bej1 each pound of steam contains #hid units of latent heat1 or #a1add units in all4 ,a very good condensing engine will work with #b4b lb4 of coal and #bb lb4 of steam per horse power per hour4 ,now4 #a lb4 of good coal will1 by its combustion1 produce #ad1jjj heat-units2 and the #b4b lb4 of coal multiplied by #ad1jjj represent #cj1hjjtheta4 ,of these we find in the boiler #bb #a1add1 or #be1afh units1 or about #ha per cent41 of the whole heat of combustion2 so that the difference 7#e1fcb units1 or #ah per cent47 has been lost by imperfect combustion1 radiation1 or convection4 ,the water required for condensing this quantity of steam is #eej lb42 and1 taking the temperature in the hot well as #ajb1 #eej lb4 have been raised #dj from #fb4 ,thus we account for #eej #dj #bb1jjj1 or 7say7 #ga per cent4 still remaining as heat4 ,if we add this #ga per cent4 to #ah per cent4 we have #ij per cent41 and there remain only #aj per cent4 of the heat that can possibly have been converted into power4 ,but some of this has been lost by radiation from steam-pipes1 cylinder1 etc4 ,allowing but #a per cent4 for this1 we have only #i per cent4 as the efficiency of a really good condensing engine4 ,this estimate agrees very closely with the actual result2 for the #b4b lb4 of coal would develop #cj1hjjtheta2 and this1 multiplied by ,joule's equivalent1 amounts to nearly #bd millions of foot-pounds4 ,as #a horse power is a little less than #b million foot-pounds per hour1 only one-twelfth1 or a little more than #h per cent4 of the total heat is converted2 so that whether we look at the total quantity of heat which we show unconverted1 or the total heat converted1 we find that each supplements and corroborates the other4 ,if we take the efficiency of the engine alone1 without considering the loss caused by the boiler1 we find that the #be1afhtheta which entered the boiler should have given #ai1dbi1fif foot-pounds2 so that the #b millions given by the engine represent about #aj per cent4 of the heat which has left the boiler4 ,the foregoing figures refer to large stationary or marine engines1 with first-rate boilers4 ,when1 however1 we come to high-pressure engines of the best type1 the consumption of coal is twice as much2 and for those of any ordinary type it is usual to calculate #a cubic foot1 or #fb lb41 of water evaporated per horse power4 ,this would reduce the efficiency to about #f per cent4 for the best1 and #c per cent4 for the ordinary non-condensing engines2 and if to this we add the inefficiency of some boilers1 it is certain that many small engines do not convert into power more than #b per cent4 of the potential energy contained in the coal4 ,at one time the steam-engine was threatened with serious rivalry by the hot-air engine4 ,about the year #ahaf the ,rev4 ,mr4 ,stirling1 a ,scotch clergyman1 invented one which a member of this ,institute 7,mr4 ,george ,anderson7 remembers to have seen still at work at ,dundee4 ,the principle of it was that a quantity of air under pressure was moved by a mass1 called a displacer1 from the cold to the hot end of a large vessel which was heated by a fire beneath and cooled by a current of water above4 ,the same air was alternately heated and cooled1 expanded and contracted2 and by the difference of pressure moved the piston in a working cylinder4 ,in this arrangement the furnace was inefficient4 ,as only a small portion of heat reached the compressed air1 the loss by radiation was very great1 and the wear and tear exceedingly heavy4 ,this system1 with some modifications1 was revived by ,rankine1 ,ericsson1 ,laubereau1 ,ryder1 ,buckett1 and ,bailey4 ,siemens employed a similar system1 only substituting steam for air4 ,another system1 originally proposed by ,sir ,george ,cayley1 consisted in compressing by a pump cold air which was subsequently passed partly through a furnace1 and1 expanding1 moved a larger piston at the same pressure2 and the difference of the areas of the pistons multiplied by the pressure common to both represented the indicated power4 ,this principle was subsequently developed by a very able mechanic1 ,mr4 ,wenham2 but his engine never came much into favor4 ,the only hot-air engines at present in use are ,ryder's1 ,buckett's1 and ,bailey's1 employed to a limited extent for small powers4 ,i have not said anything of the thermal principles involved in the construction of these engines1 as they are precisely the same as those affecting the subject of the present paper4 ,before explaining the principle upon which the gas-engine and every other hot-air engine depends1 ,i shall remind you of a few data with which most of you are already familiar4 ,the volume of every gas increases with the temperature2 and this increase was the basis of the air thermometer--the first ever used4 ,it is to be regretted that it was not the foundation of all others2 for it is based on a physical principle universally applicable4 ,although the volume increases with the temperature1 it does not increase in proportion to the degrees of any ordinary scale1 but much more slowly4 ,now1 if to each of the terms of an arithmetical series we add the same number1 the new series so formed increases or decreases more slowly than the original2 and it was discovered that1 by adding #dfa to the degrees of ,fahrenheit's scale1 the new scale so formed represented exactly the increment of volume caused by increase of temperature4 ,this scale1 proposed by ,sir ,w4 ,thomson in #ahdh1 is called the scale of absolute temperature4 ,its zero1 called the absolute zero1 is #dfa below the zero of ,fahrenheit1 or #dic below the freezing point of water2 and the degree of heat measured by it is termed the absolute temperature4 ,it is often convenient to refer to #ci ,fahr4 7which happens to be the point at which water attains its maximum density71 as this is the same as #ejj absolute2 for1 counting from this datum level1 a volume of air expands exactly #a per cent4 for #e1 and would be doubled at #a1jjj absolute1 or #eci ,fahr4 ,whenever any body is compressed1 its specific heat is diminished2 and the surplus portion is1 as it were1 pushed out of the body--appearing as sensible heat4 ,and whenever any body is expanded1 its specific heat is increased2 and the additional quantity of heat requisite is1 as it were1 sucked in from surrounding bodies--so producing cold4 ,this action may be compared to that of a wet sponge from which1 when compressed1 a portion of the water is forced out1 and when the sponge is allowed to expand1 the water is drawn back4 ,this effect is manifested by the increase of temperature in air-compressing machines1 and the cold produced by allowing or forcing air to expand in air-cooling machines4 ,at #ci ,fahr41 #a lb4 of air measures #ab cubic feet4 ,let us suppose that #a lb4 of air at #ci ,fahr4 #ejj absolute1 is contained in a non-conducting cylinder of #a foot area and #ab feet deep under a counterpoised piston4 ,the pressure of the atmosphere on the piston #add square inches #ad4g lb41 or #b1aaf lb4 ,if the air be now heated up to #eci ,fahr4 #a1jjj absolute1 and at the same time the piston is not allowed to move1 the pressure is doubled2 and when the piston is released1 it would rise #ab feet1 provided that the temperature remained constant1 and the indicator would describe a hyperbolic curve 7called an isothermal7 because the temperature would have remained equal throughout4 ,but1 in fact1 the temperature is lowered1 because expansion has taken place1 and the indicator curve which would then be described is called an adiabatic curve1 which is more inclined to the horizontal line when the volumes are represented by horizontal and the pressures by vertical co-ordinates4 ,in this case it is supposed that there is no conduction or transmission 7diabasis7 of heat through the sides of the containing vessel4 ,if1 however1 an additional quantity of heat be communicated to the air1 so as to maintain the temperature at #a1jjj absolute1 the piston will rise until it is #ab feet above its original position1 and the indicator will describe an isothermal curve4 ,now mark the difference4 ,when the piston was fixed1 only a heating effect resulted2 but when the piston moved up #ab feet1 not only a heating but a mechanical1 in fact1 a thermodynamic1 effect was produced1 for the weight of the atmosphere 7#b1aaf lb47 was lifted #ab feet #bf1dej foot-pounds4 ,the specific heat of air at constant pressure has been proved by the experiments of ,regnault to be #j4bcgh1 or something less than one-fourth of that of water--a result arrived at by ,rankine from totally different data4 ,in the case we have taken1 there have been expended #ejj #j4bcgh1 or 7say7 #aah4itheta to produce #bf1dej f4p4 ,each unit has therefore produced 7#bf1dej _/ #aah4j7 #bbb4e f4p41 instead of #ggb f4p41 which would have been rendered if every unit had been converted into power4 ,we therefore conclude that 7#bbb4e _/ #ggb7 #bi per cent4 of the total heat has been converted4 ,the residue1 or #ga per cent41 remains unchanged as heat1 and may be partly saved by a regenerator1 or applied to other purposes for which a moderate heat is required4 ,the quantity of heat necessary to raise the heat of air at a constant volume is only #ga per cent4 of that required to raise to the same temperature the same weight of air under constant pressure4 ,this is exactly the result which ,laplace arrived at from observations on the velocity of sound1 and may be stated thus-- ,specific ,foot- ,per heat4 pounds4 cent4 ,kp #a lb4 of air at constant pressure #j4bcgh #ggb #ahc4e #ajj ,kv #a lb4 of air at constant volume #j4afhh #ggb #acj4c #ga ------ --- ----- --- ,difference1 being heat converted into power #j4jfij #ggb #ec4b #bi ,or1 in a hot-air engine without regeneration1 the maximum effect of #a lb4 of air heated #a ,fahr4 would be #ec4b f4p4 ,the quantity of heat ,ky necessary to heat air under constant volume is to ,kv1 or that necessary to heat it under constant pressure1 as #ga3ajj1 or as #a3a4djh1 or very nearly as #a3,,sqrt7#b7--;a result which was arrived at by ,masson from theoretical considerations4 ,the #ga per cent4 escaping as heat may be utilized in place of other fuel2 and with the first hot-air engine ,i ever saw1 it was employed for drying blocks of wood4 ,in the same way1 the unconverted heat of the exhaust steam from a high-pressure engine1 or the heated gases and water passing away from a gas-engine1 may be employed4 ,illustration ,we are now in a position to judge what is the practical efficiency of the gas-engine4 ,some years since1 in a letter which ,i addressed to ,engineering1 and which also appeared in the ,journal of ,gas ,lighting1#b ,i showed 7,i believe for the first time7 that1 in the ,otto-,crossley engine1 #ah per cent4 of the total heat was converted into power1 as against the #h per cent4 given by a very good steam-engine4 ,about the end of #ahhc a very elaborate essay1 by ,m4 ,witz1 appeared in the ,annales de ,chimie et de ,physique1 reporting experiments on a similar engine1 which gave an efficiency somewhat lower4 ,early in #ahhd there appeared in ,van ,nostrand's ,engineering ,magazine a most valuable paper1 by ,messrs4 ,brooks and ,steward1 with a preface by ,professor ,thurston1#c in which the efficiency was estimated at #ag to #ah per cent4 of the total heat of combustion4 ,both these papers show what ,i had no opportunity of ascertaining1 that is1 what becomes of the #hb per cent4 of heat which is not utilized--information of the greatest importance1 as it indicates in what direction improvement may be sought for1 and how loss may be avoided4 ,but1 short as is the time that has elapsed since the appearance of these papers1 you will find that progress has been made1 and that a still higher efficiency is now claimed4 ,footnote #b3 ,see ,journal1 vol4 xxxv1 pp4 #ia1 #acc4 ,footnote #c3 ,ibid41 vol4 xliii41 pp4 #gjc1 #gdd4 ,when ,i first wrote on this subject1 ,i relied upon some data which led me to suppose that the heating power of ordinary coal gas was higher than it really is4 ,at our last meeting1 ,mr4 ,hartley proved1 by experiments with his calorimeter1 that gas of #af or #ag candles gave only about #fcj units of heat per cubic foot4 ,now1 if all this heat could be converted into power1 it would yield #fcj #ggb1 or #dhf1cfj f4p42 and it would require only #a1ihj1jjj _/ #dhf1cfj #d4jg cubic feet to produce #a indicated horse power4 ,some recent tests have shown that1 with gas of similar heating power1 #ah cubic feet have given #a indicated horse power1 and therefore #d4jg _/ #ah #bb4f of the whole heat has been converted--a truly wonderful proportion when compared with steam-engines of a similar power1 showing only an efficiency of #b to #d per cent4 ,the first gas-engine which came into practical use was ,lenoir's1 invented about #ahff1 in which the mixture of gas and air drawn in for part of the stroke at atmospheric pressure was inflamed by the spark from an induction coil4 ,this required a couple of cells of a strong ,bunsen battery1 was apt to miss fire1 and used about #ij cubic feet of gas per horse power4 ,this was succeeded by ,hugon's engine1 in which the ignition was caused by a small gas flame1 and the consumption was reduced to #hj cubic feet4 ,in #ahfd ,otto's atmospheric engine was invented1 in which a heavily-loaded piston was forced upward by an explosion of gas and air drawn in at atmospheric pressure4 ,in its upward stroke the piston was free to move2 but in its downward stroke it was connected with a ratchet1 and the partial vacuum formed after the explosion beneath the piston1 together with its own weight in falling1 operated through a rack1 and caused rotation of the flywheel4 ,this engine 7which1 in an improved form1 uses only about #bj cubic feet of gas7 is still largely employed1 some #a1fjj having been constructed4 ,the great objection to it was the noise it produced1 and the wear and tear of the ratchet and rack arrangements4 ,in #ahgf the ,otto-,crossley silent engine was introduced4 ,as you are aware1 it is a single-acting engine1 in which the gas and air are drawn in by the first outward1 and compressed by the first inward stroke4 ,the compressed mixture is then ignited2 and1 being expanded by heat1 drives the piston outward by the second outward stroke4 ,near the end of this stroke the exhaust-valve is opened1 the products of combustion partly escape1 and are partly driven out by the second inward stroke4 ,i say partly1 for a considerable clearance space1 equal to #ch per cent4 of the whole cylinder volume1 remains unexhausted at the inner end of the cylinder4 ,when working to full power1 only one stroke out of every four is effective2 but this engine works with only #ah to #bb cubic feet of gas per horse power4 ,up to the present time ,i am informed that about #ah1jjj of these engines have been manufactured4 ,several other compression engines have been introduced1 of which the best known is ,mr4 ,dugald ,clerk's1 using about #bj feet of ,glasgow cannel gas4 ,it gives one effective stroke for every revolution2 the mixture being compressed in a separate air-pump4 ,but this arrangement leads to additional friction2 and the power measured by the brake is a smaller percentage of the indicated horse power than in the ,otto-,crossley engine4 ,a number of gas engines--such as ,bisschop's 7much used for very small powers71 ,robson's 7at present undergoing transformation in the able hands of ,messrs4 ,tangye71 ,korting's1 and others--are in use2 but1 so far as ,i can learn1 all require a larger quantity of gas than those previously referred to4 ,illustration3 ,,otto ,,atmospheric ,,gas ,,engine4 ,illustration3 ,,clerck',s ,,gas ,,engine1 #f ,,horse ,,power4 ,illustration3 ,,otto-,,crossley ,,gas ,,engine1 #af ,h4,p4 ,consumption #ag4f cubic feet of #af-;candle gas per theoretical horse power per hour4 ,average pressure1 #ij4d constant1 4#efh theoretical horse power per pound #ej4h theoretical horse power4 ,illustration3 ,,atkinson',s ,,differential ,,gas ,,engine1 #h ,h4,p4 ,i have all along spoken of efficiency as a percentage of the total quantity of heat evolved by the fuel2 and this is1 in the eyes of a manufacturer1 the essential question4 ,other things being equal1 that engine is the most economical which requires the smallest quantity of coal or of gas4 ,but men of science often employ the term efficiency in another sense1 which ,i will explain4 ,if ,i wind a clock1 ,i have spent a certain amount of energy lifting the weight4 ,this is called energy of position2 and it is returned by the fall of the weight to its original level4 ,in the same way if ,i heat air or water1 ,i communicate to it energy of heat1 which remains potential as long as the temperature does not fall1 but which can be spent again by a decrease of temperature4 ,in every heat-engine1 therefore1 there must be a fall from a higher to a lower temperature2 otherwise no work would be done4 ,if the water in the condenser of a steam-engine were as hot as that in the boiler1 there would be equal pressure on both sides of the piston1 and consequently the engine would remain at rest4 ,now1 the greater the fall1 the greater the power developed2 for a smaller proportion of the heat remains as heat4 ,if we call the higher temperature ,t and the lower ,t' on the absolute scale1 ,t - ,t' is the difference2 and the ratio of this to the higher temperature is called the efficiency4 ,this is the foundation of the formula we meet so often3 ,e 7,t - ,t'7_/,t4 ,a perfect heat-engine would1 therefore1 be one in which the temperature of the absolute zero would be attained1 for 7,t - ,o7_/,t #a4 ,this low temperature1 however1 has never been reached1 and in all practical cases we are confined within much narrower limits4 ,taking the case of the condensing engine1 the limits were #cab to #ajb1 or #ggc and #efc absolute1 respectively4 ,the equation then becomes 7#ggc - #efc7_/ggc #baj_/ggc or 7say7 #bg per cent4 ,with non-condensing engines1 the temperatures may be taken as #cab and #bab1 or #ggc and #fgc absolute respectively4 ,the equation then becomes 7#ggc - #fgc7_/ggc #ajj_/ggc1 or nearly #ac per cent4 ,the practical efficiencies are not nearly this1 but they are in about the same ratio--#bg_/ac4 ,if1 then1 we multiply the theoretical efficiencies by #j4cg1 we get the practical efficiencies1 say #aj per cent4 and #e per cent42 and it is in the former sense that ,m4 ,witz calculated the efficiency of the steam-engine at #ce per cent4--a statement which1 ,i own1 puzzled me a little when ,i first met it4 ,these efficiencies do not take any account of loss of heat before the boiler4 ,in the case of the gas-engine1 the question is much more complicated on account of the large clearance space and the early opening of the exhaust4 ,the highest temperature has been calculated by the ,american observers at #c1ddc absolute1 and the observed temperature of the exhaust gases was #a1bbi4 ,the fraction then becomes 7#cddc - #abbi7_/cddc #fd per cent4 ,if we multiply this by #j4cg1 as we did in the case of the steam-engine1 we get #bc4g per cent41 or approximately the same as that arrived at by direct experience4 ,indeed1 if the consumption is1 as sometimes stated1 less than #ah feet1 the two percentages would be exactly the same4 ,i do not put this forward as scientifically true2 but the coincidence is at least striking4 ,i have spoken of the illuminating power of the gas as of importance2 for the richer gases have also more calorific power1 and an engine would1 of course1 require a smaller quantity of them4 ,the heat-giving power does not1 however1 vary as the illuminating power1 but at a much slower rate2 and1 adopting the same contrivance as that on which the absolute scale of temperature is formed1 ,i would suggest a formula of the following type3 ,h ,c 7,i ,k71 in which ,h represents the number of heat-units given out by the combustion of #a cubic foot of gas1 ,i is the illuminating power in candles1 and ,c and ,k two constants to be determined by experiment4 ,if we take the value for motive power of the different qualities of gas as given in ,mr4 ,charles ,hunt's interesting paper in our ,transactions for #ahhb1 ,c might without any great error be taken as #bb and ,k as #g4e4 ,with ,pintsch's oil gas1 however1 as compared with coal gas1 this formula does not hold2 and ,c should be taken much lower1 and ,k much higher than the figures given above4 ,that is to say1 the heating power increases in a slower progression4 ,the data available1 however1 are few2 but ,i trust that ,mr4 ,hartley will on this1 as he has done on so many other scientific subjects1 come to our aid4 ,i will now refer to the valuable experiments of ,messrs4 ,brooks and ,steward1 which were most carefully made4 ,everything was measured--the gas by a #fj light1 and the air by a #cjj light meter2 the indicated horse power1 by a steam-engine indicator2 the useful work1 by a ,prony brake2 the temperature of the water1 by a standard thermometer2 and that of the escaping gases1 by a pyrometer4 ,the gas itself was analyzed2 and its heating power calculated1 from its composition1 as #fag4etheta4 ,its specific gravity was 4#dfd2 and the volume of air was about seven times that of the gas used 7or one-eighth of the mixture71 and was only #aa per cent4 by weight more than was needed for perfect combustion4 ,the results arrived at were as follows3 ,per cent4 ,converted into indicated horse power1 including friction1 etc4 #ag4j ,escaped with the exhaust gas4 #ae4e ,escaped in radiation4 #ae4e ,communicated to water in the jacket4 #eb4j ,it will thus be seen that more than half of the heat is communicated to the water in the jacket4 ,now1 this is the opposite of the steam-engine1 where the jacket is used to transmit heat to the cylinder1 and not from it4 ,this cooling is rendered necessary1 because without it the oil would be carbonized1 and lubrication of the cylinder rendered impossible4 ,indeed1 a similar difficulty has occurred with all hot-air engines1 and is1 ,i think1 the reason they have not been more generally adopted4 ,i felt this so strongly that1 for some time after the introduction of the gas-engine1 ,i was very cautious in recommending those who consulted me to adopt it4 ,i was afraid that the wear and tear would be excessive4 ,i have1 however1 for some time past been thoroughly satisfied that this fear was needless2 as ,i am satisfied that a well-made gas-engine is as durable as a steam-engine1 and the parts subject to wear can be replaced at moderate cost4 ,we have no boiler1 no feed pump1 no stuffing-boxes to attend to--no water-gauges1 pressure-gauges1 safety-valve1 or throttle-valve to be looked after2 the governor is of a very simple construction2 and the slide-valves may be removed and replaced in a few minutes4 ,an occasional cleaning out of the cylinder at considerable intervals is all the supervision that the engine requires4 ,the very large percentage of heat absorbed by the water-jacket should point out to the ingenuity of inventors the first problem to be attacked1 viz41 how to save this heat without wasting the lubricant or making it inoperative2 and in the solution of this problem1 ,i look for the most important improvement to be expected in the engine4 ,the most obvious contrivance would be some sort of intercepting shield1 which would save the walls of the cylinder and the rings of the piston from the heat of the ignited gases4 ,i have just learned that something of the kind is under trial4 ,another solution may possibly be found in the employment of a fluid piston2 but here we are placed in a dilemma between the liquids that are decomposed and the metals that are oxidized at high temperatures4 ,next1 the loss by radiation--#ae per cent4--seems large2 but this is to be attributed to the fact that the inside surface of the cylinder is at each inward stroke exposed to the atmosphere--an influence which contributes to the cooling necessary for lubrication4 ,the remaining #ae per cent41 which is carried away by the exhaust1 is small compared with the proportion passing away with the exhaust steam of a high-pressure or the water of a condensing engine4 ,as the water in the jacket can be safely raised to #bab ,fahr41 the whole of the jacket heat can be utilized where hot water is required for other purposes2 and this1 with the exhaust gases1 has been used for drying and heating purposes4 ,with such advantages1 it may be asked3 ,why does not the gas-engine everywhere supersede the steam-engine8 ,my answer is a simple one3 ,the gas we manufacture is a dear fuel compared with coal4 ,ordinary coal gas measures #cj cubic feet to the pound2 and #a1jjj cubic feet1 therefore1 weigh #cc lb4 ,taking the price at #bs4 #i;d4 per #a1jjj cubic feet1 it costs #a;d4 per lb4 ,the #cj cubic feet at #fcjtheta give #ai1jjjtheta all available heat4 ,although good coal may yield #ad1jjj units by its combustion1 only about #aa1jjj of these reach the boiler2 so that the ratio of the useful heat is #aa_/ai4 ,the thermal efficiency of the best non-condensing engine to that of the gas-engine is in the ratio #d_/bb4 ,multiplying together these two ratios1 we get #aa #d #dd -- x ------- ---- #ai #bba_/b #d4bh ,that is1 speaking roughly1 #a lb4 of gas gives about ten times as much power as #a lb4 of coal does in a good non-condensing engine4 ,but at #ahs4 #h;d4 a ton we get #aj lb4 of coal for #a;d42 so that with these figures the cheapness of the coal would just compensate for the efficiency of the gas4 ,as to the waste heat passing away from the engine being utilized1 here the gas-engine has no advantage2 and1 so far as this is concerned1 the gas is about eight times dearer than coal4 ,the prices of gas and coal vary so much in different places that it is hard to determine in what cases gas or coal will be the dearer fuel1 considering this point alone4 ,but there are other kinds of non-illuminating gases--such as ,wilson's1 ,strong's1 and ,dowson's--which are now coming into use2 and at ,messrs4 ,crossley's works you will have an opportunity of seeing a large engineering factory employing several hundred mechanics1 and without a chimney1 in which every shaft and tool is driven by gas-engines supplied by ,dowson's gas1 and in which the consumption of coal is only #a4b lb4 per indicated horse power4 ,the greatest economy ever claimed for the steam-engine was a consumption of #a4f lb42 and this with steam of very high pressure1 expanded in three cylinders successively4 ,thus in a quarter of a century the gas-engine has beaten in the race the steam-engine2 although from ,watt's first idea of improvement1 nearly a century and a quarter have elapsed4 ,as regards the steam-engine1 it is the opinion of competent authorities that the limits of temperature between which it works are so restricted1 and so much of the heat is expended in producing a change of state from liquid to vapor1 that little further improvement can be made4 ,with respect to gas-engines1 the limits of temperature are much further apart4 ,a change of state is not required1 and so very great improvement may still be looked for4 ,it is not impossible even that some of the younger members of our body may live to see that period foretold by one of the greatest of our civil engineers--that happy time when boiler explosions will only be matters of history2 that period1 not a millennium removed by a thousand years1 but an era deferred perhaps by only half a dozen decades1 when the use of the gas-engine will be universal1 and a steam-engine can be found only in a cabinet of antiquities4 ,discussion4 ,the ,president said this was a very delightful paper2 and nothing could be finer than ,mr4 ,lane's description of the conversion of heat into power1 and the gradual growth of theory into practical work4 ,mr4 ,w4 ,foulis 7,glasgow7 agreed that it was admirable2 but it required to be read to be thoroughly appreciated4 ,when members were able to read it1 they would find ,mr4 ,lane had given a very clear description of the elementary principles of thermo-dynamics in their relation to the gas-engine and the steam-engine4 ,there was very little in the paper to raise discussion2 but ,mr4 ,lane had made exceedingly clear how the present loss in a gas-engine was occasioned1 and had also shown how1 in the future development of the engine1 the loss might be saved1 and the engine rendered more efficient4 ,mr4 ,h4,p4 ,holt 7of ,messrs4 ,crossley ,bros41 ,limited7 said he could indorse everything ,mr4 ,lane had said4 ,he had found the paper most interesting and instructive even to himself1 though he had some little practical experience of gas-engines1 and was supposed to know a little about them4 ,he did not pretend to be able to teach other people2 but if he could say anything as to indicator cards1 or answer any questions1 he should be happy to do so4 7,he then described the indicator diagram of the atmospheric gas-engine47 ,in this engine the proportion of the charging stroke to the whole sweep of the piston was about #aj per cent42 and as the charge drawn in consisted of about #aj per cent4 of gas1 about #a-ajj of the total sweep of the piston was composed of the gas4 ,mr4 ,foulis asked what proportion the power indicated on the diagram bore to the power indicated on the brake in the atmospheric engine4 ,mr4 ,holt said unfortunately he had not any figures with him which would give this information2 and it was so long since he had anything practically to do with this form of engine1 that he should not like to speak from memory4 ,he might add that the largest size of gas-engine made 7of about #ajj horse power indicated7 was at work at ,messrs4 ,edwin ,butterworth and ,co4's1 of ,manchester4 ,it was now driven by ordinary coal gas2 but ,dowson plant was to be put up very shortly in order to reduce the cost of working1 which1 though not excessive1 would be still more economical with the ,dowson gas--probably only about #cjs4 per week4 ,the present cost was about #d per week1 though it was not working always at full power4 ,mr4 ,t4 ,holgate 7,batley7 said he thought it was generally understood1 by those who had studied the subject1 that the adoption of compression of the gaseous mixture before ignition had1 so far1 more than anything else1 contributed to the improved working of gas-engines4 ,this fact had not been sufficiently brought out in the paper1 although ,mr4 ,lane had clearly indicated some of the directions in which further improvements were likely to obtain4 ,gas engineers were largely indebted to ,mr4 ,dugald ,clerk for the statement he had made of the theory of the gas-engine4#d ,mr4 ,lane had given some figures1 arrived at by ,messrs4 ,brooks and ,steward1 from experiments made in ,america2 but1 prior to these ,mr4 ,clerk had given others which were in the main in accordance with them4 ,professor ,kennedy had also made experiments1 the results of which agreed with them4#e ,the extent of the loss by the cooling water was thus well ascertained2 and it was no doubt by a reduction of this loss that further improvement in the working of gas-engines would eventually be obtained4 ,footnote #d3 ,see ,journal1 vol4 xxxix41 p4 #fdh4 ,footnote #e3 ,ibid41 vol4 xl41 p4 #iee4 ,mr4 ,j4 ,paterson 7,warrington7 expressed his appreciation of the paper1 as one of exceptional interest and value4 ,he said he did not rise with a view to make any observations thereon4 ,the analysis of first principles required more matured consideration and thought than could be given to it here4 ,the opinion1 however1 he had formed of the paper placed it beyond the reach of criticism4 ,it was now many years since his attention had been drawn to the name of ,denny ,lane2 and everything that had come from his facile pen conveyed sound scientific conclusions4 ,the paper to which they had just listened was no exception4 ,it was invested with great interest1 and would be regarded as a valuable contribution to the ,transactions of the ,institute4 ,mr4 ,lane1 in reply1 thanked the members for the kind expressions used with respect to his paper4 ,his object in writing it was that any one who had not paid any attention to the subject before should be able to understand thoroughly the principles on which gas and hot-air engines operated2 and he believed any one who read it with moderate care would perfectly understand all the essential conditions of the gas-engine4 ,he might mention that not long after the thermo-dynamic theory was so far developed as to determine the amount of heat converted into power1 a very eminent ,french ,engineer--,m4 ,hirn--conducted some experiments on steam-engines at a large factory1 and thought he could account for the whole heat of combustion in the condensed water and the heat which passed away2 so much so that he actually doubted altogether the theory of thermo-dynamics4 ,however1 being open to conviction1 he made further experiments1 and discovered that he had been in error1 and ultimately became one of the most energetic supporters of the theory4 ,this showed how necessary it was to be careful before arriving at a conclusion on such a subject4 ,he had endeavored1 as far as the nature of the case allowed1 to avoid any scientific abstractions1 because he knew that when practical men came to theory--x's and y's1 differentials1 integrals1 and other mathematical formul--they were apt to be terrified4 ,the ,president said it was like coming down to every day life to say that it was important that gas managers should be familiar with the appliances used in the consumption of gas1 and should be able1 when called upon1 to give an intelligent description of their method of working4 ,a study of ,mr4 ,lane's paper would reveal many matters of interest with regard to this wonderful motor1 which was coming daily more and more into use1 not only to the advantage of gas manufacturers1 but of those who employed them4 99 99 99 99 99 ,m4 ,,meizel',s ,,reciprocating ,,exhauster4 ,at the recent ,congress of the ,societe ,technique de l',industrie du ,gaz en ,france1 ,m4 ,meizel1 ,chief ,engineer of the ,st4 ,etienne ,gas ,works1 described a new exhauster devised by him on the reciprocating principle1 and for which he claims certain advantages over the appliances now in general use4 ,exhausters constructed on the above-named principle have hitherto1 ,m4 ,meizel says1 been costly to fit up1 owing to the necessity for providing machinery and special mechanism for the transmission of motion4 ,this has prevented the employment of cylinders of large dimensions2 and1 consequently1 when the quantity of gas to be dealt with has been considerable1 the number of exhausters has had to be increased4 ,the result of this has been inconvenience1 which has led to a preference being shown for other kinds of exhausters1 notwithstanding the manifest advantages which1 in ,m4 ,meizel's opinion1 those of the reciprocating type possess4 ,the improvement which he has effected in these appliances consists in the application to them of cylinders working automatically2 and the general features of the arrangement are shown in the accompanying illustrations4 ,illustration3 ,,improved ,,reciprocating ,,gas ,,exhauster4 ,the principal advantages to be gained by the use of this exhauster are stated by ,m4 ,meizel to be the following3 ,considerably less motive force is necessary than is the case with other exhausters1 which require steam engines and all the auxiliary mechanism for the transmission of power4 ,by its quiet and regular action1 it prevents oscillation and unsteadiness in the flow of gas in the hydraulic main1 as well as in the pipes leading therefrom--a defect which has been found to exist with other exhausters4 ,the bells1 being of large area1 serve the purpose of a condenser2 and as1 owing to its density1 the tar falls to the bottom of the lower vessels1 which are filled with water1 contact between the gas and tar is avoided4 ,although the appliance is of substantial construction1 its action is so sensitive that it readily adapts itself to the requirements of production4 ,it may be placed in the open air2 and therefore its establishment is attended with less outlay than is the case with other exhausters1 which have to be placed under cover1 and provided with driving machinery and1 of course1 a supply of steam4 ,the total superficial area of the exhauster above described1 including the governor1 is #aej square feet2 and its capacity per #bd hours is #bcj1jjj cubic feet4 ,it works silently1 with an almost entire absence of friction2 and consequently there are few parts which require lubrication4 ,exhausters of this type 7which1 ,m4 ,meizel says1 could be made available for ventilation purposes1 in case of necessity7 may be constructed of all sizes1 from #ejj cubic feet per hour upward4 99 99 99 99 99 ,,automatic ,,siphon ,,for ,,irrigation4 ,when1 at an elevated point in a meadow1 there exists a spring or vein of water that cannot be utilized at a distance1 either because the supply is not sufficient1 or because of the permeability of the soil1 it becomes very advantageous to accumulate the water in a reservoir1 which may be emptied from time to time through an aperture large enough to allow the water to flow in abundance over all parts of the field4 ,illustration3 ,,giral',s ,,automatic ,,siphon4 ,the storing up of the water permits of irrigating a much greater area of land1 and has the advantage of allowing the watering to be effected intermittingly1 this being better than if it were done continuously4 ,but this mode of irrigating requires assiduous attention4 ,it is necessary1 in fact1 when the reservoir is full1 to go and raise the plug1 wait till the water has flowed out1 and then put in the plug again as accurately as possible--a thing that it is not always easy to do4 ,the work is a continuous piece of drudgery1 and takes just as much the longer to do in proportion as the reservoir is more distant from one's dwelling4 ,in order to do away with this inconvenience1 ,mr4 ,giral1 of ,langogne 7,lozere71 has invented a sort of movable siphon that primes itself automatically1 however small be the spring that feeds the reservoir in which it is placed4 ,the apparatus 7see figure7 consists of an elbowed pipe1 ,c ,a ,b ,d ,e1 of galvanized iron1 whose extremity1 ,c1 communicates with the outlet1 ,r1 where it is fixed by means of a piece of rubber of peculiar form that allows the other extremity1 ,b ,d ,e1 to revolve around the axis1 ,k1 while at the same time keeping the outlet pipe hermetically closed4 ,this rubber1 whose lower extremity is bent back like the bell of a trumpet1 forms a washer against which there is applied a galvanized iron ring that is fixed to the mouth of the outlet pipe by means of six small screws4 ,this ring is provided with two studs which engage with two flexible thimbles1 ,k and ,l1 that are affixed to the siphon by four rivets4 ,these studs and thimbles1 as well as the screws1 are likewise galvanized4 ,between the branches1 ,a ,b ,d ,e1 of the pipe there is soldered a sheet of galvanized iron1 which forms isolatedly a receptacle or air-chamber1 ,f1 that contains at its upper part a small aperture1 b1 that remains always open1 and1 at its lower part1 a copper screw-plug1 d1 and a galvanized hook1 ,h4 ,in the interior of this chamber there is arranged a small leaden siphon1 a b c1 whose longer leg1 a1 passes through the bottom1 where it is soldered1 and whose shorter one1 c1 ends in close proximity to the bottom4 ,finally1 a galvanized iron chain1 ,g ,h1 fixed at ,g to the bottom of the reservoir1 and provided with a weight1 ,p1 of galvanized iron1 is hooked at ,h to the siphon and allows it to rise more or less1 according as it is given a greater or less length4 ,from what precedes1 it will be seen that the outlet is entirely closed1 so that1 in order that the water may escape1 it must pass into the pipe in the direction1 ,e ,d ,b ,a ,c4 ,this granted1 let us see how the apparatus works3 ,in measure as the water rises in the reservoir1 the siphon gradually loses weight1 and its extremity1 ,b ,d ,h1 is finally lifted by the thrust1 so that the entire affair revolves upon the studs1 ,k1 until the chain becomes taut4 ,the apparatus then ceases to rise2 but the water1 ever continuing to rise1 finally reaches the apex1 b1 of the smaller siphon1 and1 through it1 enters the air chamber and fills it4 ,the equilibrium being thus broken1 the siphon descends to the bottom1 becomes primed1 and empties the reservoir4 ,when the level of the water1 in descending1 is at the height of the small siphon1 a b c1 this latter1 which is also primed1 empties the chamber1 ,f1 in turn1 so that1 at the moment the large siphon loses its priming1 the entire apparatus is in the same state that it was at first4 ,in short1 when the water enters the reservoir1 the siphon1 movable upon its base1 rises to the height at which it is desired that the flow shall take place4 ,being arrested at this point by the chain1 it becomes primed1 and sinks1 and the water escapes4 ,when the water is exhausted1 the siphon rises anew in order to again sink2 and this goes on as long as the period of irrigation lasts4 ,this apparatus1 which is simple in its operation1 and not very costly1 is being employed with success for irrigating several meadows in the upper basin of the ,allier4--,le ,genie ,civil4 99 99 99 99 99 ,,assay ,,of ,,earthenware ,,glaze4 ,lead oxide melted or incompletely vitrified is still in common use in the manufacture of inferior earthenware1 and sometimes leads to serious results4 ,to detect lead in a glaze1 ,m4 ,herbelin moistens a slip of white linen or cotton1 free from starch1 with nitric acid at #aj per cent4 and rubs it for ten to fifteen seconds on the side of the utensil under examination1 and then deposits a drop of a solution of potassium iodide1 at #e per cent4 on the part which has been in contact4 ,a lead glaze simply fused gives a very highly colored yellow spot of potassium iodide2 a lead glaze incompletely vitrified gives spots the more decided1 the less perfect the vitrification2 and a glaze of good quality gives no sensible color at all4--,m4 ,herbelin4 99 99 99 99 99 ,,on ,,the ,,electrical ,,furnace ,,and ,,the ,,reduction ,,of ,,the ,,oxides ,,of ,,boron1 ,,silicon1 ,,aluminum1 ,,and ,,other ,,metals ,,by ,,carbon4#a ,footnote #a3 ,read at the recent meeting of the ,american ,association1 ,ann ,arbor1 ,mich4 ,by ,,eugene ,h4 ,,cowles1 ,,alfred ,h4 ,,cowles1 ,,and ,,charles ,f4 ,,mabery4 ,the application of electricity to metallurgical processes has hitherto been confined to the reduction of metals from solutions1 and few attempts have been made to effect dry reductions by means of an electric current4 ,sir ,w4 ,siemens attempted to utilize the intense heat of an electric arc for this purpose1 but accomplished little beyond fusing several pounds of steel4 ,a short time since1 ,eugene ,h4 ,cowles and ,alfred ,h4 ,cowles of ,cleveland conceived the idea of obtaining a continuous high temperature on an extended scale by introducing into the path of an electric current some material that would afford the requisite resistance1 thereby producing a corresponding increase in the temperature4 ,after numerous experiments that need not be described in detail1 coarsely pulverized carbon was selected as the best means for maintaining a variable resistance and at the same time as the most available substance for the reduction of oxides4 ,when this material1 mixed with the oxide to be reduced1 was made a part of the electric circuit in a fire clay retort1 and submitted to the action of a current from a powerful dynamo machine1 not only was the oxide reduced1 but the temperature increased to such an extent that the whole interior of the retort fused completely4 ,in other experiments lumps of lime1 sand1 and corundum were fused1 with indications of a reduction of the corresponding metal2 on cooling1 the lime formed large1 well-defined crystals1 the corundum beautiful red1 green1 and blue hexagonal crystals4 ,following up these results with the assistance of ,charles ,f4 ,mabery1 professor of chemistry in the ,case ,school of ,applied ,science1 who became interested at this stage of the experiments1 it was soon found that the intense heat thus produced could be utilized for the reduction of oxides in large quantities1 and experiments were next tried on a large scale with a current from two dynamos driven by an equivalent of fifty horse power4 ,for the protection of the walls of the furnace1 which were made of fire brick1 a mixture of the ore and coarsely pulverized gas carbon was made a central core1 and it was surrounded on the sides and bottom by fine charcoal1 the current following the lesser resistance of the central core from carbon electrodes which were inserted at the ends of the furnace in contact with the core4 ,in order to protect the machines from the variable resistance within the furnace1 a resistance box consisting of a coil of ,german silver wire placed in a large tank of water was introduced into the main circuit1 and a ,brush ammeter was also attached by means of a shunt circuit1 to indicate the quantity of current that was being absorbed in the furnace4 ,the latter was charged by first filling it with charcoal1 making a trough in the center1 and filling this central space with the ore mixture1 which was covered with a layer of coarse charcoal4 ,the furnace was closed at the top with fire brick slabs containing two or three holes for the escape of the gaseous products of the reduction1 and the entire furnace made air-tight by luting with fire clay4 ,within a few minutes after starting the dynamo1 a stream of carbonic oxide issued through the openings1 burning usually with a flame eighteen inches in height4 ,the time required for complete reduction was ordinarily about an hour4 ,the furnace at present in use is charged in substantially the same manner1 and the current is supplied by a ,brush machine of variable electromotive force driven by an equivalent of forty horse power4 ,a ,brush machine capable of utilizing #abe horse power1 or two and one-half times as large as any hitherto constructed by the ,brush ,electric ,company1 is being made for the ,cowles ,electric ,smelting and ,aluminum ,company1 and this machine will soon be in operation4 ,experiments already made so that aluminum1 silicon1 boron1 manganese1 magnesium1 sodium and potassium can be reduced from their oxides with ease4 ,in fact1 there is no oxide that can withstand temperatures attainable in this electrical furnace4 ,charcoal is changed to graphite4 ,does this indicate fusion or solution of carbon8 ,as to what can be accomplished by converting enormous electrical energy into heat within a limited space1 it can only be said that it opens the way into an extensive field for both pure and applied chemistry4 ,it is not difficult to conceive of temperatures limited only by the capability of carbon to resist fusion4 ,the results to be obtained with the large ,brush machine above mentioned will be of some importance in this direction4 ,since the cost of the motive power is the chief expense in accomplishing reductions by this method1 its commercial success is closely connected with the cheapest form of power to be obtained4 ,realizing the importance of this point1 the ,cowles ,electric ,smelting and ,aluminum ,company has purchased an extensive and reliable water power1 and works are soon to be erected for the utilization of #a1bjj horse power4 ,an important feature in the use of these furnaces1 from a commercial standpoint1 is the slight technical skill required in their manipulation4 ,the four furnaces in operation in the experimental laboratory at ,cleveland are in charge of two young men twenty years of age1 who1 six months ago1 knew absolutely nothing of electricity4 ,the products at present manufactured are the various grades of aluminum bronze made from a rich furnace product that is obtained by adding copper to the charge of ore1 silicon bronze prepared in the same manner1 and aluminum silver1 an alloy of aluminum with several other metals4 ,a boron bronze may be prepared by the reduction of boracic acid in contact with copper4 ,as commercial results may be mentioned the production in the experimental laboratory1 which averages fifty pounds of #aj per cent4 aluminum bronze daily1 and it can be supplied to the trade in large quantities at prices based on #e per pound for the aluminum contained1 the lowest market quotation of this metal being at present #ae per pound4 ,silicon bronze can be furnished at prices far below those of the ,french manufacturers4 ,the alloys which the metals obtained by the methods above described form with copper have been made the subject of careful study4 ,an alloy containing #aj per cent4 of aluminum and #ij per cent4 of copper forms the so-called aluminum bronze with a fine golden color1 which it retains for a long time4 ,the tensile strength of this alloy is usually given as #ajj1jjj pounds to the square inch2 but castings of our ten per cent4 bronze have stood a strain of #aji1jjj pounds4 ,it is a very hard1 tough alloy1 with a capacity to withstand wear far in excess of any other alloy in use4 ,all grades of aluminum bronze make fine castings1 taking very exact impressions1 and there is no loss in remelting1 as in the case of alloys containing zinc4 ,the #e per cent4 aluminum alloy is a close approximation in color to #ah carat gold1 and does not tarnish readily4 ,its tensile strength in the form of castings is equivalent to a strain of #fh1jjj pounds to the square inch4 ,an alloy containing #b or #c per cent4 aluminum is stronger than brass1 possesses greater permanency of color1 and would make an excellent substitute for that metal4 ,when the percentage of aluminum reaches #ac1 an exceedingly hard1 brittle alloy of a reddish color is obtained1 and higher percentages increase the brittleness1 and the color becomes grayish-black4 ,above #be per cent4 the strength again increases4 ,the effect of silicon in small proportions upon copper is to greatly increase its tensile strength4 ,when more than #e per cent4 is present1 the product is exceedingly brittle and grayish-black in color4 ,it is probable that silicon acts to a certain extent as a fluxing material upon the oxides present in the copper1 thereby making the metal more homogeneous4 ,on account of its superior strength and high conductivity for electrical currents1 silicon bronze is the best material known for telegraph and telephone wire4 ,the element boron seems to have almost as marked an effect upon copper as carbon does upon iron4 ,a small percentage in copper increases its strength to #ej1jjj or #fj1jjj pounds per square inch without diminishing to any large extent its conductivity4 ,aluminum increases very considerably the strength of all metals with which it is alloyed4 ,an alloy of copper and nickel containing a small percentage of aluminum1 called ,hercules metal1 withstood a strain of #aje1jjj pounds1 and broke without elongation4 ,another grade of this metal broke under a strain of #aaa1jjj pounds1 with an elongation equivalent to #cc per cent4 ,it must be remembered that these tests were all made upon castings of the alloys4 ,the strength of common brass is doubled by the addition of #b or #c per cent4 of aluminum4 ,alloys of aluminum and iron are obtained without difficulty2 one product was analyzed1 containing #dj per cent4 of aluminum4 ,in the furnace iron does not seem to be absorbed readily by the reduced aluminum when copper is present2 but in one experiment a mixture composed of old files1 #fj per cent42 nickel1 #e per cent42 and of #aj per cent4 aluminum bronze #ce per cent41 was melted together1 and it gave a malleable product that stood a strain of #fi1jjj pounds4 ,when the reduction of aluminic oxide by carbon is conducted without the addition of copper1 a brittle product is obtained that behaves in many respects like pig iron as it comes from the blast furnace4 ,the same product is formed in considerable quantities1 even when copper is present1 and frequently the copper alloy is found embedded in it4 ,graphite is always found associated with it1 even when charcoal is the reducing material1 and analysis invariably shows a very high percentage of metallic aluminum4 ,this extremely interesting substance is at present under examination4 99 99 99 99 99 ,,the ,,cowles ,,electric ,,smelting ,,process4 ,the use of electricity in the reduction of metals from their ores is extending so rapidly1 and the methods of its generation and application have been so greatly improved within a few years1 that the possibility of its becoming the chief agent in the metallurgy of the future may now be admitted1 even in cases where the present cost of treatment is too high to be commercially advantageous4 ,the refining of copper and the separation of copper1 gold1 and silver by electrolysis have thus far attracted the greatest amount of attention1 but a commercial success has also been achieved in the dry reduction by electricity of some of the more valuable metals by the ,cowles ,electric ,smelting and ,aluminum ,company1 of ,cleveland1 ,ohio4 ,both this method of manufacture and the qualities of the products are so interesting and important that it is with pleasure we call attention to them as steps toward that large and cheap production of aluminum that the abundance of its ores and the importance of its physical properties have for several years made the unattained goal of many skillful metallurgists4 ,the ,messrs4 ,cowles have succeeded in greatly reducing the market value of aluminum and its alloys1 and thereby vastly extending its uses1 and they are now by far the largest producers in the world of these important products4 ,as described in their patents1 the ,cowles process consists essentially in the use for metallurgical purposes of a body of granular material of high resistance or low conductivity interposed within the circuit in such a manner as to form a continuous and unbroken part of the same1 which granular body1 by reason of its resistance1 is made incandescent1 and generates all the heat required4 ,the ore or light material to be reduced--as1 for example1 the hydrated oxide of aluminum1 alum1 chloride of sodium1 oxide of calcium1 or sulphate of strontium--is usually mixed with the body of granular resistance material1 and is thus brought directly in contact with the heat at the points of generation1 at the same time the heat is distributed through the mass of granular material1 being generated by the resistance of all the granules1 and is not localized at one point or along a single line4 ,the material best adapted for this purpose is electric light carbon1 as it possesses the necessary amount of electrical resistance1 and is capable of enduring any known degree of heat when protected from oxygen without disintegrating or fusing2 but crystalline silicon or other equivalent of carbon can be employed for the same purpose4 ,this is pulverized or granulated1 the degree of granulation depending upon the size of the furnace4 ,coarse granulated carbon works better than finely pulverized carbon1 and gives more even results4 ,the electrical energy is more evenly distributed1 and the current can not so readily form a path of highest temperature1 and consequently of least resistance through the mass along which the entire current or the bulk of the current can pass4 ,the operation must necessarily be conducted within an air-tight chamber or in a non-oxidizing atmosphere1 as otherwise the carbon will be consumed and act as fuel4 ,the carbon acts as a deoxidizing agent for the ore or metalliferous material treated1 and to this extent it is consumed1 but otherwise than from this cause1 it remains unimpaired4 ,fig4 ,i4 of the accompanying drawings is a vertical longitudinal section through a retort designed for the reduction of zinc ore1 according to this process1 and ,fig4 ,,ii4 is a front elevation of the same4 ,fig4 ,,iii4 is a perspective view of a furnace adapted to withstand a very high temperature1 and ,figs4 ,,iv4 and ,v4 are respectively longitudinal and transverse sections of the same4 ,illustration3 ,,the ,,cowles ,,electric ,,smelting ,,process4 ,this retort consists of a cylinder1 ,a1 made of silica or other non-conducting material1 suitably embedded in a body1 ,b1 of powdered charcoal1 mineral wool1 or of some other material which is not a good conductor of heat4 ,the rear end of the retort-cylinder is closed by means of a carbon plate1 ,c1 which plate forms the positive electrode1 and with this plate the positive wire of the electric circuit is connected4 ,the outer end of the retort is closed by means of an inverted graphite crucible1 ,d1 to which the negative wire of the electric circuit is attached4 ,the graphite crucible serves as a plug for closing the end of the retort4 ,it also forms a condensing chamber for the zinc fumes1 and it also constitutes the negative electrode4 ,the term electrode is used in this case as designating the terminals of the circuit proper1 or that portion of it which acts simply as an electrical conductor1 and not with the intention of indicating the ends of a line between which there is no circuit connection4 ,the circuit between the electrodes1 so called1 is continuous1 being established by means of and through the body of broken carbon contained in the retort1 ,a4 ,there is no deposit made on either plate of the decomposed constituents of the material reduced4 ,the mouth of the crucible is closed with a luting of clay1 or otherwise1 and the opening1 d1 made in the upper side of the crucible1 near its extremity1 comes entirely within the retort1 and forms a passage for the zinc fumes from the retort chamber into the condensing chamber4 ,the pipe1 ,e1 serves as a vent for the condensing chamber4 ,the zinc ore is mixed with pulverized or granular carbon1 and the retort charged nearly full through the front end with the mixture1 the plug1 ,d1 being removed for this purpose4 ,a small space is left at the top1 as shown4 ,after the plug has been inserted and the joint properly luted1 the electric circuit is closed and the current allowed to pass through the retort1 traversing its entire length through the body of mixed ore and carbon4 ,the carbon constituents of the mass become incandescent1 generating a very high degree of heat1 and being in direct contact with the ore1 the latter is rapidly and effectually reduced and distilled4 ,the heat evolved reduces the ore and distills the zinc1 and the zinc fumes are condensed in the condensing chamber1 precisely as in the present method of zinc making1 with this important exception that1 aside from the reaction produced by heating carbon in the presence of zinc oxide1 the electric current1 in passing through the zinc oxide1 has a decomposing and disintegrating action upon it1 not unlike the effect produced by an electric current in a solution4 ,this action accelerates the reduction1 and promotes economy in the process4 ,another form of furnace is illustrated by ,fig4 ,,iii41 which is a perspective view of a furnace adapted for the reduction of ores and salts of non-volatile metals and similar chemical compounds4 ,figs4 ,,iv4 and ,v4 are longitudinal and transverse sections1 respectively1 through the same1 illustrating the manner of packing and charging the furnace4 ,the walls and floors ,l ,l'1 of the furnace are made of fire bricks1 and do not necessarily have to be very thick or strong1 the heat to which they are subjected not being excessive4 ,the carbon plates are smaller than the cross section of the box1 as shown1 and the spaces between them and the end walls are packed with fine charcoal4 ,the furnace is covered with a removable slab of fireclay1 ,n1 which is provided with one or more vents1 n1 for the escaping gases4 ,the space between the carbon plates constitutes the working part of the furnace4 ,this is lined on the bottom and sides with a packing of fine charcoal1 ,o1 or such other material as is both a poor conductor of heat and electricity--as1 for example1 in some cases1 silica or pulverized corundum or well-burned lime--and the charge1 ,p1 of ore and broken1 granular1 or pulverized carbon occupies the center of the box1 extending between the carbon plates4 ,a layer of granular charcoal1 ,o'1 also covers the charge on top4 ,the protection afforded by the charcoal jacket1 as regards the heat1 is so complete1 that with the covering-slab removed1 the hand can be held within a few inches of the exposed charcoal jacket2 but with the top covering of charcoal also removed and the core exposed1 the hand cannot be held within several feet4 ,the charcoal packing behind the carbon plates is required to confine the heat and to protect them from combustion4 ,with this furnace1 aluminum can be reduced directly from its ores2 and chemical compounds from corundum1 cryolite1 clay1 etc41 and silicon1 boron1 calcium1 manganese1 magnesium1 and other metals are in like manner obtained from their ores and compounds4 ,the reduction of ores according to this process can be practiced1 if circumstances require it1 without any built furnace4 ,at present1 the ,cowles company is engaged mostly in the producing of aluminum bronze and aluminum silver and silicon bronze4 ,the plant1 were it run to its full capacity1 is capable of turning out eighty pounds of aluminum bronze1 containing #aj per cent4 of aluminum daily2 or1 were it to run upon silicon bronze1 could turn out one hundred and twenty pounds of that per day1 or1 we believe1 more aluminum bronze daily than can be produced by all other plants in the world combined4 ,this production1 however1 is but that of the experimental laboratory1 and arrangements are making to turn out a ton of bronze daily1 and the works have an ultimate capacity of from eight to ten thousand horse power4 ,the energy consumed by the reduction of the ore is almost entirely electrical1 only enough carbon being used to unite with the oxygen of the ore to carry it out of the furnace in the form of the carbon monoxide1 the aluminum remaining behind4 ,consequently1 the plant necessary to produce aluminum on a large scale involves a large number of the most powerful dynamos4 ,these are to be driven by water-power or natural gas and marine engines of great capacity4 ,the retail price of standard #aj per cent4 aluminum bronze is #a per pound avoirdupois1 which means less than #i per pound for aluminum1 the lowest price at which it has ever been sold1 yet the ,cowles company has laid a proposition before the ,government to furnish this same bronze in large quantities at very much lower prices than this4 ,the ,hercules alloy1 castings of which will stand over #ajj1jjj pounds to the square inch tensile strain1 sells at #ge c4 a pound1 and is also offered the ,government or other large consumers at a heavy discount4 ,the alloys are guaranteed to contain exactly what is advertised2 they are standardized into #aj per cent41 #g4e per cent41 #e per cent4 and #b4e per cent4 aluminum bronze before shipment4 ,the current available at the ,cowles company's works was1 until recently1 #ccj amperes1 driven by an electromotive force of #aaj volts and supplied by two ,edison dynamos2 but the company has now added a large ,brush machine that has a current of #efj amperes and #eb volts electromotive force4 ,we shall1 on another occasion1 give some particulars of experiments in the reduction of refractory ores by the process4--,eng4 and ,mining ,jour4 99 99 99 99 99 ,,optical ,,telegraphy4#a ,footnote #a3 ,continued from page #hjid4 ,,cryptography4--,,preservation ,,of ,,telegrams4 ,optical telegraphy1 by reason of its very principle1 presents both the advantage and inconvenience of leaving no automatic trace of the correspondence that it transmits4 ,the advantage is very evident in cases in which an optical station falls into the hands of the enemy2 on the other hand1 the inconvenience is shown in cases where a badly transmitted or badly collated telegram allows an ambiguity to stand subject to dispute4 ,moreover1 in case of warfare between civilized nations that have all the resources of science at their disposal1 there may be reason to fear lest one of the enemy's optical stations substitute itself for the corresponding station1 and take advantage of the situation to throw confusion into the orders transmitted4 ,the remedy for this appears to reside in the use of cryptography and in the exchange1 at various intervals1 of certain words that have been agreed upon beforehand1 and that the enemy is ignorant of4 ,as for the automatic preservation of telegrams1 the problem has not been satisfactorily solved4 ,it has been proposed to connect the key of the manipulator of the optical apparatus with the manipulator of an ordinary ,morse apparatus1 thus permitting the telegram to be preserved upon a band of paper4 ,it is unnecessary to say that the space occupied by a dispatch thus transmitted would be considerable2 but this is not what has stopped innovators4 ,the principal objection resides in the increase in muscular work imposed by this arrangement upon the telegrapher4 ,obliged to keep his eye fixed intently at the receiving telescope1 while at the same time maneuvering the manipulator and spelling aloud the words that he is receiving1 the operator should have a very sensitive manipulator at his disposal1 and not be submitted to mental or physical overtaxation4 ,so the apparatus that have been devised have not met with much success4 ,two ,french officers1 working independently1 have hit upon the same idea of receiving the indications transmitted by the vibration of the luminous fascicle directly upon their travel4 ,the method consists in the use of that peculiar property of selenium of becoming a good conductor under the action of a luminous ray1 while in darkness it totally prevents the passage of the electric current4 ,such modification of the physical properties of selenium1 moreover1 occurs without the perceptible development of any mechanical work4 ,if1 then1 in the line of travel of the luminous fascicle emitted by the optical apparatus1 or in a portion of such fascicle1 we interpose a fragment of selenium connected with the two poles of a local pile1 it is easy to see that the current from the latter will be opened or closed according as the luminous ray from the apparatus will or will not strike the selenium1 and that the length of time during which the current passes will depend upon the length of the luminous attacks4 ,a ,morse apparatus interposed in this annexed circuit will therefore give an automatic inscription of the correspondence exchanged4 ,such is the principle4 ,but1 practically1 very great difficulties present themselves1 these being connected with the rapid weakening of the electric properties of the selenium1 and with the necessity of having recourse to infinitely small mechanical actions only4 ,the problem is nevertheless before us1 and it is to be hoped that the perseverance of the scientists who are at work upon it will some day succeed in solving it4 ,finally1 we may call attention to the attempts made to receive the luminous impression upon a band prepared with gelatino-bromide of silver4 ,in practice this band would unwind uniformly at the focus of the receiving telescope1 which would be placed in a box1 forming a camera obscura4 ,the velocity of this band prepared for photographing the signals would be regulated by clockwork4 ,the experiments that have been made have not given results that are absolutely satisfactory1 by reason of the length of the signals received and the mechanical complication of the device4 ,,optical ,,telegraphy ,,by ,,means ,,of ,,projectors4 ,illustration3 ,,fig4 #bc4 ,the projectors employed for lighting to a distance the surroundings of a stronghold or of a ship have likewise been applied in optical telegraphy4 ,for this purpose ,messrs4 ,sautter1 ,lemonnier ,co4 have added to their usual projecting apparatus some peculiar arrangements that permit of occultations of the luminous focus at proper intervals4 ,figs4 #ba and #bb show the arrangement of the apparatus1 the principle of which is as follows3 ,when the axis of the projector points toward the clouds1 and in the direction occupied by a corresponding station1 the occultations of the luminous source placed in the focus of the apparatus produce upon the clouds1 which act as a screen1 an alternate series of flashes and extinctions4 ,it is therefore possible with this arrangement1 and by the use of the ,morse alphabet1 to establish an optical communication at a distance4 ,the use of this projector 7the principal inconvenience of which is that it requires a clouded sky7 even permits two observers who are hidden from each other by the nature of the ground to easily communicate at a distance of #cf or #dh miles4 ,,use ,,of ,,the ,,projector ,,in ,,optical ,,telegraphy4 ,illustration3 ,,figs4 #ba ,,and #bb4--;,,front ,,view ,,and ,,longitudinal ,,section ,,of ,,the ,,mangin ,,projector4 7,scale #a_/ae74 ,a4 ,elliptical mirror4 ,b4 ,arm of the same4 ,c4 ,nut for fixing the mirror4 ,d4 ,support of the mirror4 ,e4 ,occultator4 ,f4 ,support for same4 ,g4 ,lever for maneuvering the occultator4 ,i4 ,support of the occultator rod4 ,j4 ,screw for fixing the mirror support4 ,k4 ,screw for fixing the support of the occultator rod4 ,l4 ,screw for fixing the occultator support4 ,the apparatus shown in ,figs4 #ba and #bb permits of signaling in three ways3 #a4 ,upon the ,clouds4--,in this case the mirror1 ,a1 is removed1 and the projector inclined above the horizon in such a way as to illuminate the clouds to as great a distance as possible4 ,a maneuver of the occultator1 ,e1 between the lamp and the mirror arrests the luminous rays of the source1 or allows them to pass1 and thus produces upon the clouds the dots and dashes of the conventional alphabet4 #b4 ,isolated ,communication by ,luminous ,fascicles4--,when it is desired to correspond to a short distance of #b or #c miles1 and establish a communication between two isolated posts1 the mirror1 ,a1 is put in place upon its support1 ,b4 ,the luminous fascicle emanating from the source reflected by the mirror is thrown vertically4 ,by revolving the mirror #ij around its horizontal axis the fascicle becomes horizontal1 and may thus be thrown in a given direction at unequal intervals and during irregular times1 and furnish conventional signs4 #c4 ,night ,communication upon the ,entire ,horizon4--,when we wish to correspond at a short distance1 say two miles1 and make signals visible from the entire horizon1 the mirror1 ,a1 is put in place1 so that it shall reflect the luminous fascicle vertically4 ,the fascicle1 at a distance of about fifty feet1 meets a white balloon which it renders visible from every point in the horizon4 ,the maneuver of the occultator brings the balloon out of darkness or plunges it thereinto again1 and thus produces the signs necessary for aerial communication4 ,illustration3 ,,fig4 #bd4 ,these ingenious arrangements1 which depend upon the state of the atmosphere1 do not appear to have been imitated outside of the navy4 ,,capt4 ,,gaumet',s ,,optical ,,telegraph4 ,the system of optical communication proposed by ,capt4 ,gaumet1 and which he names the ,telelogue1 is based upon the visibility of colored or luminous objects1 and upon the possibility of piercing the opaque curtain formed by the atmosphere between the observer's eye and a signal1 by utilizing the difference in brightness that exists between such objects and the atmosphere4 ,it is a question1 then1 of giving such difference in intensity its maximum of brightness4 ,to do this1 ,capt4 ,gaumet proposes to employ silvered signals upon a black background4 ,he uses the simple letters of the alphabet1 but changes their value4 ,his apparatus has the form of a large album glued at the back to a sloping desk4 ,each silvered letter1 glued to a piece of black cloth1 is seen in relief upon the open register4 ,a sort of index along the side1 as in commercial blank-books1 permits of quickly finding any letter at will4 ,such is the manipulator of the apparatus4 ,the receiver consists of a spy-glass affixed to the board that carries the register4 ,for a range of two and a half miles1 the complete apparatus1 with a #abaf inch manipulator and telescope1 weighs but four and a half pounds4 ,for double this range1 with a #bjbh inch manipulator and telescope1 the total weight is thirteen pounds4 ,the larger apparatus1 according to the inventor1 have a range of seven miles4 ,for night work the manipulator is lighted either by one lamp1 or by two lamps with reflector1 placed laterally against it4 ,this apparatus1 although well known1 and having been publicly experimented with1 has not1 to our knowledge1 been applied practically4 ,from a military standpoint1 its short range will evidently not permit it to compete with optical telegraphic apparatus1 properly so called4 ,perhaps it might rather be of service for private communications between localities not very far apart1 since it costs but little and is easily operated4 ,,optical ,,signaling ,,between ,,bodies ,,of ,,troops4 ,optical communications by signals1 during day and night1 with experienced men1 may1 in the absence of telephones1 telegraphs1 and messengers1 render important service when the distance involved is greater than two thousand feet4 ,this mode of correspondence is based upon the use of the ,morse alphabet4 ,the signals are divided into night and day ones4 ,the day signals are made with small flags4 ,when these are wanting1 sheets of white cardboard may be used4 ,the night signals are made with a lantern provided with a support1 which may be fixed to a wall or upon a bayonet4 ,in day signaling1 the dashes of the ,morse alphabet are formed by means of two flags 7,fig4 #bc7 held simultaneously at arm's length by the signaler4 ,the dots are formed with a single flag held in the right hand 7,fig4 #bd74 ,in this way it is possible1 by extremely simple combinations1 to establish a correspondence1 and produce any conventional signal4 ,by means of relay stations1 the signals may be transmitted from one to another to a great distance4 ,in signaling with the lantern1 long and short interruptions of the luminous source are produced by means of a screen4 ,,optical ,,telegraphy ,,by ,,luminous ,,balloons4 ,various interesting experiments have been made with a view to utilizing luminous captive balloons for optical communications4 ,as we have already seen1 this maybe effected by using opaque balloons1 and throwing upon them at unequal intervals a luminous fascicle by means of a projector4 ,as for using a luminous source placed in the car of a balloon1 that cannot be thought of in the present state of aeronautic science2 the continual rotation of the balloon around its axis would render the projection and reception of the signals in a given direction impossible4 ,,optical ,,telegraphy ,,in ,,the ,,marine4 ,for communicating optically from ship to ship during the day1 the marine uses flags of different forms and colors1 and flames4 ,between ships and the land there are used what are called semaphore signals1 which are made by means of a mast provided with three arms and a disk placed at the upper part4 ,the combinations of signs thus obtained1 which are analogous in principle to those of the ,chappe telegraph1 permit of satisfactorily communicating to a distance4 ,on board ship1 hand signals are used like those employed by the army for communicating between bodies of troops4 ,for night communications the marine employs lights corresponding to the day flags1 as well as rockets1 and luminous rays projected by means of reflectors and intercepted by screens4 ,in conclusion1 it may be said that optical telegraphy1 which has only within a few years emerged from the domain of theory to enter that of practice1 has taken a remarkable stride in the military art and in science4 ,it is due to its processes that ,col4 ,perrier has in recent years been enabled to carry out certain geodesic work that would have formerly been regarded as impracticable1 notably the prolongation of the arc of the meridian between ,france and ,spain4 ,very recently1 an optical communication established between ,mauritius and ,reunion islands1 to a distance of #abi miles1 with #bd inch apparatus1 proved that1 in certain cases1 the costly laying of a submarine cable may be replaced by the direct emission of a luminous ray4 99 99 99 99 99 ,a ,,new ,,style ,,of ,,submarine ,,telegraph4 ,mr4 ,f4 ,von ,faund-,szyll has devised an original system of submarine telegraph1 which is based upon the well known property that selenium exhibits of modifying its resistance under the influence of luminous rays1 and which he styles the ,selen-,differenzialrecorder4 ,contrary to what is found in the other systems hitherto employed1 the ,faund-,szyll system utilizes the cable current merely for starting the receiving apparatus1 which are operated by means of strong local batteries4 ,the result is that the mechanical work that devolves upon the line current1 which is1 as well known1 very weak1 is exceedingly reduced4 ,the system consists of two essential parts3 7#a7 ,the receiver1 properly so called4 7#b7 ,the relay as well as the registering apparatus or differenzialrecorder4 ,the receiver consists of a closed box1 ,k1 in the interior of which there is a very intense source of light whose rays escape by passing through apertures1 a a'1 in the front part 7,fig4 #a74 ,as a source of light1 there may be conveniently employed an incandescent lamp1 g1 capable of giving an intense light1 and arranged 7as shown in ,fig4 #b7 behind the side that contains the slits1 a a'4 ,the starting apparatus consists of a small galvanometric helix1 r1 analogous to ,thomson's siphon recorder1 which is suspended from a cocoon fiber and capable of moving in an extremely powerful magnetic field1 ,n ,s4 ,this helix carries1 as may be seen in ,figs4 #a1 #c and #d1 a prolongation1 v1 at its lower end whose form is that of a prism1 and which is arranged in front of the partition of the box1 ,k1 in such a way that it exactly covers the two slits1 a and a when the bobbin is at rest1 and in this case prevents the luminous rays of the lamp1 g1 from escaping from the box4 ,but1 as soon as the current sent through the cable reaches the spirals of the bobbin1 through the conductors1 y y'1 the sum of the elementary electrodynamic actions that arise causes the helix to revolve to the right or left1 according to the polarity of the current1 while at the same time the helix slightly approaches one or the other of the poles of the magnet4 ,the prolongation1 v1 of the helix1 being firmly united with the latter1 follows it in its motion1 and has the effect of permitting the luminous rays to escape through one or the other of the slits1 a a'1 so that the freeing of the luminous fascicle1 if such an expression is allowable1 is effected4 ,illustration3 ,,fig4 #a4 ,in order to prevent oscillations1 which could not fail to occur after each emission of a current 7so that the helix1 instead of returning to a position of equilibrium and stopping there1 would go beyond it and alternately uncover the slits1 a a'71 the apparatus is provided with a liquid deadener4 ,to this end1 the prolongation1 v1 carries a piece1 o1 which dips into a cup containing a mixture of glycerine and water4 ,we shall now describe the differenzialrecorder4 ,opposite the two slits1 a and a'1 there are two powerful converging lenses1 l and l'1 whose foci coincide with two sorts of selenium plate rheostat1 z and z'4 ,the result of this arrangement is that as soon as one of the slits1 as a consequence of the displacement of the helix1 r1 allows a luminous fascicle to escape1 this latter falls upon the corresponding lens1 which concentrates it and sends it to the selenium plates just mentioned4 ,under the influence of the luminous rays1 the resistance that the selenium offers to the passage of an electric current instantly changes4 ,at ,m and ,m' are placed two horseshoe magnets whose poles are provided with pieces of soft iron that serve as cores to exceedingly fine wire bobbins1 d4 ,these polarized pieces are arranged in the shape of a ,st4 ,andrew's cross1 and in such a way that the poles of the same name occupy the two extremities of the same arm of the cross1 an arrangement very clearly shown in ,fig4 #b4 ,illustration3 ,,fig4 #b4 ,between the poles of the magnets1 ,m and ,m'1 there is a permanent magnet1 ,a1 movable around a vertical axis1 i4 ,four spiral springs1 f1 whose tension may be regulated1 permit of centering this latter piece in such a way that when the current is traversing the spirals of the polar bobbins it is equally distant from the four poles1 n1 s1 s'1 and n'4 ,under such circumstances it is evident that a difference in the power of attraction of these four poles1 however feeble it be1 will result in moving the magnet1 ,a1 in one direction or the other around its axis4 ,the energy and extent of such motion may1 moreover1 be magnified by properly acting upon the four regulating springs4 ,the bobbins of the magnet1 ,m1 are mounted in series with the selenium plates1 z1 the local battery1 ,b1 and a resistance box1 ,w4 ,those of the magnet1 ,m'1 are in series with z'1 ,b'1 and ,w'4 ,the local batteries1 ,b and ,b'1 are composed of quite a large number of elements4 ,the current from the battery1 ,b1 traverses the selenium plates and the bobbins of the magnet1 ,m1 and returns to ,b through the rheostat1 ,w2 and the same occurs with the current from ,b'4 ,the two currents1 then1 are absolutely independent of one another4 ,from this description it is very easy to see how the system works4 ,let us suppose1 in fact1 that the current which is traversing the spirals of the helix1 r1 has a direction such that the helix in its movement approaches the pole1 ,s2 then the prolongation1 v1 will uncover the slit1 a1 which1 along with a'1 had up to this moment been closed1 and a luminous fascicle escaping through a will strike the lens1 l'1 and from thence converge upon the selenium plates1 z'4 ,this is all the duty that the line current has to perform4 ,the luminous rays1 in falling upon the selenium plates1 z'1 modify the resistance that these offered to the passage of the current produced by the battery1 ,b'4 ,as this resistance diminishes1 the intensity of the current in the circuit supplied by the battery1 ,b'1 increases1 the attractive action of the polar pieces of the magnet1 ,m'1 diminishes1 the equilibrium is destroyed1 and the piece1 ,a1 revolves around the axis1 i4 ,if the polarity of the line current were different1 the same succession of phenomena would occur1 save that the direction of ,a's rotation would be contrary4 ,as for the rheostats1 ,w ,w'1 their object is to correct variations in the selenium's resistance and to balance the resistances of the two corresponding circuits4 ,the magnet1 ,a1 will be combined with a registering apparatus so as to directly or indirectly actuate the printing lever4 ,the entire first part of this apparatus1 which is very sensitive1 may be easily protected from all external influence by placing it in a box1 and1 if need be1 in a room distant from the one in which the employes work4 ,illustration3 ,,figs4 #c ,,and #d4 ,the differenzialrecorder alone has to be in the work room4 ,as may be seen1 the system is not wanting in originality4 ,experience alone will permit of pronouncing upon the question as to whether it is as practical as ingenious4--,la ,lumiere ,electrique4 99 99 99 99 99 ,a ,,new ,,circuit ,,cutter4 ,messrs4 ,thomson ,bottomley have recently invented a peculiar circuit cutter based upon the use of a metal whose melting point is exceedingly low4 ,recourse is had to this process for breaking the current within as short a time as possible4 ,in this new device the ends of the conductors are soldered together with the metal in question at one or several points of the circuit4 ,the metal employed is silver or copper of very great conductivity1 seeing that the increase of temperature in a conductor1 due to a sudden increase of the current1 is inversely proportional to the product of the electric resistance by the specific heat of the conductor2 that these metals are best adapted for giving constant and definite results2 and that the contacts are better than with lead or the other metals of low melting point which are frequently employed in circuit cutters4 ,illustration3 ,,fig4 #a4 ,fig4 #a represents one form of the new device4 ,here1 a is the copper or silver wire1 and b is a soldering made with a very fusible metal and securing a continuity of the circuit4 ,each extremity of the wire1 a1 is connected with a heavy ring1 c1 of copper or other good conducting metal4 ,the hook1 d1 with which the upper ring1 c1 is in contact1 communicates metallically with one of the extremities of the conductor at the place where the latter is interrupted for the insertion of the circuit cutter4 ,the hook1 e1 with which the lower ring1 c1 is in contact1 tends constantly to descend under the action of a spiral spring1 f1 which is connected metallically with the other extremity of the principal conductor4 ,the hooks1 d and e1 are arranged approximately in the same vertical plane1 and have a slightly rounded upper and lower surface1 designed to prevent the rings1 c1 of the fusible wire1 a1 from escaping from the hooks4 ,in ,fig4 #a the position of the arm1 e1 when there is no fusible wire in circuit1 is shown by dotted lines4 ,when this arm occupies the position shown by entire lines1 it exerts a certain traction upon the soldering1 b1 and separates the two halves of the wire1 a1 as soon as the intensity of circulation exceeds its normal value4 ,the mode of putting the wire with fusible soldering into circuit is clearly shown in the engraving4 ,illustration3 ,,fig4 #b4 ,fig4 #b shows a different mode of mounting the wire4 ,the wire1 q1 is soldered in the center1 and is bent into the shape of a ,u1 and kept in place by the pieces1 r and s4 ,in this way the two ends of it tend constantly to separate from each other4 ,messrs4 ,thomson ,bottomley likewise employ weights1 simply1 for submitting the wire to a constant stress4 ,the apparatus is inclosed in a box provided with a glass cover4--,la ,lumiere ,electrique4 99 99 99 99 99 ,,new ,,micro-,,telephonic ,,apparatus4 ,despite the simplicity of their parts1 and the slight value of the materials employed1 the existing micro-telephonic apparatus keep at relatively high prices1 and the use of them is often rejected1 to the benefit of speaking tubes1 when the distance between stations is not too great4 ,we propose to describe a new style of apparatus that are in no wise inferior to those in general use1 and the price of which is relatively low4 ,the microphone transmitter may have several forms4 ,the most elementary of these consists of two pieces of carbon1 from one to one and a quarter inches in length by one-half inch in width1 between which are fixed two nails1 about two inches in length1 whose extremities1 filed to a point1 enter small conical apertures in the carbons4 ,fig4 #a gives an idea of the arrangement4 ,illustration3 ,,fig4 #a4 ,fig4 #b represents a model which is a little more complicated1 but which gives remarkable results4 ,the largest nail is here two inches in length1 and the shortest three-quarter inch4 ,illustration3 ,,fig4 #b4 ,the receivers may be ,bell telephones of the simplest form found in the market 7,fig4 #c72 but for these there may be substituted a bar of soft iron1 cast iron1 or steel1 one of the extremities of which is provided with a bobbin upon1 which is wound insulated copper wire #j4jb inch in diameter4 ,the apparatus is mounted like an ordinary ,bell telephone4 ,a horseshoe electro may also be used1 and the poles be made to act 7,fig4 #d74 ,the current sent by the transmitter suffices to produce a magnetic field in which the variations in intensity produced by the microphone succeed perfectly in reproducing speech and music4 ,with four ,leclanche elements1 the sounds are perceived very clearly4 ,the elements used may be bichromate of potash ones1 those of ,lelande and ,chaperon1 etc4 ,illustration3 ,,fig4 #c4--,,receiver4 ,illustration3 ,,fig4 #d4 ,to this apparatus there may be added a second bobbin of coarser wire into which is passed a current from a local pile4 ,this produces a much intenser magnetic field1 and1 consequently1 louder sounds4 ,this modification1 however1 is really useful only for long distances4 ,any arrangement imaginable may be given the transmitter and receiver2 but1 aside from the fact that the ones just indicated are the simplest1 they give results that are at least equal1 if not superior1 to all others4 ,we shall insist here only upon the arrangement of the microphone1 which is new 7at least in practice71 and upon the uselessness of having well magnetized steel bars and wires of extreme fineness in the receiver4 ,illustration3 ,,fig4 #e4 ,we have stated that the nail microphones are the simplest4 ,the nails may be replaced by copper or any other metal1 or they may be well nickelized2 but common nails answer very well1 and do not oxidize much4 ,an apparatus of this kind 7,fig4 #e7 that has been for more than a year in a laboratory filled with acid vapors is yet working very well4 ,these apparatus possess the further advantage of being very strong1 and of undergoing violent shocks without breaking or even getting out of order4 ,they may be used either with or without induction coils4 ,we have not yet measured their range1 but can cite the following fact3 ,one of these apparatus1 quite crudely mounted1 was put into a circuit with a resistance of #cjj ohms4 ,with a single already exhausted bichromate element1 giving scarcely #b volts1 musical sounds and speech reached the receiver without being notably weakened4 ,such resistance represents a length of eighteen miles of ordinary telegraph wire4 ,after this1 #gjj ohms were overcome with #c4d volts4 ,this result was obtained by direct transmission1 and without an induction coil1 and it is probable that it might be much exceeded without sensibly increasing the electromotive force of the current4--,le ,genie ,civil4 99 99 99 99 99 ,,messrs4 ,,kapp ,,and ,,crompton',s ,,measuring ,,instruments4 ,we give herewith1 from the ,elektrotechnische ,zeitschrift1 a few interesting details in regard to the measuring apparatus of ,messrs4 ,kapp and ,crompton4 ,it is evident that when we use permanent magnets or springs as directing forces in measuring instruments1 we cannot count upon an absolute constancy in the indications1 as the magnetism of the magnetized pieces1 or the tension of the springs1 modifies in time4 ,the apparatus require to be regulated from time to time1 and hence the idea of substituting electro-magnets for permanent ones4 ,illustration3 ,,fig4 #a4 ,if we suppose 7,fig4 #a7 a magnetized needle1 n s1 placed between the extremities of a soft iron core1 ,n ,s1 and if we group the circuit in such a way that the current1 after traversing the coil1 e e1 of the electro1 traverses a circle1 d d1 situated in a plane at right angles with the plane of the needle's oscillation1 it is evident that we shall have obtained an apparatus that satisfies the aforesaid conditions4 ,it seems at first sight that in such an instrument the directing force should be constant from the moment the electro was saturated1 and it would be possible1 were sufficiently thin cores used1 to obtain a constancy in the directing magnetic field for relatively feeble intensities4 ,in reality1 the actions are more complex4 ,the needle1 n s1 is1 in fact1 induced to return to its position of equilibrium by two forces1 the first of which 7the attraction of the poles1 ,n ,s7 rapidly increases with the intensity so as to become quickly and perceptibly constant1 while the second 7the sum of the elementary electrodynamic actions that are exerted between the spirals1 e e1 and the needle1 n s7 increases proportionally to the intensity of the current4 ,if we represent these two sections graphically by referring the magnetic moments as ordinates and the current intensities as abscissas to two co-ordinate axes 7,fig4 #b71 we shall obtain for the first force the curve1 ,o ,a ,b1 which1 starting from ,a1 becomes sensibly parallel with the axis of ,x1 and for the second the right line1 ,o ,d4 ,the resultant action is represented by the curve1 ,o ,e ,e',f4 ,it will be seen that this action1 far from being constant1 increases quite rapidly with the intensity of the current1 so that the deflections would become feebler and feebler for strong intensities1 of current2 and this1 as well known1 would render the apparatus very defective from a practical point of view4 ,illustration3 ,,fig4 #b4 ,but the action of the spirals can be annulled without sensibly diminishing the magnetism of the core by arranging a second system of spirals identical with the first1 but placed in a plane at right angles therewith1 or1 more simply still1 by having a single system of spirals comprising the coil of the electro-magnet1 but distributed in a plane that is oblique with respect to the needle's position of rest4 ,it then becomes possible1 by properly modifying such angle of inclination1 to obtain a total directing action that shall continue to increase with the intensity1 and which1 graphically represented1 shall give the curve1 ,o ,g ,g',h1 for example 7,fig4 #b74 ,illustration3 ,,fig4 #c4 ,illustration3 ,,fig4 #d4 ,illustration3 ,,fig4 #e4 ,this arrangement1 which is adopted in ,mr4 ,kapp's instruments1 gives very good results1 as may be easily seen by reference to ,figs4 #c and #d1 in which the current intensities or differences of potential are referred as ordinates and the degrees of deflection of the needle as abscissas4 ,the unbroken lines represent the curves obtained with the apparatus just described1 while the dotted ones give the curve of deflection of an ordinary tangent galvanometer4 ,these curves show that for strong intensities of current ,mr4 ,kapp's instrument is more advantageous than the tangent galvanometer4 ,mr4 ,crompton has constructed an amperemeter upon the same principle1 which is shown in ,fig4 #e4--,la ,lumiere ,electrique4 99 99 99 99 99 ,,the ,,chemical ,,action ,,of ,,light4 ,professor ,a4 ,vogel1 in a communication to the ,sitzungsberichte der ,munchener ,akademie1 brings into prominence the fact that the hemlock plant1 which yields coniine in ,bavaria1 contains none in ,scotland4 ,hence he concludes that solar light plays a part in the generation of the alkaloids in plants4 ,this view is corroborated by the circumstance that the tropical cinchonas1 if cultivated in our feebly lighted hothouses1 yield scarcely any alkaloids4 ,prof4 ,vogel has proved this experimentally4 ,he has examined the barks of cinchona plants obtained from different conservatories1 but has not found in any of them the characteristic reaction of quinine4 ,of course it is still possible that quinine might be discovered in other conservatory-grown cinchonas1 especially as the specimens operated upon were not fully developed4 ,but as the reaction employed indicates very small quantities of quinine1 it may be safely assumed that the barks examined contained not a trace of this alkaloid1 and it can scarcely be doubted that the deficiency of sunlight in our hothouses is one of the causes of the deficiency of quinine4 ,it will at once strike the reader as desirable that specimens of cinchonas should be cultivated in hothouses under the influence of the electric light1 in addition to that of the sun4 ,if sunlight can be regarded as a factor in the formation of alkaloids in the living plant1 it has1 on the other hand1 a decidedly injurious action upon the quinine in the bark stripped from the tree4 ,on drying such bark in full sunlight the quinine is decomposed1 and there are formed dark-colored1 amorphous1 resin-like masses4 ,in the manufacture of quinine the bark is consequently dried in darkness4 ,this peculiar behavior of quinine on exposure to sunlight finds its parallel in the behavior of chlorophyl with the direct rays of the sun4 ,it is well known that the origin of chlorophyl in the plant is entirely connected with light1 so that etiolated leaves growing in the dark form no chlorophyl4 ,but as soon as chlorophyl is removed from the sphere of vegetable life1 a brief exposure to the direct rays of the sun destroys its green color completely4 ,prof4 ,a4 ,vogel conjectures that the formation of tannin in the living plant is to some extent influenced by light4 ,this supposition is supported by the fact that the proportion of tannin in beech or larch bark increases from below upward--that is1 from the less illuminated to the more illuminated parts1 and this in the proportions of #d3f and #e3aj4 ,sunny mountain slopes of a medium height yield1 according to wide experience1 on an average the pine-barks richest in tannin4 ,in woods in level districts the proportion of tannin is greatest in localities exposed to the light1 while darkness seems to have an unfavorable effect4 ,here1 also1 we must refer to the observation that leaves exceptionally exposed to the light are relatively rich in tannin4 ,we may here add that in the very frequent cases where a leaf is shadowed by another in very close proximity1 or where a portion of a leaf has been folded over by some insect1 the portion thus shaded retains a pale green color1 while adjacent leaves1 or other portions of the same leaf1 assume their yellow1 red1 or brown autumnal tints4 ,if1 as seems highly probable1 these tints are due to transformation products of tannin1 we may not unnaturally conclude that they will be absent where tannin has not been generated4--,jour4 of ,science4 99 99 99 99 99 ,,eutexia4#a ,footnote #a3 ,read before the ,birmingham ,philosophical ,society1 ,january #bb1 #ahhe4 ,by ,,thomas ,,turner1 ,assoc4 ,r4,s4,m41 ,f4,c4,s41 ,demonstrator of ,chemistry1 ,mason ,college4 ,there are a number of interesting facts1 some of which are known to most persons1 and many of them have been long recognized1 of which1 however1 it must be owned that the explanation is somewhat obscure1 and the connections existing between them have been but recently pointed out4 ,as an example of this1 it is well known that salt water freezes at a lower temperature than fresh water1 and hence sea-water may be quite liquid while rivers and ponds are covered with ice4 ,again1 it is noticed that mixtures of salts often have a fusing-point lower than that of either of the constituent salts1 and of this fact we often take advantage in fluxing operations4 ,further1 it is well known that certain alloys can be prepared1 the melting-points of which are lower than the melting-point of either of the constituent metals alone4 ,thus1 while potassium melts at #fb4e ,c41 and sodium at about #ih1 an alloy of these metals is fluid at ordinary temperatures1 and fusible metal melts below the temperature of boiling water1 or more than #aaj lower than the melting-point of tin1 the most fusible of the three metals which enter into the composition of this alloy4 ,but though these and many similar facts have been long known1 it is but recently1 owing largely to the labors of ,dr4 ,guthrie1 that fresh truths have been brought to light1 and a connection shown to exist throughout the whole which was previously unseen1 though we have still to acknowledge that at present there is much at the root of the matter which is but imperfectly understood4 ,still ,dr4 ,guthrie proves a relationship to exist between the several facts we have previously mentioned1 and also between a number of other phenomena which at first sight appear to be equally isolated and unexpected1 and we are asked to regard them all as examples of what he has called eutexia4 ,we may define a eutectic substance as a body composed of two or more constituents1 which constituents are in such proportion to one another as to give to the resultant compound body a minimum temperature of liquefaction--that is1 a lower temperature of liquefaction than that given by any other proportion4#b ,it will be seen at once by this definition that the temperature of liquefaction of a eutectic substance is lower than the temperature of liquefaction of either or any of the constituents of the mixture4 ,and1 further1 it is plain that those substances only can be eutectic which we can obtain both as liquid and solid1 and hence the property of eutexia is closely connected with solution4 ,footnote #b3 ,guthrie1 ,phil4 ,mag4 #e1 xvii41 p4 #dfb4 ,following in the natural divisions adopted by ,dr4 ,guthrie1 we may consider eutexia in three aspects3 ,i4 ,,cryohydrates4 ,if a dilute aqueous saline solution be taken at ordinary temperatures1 and then slowly cooled to some point below zero on the ,centigrade scale1 the following series of changes will in general be observed3 ,on reaching a point below zero1 the position of which is dependent upon the nature of the salt and the amount of dilution1 it will be found that ice is formed2 this will float upon the surface of the solution1 and may be readily removed4 ,if the ice so removed be afterward pressed1 or carefully drained1 it will be found to consist of nearly pure water1 the liquid draining away being a strong saline solution which had become mechanically entangled among the crystals of ice during solidification4 ,if we further cool the brine which remains1 we notice a tolerably uniform fall of temperature with accompanying formation of ice4 ,but at length a point is reached at which the temperature ceases to fall until the whole of the remaining mother-liquor has solidified1 with the production of a compound called a cryohydrate1#c which possesses physical properties different from those of either the ice or the salt from which it is formed4 ,footnote #c3 ,guthrie1 ,phil4 ,mag41 #dth ,series1 xlix41 pp4 #a1 #bjf1 #bff2 #eth ,series1 i41 pp4 #di1 #ced1 #ddf1 vi41 p4 #ce4 ,if1 on the other hand1 we commence with a saturated saline solution1 in general it is noticed on cooling the liquid a separation of salt ensues1 which salt sinks to the bottom of the mass1 and may be removed4 ,the salt so separating may be either anhydrous or a hydrate of greater concentration than the mother-liquor4 ,so long as this separation proceeds the temperature falls1 but at length a point is reached at which the thermometer remains stationary until the whole is solidified1 with the production of a cryohydrate4 ,this temperature of solidification is the same whether we start with a dilute or a saturated solution1 and the composition of the cryohydrate is found to be constant4 ,the temperature of production of the cryohydrate is identical with the lowest temperature which can be produced on employing a mixture of ice and the salt as a freezing mixture or cryogen4 ,it will be readily seen that in the formation of a cryohydrate we have an example of eutexia1 since the constituents are present in such proportion as to give to the resultant compound body a minimum temperature of liquefaction4 ,,ii4 ,,eutectic ,,salt ,,alloys4#d ,footnote #d3 ,f4 ,guthrie1 ,phil4 ,mag4 #e1 xvii41 p4 #dfi2 ,f4,b4 ,guthrie1 ,journ4 ,chem4 ,soc14 #ahhe1 p4 #id4 ,although it has been long known that on mixing certain salts the resulting substance possessed a lower melting-point than either of the constituent salts alone1 still but few determinations of the melting-points of mixtures of salts have been made1 and even these are often of small value1 on account of the very considerable range of temperature observed during solidification4 ,this is due largely to the fact that eutectic mixtures were not known1 as equivalent proportions of various salts have been employed1 while eutectic mixtures are seldom found to possess any simple arithmetical molecular relationship between their constituents4 ,eutectic salt alloys closely resemble cryohydrates in behavior4 ,if for simplicity we confine our attention to a fused mixture of two salts in any proportion other than eutectic1 it is found that1 on cooling1 the thermometer falls steadily1 until at length that salt which is in excess of the proportion required for a eutectic mixture begins to separate out4 ,if this is removed1 the thermometer falls until a fixed point is reached at which the temperature remains stationary until the whole of the mixture solidifies4 ,on remelting1 the temperature of solidification is found to be quite fixed1 and the mixture is evidently eutectic4 ,it is of interest to notice that from our knowledge of the cryohydrates it becomes possible to predict the existence1 composition1 and temperature of solidification of a eutectic alloy1 if we are previously furnished with the melting-points of mixtures of the substances in question4 ,or1 in other cases1 we may predict from the curve of melting-points that no eutectic alloy is possible4 ,as an example1 we may take the determinations of the melting-points of mixtures of potassium and sodium nitrate by ,m4 ,maumen4#e ,these are graphically represented in ,fig4 #a1 the curve being derived from the mean of the temperatures given in the memoir4 ,from this diagram we should be led to expect a eutectic mixture1 since the curve dips below a horizontal line passing through the melting-point of the more fusible of its constituents4 ,from our curve we should expect a eutectic mixture with about #ce per cent4 ,,kno#c1 and with a temperature of solidification below #bcc4 ,dr4 ,guthrie gives #cb4i per cent4 at #bae4 ,this agreement is as good as might be expected when one remembers that the melting-points1 not being of eutectic mixtures1 are difficult to determine1 and a considerable range is given2 that analyses of mixtures of potassium and sodium salts are apt to vary2 and that the two observers differ by #g in the temperatures given for the melting-points of the original salts4 ,footnote #e3 ,comptes ,rendus1 #ahhc1 #b1 p4 #de4 ,illustration3 ,,fig4 #a4 ,dr4 ,tilden has drawn my attention to an interesting example of the lowering of melting-point by the mixture of salts4 ,the melting-point of monohydrochloride of turpentine oil is #abe1 while that of the dihydrochloride is #ej2 but on simply stirring together these compounds in a mortar at common temperatures1 they immediately liquefy4 ,two molecules of the monohydrochloride and one molecule of the dihydrochloride form a mixture which melts at about #bj4 ,,iii4 ,,eutectic ,,metallic ,,alloys4 ,although many fusible alloys have been long known1 ,i believe no true eutectic metallic alloy had been studied until ,dr4 ,guthrie#f worked at the subject1 employing the same methods as with his cryohydrates4 ,it is found if two metals are fused together and the mixture allowed to cool1 that the temperature falls until a point is reached at which that metal which is present in a proportion greater than is required to form the eutectic alloy begins to separate4 ,if this solid be removed as it forms1 the temperature gradually falls until a fixed point is reached1 at which the eutectic alloy solidifies4 ,here the thermometer remains stationary until the whole has become solid1 and1 on remelting1 this temperature is found to be quite fixed4 ,in addition to the di-eutectic alloys1 we have also tri- and tetra-eutectic alloys1 and as an example of the latter we may take the bismuth-tin-lead-cadmium eutectic alloy1 melting at #ga4 ,footnote #f3 ,phil4 ,mag41 #eth ,series1 xvii41 p4 #dfb4 ,we have already seen with salt eutectics that1 given the curve of melting-points of a mixture in various proportions1 we may predict the existence1 composition1 and melting-point of the eutectic alloy4 ,as a matter of course1 the same thing holds good for metallic eutectics4 ,an interesting example of this is furnished by the tin-lead alloys1 the melting-points of which have been determined by ,pillichody4#g ,from these determinations we obtain the curve given in ,fig4 #b1 and from this curve1 since it dips below a horizontal line passing through the melting-point of the more fusible constituent1 we are at once able to predict a eutectic alloy4 ,we should further expect this to have a constitution between ,pb,sn#c and ,pb,sn#d and a melting-point somewhat below #aha4 ,on melting together tin and lead1 and allowing the alloy to cool1 we find our expectation justified2 for by pouring off the fluid portion which remains after solidification has commenced1 and repeating this several times with the portion so removed1 we at length obtain an alloy which solidifies at the constant temperature of #ahj1 when the melting-point of tin is taken as #bbh4 ,on analysis #a4jfd grm4 of this alloy gave #j4hhe grm4 ,sn,o#b1 which corresponds to ,sn #fe4dc per cent41 or ,pb,sn#c4c4 ,this1 therefore1 is the composition of the eutectic alloy1 and it finds its place naturally on the curve given in ,fig4 #b4 ,footnote #g3 ,dingler's ,polyt4 ,journ41 #afb1 p4 #bag2 ,jahresberichte1 #ahfa1 p4 #bgi4 ,illustration3 ,,fig4 #b4 ,it will be seen that the subject of eutexia embraces many points of practical importance and of theoretical interest4 ,thus it has been shown by ,dr4 ,guthrie that the desilverizing of lead in ,pattinson's process is but a case of eutexia1 the separation of lead on cooling a bath of argentiferous lead poor in silver being analogous to the separation of ice from a salt solution4 ,dr4 ,guthrie has also shown that eutexia may reasonably be supposed to have played an important part in the production and separation of many rock-forming minerals4 ,it is with considerable diffidence that ,i suggest the following as an explanation of the multitude of facts to which previous reference has been made4 ,in a mixture of two substances1 ,a and ,b1 we have the following forces active1 tending to produce solidification3 #a4 ,the cohesion between the particles of ,a4 #b4 ,the cohesion between the particles of ,b4 #c4 ,the cohesion between the particles of ,a and the particles of ,b4 ,with regard to this last factor1 it will be seen that there are three cases possible3 #a4 ,the cohesion of the mixture ,a ,b may be greater than the cohesion of ,a the cohesion of ,b4 #b4 ,the cohesion of ,a ,b may be equal to the cohesion of ,a the cohesion of ,b4 #c4 ,the cohesion of ,a ,b may be less than the cohesion of ,a the cohesion of ,b4 ,now1 since cohesion tends to produce solidification1 we should in the first case expect to find the melting-point of the mixture higher than the mean of the melting-points of its constituents1 or the curve of melting-points would be of the form given in a1 ,fig4 #c4 ,here no eutectic mixture is possible4 ,illustration3 ,,fig4 #c4 ,in the second case1 where cohesion ,a ,b cohesion ,a ,b1 we should obtain melting-points for the mixture which would agree with the mean of the melting-points of the constituents1 the curve of melting-points would be a straight line1 and again no eutectic mixture would be possible4 ,in the third case1 however1 where cohesion ,a ,b is less than cohesion ,a ,b1 we should find the melting-points of the mixture lower than the mean of the melting-points of its constituents1 and the curve of melting-points would be of the form given in e1 ,fig4 #c4 ,here1 in those cases where the difference of cohesion on mixture is considerable1 the curve of melting-points may dip below the line e f4 ,this is the only case in which a eutectic mixture is possible1 and it is1 of course1 found at the lowest point of the curve4 ,if it be true1 as above suggested1 that the force of cohesion is at its minimum in the eutectic alloy1 we should expect to find1 in preparing a eutectic substance1 either that actual expansion took place1 or that the molecular volume would gradually increase in passing along our curve of melting-points1 from either end1 for each molecule added1 and that it would obtain its greatest value at the point corresponding to the eutectic alloy4 ,of this ,i have no direct evidence as yet1 but it is a point of considerable interest1 and ,i may possibly return to it at some future time4--,chemical ,news4 99 99 99 99 99 ,,chinoline4 ,dr4 ,conrad ,berens1 of the ,university of ,pennsylvania1 reaches the following3 #a4 ,chinoline tartrate is a powerful agent1 producing death by asphyxia4 #b4 ,the drug increases the force and frequency of the respirations by stimulating the vagus roots in the lung4 #c4 ,it paralyzes respiration finally by a secondary depressant action upon the respiratory center4 #d4 ,it does not cause convulsions4 #e4 ,it lessens and finally abolishes reflex action by a direct action upon the cord1 and by a slight action upon the muscles and nerves4 #f4 ,it diminishes or abolishes muscular contractility respectively when applied through the circulation or directly4 #g4 ,it coagulates myosin and albumen4 #h4 ,it causes insalivation by paralysis of the secretory fibers of the chorda tympani2 increases the flow of bile2 has no action upon the spleen4 #i4 ,it lowers blood-pressure by paralyzing the vaso-motor centers and by a direct depressant action upon the heart muscle4 #aj4 ,it diminishes the pulse rate by direct action upon the heart4 #aa4 ,it lowers the temperature by increasing the loss of heat4 #ab4 ,it is a powerful antiseptic2 and1 finally1 #ac4 ,its paths of elimination are not known4 99 99 99 99 99 ,,method ,,for ,,rapid ,,estimation ,,of ,,urea4 ,being called upon to make a good many brief and rapid analyses of urine on clinic days of our medical department1 ,i devised the following modification of ,knop's method of estimating urea2 and after using it for a year with perfectly satisfactory results1 venture to describe and recommend it as especially adapted for physicians' use1 by reason of simplicity1 cheapness1 and accuracy4 ,in perfecting and testing it ,i was assisted greatly by ,j4 ,torrey1 ,jr41 then working with me4 ,illustration ,the apparatus consists of the glass tube1 ,a1 which is about #h cm4 long and #b cm4 in diameter1 joined to the tube1 ,b1 which is about #be or #cj cm4 in length in its longer arm and #h or #aj in its shorter1 and has a diameter of about #e mm4 ,near the bend is an outlet tube1 c1 provided with ball valve or pinch cock4 d1 e1 f1 g1 are marks upon the tubes4 ,c is a rubber cork with two holes through which the bent tube1 ,d1 passes4 ,d is of such size and length as to hold about #a c4c41 and one of its ends may be a trifle longer than the other4 ,the apparatus is used as follows3 ,remove the cork and pour in mercury until it stands at e and g1 then fill up to the mark1 f1 with sodium or potassium hypobromite 7made by shaking up bromine with a strong solution of sodium or potassium hydroxide74 ,next carefully fill the tube in the cork with the urine1 being careful especially not to run it over or leave air bubbles in it4 ,this can easily be done by using a small pipette1 but if accidentally a little runs over1 it should be wiped off the end of the cork with blotting paper4 ,the cork is then to be inserted closely into the tube2 the urine tube being so small1 the urine will not run out in so doing4 ,the mercury is then drawn out through c till it stands in ,b at d4 ,its level in ,a will of course not be changed greatly4 ,now1 incline the apparatus till the surface of the hypobromite touches the urine in the longer part of the urine tube1 and then bring it upright again4 ,the urine will thus be discharged into the hypobromite1 which will of course decompose the urea1 liberating nitrogen1 which will cause the mercury to rise in ,b4 ,shake until no further change of level is seen1 and mark the level of mercury in ,b with a rubber band1 then remove the cork1 draw out the liquid with a pipette1 dry out the tube above the mercury with scrap of blotting paper1 pour back the mercury drawn out1 and repeat the process to be sure that no error was made4 ,if now two or three marks have been made upon the tube1 ,b1 indicating the height of the mercury when solutions containing known per cents4 of urea are used1 an accurate opinion can be at once formed as to the condition of the urine as regards urea4 ,as is well known1 normal urine contains about #b4e-c per cent4 of urea1 so that graduations representing #b1 #b4e1 #c1 and #d per cent4 are usually all that are needed1 though of course many more can be easily made4 ,the results obtained with this apparatus have been repeatedly compared with those of more elaborate ones1 and no practical difference observed4 ,evidently the same apparatus1 differently graduated1 might be employed to determine the carbonate present in such a substance as crude soda ash or other similar mixture4 ,in such a case the weighed material would be put upon the mercury with water and the small tube filled with acid4 ,bowdoin ,college ,chemical ,laboratory4--,f4,c4 ,robinson1 in ,amer4 ,chem4 ,jour4 99 99 99 99 99 ,a ,,catalogue containing brief notices of many important scientific papers heretofore published in the ,,supplement1 may be had gratis at this office4 99 99 99 99 99 ,,the ,,scientific ,,american ,,supplement4 ,,published ,,weekly4 ,terms of ,subscription1 #e a year4 ,sent by mail1 postage prepaid1 to subscribers in any part of the ,united ,states or ,canada4 ,six dollars a year1 sent1 prepaid1 to any foreign country4 ,all the back numbers of ,,the ,,supplement1 from the commencement1 ,january #a1 #ahgf1 can be had4 ,price1 #aj cents each4 ,all the back volumes of ,,the ,,supplement can likewise be supplied4 ,two volumes are issued yearly4 ,price of each volume1 #b4ej stitched in paper1 or #c4ej bound in stiff covers4 ,,combined ,,rates4--,one copy of ,,scientific ,,american and one copy of ,,scientific ,,american ,,supplement1 one year1 postpaid1 #g4jj4 ,a liberal discount to booksellers1 news agents1 and canvassers4 ,,munn ,,co41 ,,publishers1 #cfa ,,broadway4 ,,new ,,york1 ,n4,y4 99 99 99 99 99 ,,patents4 ,in connection with the ,,scientific ,,american1 ,messrs4 ,,munn ,,co4 are solicitors of ,american and ,foreign ,patents1 have had #dj years' experience1 and now have the largest establishment in the world4 ,patents are obtained on the best terms4 ,a special notice is made in the ,,scientific ,,american of all inventions patented through this ,agency1 with the name and residence of the ,patentee4 ,by the immense circulation thus given1 public attention is directed to the merits of the new patent1 and sales or introduction often easily effected4 ,any person who has made a new discovery or invention can ascertain1 free of charge1 whether a patent can probably be obtained1 by writing to ,,munn ,,co4 ,we also send free our ,hand ,book about the ,patent ,laws1 ,patents1 ,caveats1 ,trade ,marks1 their costs1 and how procured4 ,address ,,munn ,,co41 #cfa ,,broadway1 ,,new ,,york4 ,branch ,office1 cor4 ,f and #gth ,sts41 ,washington1 ,d4,c4