,illustration ,,scientific ,,american ,,supplement ,,no4 #dcj ,,new ,,york1 ,,march #bi1 #ahhd ,scientific ,american ,supplement4 ,vol4 ,,xvii1 ,no4 #dcj4 ,scientific ,american established #ahde ,scientific ,american ,supplement1 #e a year4 ,scientific ,american and ,supplement1 #g a year4 99 99 99 99 99 ,,table ,,of ,,contents4 ,i4 ,,engineering1 ,,mechanics1 ,,etc4--,the ,iron ,industry ,in ,brazil4--,by ,prof4 ,p4 ,,fehrand4--,methods of obtaining iron4--,operation of the system4--,elaboration of the ore4--,setting up a forge4-- ,selling price of iron ,the ,steamer ,churchill1 built by ,messrs4 ,hall1 ,russell ,co41 for service at ,natal4--,with full page of illustrations ,three-,way ,tunnels ,falconetti's ,continuously ,primed ,siphon4--,manner of carrying a water course over a canal1 river1 or road4--,with engraving ,the ,weibel-,piccard ,system of ,evaporating ,liquids4-- #b illustrations ,,ii4 ,,technology4--,coal ,gas as a ,labor--saving ,agent in ,mechanical ,trades4--,by ,t4 ,,fletcher4--,gas as fuel4--,arrangement of burners for disinfection1 for drying glue1 albumen1 etc4--,best burners4 --,gas bars for furnaces1 etc4 ,instantaneous ,photography4--,several illustrations ,,iii4 ,,electricity1 ,,magnetism1 ,,etc4--,electric ,launches4--,a paper read before the ,society of ,arts by ,a4 ,,reckenzaun1 and discussion on the same4--,advantages of electromotive power4-- ,cost of same4--,experimental electric launches ,first ,experiments with the ,electric ,light4--,sir ,humphry ,davy's experiments in #ahac1--,with two engravings ,electrical ,grapnel for ,submarine ,cables and ,torpedo ,lines4-- #c figures ,hughes' ,new ,magnetic ,balance4--#a figure ,apparatus for ,measuring ,small ,resistances4--,with engraving and diagram ,terrestrial ,magnetism4--,magnetism on railways4--,synchronous ,seismology ,,iv4 ,,architecture4--,adornments of the ,new ,post ,office at ,leipzig4-- #b engravings ,v4 ,,natural ,,history1 ,,etc4--,comparison of ,strength of ,large and ,small ,animals4--,by ,w4 ,n4 ,,lockington ,oil in ,california ,,vi4 ,,horticulture1 ,,botany4 ,,etc4--,the ,dodder4--,a new parasitic plant4--,with engraving ,recent ,botanical ,investigations ,,vii4 ,,medicine1 ,,hygiene ,,etc4--,nutritive ,value of ,condiments4--,by ,h4 ,d4 ,,abbott ,,viii4 ,,miscellaneous4--,mont ,st4 ,michel1 ,normandy4--,with engraving 99 99 99 99 99 ,,the ,,dodder4 ,the genus ,cuscuta contains quite a number of species which go under the common name of dodder1 and which have the peculiarily of living as parasites upon other plants4 ,their habits are unfortunately too well known to cultivators1 who justly dread their incursions among cultivated plants like flax1 hops1 etc4 ,all parasitic plants1 or at least the majority of them1 have one character in common which distinguishes them at first sight4 ,in many cases green matter is wanting in their tissues or is hidden by a livid tint that strikes the observer4 ,such are the ,orobanchacc1 or broomropes1 and the tropical ,balanophorace4 ,nevertheless1 other parasites1 such as the mistletoe1 have perfectly green leaves4 ,however this may be1 the naturalist's attention is attracted every time he finds a plant deprived of chlorophyl1 and one in which the leaves seem to be wanting1 as in the dodder that occupies us4 ,in fact1 as the majority of parasites take their nourishment at the expense of the plants upon which they fasten themselves1 they have no need1 as a general thing1 of elaborating through their foliar organs the materials that their hosts derive from the air2 in a word1 they do not breathe actively like the latter1 since they find the elements of their nutrition already prepared in the sap of their nurses4 ,the dodders1 then1 are essentially parasites1 and their apparent simplicity gives them a very peculiar aspect4 ,their leaves are wholly wanting1 or are indicated by small1 imperceptible scales1 and their organs of vegetation are reduced to a stem and filiform branches that have obtained for them the names of ,cheveux de ,venus 7,venus' ,hair7 and ,cheveux du ,diable 7devil's hair7 in ,french1 and gold thread in ,english4 ,because of their destructive nature they have likewise been called by the unpoetic name of hellweed2 and1 for the reason that they embrace their host plants so closely1 they have been called love weed and love vine4 ,when a seed of ,cuscuta1 germinates1 no cotyledons are to be distinguished4 ,this peculiarity1 however1 the plant has in common with other parasites1 and even with some plants1 such as orchids1 that vegetate normally4 ,the radicle of the dodder fixes itself in the earth1 and the little stem rises as in other dicotyledons2 but soon 7for the plantlet could not live long thus7 this stem1 which is as slender as a thread1 seeks support upon some neighboring plant1 and produces upon its surfaces of contact one or more little protuberances that shortly afterward adhere firmly to the support and take on the appearance and functions of cupping glasses4 ,at this point there forms a prolongation of the tissue of the dodder--a sort of cone1 which penetrates the stalk of the host plant4 ,after this1 through the increase of the stem and branches of the parasite1 the supporting plant becomes interlaced on every side1 and1 if it does not die from the embraces of its enemy1 its existence is notably hazarded4 ,it is possible for a ,cuscuta plant to work destruction over a space two meters in diameter in a lucern or clover field2 so1 should a hundred seeds germinate in an acre1 it may be easily seen how disastrous the effects of the scourge would prove4 ,these enemies of our agriculture were scarcely to be regarded as injurious not very many years ago1 for the reason that their sources of development were wanting4 ,lucern and clover are comparatively recent introductions into ,france1 at least as forage plants4 ,other cultures are often sorely tried by the dodder1 and what is peculiar is that there are almost always species that are special to such or such a plant1 so that the botanist usually knows beforehand how to determine the parasite whose presence is made known to him4 ,thus1 the ,cuscuta of flax1 called by the ,french ,bourreau du ,lin 7the flax's executioner71 and by the ,english1 flax dodder1 grows only upon this textile plant1 the crop of which it often ruins4 ,on account of this1 botanists call this species ,cuscuta epilinum4 ,others1 such as ,c4 ,europa1 attack by preference hemp and nettle4 ,finally1 certain species are unfortunately indifferent and take possession of any plant that will nourish them4 ,of this number is the one that we are about to speak of4 ,attempts have sometimes been made out of curiosity to cultivate exotic species4 ,one of the head gardeners at the ,paris ,museum received specimens of ,cuscuta reflexa from ,india about two years ago1 and1 having placed it upon a geranium plant1 succeeded in cultivating it4 ,since then1 other plants have been selected1 and the parasite has been found to develop upon all of them4 ,what adds interest to this species is that its flowers are relatively larger and that they emit a pleasant odor of hawthorn4 ,mr4 ,hamelin thinks that by reason of these advantages1 an ornamental plant might be made of it1 or at least a plant that would be sought by lovers of novelties4 ,like the majority of dodders1 this species is an annual1 so that1 as soon as the cycle of vegetation is accomplished1 the plant dies after flowering and fruiting4 ,but here the seeds do not arrive at maturity1 and the plant has to be propagated by a peculiar method4 ,at the moment when vegetation is active1 it is only necessary to take a bit of the stem1 and then1 after previously lifting a piece of the bark of the plant upon which it is to be placed1 to apply this fragment of ,cuscuta thereto 7as in grafting71 place the bark over it1 and bind a ligature round the whole4 ,in a short time the graft will bud1 and in a few months the host plant will be covered with it4 ,the genus ,cuscuta embraces more than eighty species1 which are distributed throughout the entire world1 but which are not so abundant in cold as in warm regions4--,la ,nature4 ,illustration3 ,a ,,new ,,exotic ,,dodder4 7,cuscuta ,reflexa47 99 99 99 99 99 ,,recent ,,botanical ,,investigations4 ,it is commonly said that there is a great difference between the transpiration and evaporation of water in plants4 ,the former takes place in an atmosphere saturated with moisture1 it is influenced by light1 by an equable temperature1 while evaporation ceases in a saturated atmosphere4 ,m4 ,leclerc has very carefully examined this question1 and he concludes that transpiration is only the simple evaporation of water4 ,if transpiration is more active in the plant exposed to the sun1 that is due to the heat rays1 and in addition arises in part from the fact that the assimilating action of chlorophyl heats the tissues1 which in turn raises the temperature and facilitates evaporation4 ,as to transpiration taking place in a saturated atmosphere1 it is a mistake2 generally there is a difference in the temperature of the plant and the air1 and the air is not saturated in its vicinity4 ,in a word1 transpiration and evaporation is the same thing4 ,herr ,reinke has made an interesting examination of the action of light on a plant4 ,he has permitted a pencil of sun rays to pass through a converging lens upon a cell containing a fragment of an aquatic plant4 ,he was enabled to increase the intensity of the light1 so that it should be stronger or weaker than the direct sunlight4 ,he could thus vary its intensity from #a_/af of that of direct sunlight to an intensity #fd times stronger4 ,the temperature was maintained constant4 ,herr ,reinke has shown that the chlorophyl action increases regularly with the light for intensities under that of direct sunlight2 but what is unexpected1 that for the higher intensities above that of ordinary daylight the disengagement of oxygen remains constant4 ,m4 ,leclerc du ,sablon has published some of his results in his work on the opening of fruits4 ,the influences which act upon fruit are external and internal4 ,the external cause of dehiscence is drying4 ,we can open or shut a fruit by drying or wetting it4 ,the internal causes are related to the arrangement of the tissues1 and we may say that the opening of fruit can be easily explained by the contraction of the ligneous fibers under drying influences4 ,m4 ,leclerc shows by experiment that the fibers contract more transversely than longitudinally1 and that the thicker fibers contract the most4 ,this he finds is connected with the opening of dry fruits4 ,herr ,hoffman has recently made some interesting experiments upon the cultivation of fruits4 ,it is well known that many plants appear to select certain mineral soils and avoid others1 that a number of plants which prefer calcareous soils are grouped together as calcicoles1 and others which shun such ground as calcifuges4 ,herr ,hoffman has grown the specimen which has been cited by many authors as absolutely calcifugic4 ,he has obtained strong plants upon a soil with #ec per cent4 of lime1 and these have withstood the severe winter of #ahgi-ahhj1 while individuals of the same species grown on silicious ground have failed4 ,this will modify the ideas of agriculturists1 at least in regard to this plant4 ,herr ,schwarz has been engaged in the study of the fine hairs of roots4 ,according to this author1 there is a maximum and minimum of humidity1 between which there lies a mean of moisture1 most favorable for the development of these capillary rootlets1 and this amount of moisture varies with different plants4 ,he finds that this growth of hair-like roots is conditioned upon the development of the main root from which it springs4 ,in a weak solution of brine these fine roots are suppressed1 while the growth of the main root is continued4 ,the changes of the milieu lead to changes in the form of the hairs1 rendering them even branched4 ,signor ,savastano has ventured to criticise as exaggerated the views of ,muller1 ,lubbock1 and ,allen on the adaptation of flowers to insects1 having noticed that bees visit numbers of flowers1 and extract their honey without touching the stigmas or pistils4 ,he has also found them neglecting flowers which were rich in honey and visiting others much poorer4 ,these observations have value1 but cannot be considered as seriously impairing the multiplied evidences of plant adaptation to insect life4 ,mr4 ,camus has shown that the flora of a small group of hills1 the ,euganean ,mountains1 west of the ,apennines and south of the ,alps1 has a peculiar flora1 forming an island in the midst of a contrasted flora existing about it4 ,here are found ,alpine1 maritime1 and exotic plants associated in a common isolation4--,revue ,scientifique4 99 99 99 99 99 ,,recent ,,botanical ,,advances4 ,among the most significant of the recent discoveries in botany1 is that respecting the continuity of the protoplasm from cell to cell1 by means of delicate threads which traverse channels through the cell walls4 ,it had long been known1 that in the sieve tissues of higher plants there was such continuity through the sieve plates1 which imperfectly separated the contiguous cells4 ,this may be readily seen by making longitudinal sections of a fibro-vascular bundle of a pumpkin stem1 staining with iodine1 and contracting the protoplasm by alcohol4 ,carefully made specimens of the soft tissues of many plants have shown a similar protoplasmic continuity1 where it had previously been unsuspected4 ,some investigators are now inclined to the opinion that protoplasmic continuity may be of universal occurrence in plants4 99 99 99 99 99 ,,electric ,,launches4 ,footnote3 ,a recent lecture before the ,society of ,,atm1 ,london4 ,by ,a4 ,,reckenzaun4 ,it is not my intention to treat this subject from a shipwright's point of view4 ,the title of this paper is supposed to indicate a mode of propelling boats by means of electrical energy1 and it is to this motive power that ,i shall have the honor of drawing your attention4 ,the primary object of a launch1 in the modern sense of the word1 lies in the conveyance of passengers on rivers and lakes1 less than for the transport of heavy goods2 therefore1 it may not be out of place to consider the conveniences arising from the employment of a motive power which promises to become valuable as time and experience advance4 ,in a recent paper before the ,british ,association at ,southport1 ,i referred to numerous experiments made with electric launches2 now it is proposed to treat this subject in a wider sense1 touching upon the points of convenience in the first place2 secondly1 upon the cost and method of producing the current of electricity2 and thirdly1 upon the construction and efficiency of the propelling power and its accessories4 ,whether it is for business1 pleasure1 or war purposes a launch should be in readiness at all times1 without requiring much preparation or attention4 ,the distances to be traversed are seldom very great1 fifty to sixty miles being the average4 ,nearly the whole space of a launch should be available for the accommodation of passengers1 and this is the case with an electrically propelled launch4 ,we have it on good authority1 that an electric launch will accommodate nearly double the number of passengers that a steam launch of the same dimensions would2 therefore1 for any given accommodation we should require a much smaller vessel1 demanding less power to propel it at a given rate of speed1 costing less1 and affording easier management4 ,a further convenience arising from electromotive power is the absence of combustibles and the absence of the products of combustion-matters of great importance2 and for the milder seasons1 when inland navigation is principally enjoyed1 the absence of heat1 smell1 and noise1 and1 finally1 the dispensing with one attendant on board1 whose wages1 in most cases1 amount to as much or more than the cost of fuel1 besides the inconvenience of carrying an additional individual4 ,i do not know whether the cost of motive power is a serious consideration with proprietors of launches1 but it is evident that if there be a choice between two methods of equal qualities1 the most economical method will gain favor4 ,the motive power on the electric launch is the electric current2 we must decide upon the mode of procuring the current4 ,the mode which first suggested itself to ,professor ,jacobi1 in the year #ahch1 was the primary battery1 or the purely chemical process of generating electricity4 ,jacobi employed1 in the first instance1 a ,daniell's battery1 and in later experiments with his boat on the river ,neva1 a ,grove's battery4 ,the ,daniell's battery consisted of #cbj cells containing plates of copper and zinc2 the speed attained by the boat with this battery did not reach one mile and a quarter per hour2 when #fd ,grove cells were substituted1 the speed came to two and a quarter miles per hour2 the boat was #ch feet long4 #g beam1 and #c feet deep4 ,the electromotor was invented by ,professor ,jacobi2 it virtually consisted of two disks1 one of which was stationary1 and carried a number of electromagnets1 while the other disk was provided with pieces of iron serving as armatures to the pole pieces of the electromagnets1 which were attracted while the electric current was alternately conveyed through the bobbins by means of a commutator1 producing continuous rotation4 ,we are not informed as to the length of time the batteries were enabled to supply the motor with sufficient current1 but we may infer from the surface of the acting materials in the battery that the run was rather short2 the power of the motor was evidently very small1 judging by the limited speed obtained1 but the originality of ,jacobi deserves comment1 and for this1 as well as for numerous other researches1 his name will be remembered at all times4 ,it may not be generally known that an electric launch was tried for experimental purposes1 on a lake at ,pentlegaer1 near ,swansea4 ,mr4 ,robert ,hunt1 in the discussion of his paper on electromagnetism before the ,institution of ,civil ,engineers in #aheh1 mentioned that he carried on an extended series of experiments at ,falmouth1 and at the instigation of ,benkhausen1 ,russian ,consul-,general1 he communicated with ,jacobi upon the subject4 ,in the year #ahdh1 at a meeting of the ,british ,association at ,swansea1 ,mr4 ,hunt was applied to1 by some gentlemen connected with the copper trade of that part1 to make some experiments on the electrical propulsion of vessels2 they stated1 that although electricity might cost thirty times as much as the power obtained from coal it would1 nevertheless1 be sufficiently economical to induce its employment for the auxiliary screw ships employed in the copper trade with ,south ,america4 ,the boat at ,swansea was partly made under ,mr4 7now ,sir ,william7 ,grove's directions1 and the engine was worked on the principle of the old toys of ,ritchie1 which consisted of six radiating poles projecting from a spindle1 and rotating between a large electro-magnet4 ,three persons traveled in ,hunt's boat1 at the rate of three miles per hour4 ,eight large ,grove's cells were employed1 but the expense put it out of question as a practical application4 ,had the ,gramme or ,siemens machine existed at that time1 no doubt the subject would have been further advanced1 for it was not merely the cost of the battery which stood in the way1 but the inefficient motor1 which returned only a small fraction of the power furnished by the zinc4 ,professor ,silvanus ,thompson informs us that an electric boat was constructed by ,mr4 ,g4 ,e4 ,dering1 in the year #ahef1 at ,messrs4 ,searle's yard1 on the ,river ,thames2 it was worked by a motor in which rotation was effected by magnets arranged within coils1 like galvanometer needles1 and acted on successively by currents from a battery4 ,from a recent number of the ,annales de l',electricite1 we learn that ,count de ,moulins experimented on the lake in the ,bois de ,boulogne1 in the year #ahff1 with an iron flat-bottomed boat1 carrying twelve persons4 ,twenty ,bunsen cells furnished the current to a motor on ,froment's principle turning a pair of paddle wheels4 ,in all these reports there is a lack of data4 ,we are interested to know what power the motors developed1 the time and speed1 as well as dimensions and weights4 ,until ,trouve's trip on the ,seine1 in #ahha1 and the launch of the ,electricity on the ,thames1 in #ahhb1 very little was known concerning the history of electric navigation4 ,m4 ,trouve originally employed ,plante's secondary battery1 but afterward reverted to a bichromate battery of his own invention4 ,in all the primary batteries hitherto applied with advantage1 zinc has been used as the acting material4 ,where much power is required1 the consumption of zinc amounts to a formidable item2 it costs1 in quantity1 about #c;d4 per pound1 and in a well arranged battery a definite quantity of zinc is transformed4 ,the final effect of this transformation manifests itself in electrical energy1 amounting to about #gdf watts1 or one electrical horse power for every two pounds of this metal consumed per hour4 ,the cost of the exciting fluid varies1 however1 considerably2 it may be a solution of salts1 or it may be dilute acid4 ,considering the zinc by itself1 the expense for five electrical or four mechanical horse power through an efficient motor1 in a small launch1 would be #bs4 #f;d4 per hour4 ,many persons would willingly sacrifice #bs4 #f;d per hour for the convenience1 but a great item connected with the employment of zinc batteries is in the exciting fluid1 and the trouble of preparing the zinc plates frequently4 ,the process of cleaning1 amalgamating and refilling is so tedious1 that the use of primary batteries for locomotive purposes is extremely limited4 ,to recharge a ,bunsen1 ,grove1 or bichromate battery1 capable of giving six or seven hours' work at the rate of five electrical horse power1 would involve a good day's work for one man2 no doubt he would consider himself entitled to a full day's wages1 with the best appliances to assist him in the operation4 ,several improved primary batteries have recently been brought out1 which promise economical results4 ,if the residual compound of zinc can be utilized1 and sold at a good price1 then the cost of such motive power may be reduced in proportion to the value of those by-products4 ,for the purpose of comparison1 let us now employ the man who would otherwise clean and prepare the primary cells1 at engine driving4 ,we let him attend to a six horse power steam engine1 boiler1 and dynamo machine for charging #ej accumulators1 each of a capacity of #cgj ampere hours1 or one horse power hour4 ,the consumption of fuel will probably amount to #dj lb4 per hour1 which1 at the rate of #ahs4 a ton1 will give an expenditure of nearly #d;d4 per hour4 ,the energy derived from coal in the accumulator costs1 in the case of a supply of five electrical horse power for seven hours1 #bs4 #i;d42 the energy derived from the zinc in a primary battery1 supplying five electrical horse power for seven hours1 would cost #ags4 #c;d4 ,it is hardly probable that any one would lay down a complete plant1 consisting of a steam or gas engine and dynamo1 for the sole purpose of charging the boat cells1 unless such a boat were in almost daily use1 or unless several boats were to be supplied with electrical power from one station4 ,in order that electric launches may prove useful1 it will be desirable that charging stations should be established1 and on many of the ,british and ,irish rivers and lakes there is abundance of motive power1 in the shape of steam or gas engines1 or water-wheels4 ,a system of hiring accumulators ready for use may1 perhaps1 best satisfy the conditions imposed in the case of pleasure launches4 ,it is difficult to compile comparative tables showing the relative expenses for running steam launches1 electric launches with secondary batteries1 and electric launches with primary zinc batteries2 but ,i have roughly calculated that1 for a launch having accommodation for a definite number of passengers1 the total costs are as #a1 #b4e1 and #ab respectively1 steam being lowest and zinc batteries highest4 ,the accumulators are1 in this case1 charged by a small high pressure steam engine1 and a very large margin for depreciation and interest on plant is added4 ,the launch taken for this comparison must run during #b1jjj hours in the year1 and be principally employed in a regular passenger service1 police and harbor duties1 postal service on the lakes and rivers of foreign countries1 and the like4 ,the subject of secondary batteries has been so ably treated by ,professor ,silvanus ,thompson and ,dr4 ,oliver ,lodge1 in this room1 that ,i should vainly attempt to give you a more complete idea of their nature4 ,the improvements which are being made from time to time mostly concern mechanical details1 and although important1 a description will scarcely prove interesting4 ,a complete ,faure-,sellon-,volckmar cell1 such as is used in the existing electric launches1 is here on the table2 this box weighs1 when ready for use1 #ef lb42 and it stores energy equal to one horse power for one hour#a1ihj1jjj foot pounds1 or about one horse power per minute for each pound weight of material4 ,it is not advantageous to withdraw the whole amount of energy put in2 although its charging capacity is as much as #cgj ampere hours1 we do not use more than #hj per cent41 or #cjj ampere hours2 hence1 if we discharge these accumulators at the rate of #dj amperes1 we obtain an almost constant current for #g hours3 one cell gives an ,e4,m4,f4 of two volts4 ,in order to have a constant power of one horse for #g hours1 at the rate of #dj amperes discharge1 we must have more than nine cells per electrical horsepower2 and #dg such cells will supply five electrical horse power for the time stated1 and these #dg cells will weigh #b1fcc lb4 ,we could employ half the number of cells by using them at the rate of #hj amperes1 but then they will supply the power for less than half the time4 ,the fact1 however1 that the cells will give so high a rate of discharge for a few hours is1 in itself1 important1 since we are enabled to apply great power if desirable2 the #dg cells above referred to can be made to give #aj or #ab electrical horse power for over two hours1 and thus propel the boat at a very high speed1 provided that the motor is adapted to utilize such powerful currents4 ,the above mentioned weight of battery power--viz41 #b1fcb lb41 to which has to be added the weight of the motor and the various fittings--represents1 in the case of a steam launch1 the weight of coals1 steam boiler1 engine1 and fittings4 ,the electro motor capable of giving four horse power on the screw shaft need not weigh #djj lb4 if economically designed2 this added to the weight of the accumulators1 and allowing a margin for switches and leads1 brings the whole apparatus up to about #bh cwt4 ,an equally powerful launch engine and boiler1 together with a maximum stowage of fuel1 will weigh about the same4 ,there is1 however1 this disadvantage about the steam power1 that it occupies the most valuable part of the vessel1 taking away some eight or nine feet of the widest and most convenient part1 and in a launch of twenty-four feet length1 requiring such a power as we have been discussing1 this is actually one-third of the total length of the vessel1 and one-half of the passenger accommodation2 therefore1 ,i may safely assert that an electric launch will carry about twice as many people as a steam launch of similar dimensions4 ,the diagram on the wall represents sections of an electric launch built by ,messrs4 ,yarrow and ,company1 and fitted up by the ,electrical ,power ,storage ,company1 for the recent ,electrical ,exhibition in ,vienna4 ,she has made a great number of successful voyages on the ,river ,danube during the autumn4 ,her hull is of steel1 #dj feet long and #f feet beam1 and there are seats to accommodate forty adults comfortably4 ,her accumulators are stowed away under the floor1 so is the motor1 but owing to the lines of the boat the floor just above the motor is raised a few inches4 ,this motor is a ,siemens ,d#b machine1 capable of working up to seven horse power with eighty accumulators4 ,in speaking of the horse power of an electro motor1 ,i always mean the actual power developed in the shaft1 and not the electrical horse power2 this1 therefore1 should not be compared to the indicated horse power of a steam engine4 ,i am indebted to ,messrs4 ,yarrow for the principal dimensions and other particulars of a high pressure launch engine and boiler1 such as would be suitable for this boat4 ,from these dimensions ,i prepared a second diagram representing the steam power1 and when placed in position it will show at a glance how much space this apparatus will occupy4 ,the total length lost in this way amounts to #ab feet1 leaving for testing capacity only #ae feet1 while that of the electric launch is #bg feet on each side of the boat2 thus the accommodation is as fifteen to twenty-seven1 or as twenty-two passengers to forty1 in favor of the electric launch4 ,comparing the relative weights of the steam power and the electric power for this launch1 we find that they are nearly equal--each approaches #ej cwt2 but in the case of the steam launch we include #aj cwt4 of coals1 which can be stowed into the bunkers1 and which allow fifteen hours continuous steaming1 whereas the electric energy stored up will only give us seven and a half hours with perfect safety4 ,i have here allowed #h lb4 of coal per indicated horse power per hour1 and #aj horse power giving off #g mechanical horse power on the screw shaft2 this is an example of an average launch engine4 ,there are launch engines in existence which do not consume one-half that amount of fuel1 but these are so few1 so rare1 and so expensive1 that ,i have neglected them in this account4 ,not many years ago1 a steam launch carrying a seven hours supply of fuel was considered marvelous4 ,our present accumulaton supplies #cc1jjj foot pounds of work per pound of lead1 but theoretically one pound of lead manifests an energy equal to #cfj1jjj foot pounds in the separation from its oxide2 and in the case of iron1 ,prof4 ,osborne ,reynolds told us in this place1 the energy evolved by its oxidation is equivalent to #a1ijj1jjj foot pounds per pound of metal4 ,how nearly these limits may be approached will he the problem of the chemist2 to prophesy is dangerous1 while science and its applications are advancing at this rapid rate4 ,theoretically1 then1 with our weight of fully oxidized lead we should be able to travel for #hb hours2 with the same weight of iron for #dcj hours1 or #ah days and nights continually1 at the rate of #h miles per hour1 with one change4 ,of course1 these feats are quite impossible4 ,we might as well dream of getting #e horse power out of a steam engine for one pound of coal per hour4 ,while the chemist is busy with his researches for substances and combinations which will yield great power with small quantities of material1 the engineer assiduously endeavors to reconvert the chemical or electrical energy into mechanical work suitable to the various needs4 ,to get the maximum amount of work with a minimum amount of weight1 and least dimensions combined with the necessary strength is the province of the mechanical engineer--it is a grand and interesting study2 it involves many factors2 it is not1 as in the steam engine and hydraulic machine1 a matter of pressures1 tension and compression1 centrifugal and static forces1 but it comprises a still larger number of factors1 all bearing a definite relation to each other4 ,with dynamo machines the aim has been to obtain as nearly as possible as much electrical energy out of the machine as has been put in by the prime mover1 irrespective of the quantity of material employed in its construction4 ,dr4 ,j4 ,hopkinson has not only improved upon the ,edison dynamo1 and obtained #id per cent4 of the power applied in the form of electrical energy1 but he got #ej horse power out of the same quantity of iron and copper where ,edison could only get #bj horsepower--and1 though the efficiency of this generator is perfect1 it could not be called an efficient motor1 suitable for locomotion by land or water1 because it is still too heavy4 ,an efficient motor for locomotion purposes must not only give out in mechanical work as nearly as possible as much as the electrical energy put in1 but it must be of small weight1 because it has to propel itself along with the vehicle1 and every pound weight of the motor represents so many foot pounds of energy used in its own propulsion2 thus1 if a motor weighed #ffj pounds1 and were traveling at the rate of #ej feet per minute1 against gravitation1 it would expend #cc1jjj foot pounds per minute in moving itself1 and although this machine may give #b horse power1 with an efficiency of #ij per cent4 it would1 in the case of a boat or a tram-car1 be termed a wasteful machine4 ,here we have an all-important factor which can be neglected1 to a certain extent1 in the dynamo as a generator1 although from an economical point of view excessive weight in the dynamo must also be carefully avoided4 ,the proper test for an electro-motor1 therefore1 is not merely its efficiency1 or the quotient of the mechanical power given out1 divided by the electrical energy put in1 but also the number of feet it could raise its own weight in a given space of time1 with a given current1 or1 in other words1 the number of foot pounds of work each pound weight of the motor would give out4 ,the ,siemens ,d#b machine1 as used in the launch shown in the diagram on the wall1 is one of the lightest and best motors1 it gives #g horse power on the shaft1 with an expenditure of #i electrical horsepower1 and it weighs #feh lb42 its efficiency1 therefore1 #g_/e or nearly #gh per cent42 but its coefficient as an engine of locomotion is #cea--that is to say1 each pound weight of the motor will yield #cea foot pounds on the shaft4 ,we could get even more than #g horse power out of this machine1 by either running it at an excessive speed1 or by using excessive currents2 in both cases1 however1 we should shorten the life of the apparatus4 ,an electro-motor consists1 generally1 of two or more electro-magnets so arranged that they continually attract each other1 and thereby convey power4 ,as already stated1 there are numerous factors1 all bearing a certain relationship to each other1 and particular rules which hold good in one type of machine will not always answer in another1 but the general laws of electricity and magnetism must be observed in all cases4 ,with a given energy expressed in watts1 we can arrange a quantity of wire and iron to produce a certain quantity of work2 the smaller the quantity of material employed1 and the larger the return for the energy put in1 the greater is the total efficiency of the machine4 ,powerful electro-magnets1 judiciously arranged1 must make powerful motors4 ,the ease with which powerful electro-magnets can be constructed has led many to believe that the power of an electro-motor can be increased almost infinitely1 without a corresponding increase of energy spent4 ,the strongest magnet can be produced with an exceedingly small current1 if we only wind sufficient wire upon an iron core4 ,an electro-magnet excited by a tiny battery of #aj volts1 and1 say1 one ampere of current1 may be able to hold a tremendous weight in suspension1 although the energy consumed amounts to only #aj watts1 or less than #a_/ge of a horse power1 but the suspended weight produces no mechanical work4 ,mechanical work would only be done if we discontinued the flow of the current1 in which case the said weight would drop2 if the distance is sufficiently small1 the magnet could1 by the application of the current from the battery1 raise the weight again1 and if that operation is repeated many times in a minute1 then we could determine the mechanical work performed4 ,assuming that the weight raised is #a1jjj lb41 and that we could make and break the current two hundred times a minute1 then the work done by the falling mass could1 under no circumstances1 equal #a_/ge of a horse-power1 or #ddj foot-pounds2 that is1 #a1jjj lb4 lifted #b4bg feet high in a minute1 or about one-eighth of an inch for each operation3 hence the mere statical pull1 or power of the magnet1 does in no way tend to increase the energy furnished by the battery or generator1 for the instant we wish to do work we must have motion--work being the product of mass and distance4 ,large sums of money have virtually been thrown away in the endeavor to produce energy1 and there are intelligent persons who to this day imagine that1 by indefinitely increasing the strength of a magnet1 more power may be got out of it than is put in4 ,large field-magnets are advantageous1 and the tendency in the manufacture of dynamo machines has been to increase the mass of iron1 because with long and heavy cores and pole pieces there is a steady magnetism insured1 and therefore a steady current1 since large masses of iron take a long time to magnetize and demagnetize2 thus very slight irregularites in the speed of an armature are not so easily perceived4 ,in the case of electro-motors these conditions are changed4 ,in the first place1 we assume that the current put through the coils of the magnets is continuous2 and secondly1 we can count upon the momentum of the armature1 as well as the momentum of the driven object1 to assist us over slight irregularities4 ,with electric launches we are bound to employ a battery current1 and battery currents are perfectly continuous--there are no sudden changes2 it is consequently a question as to how small a mass of iron we may employ in our dynamo as a motor without sacrificing efficiency4 ,the intensity of the magnetic field must be got by saturating the iron1 and the energy being fixed1 this saturation determines the limit of the weight of the iron4 ,soft wrought iron1 divided into the largest possible number of pieces1 will serve our purpose best4 ,the question of strength of materials plays also an important part4 ,we cannot reduce the quantity and division to such a point that the rigidity and equilibrium of the whole structure is in any way endangered4 ,the armature1 for instance1 must not give way to the centrifugal forces imposed upon it1 nor should the field magnets be so flexible as to yield to the statical pull of the magnetic poles4 ,the compass of this paper does not permit of a detailed discussion of the essential points to be observed in the construction of electro-motors2 a reference to the main points1 may1 however1 be useful4 ,the designer has1 first of all1 to determine the most effective positions of the purely electrical and magnetic parts2 secondly1 compactness and simplicity in details2 thirdly1 easy access to such parts as are subject to wear and adjustment2 and1 fourthly1 the cost of materials and labor4 ,the internal resistance of the motor should be proportioned to the resistances of the generator and the conductors leading from the generator to the receiver4 ,the insulation resistances must be as high as possible2 the insulation can never be too good4 ,the motor should he made to run at that speed at which it gives the greatest power with a high efficiency1 without heating to a degree which would damage the insulating material4 ,before fixing a motor in its final position1 it should also be tested for power with a dynamometer1 and for this purpose a ,prony brake answers very well4 ,an ammeter inserted in the circuit will show at a glance what current is passing at any particular speed1 and voltmeter readings are taken at the terminals of the machine1 when the same is standing still as well as when the armature is running1 because the ,e4,m4,f4 indicated when the armature is at rest alone determines the commercial efficiency of the motor1 whereas the ,e ,m4,f4 developed during motion varies with the speed until it nearly reaches the ,e4,m4,f4 in the leads2 at that point the theoretical efficiency will be highest4 ,calculations are greatly facilitated1 and the value of tests can be ascertained quickly1 if the constant of the brake is ascertained2 then it will be simply necessary to multiply the number of revolutions and the weight at the end of the lever by such a constant1 and the product gives the horse power1 because1 with a given ,prony brake1 the only variable quantities are the weight and the speed4 ,all the observations1 electrical and mechanical1 are made simultaneously4 ,the electrical horse power put into the motor is found by the well known formula ,c x ,e _/ #gdf2 this simple multiplication and division becomes very tedious and even laborious if many tests have to be made in quick succession1 and to obviate this trouble1 and prevent errors1 ,i have constructed a horse power diagram1 the principle of which is shown in the diagram 7,fig4 #a74 ,graphic representations are of the greatest value in all comparative tests4 ,mr4 ,gisbert ,kapp has recently published a useful curve in the ,electrician1 by means of which one can easily compare the power and efficiency at a glance 7,fig4 #b74 ,the speeds are plotted as abscissae1 and the electrical work absorbed in watts divided by #gdf as ordinates2 then with a series-wound motor we obtain the curve1 ,,ee4 ,the shape of this curve depends on the type of the motor4 ,variation of speed is obtained by loading the brake with different weights4 ,we begin with an excess of weight which holds the motor fast1 and then a maximum current will flow through it without producing any external work4 ,when we remove the brake altogether1 the motor will run with a maximum speed1 and again produce no external work1 but in this case very little current will pass2 this maximum speed is om on the diagram4 ,between these two extremes external work will be done1 and there is a speed at which this is a maximum4 ,to find these speeds we load the brake to different weights1 and plot the resulting speeds and horse powers as abscissae and ordinates producing the curve1 ,,bb4 ,another curve1 e ,b_/,e made with an arbitrary scale1 gives the commercial efficiency2 the speed for a maximum external horse power is o a1 and the speed for the highest efficiency is represented by o b4 ,in practice it is not necessary to test a motor to the whole limits of this diagram2 it will be sufficient to commence with a speed at which the efficiency becomes appreciable1 and to leave off with that speed which renders the desired power4 ,i have now to draw your attention to a new motor of my own invention1 of the weight of #abd lb41 which1 at #a1eej revolutions1 gives #ca amperes and #fa4e volts at terminals4 ,the mechanical horse power is #a4cg1 and the coefficient #cgc4 ,ohms4 ,armature resistance #j4d w4 ,field-magnet resistance #j4ag w4 ,insulation resistance #a1ejj1jjj w4 ,this motor was only completed on the morning before reading the paper2 it could not1 therefore1 be tested as to its various capacities4 ,we have next to consider the principle of applying the motive power to the propulsion of a launch4 ,the propellers hitherto practically applied in steam navigation are the paddle-wheel and the screw4 ,the experience of modern steam navigation points to the exclusive use and advantage of the screw propeller where great speed of shaft is obtainable1 and the electric engine is pre-eminently a high-speed engine1 consequently the screw appears to be most suitable to the requirements of electric boats4 ,by simply fixing the propeller to the prolonged motor shaft1 we complete the whole system1 which1 when correctly made1 will do its duty in perfect order1 with an efficiency approaching theory to a high degree4 ,illustration3 ,,fig4 #a4--,,reckenzaun',s ,,electrical ,,horse ,,power ,,diagram4 ,draw a square1 ,a ,b ,c ,d--divide ,b ,c into #gdf parts1 and ,c ,d into #a1jjj parts1 or1 generally1 let a division on ,c ,d be #j4gdf of a division on ,b ,c1 so that we can use the horizontal lines cutting ,a ,b as a horse power scale4 ,a ,b1 in the above diagram1 gives #a1jjj horse power1 if the line ,b ,c represents #gdf volts1 and ,c ,d #a1jjj amperes4 ,let x any number of volts1 y the amperes1 and h the horse power1 then h_/x y_/#ajj 34 h xy_/#gdf ,a fine wire or thread stretched from o as a center to the required division on ,c ,d will facilitate references4 ,whatever force may be imparted to the water by a propeller1 such force can be resolved into two elements1 one of which is parallel1 and the other in a plane at right angles to the keel4 ,the parallel force alone has the propelling effect2 the screw1 therefore1 should always be so constructed that its surfaces shall be chiefly employed in driving the water in a direction parallel to the keel from stem to stern4 ,illustration3 ,fig4 #b--,,kapp',s ,,diagram4 ,it is evident that a finely pitched screw1 running at a high velocity1 will supply these conditions best4 ,with that beautiful screw lying on this table1 and made by ,messrs4 ,yarrow1 #ie per cent4 of efficiency has been obtained when running at a speed of over #hjj revolutions per minute--that is to say1 only #e per cent was lost in slip4 ,reviewing the various points of advantage1 it appears that electricity will1 in time to come1 be largely used for propelling launches1 and1 perhaps1 something more than launches4 ,in conclusion1 quoting ,dr4 ,lardner's remarks on the subject of steam navigation of nearly fifty years ago1 he said3 ,some1 who1 being conversant with the actual conditions of steam engineering as applied to navigation1 and aware of various commercial conditions which must affect the problem1 were enabled to estimate calmly and dispassionately the difficulties and drawbacks1 as well as the disadvantages1 of the undertaking1 entertained doubts which clouded the brightness of their hopes1 and warned the commercial world against the indulgence of too sanguine anticipation of the immediate and unqualified realization of the project4 ,they counseled caution and reserve against an improvident investment of extensive capital in schemes which still be only regarded as experimental1 and which might prove its grave4 ,but the voice of remonstrance was drowned amid the enthusiasm excited by the promise of an immediate practical realization of a scheme so grand4 ,it cannot1 he continues1 be seriously imagined that any one who had been conversant with the past history of steam navigation could entertain the least doubt of the abstract practicability of a steam vessel making the voyage between ,bristol and ,new ,york4 ,a steam vessel1 having as cargo a couple of hundred tons of coals1 would1 cteris paribus1 be as capable of crossing the ,atlantic as a vessel transporting the same weight of any other cargo4 ,dr4 ,lardner is generally credited with having asserted that a steam voyage across the ,atlantic was a physical impossibility1 but in the work from which ,i took the liberty of copying his words he denies the charge1 and says that what he did affirm was1 that long sea voyages could not at that time be maintained with that regularity and certainty which are indispensable to commercial success1 by any revenue which could be expected from traffic alone4 ,the practical results are well known to us4 ,history repeats itself1 and the next generation may put on record our week attempts1 our doubts and fears of this day4 ,whether electricity will ever rival steam1 remains yet to be proved2 we may be on the threshold of great things4 ,the premature enthusiasm has subsided1 and we enter upon the road of steady progress4 ,mr4 ,wm4 ,h4 ,preece1 the chairman1 in inviting discussion1 said that no doubt those present would like to know something about the cost of such a boat as ,mr4 ,reckenzaun described1 and he hoped that gentleman would give them some information on that point4 ,admiral ,selwyn thought ,mr4 ,reckenzaun was a little below the mark when he talked about the dream of getting #e horse power for one pound--he would not say of coal1 but of fuel4 ,for some months he had seen lb4 of fuel produce #a horse power1 and he knew it could be done4 ,that fuel was condensed concentrated fuel in the shape of oil4 ,when this could be done1 electrical energy also could be obtained much cheaper1 but if it were extended to yachts1 he thought that would be as far as any one now present could be expected to see it go4 ,still he thought there was a future for it1 and that future would be best advanced by considering the question on which he had touched4 ,first1 the employment of a cheaper mode of getting the power in the steam engine2 and1 secondly1 a cheaper and higher secondary battery4 ,in a railway train weight was a formidable affair1 but in a floating vessel it was still more important4 ,he did not think1 however1 that a light secondary battery was by any means an impossibility4 ,mr4 ,loftus ,perkins had actually produced by improvements in the boiler and steam engine two great things3 first1 one indicated horse power for a pound of fuel per hour1 and next he had devised a steam engine of #ajj horse power1 of a weight of only #hd lb4 per horse power1 instead of #cjd lb41 which was about the average4 ,those were two enormous steps in advance1 and under a still more improved patent law he had no doubt things would be brought forward which would show a still greater progress4 ,within the last fifteen days1 nearly #b1jjj patents had been taken out1 as against #e1jjj in the whole of the previous year1 which showed how operative a very small and illusory inducement had been to encourage invention4 ,he had long been known as an advocate of patent law reform1 and1 therefore1 felt bound to lose no opportunity of calling attention to its importance4 ,invention was in the hands of the inventor1 the creator of trade4 ,if1 without robbing anybody1 one wished to produce property1 it must be done by improving manufactures as a consequence of inventions4 ,in one instance alone it bad been proved that a single invention had been the means of introducing twenty millions annually1 upon which income tax was paid4 ,mr4 ,crampton said he did not think steam could ever compete with electricity1 under certain circumstances2 but1 at the same time1 it would be a long time before it was superseded4 ,he should like very much to see the compressed oil1 one-sixth of a pound of which would give #a horse power per hour4 ,admiral ,selwyn said he had seen a common ,cornish boiler doing it years ago4 ,mr4 ,crampton said it had never come under his notice1 and he had no hesitation in saying that no such duty ever was performed by any oil1 because he never heard of any oil which evaporated more than eighteen to twenty-two pounds of water per pound4 ,however1 he was delighted to hear of such progress being made1 and though he had been for so many years connected with steam1 he never expected it would last forever4 ,he was now making experiments for some large shipowners1 for the purpose of facilitating feeding and doing away with dust1 but let him succeed to what extent he might1 steam would never compete with electricity for such small vessels as these launches4 ,the ,chairman asked if he rightly understood ,admiral ,selwyn that he had recently seen an invention in which one-sixth of a pound of condensed fuel would give #a horse power per hour4 ,admiral ,selwyn said it was now some years ago since he saw this going on1 but the persons who did it did not know how or why it was done4 ,he had studied the question for the last ten years1 and now knew the rationale of it1 and would be prepared shortly to publish it4 ,he knew that #bb was the theoretical calorific value of the pound of oil1 and never supposed that oil alone would give #df lb41 which he saw it doing4 ,he had found out that by means of the oil forming carbon constantly in the furnace1 the hydrogen of the steam was burned1 and that it was a fallacy to suppose that an equal quantity of heat was used in raising steam1 at a pressure of1 say1 #abj lb4 to the square inch1 as the hydrogen was capable of developing when properly burned4 ,there were1 however1 conditions under which alone that combustion could take place--one being that the heat of the chamber must be #c1gjj1 and that carbon must be constantly formed4 ,mr4 ,gumpel said with regard to the general application of electricity to the propulsion of vessels as well as to railway trains1 he believed that many of those present would live to see electricity applied to that purpose1 because there were so many minds now applied to the problem1 that before long he had no doubt we should see coal burned in batteries1 as it was now burned in steam boilers4 ,the utmost they could do1 then1 would be about #ej per cent4 less than ,admiral ,selwyn said could be accomplished with condensed fuel4 ,he could not but wonder where ,admiral ,selwyn obtained his information1 knowing that a theoretically perfect heat engine would only give #bc per cent4 of the absolute heat used1 and that a pound of the best coal would give but #h1jjj and hydrocarbon #ac1jjj heat units1 while hydrogen would give #cd1jjj2 and calculating it out1 how was it possible to get out of one-sixth of a pound of carbon1 or any hydrocarbon1 the amount of power stated8 ,no doubt1 when ,admiral ,selwyn applied the knowledge which physicists would give him of the amount of power which could be got out of a certain amount of carbon and hydrogen1 he would find that there was a mistake somewhere4 ,mr4 ,reckenzaun1 in reply1 said it would be very difficult to answer the question put by the ,chairman1 as to the cost of an electric launch--quite as difficult as to say what would be the cost of a steam launch4 ,it depended on the fittings1 the ornamental part1 the power required1 and the time it was required to run4 ,if such a launch were to run constantly1 two sets of accumulators would be required1 one to replace the other when discharged4 ,this could be easily done1 the floor being made to take up1 and the cells could be changed in a few minutes with proper appliances4 ,as to ,admiral ,selwyn's remarks about one-sixth of a pound of fuel per horse power1 he had never heard of such a thing before1 and should like to know more about it4 ,mr4 ,loftus ,perkins' new steam engine was a wonderful example of modern engineering4 ,a comparatively small engine1 occupying no more space than that of a steam launch of considerable dimensions1 developed #hjj horse power indicated4 ,from a mechanical point of view1 this engine was extremely interesting2 it had four cylinders1 but only one crank and one connecting rod2 and there were no dead centers4 ,the mechanism was very beautiful1 but would require elaborate diagrams to explain4 ,mr4 ,perkins deserved the greatest praise for it1 for in it he had reduced both the weight of the engine and the consumption of fuel to a minimum4 ,he believed he used coke and took one pound per horse power4 ,he should not like to cross the ,channel in the electric launch1 if there was a heavy sea on1 for shaking certainly did not increase the efficiency of the accumulators1 but a fair amount of motion they could stand1 and they had run on the ,thames1 by the side of heavy tug boats causing a considerable amount of swell1 without any mishap4 ,of course each box was provided with a lid1 and the plates were so closely packed that a fair amount of shaking would not affect them2 the only danger was the spilling of the acid4 ,mr4 ,crohne had remarked that a torpedo boat of that size would have #ajj indicated horse power1 but then the whole boat would be filled with machinery4 ,what might be done with electricity they had1 as yet1 no idea of4 ,at present1 they could only get #cc1jjj foot pounds from #a lb4 of lead and acid1 though1 theoretically1 they ought to get #cfj1jjj foot pounds4 ,iron in its oxidation would manifest theoretically #a1ijj1jjj foot pounds per lb4 of material4 ,as yet they had not succeeded in making an iron accumulator2 if they could1 they would get about six or seven times the energy for the same weight of material1 or could reduce the weight proportionately for the same power1 and in that way they might eventually get #gj horse power in a boat of that size1 because the weight of the motor was not great4 ,with regard to the formation of a film on the surface1 no doubt a film of sulphate of lead was formed if the battery stood idle1 but it did not considerably reduce its efficiency2 as soon as it was broke through by the energy being evolved from it1 it would give off its maximum current4 ,they knew by experience that1 with properly constructed accumulators1 #hj per cent4 of the energy put into them was returned in work4 ,it was quite certain1 as ,mr4 ,crampton said1 that it would be a long time before steam was superseded3 he did not prophesy at all2 and he entitled his paper ,electric ,launches1 because it would be presumptuous to speak of anything more until larger vessels had been made and tried4 ,with regard to ,mr4 ,gumpel's remark on the friction of the propeller1 he would say that it was constructed to run #ijj revolutions2 if it were driven by a steam engine1 and the speed reduced to #cjj1 not only would the pitch have to be altered1 but the surface would have to be larger1 which would entail more friction4 ,mr4 ,crohne would bear him out that they lost only #e per cent4 by slip and friction combined1 on an average of a great number of trials1 both with and against the current4 ,the ,chairman in proposing a vote of thanks to ,mr4 ,reckenzaun1 said he rejoiced to find that that gentleman had proved1 to one man at least1 that his views had been mistaken4 ,he found in these days of the practical applications of electricity1 that the ideas of most practical men were gradually being proved to be mistaken1 and every day new facts were being discovered1 which led them to imagine that as yet they were only on the shore of an enormous ocean of knowledge4 ,it was quite impossible to say what these electric launches would lead to4 ,certain points of great importance had been pointed out2 they gave great room and they were always ready4 ,for lifeboat and fire engine purposes1 as ,captain ,shaw pointed out at ,vienna1 this was of great consequence4 ,at first they were led to believe that there was great stability1 but that idea had been a little shaken1 not as to the boat itself1 but as to the influence of the motion of the water upon the constancy of the cells4 ,but these boats were only intended for smooth water1 and if they could not be adapted for rough water1 he feared ,admiral ,selwyn's suggestion of the application of this principle to lifeboats would fall to the ground2 but if secondary batteries were not calculated as yet to stand rough usage1 it only required probably some thought on ,mr4 ,reckenzaun's part to make them available even in a gale4 ,enormous strides were being made with regard to these batteries4 ,no one present had been a greater skeptic with regard to them at first than be himself2 but after constant experiments--employing them1 as he had done for many months1 for telegraphic purposes--he was gradually coming to view them with a much more favorable eye4 ,the same steps which had rendered all scientific notions practicable1 had gradually eliminated the faults which originally existed1 and they were now becoming good1 sound1 available instruments4 ,at present1 he could only regard this electric launch as a luxury4 ,he had hoped that ,mr4 ,reckenzaun would have been able to say something which would have enabled poor men to look forward to the time when they might enjoy themselves in them on the river2 but he was told at ,vienna1 when he enjoyed two or three trips in this boat on the ,danube1 that her cost would be about #hjj1 which was a little too much for most people4 ,they wanted something more within their reach1 so that at various points on the river they might see small engines constantly at work supplying energy to secondary batteries1 and so that they might start on a ,friday evening1 and go up as far as ,oxford1 or higher1 and come down again on ,monday morning4 ,he must congratulate ,mr4 ,reckenzaun on the excellent diagrams he had constructed4 ,the trouble of calculating figures of this sort was very great when making experiments2 and the use of diagrams and curves expedited the labor very much4 ,at present they were passing through a stage of electrical depression2 robbery had been committed on a large scale2 the earnings of the poor had been filched out of their pockets by sanguine company promotors2 an enormous amount of money had been lost1 and the result had been that confidence was1 to a great extent1 destroyed2 but those who had been wise enough to keep their money in their pockets1 and to read the papers read in that room1 must have seen that there was a constant steady advance in scientific knowledge of the laws of electricity and in their practical applications1 and as soon as some of these rotten1 mushroom companies had been wiped out of existence1 they might hope that real practical progress would be made1 and that the day was not far distant when the public would again acquire confidence in electrical enterprise4 ,they would then enable inventors and practical men to carry out their experiments1 and to put electrical matters on a proper footing4 99 99 99 99 99 ,,the ,,first ,,experiments ,,with ,,the ,,electric ,,light4 ,electric lighting dates back1 as well known2 to the celebrated experiment of ,sir ,humphry ,davy1 which took place in #ahji or #ahaj1 but the date of which is often given as #ahac4 ,there exist however1 some indications that experiments on the production of the electric spark between carbons had been performed before the above named date4 ,mr4 ,s4,p4 ,thompson has given the following interesting details in regard to this subject3 ,in looking over an old volume of the ,journal de ,paris1 says he1 ,i found under date of the #bb;d ,ventose1 year ,x4 7,march #ab1 #ahjb71 the following passage1 which evidently refers to an exhibition of the electric arc3 ,citizen ,robertson1 the inventor of the phantasmagoria 7magic lantern71 is at present performing some interesting experiments that must doubtless advance our knowledge concerning galvanism4 ,he has just mounted metallic piles to the number of #b1ejj zinc plates and as many of rosette copper4 ,we shall forthwith speak of his results1 as well as of a new experiment that he performed yesterday with two glowing carbons4 ,illustration3 ,,sir ,,humphry ,,davy',s ,,electric ,,light ,,experiments ,,in #ahac4 ,the first having been placed at the base of a column of #abj zinc and silver elements1 and the second communicating with the apex of the pile1 they gave at the moment they were united a brilliant spark of an extreme whiteness that was seen by the entire society4 ,citizen ,robertson will repeat this experiment on the #beth4 ,the date generally given for the invention of the electric light by ,sir ,humphry ,davy is #ahji1 but previous mentions of his experiment are found in ,cuthberson's ,electricity 7#ahjg7 and in other works4 ,in the ,philosophical ,magazine1 vol4 ix41 p4 #bai1 under date of ,feb4 #a1 #ahja1 in a memoir by ,mr4 ,h4 ,moyes1 of ,edinburgh1 relative to experiments made with the pile1 we find the following passage3 ,when the column in question had reached the height of its power1 its sparks were seen by daylight1 even when they were made to jump with a piece of carbon held in the hand4 ,illustration3 ,,electric ,,lighting ,,in ,,paris ,,in #ahdd4 ,in the ,journal of the ,royal ,institution1 vol4 i4 7#ahjb71 ,davy describes 7p4 #ajf7 a few experiments made with the pile1 and says3 ,when1 instead of metals1 pieces of well calcined carbon were employed1 the spark was still larger and of a clear white4 ,on page #bad he describes and figures an apparatus for taking the galvano-electric spark into fluid and aeriform substances4 ,this apparatus consisted of a glass tube open at the top1 and having at the side a tube through which passed a wire that terminated in a carbon4 ,another wire1 likewise terminating in carbon1 traversed the bottom and was cemented in a vertical position4 ,but all these indications are posterior to a letter printed in ,nicholson's ,journal1 in ,october1 #ahjj1 p4 #aej1 and entitled3 ,additional ,experiments on ,galvanic ,electricity in a ,letter to ,mr4 ,nicholson4 ,the letter is dated ,dowry ,square1 ,hotwells1 ,september #bb1 #ahjj1 and is signed by ,humphry ,davy1 who at this epoch was assistant to ,dr4 ,beddoes at the ,philosophical ,institution of ,bristol4 ,it begins thus3 ,sir3 ,the first experimenters in animal electricity remarked the property that well calcined carbon has of conducting ordinary galvanic action4 ,i have found that this substance possesses the same properties as metallic bodies for the production of the spark1 when it is used for establishing a communication between the extremities of ,signor ,volta's pile4 ,in none of these extracts1 however1 do we find anything that has reference to the properties of the arc as a continuous1 luminous spark4 ,it was in his subsequent researches that ,davy made known its properties4 ,it will be seen1 however1 that the electric light had attracted attention before its special property of continuity had been observed4 ,it results from these facts that ,robertson's experiment was in no wise anterior to that of ,davy4 ,the inventor of the phantasmagoria did not obtain the arc1 properly so called1 with its characteristic continuity1 but merely produced a spark between two carbons--an experiment that had already been made known by ,davy in #ahjj4 ,the latter had then at his disposal nothing but a relatively weak pile1 and it is very natural that1 under such circumstances1 he produced a spark without observing its properties as a light producer4 ,it was only in #ahjh that he was in a position to operate upon a larger scale4 ,at this epoch a group of men who were interested in the progress of science subscribed the necessary funds for the construction of a large battery designed for the laboratory of the ,royal ,institution4 ,this pile was composed of #b1jjj elements mounted in two hundred porcelain troughs1 one of which is still to be seen at the ,royal ,institution4 ,the zinc plates of these elements were each of them #cb inches square1 and formed altogether a surface of #hj square meters4 ,it was with this powerful battery that ,davy1 in #ahaj1 performed the experiment on the voltaic arc before the members of the ,royal ,institution4 ,the carbons employed were rods of charcoal1 and were rapidly used up in burning in the air4 ,so in order to give longer duration to his experiment1 ,davy was obliged1 on repeating it1 to inclose the carbons in a glass globe like that used in the apparatus called the electric egg4 ,the accompanying figure represents the experiment made under this form in the great ampitheater of the ,royal ,institution at ,london4--,la ,lumiere ,electrique4 99 99 99 99 99 ,,electrical ,,grapnel ,,for ,,submarine ,,cables ,,and ,,torpedo ,,lines4 ,by ,h4 ,,kingsford4 ,all those who are acquainted with the cable-lifting branch of submarine telegraphy are well aware how important a matter it is in grappling to be certain of the instant the cable is hooked4 ,this importance increases1 of course1 with the age and consequent weakness of the material1 as the injury caused by dragging a cable along the bottom is obviously very great4 ,illustration3 ,,electrical ,,grapnel ,,for ,,submarine ,,cables ,,and ,,torpedo ,,lines4 ,it is easy also to understand the fact that in nearly all cases the most delicate dynamometers must fail to indicate immediately the presence of the cable on the grapnel1 more especially in those cases where a considerable amount of slack grapnel rope is paid out4 ,in many cases1 therefore1 the grapnel will travel through a cable without the slightest indication 7or at least reliable indication7 occurring on the dynamometer1 and perhaps several miles beyond the line of cable will be dragged over1 either fruitlessly1 or to the peril of neighboring cables2 whereas1 should the engineer be advised of the cable's presence on the grapnel1 the break will probably be avoided and the cable lifted2 at any rate1 the position of the cable will be an assured thing4 ,my own knowledge of cable grappling has convinced me of these facts2 and ,i am well assured that those engineers at least who have been engaged in grappling for cables in great depths1 or for weak cables in shallow water1 will heartily agree with me4 ,in addition to the foregoing remarks re the insufficiency of the dynamometer as an instrument for indicating the presence of a cable on the grapnel1 ,i might remind engineers of the troubles and perplexities which occur incessantly in dragging over a rocky bottom4 ,the grapnel hooks a rock1 a large increase of strain is indicated on the dynamometer1 and it becomes doubtful whether the cable as well is hooked or not4 ,again1 it frequently happens in grappling over a rocky bottom that one or more prongs are broken off1 the grapnel thus becoming useless1 great waste of time being thus occasioned4 ,fully realizing all the difficulties herein enumerated1 it occurred to me that a grapnel might be constructed in such a manner as to automatically signal by electrical means the hooking of the cable1 while it would ignore all strain that external causes might bring to bear on it1 and thereby obviate the uncertainties attached to the use of the grapnels at present in vogue4 ,to effect this1 ,i designed early in #ahha a grapnel fitted in each prong with an insulated conducting surface1 and a plunger and pin so arranged that the cable1 when hooked1 should1 by the pressure that it would bring to bear on any of the plungers1 cause the pin to come in contact with the conducting surface1 itself in electrical communication with any suitable current detecter and battery on board the repairing ship1 and thereby complete the circuit4 ,this grapnel was successfully used on the ,anglo-,american ,telegraph ,company's repairing steamer ,minia in the summer of #ahha4 ,subsequently1 in discussing the construction of the grapnel with ,captain ,troot1 we concluded that something was yet wanted to render the successful working in deep water absolutely sure1 and we decided1 consequently1 to make certain alterations4 ,this improved form may be constructed1 either with a contact-plate in each prong1 or with one contact-plate common to all the prongs2 the latter is somewhat simpler1 and is therefore the plan that we usually adopt4 ,both forms are shown in the accompanying diagrams4 ,the form of grapnel in ,diagram ,no4 #a has one advantage over the other in this respect1 viz41 that should a prong be ruptured so as to render it useless1 the fact would immediately be known on board4 ,a circuit formed in such a manner1 by the breaking off of a branch lead1 would have greater resistance than that formed by the contact resulting from pressure of cable on the plungers2 this difference would be manifested on the indicator 7of low resistance7 placed in circuit with the alarm-bell1 or1 if any doubt remained1 a ,wheatstone's bridge1 or simpler still1 a telephone might be made use of4 ,in some cases we may protect the plungers from the pressure of ooze1 etc41 by guards fitted to the stem of the grapnel1 but in practice we have not found these to be necessary4 ,the water is allowed free access around and about each separate part1 in order that its pressure shall be equal on all sides4 ,this arrangement renders the grapnel as effectual in the deepest as in the shallowest water4 ,by making the plungers in two pieces1 with a rubber washer or its equivalent between them1 we prevent mud or ooze from getting behind and interfering with their working4 ,as the hole in the rubber surrounding the contact-plate1 by caused the passage of the pin through it1 closes up as soon as the pressure is removed1 leaving in the rubber a fault of exceedingly high resistance1 the rubber does not require renewing4 ,in the rubber in which we embedded the contact-plate1 we place a layer or more of tinfoil or other easily pierced conducting surface1 through which the pin passes on its way to the contact-plate proper4 ,this method we have adopted in order to make the assurance of contact doubly sure4 ,the grapnel just described we had in use on the ,minia since ,april last4 ,we have tried it severely1 and have never known it to fail4 ,no swivel has been used with the rope1 in the heart of which is the insulated wire1 as it would allow the grapnel to turn over on the bottom1 and would be apt to twist and break the wire short off4 ,as a matter of fact1 the grapnel will turn1 and does turn1 with the rope2 a swivel is therefore of no value4 ,we are perfectly awake1 however1 to the fact that a grappling-rope should be made in a manner that will not allow it to kink2 and engineers should avail themselves of such rope1 especially in deep water4 ,patents have lately been granted to ,messrs4 ,trott ,hamilton for the invention of a form of rope or cable answering all the requirements of this work4 ,a small type of grapnel fitted in the manner ,i have described may be very advantageously used for searching purposes1 to ascertain the position either of telegraph or torpedo lines2 by towing at a quick rate much time may be saved4 ,the position being ascertained1 if it be not desired to lift the cable1 the grapnel can be released and hove on board by a tripping line1 which can always be attached when such work is contemplated4 ,the great importance of being able to localize an enemy's torpedo lines without raising an alarm will be readily seen by engineers engaged in torpedo work4 ,,references ,,to ,,the ,,diagrams4 a1 stem of the grapnel containing core2 b1 flukes2 c1 recess for insulated contact-plate connected to core2 d1 covering plate screwed on bottom of grapnel2 e1 button of plug2 f1 rubber washer and button2 g1 metal-plate2 h1 stem of plug1 on which in the under counter-sink1 ,u is a small metal disk which prevents the fittings from fallings out2 i1 needle2 j1 spring2 k1 counter-sink for head of plug2 l1 counter-sink for spring4 99 99 99 99 99 ,,hughes' ,,new ,,magnetic ,,balance4 ,a new magnetic balance has been described before the ,royal ,society by ,prof4 ,d4 ,e4 ,hughes1 ,f4,r4,s41 which he has devised in the course of carrying out his researches on the differences between different kinds of iron and steel4 ,the instrument is thus described in the ,proceedings of the ,royal ,society3 ,it consists of a delicate silk-fiber-suspended magnetic needle1 #e cm4 in length1 its pointer resting near an index having a single fine black line or mark for its zero1 the movement of the needle on the other side of zero being limited to #e mm4 by means of two ivory stops or projections4 ,illustration ,when the north end of the needle and its index zero are north1 the needle rests at its index zero1 but the slightest external influence1 such as a piece of iron #a mm4 in diameter #aj cm4 distant1 deflects the needle to the right or left according to the polarity of its magnetism1 and with a force proportional to its power4 ,if we place on the opposite side of the needle at the same distance a wire possessing similar polarity and force1 the two are equal1 and the needle returns to zero2 and if we know the magnetic value required to produce a balance1 we know the value of both4 ,in order to balance any wire or piece of iron placed in a position east and west1 a magnetic compensator is used1 consisting of a powerful bar magnet free to revolve upon a central pivot placed at a distance of #cj or more cm41 so as to be able to obtain delicate observations4 ,this turns upon an index1 the degrees of which are marked for equal degrees of magnetic action upon the needle4 ,a coil of insulated wire1 through which a feeble electric current is passing1 magnetizes the piece of iron under observation1 but1 as the coil itself would act upon the needle1 this is balanced by an equal and opposing coil on the opposite side1 and we are thus enabled to observe the magnetism due to the iron alone4 ,a reversing key1 resistance coils1 and a ,daniell cell are required4 ,the general design of the instrument1 as shown in a somewhat crude form when first exhibited1 is given in the figure1 where ,a is the magnetizing coil within which the sample of iron or steel wire to be tested is placed1 ,b the suspended needle1 ,c the compensating coil1 and ,m the magnet used as a compensator1 having a scale beneath it divided into quarter degrees4 ,the idea of employing a magnet as compensator in a magnetic balance is not new1 this disposition having been used by ,prof4 ,von ,feilitzsch in #ahef in his researches on the magnetizing influence of the current4 ,in ,von ,feilitzsch's balance1 however1 the compensating magnet was placed end on to the needle1 and its directive action was diminished at will1 not by turning it round on its center1 but by shifting it to a greater distance along a linear scale below it4 ,the form now given by ,hughes to the balance is one of so great compactness and convenience that it will probably prove a most acceptable addition to the resources of the physical laboratory4--,nature4 99 99 99 99 99 ,,how ,,to ,,harden ,,cast ,,iron4 ,cast iron may be hardened as follows3 ,heat the iron to a cherry red1 then sprinkle on it cyanide of potassium and heat to a little above red1 then dip4 ,the end of a rod that had been treated in this way could not be cut with a file4 ,upon breaking off a piece about one-half an inch long1 it was found that the hardening had penetrated to the interior1 upon which the file made no more impression than upon the surface4 ,the same salt may be used to caseharden wrought iron4 99 99 99 99 99 ,,apparatus ,,for ,,measuring ,,small ,,resistances4 ,the accompanying engraving shows a form of ,thomson's double bridge1 as modified by ,kirchhoff and ,hausemann4 ,the chief advantage claimed for this instrument consists in the fact that all resistances of defective contact between the piece to be measured and the battery are entirely eliminated--an object of prime importance in measuring very small resistances4 ,by the use of this instrument resistances can be measured accurately down to one-millionth of a ,siemens unit4 ,the general arrangement of the instrument is shown in ,fig4 #a2 ,fig4 #b being a diagram of the electrical connections4 ,illustration3 ,,fig4 #a4--,,kirchhoff ,,and ,,hansemann',s ,,bridge ,,for ,,measuring ,,small ,,resistances4 ,the piece of metal to be measured1 ,m1 is placed in the measuring forks1 gg1 in such a manner that the movable fork is removed as far as possible from the stationary one2 if the weight of the piece be insufficient to secure a good connection1 additional weights may be placed upon it4 ,the main circuit includes the battery1 ,b 7,fig4 #b71 consisting of from two to four ,bunsen cells1 the key1 ,t1 the ,german silver measuring wire1 ,n1 and the piece of metal resting on the forks1 all being joined in series4 ,the ,german silver wire1 ,n1 is traversed by two movable knife-edge contacts1 cc1 as shown4 ,connections are made between these contacts1 cc1 the resistance box1 the prongs1 k and l1 of the forks1 gg1 and the reflecting galvanometer1 as shown in ,fig4 #b4 ,a resistance of ten units is inserted at o and n1 while at m and p twenty units or one thousand units are inserted4 ,the positions of cc are then varied until the galvanometer shows no deflection when the key1 ,t1 is depressed4 ,illustration3 ,,fig4 #b4--;,,diagram ,,showing ,,electtrical ,,connections ,,of ,,bridge4 ,when such is the case1 the ratio of resistances n_/m is equal to o_/p2 letting ,m equal the resistance of the metal bar between the points1 h and i1 and ,n equal to the resistance between the points1 cc1 on the measuring wire1 ,n1 then we shall have ,m ,n 7n_/m7 ,n 7o_/p74 ,knowing the cross section in millimeters1 ,q1 of the bar1 and observing the temperature1 t1 in degrees ,centigrade1 its conductivity1 x1 as compared with mercury can be determined4 ,if ,l be the distance1 h l or k i1 in meters1 then x 7#a_/m7 7,l_/,q7 7#a at74 ,for pure metals the value of a may be taken at #j4jjd2 but alloys have a different coefficient4 ,the instrument is made by ,siemens and ,halske1 and is accompanied by a table giving resistances per millimeter of the measuring wire1 ,n4--,zeitsch4 fr ,elektrotechnik4 99 99 99 99 99 ,,terrestrial ,,magnetism4 ,footnote3 ,for a full account of experiments relating to magnetism on railways in ,new ,york city1 see ,,scientific ,,american1 ,january #ai1ahhd4 ,to the ,editor of the ,scientific ,american3 ,an item has appeared recently in several papers1 stating that ,new ,york is a highly magnetized city--that the elevated railroad1 ,brooklyn ,bridge cables1 etc41 are all highly magnetized4 ,as this might convey to the general reader the impression that the magnetism thus exhibited was peculiar to ,new ,york city1 and as many of your subscribers look anxiously for your answers to numerous questions put for the elucidation of apparent1 scientific mysteries1 ,i have thought that perhaps a statement in plain language of experiments made at various times1 to elucidate this subject1 might1 in conjunction with a diagram1 serve to explain even to those who have not made a special study of science a few of the interesting phenomena connected with ,,terrestrial ,,magnetism4 ,some of the first experiments ,i made1 while professor at the ,indiana ,state ,university1 were detailed in the ,march and ,august numbers1 #ahgb1 of the ,journal of the ,franklin ,institute1 and ,i think showed conclusively that the earth1 by induction1 renders all articles of iron1 steel1 or tinned iron magnetic2 possessing for the time being polarity1 after they have been in a settled position for a short time4 ,in ,dr4 ,i4 ,c4 ,draper's ,year ,book of ,nature for #ahgc1 mention is made of the experiments in which ,i found every rail of a ,n4 and ,s4 railroad exhibiting polarity4 ,the same statements were repeated in one of a series of articles sent by me to the ,indianapolis ,daily ,journal1 dated ,jan4 #bj1 #ahgg1 in which ,i used the following language3 ,every article of iron or steel or tinned iron1 by the earth's induction1 becomes magnetic4 ,thus1 if we examine our stoves1 or a doorlock1 or long vertical hinge1 or even a high tin cup1 by holding a delicate magnetic needle in the hand near those objects1 we find the earth has1 by induction1 attracted to the lower end of the stove utensils1 etc41 the opposite magnetism from its own2 and repelled to the upper end of the stove1 etc41 the same magnetism which exists in our northern hemisphere4 ,consequently1 the bottom of the stove1 or of the hinge1 cup1 etc41 will attract the south 7or unmarked end7 of our needle2 while the top of the stove1 etc41 attracts the north1 or marked end of our magnetic needle4 ,if we apply our needle to the ,t rails of a ,n4 and ,s4 railroad1 we not only find that the lower flange of the rail attracts the ,s4 end of our needle1 while the upper flange attracts the ,n4 end of our needle1 but we also find1 where the two rails come nearly together 7say within two inches71 that the ,n4 end of the rail attracts the ,s4 end of our needle1 while the ,s4 end of the rail attracts the ,n4 7or marked7 end of our magnetic needle4 ,illustration3 ,,magnetism ,,on ,,railways4 ,quite recently1 being anxious to see the effect produced on the needle by rails laid ,e4 and ,w41 ,i experimented on some recently laid here2 starting from a ,s4 terminus1 in the town of ,new ,harmony1 and gradually curving northeast1 until the road pursues a due east course to ,evansville4 ,there is1 however1 a branch road of about half a mile1 which starts from the ,wabash ,river1 at a west terminus1 and runs due east to join the other1 near where that main track commences its northeast curve4 ,the results 7more readily understood by an inspection of the diagram7 were as follows3 #a4 ,at the south terminus of the railroad1 the rails on the east side of the track as well as those on the west side attracted at their south ends the marked end of a small magnetic needle1 both at the upper and lower flange2 the usual vertical induction being in this case overcome by the greater lateral induction4 ,whenever1 on progressing north1 the rails were at least about two inches apart1 the upper flange of the north end of any rail would attract the unmarked1 while the south end of its neighbor or any other of the north and south laid rails would attract the marked end4 #b4 ,the same results were obtained from rails laid all around the northeast curve1 and even after they had acquired a due west to east course2 showing that each rail acquired the same magnetic polarity which would be exhibited by any magnetic needle oscillating freely in our northern hemisphere1 dipping also at its north end considerably downward if suspended at its center of gravity4 #c4 ,applying the needle at the west terminus1 a few anomalies were observed2 but1 especially nearer the junction1 the rails all gave the normal result found on the main track4 #d4 ,the wheels of the cars standing on the north and south track followed the same law1 exhibiting both vertical and lateral induction1 so that the lower rims and the forward or north part of the periphery attracted the unmarked end of the needle1 while the upper and rear1 or south portions of the periphery of the wheel attracted the marked end4 #e4 ,the wheels of cars standing on the east and west road exhibited the following modification4 ,the lowest rim of all the wheels1 whether standing on the north rails or on the south rails of said track1 in consequence of vertical induction attracted the unmarked end of the needle1 and the upper rims attracted the marked end of the needle2 but the middle portions of the periphery1 both anterior and posterior1 of the wheels standing on the north rail1 attracted the unmarked end1 while similar middle portions of wheels standing on south rails attracted the marked end2 in consequence of horizontal induction1 the wheels being connected by iron axles1 and thus presenting considerable extension across the track1 viz41 from south to north4 ,magnetite seems to have acquired its polarity in the same manner1 namely by the earth's induction1 when the ore contains a large enough percentage of pure iron4 ,a large specimen 7#f in4 long by #c deep and weighing #e lb47 which ,i obtained from near ,pilot ,knob1 ,missouri1 exhibits polarity1 not only at its lateral ends1 but also vertically1 as the lower surface attracts the unmarked end of a needle1 while the plane1 which evidently occupied the upper surface in its native bed1 attracts the marked end of the needle4 ,iron fences invariably exhibit only the polarity by vertical induction2 so also small buckets1 bells1 etc4 ,but in the case of a bell about #c ft4 in diameter at its base1 and over two feet deep1 tapering to about a foot in diameter at the top1 ,i found that although the top attracted the marked end of the needle1 the bottom attracted the unmarked end of the needle only around the northerly half of the circumference1 while the southern portion of this lower rim attracted the marked end in consequence of lateral induction1 as in ,n4 and ,s4 rails4 ,thus1 upon a comparison of all these facts1 it would appear that1 if the magnetism induced by the earth is due to so-called currents of electricity1 those currents must be underneath the rails1 and must move from west to east1 under the south to north rails1 and from south to north under the west to east laid rails1 as indicated by the arrows in the diagram4 ,this accords perfectly with what we should theoretically expect1 in our northern hemisphere1 if the electricity in the earth's crust is due to thermo-electrical currents from east to west1 namely1 from the more heated to the less heated portion1 on any given latitude1 while the earth revolves from west to east2 as well as also from electrical currents trending from tropical to ,arctic regions4 ,as the network of iron rails spreads from year to year more extensively over our continent1 it will be interesting to observe whether or not any effect is produced1 meteorological1 agricultural1 etc41 by this diffusion of magnetism4 ,it may further interest some of your readers to have attention called to facts indicating ,,synchronous ,,seismology4 ,the year recently closed furnishes interesting corroborative testimony of an apparent law regarding the propagation of earthquake movements most readily along great circles of our globe1 as well as evidence that these seismic movements are frequently transmitted along belts 7approximating to great circles7 coincident sometimes with continental trends1 at other times with fissures which emanate in radii at every #cj1 around the pole of the land hemisphere in ,switzerland1 as described in one of my papers1 read at the ,montreal meeting of the ,a4,a4,a4,s4 ,the terms synchronism or synchronous1 as here used1 are not designed to imply absolute simultaneity 7although that is sometimes the case with disturbances #ahj apart71 but are rather intended to indicate the tendency presented by these phenomena to exhibit this internal activity1 during successive days1 weeks1 or even months1 along a given great circle of the earth1 especially one or more of those connected with the land center2 perhaps most of all along the great circle which forms the prime vertical1 when the center of land is placed at the zenith4 ,in order to test the above1 let us examine the record of the most prominent earthquakes or volcanic eruptions for the year #ahhc4 ,late in ,dec41 #ahhb1 and early in ,feb41 #ahhc1 shocks occurred in ,new ,hampshire2 on ,jan4 #aa1 #ahhc1 also at ,cairo1 ,illinois1 and about the same time at ,paducah1 ,ky42 ,feb4 #bg at ,norwich1 ,conn41 and early in ,feb4 at ,murcia1 ,spain4 ,these1 by examination of any good globe1 will be found on a belt forming one and the same great circle of the earth4 ,late in ,march and during part of ,april the volcano of ,ometeke in ,lake ,nicaragua was active 7after being long dormant72 ,panama1 portions of the ,u4,s4 of ,colombia1 and of ,chili2 also1 in ,may1 ,helena1 ,m4,t42 and1 in ,june1 ,quito 7with ,cotopaxi active7 were all more or less shaken by earthquakes2 and are all found on one belt of a great circle4 ,the principal record for the remainder of the year comprised3 ,an earthquake at ,tabreez in ,north ,persia1 early in ,may1 #ahhc4 ,the awful destruction in ,ischia1 ,july #bi 7with ,vesuvius active74 ,the fearful eruption in the ,straits of ,sunda1 #beth ,aug4 and later4 ,shocks in ,sumatra and at ,guayaquil1 about same date or early in ,sept4 ,shocks at ,dusseldorf1 according to a ,berlin paper of #eth ,sept4 ,shocks at ,santa ,barbara and ,los ,angeles1 early in ,sept4 ,shocks at ,gibraltar and ,anatolia in ,october4 ,shocks at ,malta1 ,trieste1 and ,asia ,minor in ,october4 ,azram shaken late in ,sept41 and great destruction between ,scios and ,smyrna4 ,lastly1 the formation of a new island in the ,aleutian ,archipelago4 ,date of outburst1 early in ,october1 #ahhc4 ,besides these1 there were several other less severe disturbances1 the records of which are chiefly obtained from ,nature1 and which will-be referred to below4 ,if the globe be so placed as to have the land center at the zenith1 the exact position of the new island1 near ,unnok1 will be found under the brazen meridian1 while ,agram1 ,tabreez1 ,sunda1 ,sumatra1 ,quito1 and ,guayaquil are all on the prime vertical4 ,vesuvius and ,hecla were both active early in the year1 and they1 with the ever restless ,stromboli1 are situated on the great circle which forms with the land center at ,mount ,rosa1 the radius running ,s4 #cj ,e41 and which would embrace the chief disturbances up to the middle of the year1 including as we go north ,malta1 ,sicily1 ,rome1 region of the ,po1 ,bologna1 and in the ,western ,continent1 after passing ,hecla1 ,helena in ,montana ,territory1 reaching in ,washington ,territory and ,oregon the belt of it4 ,american volcanoes3 ,mounts ,baker1 ,rainier1 ,st4 ,helens1 ,hood1 and ,shasta4 ,still another seismic belt1 starting from the ever active ,fogo1 and passing through ,teneriffe 7at that time erupted71 would include the regions disturbed in ,oct4 and ,nov41 namely1 ,cadiz1 ,gibraltar1 ,malaga 7,murcia and ,valencia somewhat earlier72 it then traversed the center of land1 caused the earthquakes at ,olmutz in ,moravia1 and even tremors felt at ,irkutsk1 as the seismic war moved along said great circle to the volcanic region of ,s4 ,japan4 ,again1 the belt which covers the meridian of land center 7about #h-aj ,e4 long7 covers also the region of a disturbanced area in ,norway1 as well as that portion of ,algeria1 viz41 ,bona1 in which a mountain #hjj meters high1 ,naiba1 is gradually sinking out of sight4 ,about #ajj geo4 miles ,e4 of ,bona is where ,graham's ,island appeared in the ,mediterranean1 and a few months later disappeared in deep water4 ,another highly seismic belt extends from the volcanoes of ,bourbon1 ,n4 ,madagascar1 and ,abyssinia to ,santoria and the oft disturbed ,scios1 ,smyrna1 and ,anatolia region2 and along the same great circle were shaken ,patra in ,greece on the #adth ,nov41 and ,bosnia on the #aeth2 while shocks had been felt at ,trieste and ,mlhouse about the #aath1 and at ,styria on the #gth1 and disturbances at ,dusseldorf in ,sept4 ,finally1 on the #bhth ,dec4 ,s4 ,hungary 7near the confluence of the ,drave with the ,danube7 was visited by seismic movements along this same great circle1 which passes through the extinct volcanic region of the ,eifel1 the oft shaken ,comrie in ,perthshire1 ,scotland1 the volcanic ,iceland1 our ,national ,park with its thousands of geysers1 the cataclysmic region of ,salt ,lake and the ,wahsatch ,mountains 7so graphically described by the geologists of the ,u4,s4 ,geol4 ,survey71 giving rise in ,sept4 to the earthquakes of ,los ,angeles and ,santa ,barbara1 and finally reaching the volcanic islands of the ,marquesas group4 ,thus the seismic efforts of #ahhc may be seen to have expended their force partly along the great backbone of the ,s4 and ,n4 ,american ,cordillera1 but more especially from the center of land ,e4 and ,w4 along its prime vertical from ,sunda to ,quito1 also southwesterly by the ,e4 coast of ,spain1 as well as due ,s4 through ,algeria1 and ,s4 #cj ,e4 through ,rome1 ,naples1 ,sicily1 etc4 ,finally1 the autumnal catastrophes at and near ,scios1 ,anatolia1 etc41 seem to have been caused by a seismic wave1 propagated along the great circle1 which often agitates ,janina1 and produces earthquakes at ,agram1 where this great circle crosses the prime vertical4 ,,richard ,,owen4 ,new ,harmony1 ,ind41 #bg ,feb41 #ahhd4 99 99 99 99 99 ,,the ,,iron ,,industry ,,in ,,brazil 7,,province ,,of ,,minas ,,geraes47 ,by ,prof4 ,p4 ,,ferrand4 ,up to the present time1 the methods employed in the province of ,minas ,geraes 7,brazil7 for obtaining iron permit of manufacturing it direct from the ore without the intervening process of casting4 ,these methods are two in number3 #a4 ,the method by cadinhes 7crucibles71 which is the simpler and requires but little manipulation1 but permits of the production of but a small quantity of metal at a time4 #b4 ,the ,italian method1 a variation of the ,catalan1 which requires more skill on the part of the workmen and yields more iron than the preceding4 ,as these methods seem to me of interest1 from the standpoint of their simplicity and easy installation1 ,i propose to describe them briefly1 in order to give as faithful and general an aperu as possible of their application4 ,at present ,i shall deal with the first one only1 the one called the method by ,cadinhes4 ,,study ,,of ,,the ,,method ,,by ,,cadinhes4 ,the province of ,minas ,geraes ocupies a vast extent in the empire of ,brazil1 its superficies being about #ijj1jjj square kilometers1 representing nearly a third of the total surface4 ,the population is relatively small and is disseminated throughout a much broken country1 where the means of communication are very few4 ,so it is necessary to succeed in producing what iron is needed by means that are simple and that require but quickly erected works built of such material as may be at hand4 ,the iron ore is found in very great abundance in this region and is very easily mined4 ,in the center of a mass of quartzites that seem lo constitute the upper level of the eruptive grounds of the province1 there are found strata of an ore of iron designated as itabirite--a mixture of oxide of iron and quartz4 ,these strata are of great thickness1 and have numerous outcrops that permit of their being worked by quarrying4 ,these itabirites present themselves under two very distinct aspects and offer a certain difference in their composition4 ,some are essentially friable1 and are called by the vulgar name of jacutingaes4 ,it is this variety 7which is the one most easily mined7 that is principally consumed in the forges4 ,the others1 on the contrary1 are compact4 ,their exploitation is more difficult1 and before putting them into the furnaces it is necessary to submit them to breakage and screening2 so the use of them is more limited4 ,the first variety contains less iron and more gangue1 but1 per contra1 possesses much oxide of manganese4 ,the second1 on the contrary1 is formed almost wholly of oxide of iron with but little gangue and only traces of oxide of manganese4 ,the following are analyses of these two varieties of ore3 ,friable ,ore4 ,fe#b,o#b4444444444444444444444444444444 444 #hd4i ,oxide of manganese444444444444444444444444444 #i4b ,water4444444444444444444444444444444444 444444 #a4i ,quartz444444444444444444444444444444444 444444 #d4a ---- #ajj4a ,compact ,ore4 ,fe#b,o#c and traces of manganese4444444444 #ii4f ,quartz444444444444444444444444444444444 444444 #a4a ---- #ajj4g ,situation of the ,forges4--,a forge is usually placed on the bank of a brook1 or rather of a torrent1 which supplies the fall of water necessary for the motive power by means of a flume about a hundred meters in length4 ,in most cases the forge is surrounded on all sides with a forest which yields the wood necessary for the manufacture of the charcoal1 and is in the vicinity of the iron quarry1 so as to reduce the expense of hauling the ore as much as possible4 ,the neighboring rocks furnish the foundation stones and stones for the furnaces2 the decomposed schist gives the cement and refractory coating1 and the forest provides the wood necessary for the construction of the road1 sheds1 etc4 ,the head of the trip hammer1 the anvils1 and the tools are the only objects that it is necessary to procure1 and even these the master of the forge often manufactures in part1 after beginning production with an incomplete set4 ,illustration3 #g;a ,,fig #a4--;,,four-,,crucible ,,furnace ,,and ,,forge2 7,,plan74 ,general ,arrangement of a ,forge4--,a forge usually consists of one or two furnaces of three or four crucibles 7the one shown in plan in ,fig4 #a has only one four crucible furnace1 ,a72 #a or #b two fire reheating furnaces1 ,b2 #a trip hammer1 ,c1 actuated by a hydraulic wheel1 ,d2 #b tromps which drive the wind1 one of them1 ,e1 into the cadinhes 7crucibles71 and the other1 ,f1 into the reheating furnace2 #b anvils1 ,g and ,h1 placed near the furnace1 for working delicate pieces2 and finally1 the different tools that serve for maneuvering the bloom and finishing the bars4 ,the charcoal is preserved from rain under a shed1 l4 ,the ore1 which is brought in as needed1 is dumped in a pile at ,m1 in the vicinity of the crucibles4 ,the buildings are set back against the mountain1 and the water is led in by a double flume1 ,l and ,n1 made of planks1 and empties on one side into the wheel and into the tromp1 ,f1 and on the other into the tromp1 ,e1 and then runs into a double waste channel1 ,p and ,q1 which carries it to the stream4 ,illustration3 ,,fig #b4--;,,four-,,crucible ,,furnace2 7,,plan74 ,four ,crucible ,furnace 7,fig4 #b74--,the arrangement of a furnace is very simple4 ,it consists of a cube of masonry containing several cylindrical apertures with elliptic bases1 whose large axis is paralleled with the smaller side of the masonry4 ,this form recalls that of a crucible2 and these cavities are1 moreover1 so named4 ,in the front part of each cadinhe there is a rectangular aperture that gives access to the bottom of the crucible and facilitates the removal of the bloom therefrom4 ,at the back part there is a small aperture for the introduction of the tuyere1 and which permits1 besides1 of the nozzle of the latter being easily got at so as to see whether the blast is working properly4 ,the sides of the crucibles are covered with a thin layer of refractory clay1 and their bottoms have a spherical concavity to hold the bloom4 ,the tuyere1 which is fitted to a wooden conduit of square section that runs along the back of the masonry1 is placed in the axis of the cadinhes and enters the masonry at a few centimeters from the bottom in such away that its nozzle comes just flush with the surface of the refractory lining4 ,this arrangement prevents the tuyere from getting befouled by scori during the operation of the furnace and thus interfering with the wind4 ,tromp4--,the tromp which furnishes the necessary wind to the cadinhes consists of a hollow wooden conduit1 a 7,fig4 #c71 of square section1 which enters a chamber1 b1 along a length of #j4a m4 ,this conduit1 which is about #g meters in height1 receives the water from the flume through the intermedium of an ajutage of pyramidal form1 which serves to choke the vein of liquid1 and the extremity of which is at a few centimeters from the conduit in order to facilitate the entrance of the air2 the latter being attracted by an ill defined action that is supposed to be due to its being carried along by the water1 and to a depression produced by choking the flow of the liquid4 ,illustration3 ,,fig4 #c4--,,the ,,tromp4 ,since the air that is sucked in during the operation has constantly same pressure1 there is no valve for regulating the entrance of the water into the vertical conduit4 ,upon issuing from the latter1 the mixture of air and water strikes the surface of the water in the chamber1 b1 and the violence of the shock upon the bottom is deadened by the interposition of a stone4 ,while the water is escaping through a lateral aperture in the chamber1 b1 the air is reaching the tuyeres through a wooden conduit of square section which is fitted to an aperture in the upper part of the chamber4 ,this sorry arrangement1 which obliges the mixture of air and water to penetrate the water at the bottom of the upright conduit1 a1 retards the separation of the two fluids1 and results in damp air being forced into the crucibles4 ,the ,trip ,hammer4--,fig4 #d shows the general arrangement of the apparatus that go to make up the forging mill4 ,the hammer and cam shaft have their axes parallel1 and the latter is placed in the prolongation of the axis of the wheel4 ,the hammer consists of a roughly squared beam1 #d meters in length1 and of #j4be m4 section4 ,the head1 ,a1 consists of a mass of iron weighing #aej kilos1 including the weight of the straps that surround the beam on every side of the piece of iron4 ,the axis of rotation is situated at the other extremity of the beam1 ,b4 ,the cam shaft which serves to maneuver the trip hammer is provided with four cams which lift the beam at a point near the hammer4 ,the length of this shaft 7to the extremity of which is adapted the water wheel7 is #d4ge m41 and its diameter is #j4ej m4 ,the wheel is an overshot one1 #c4be m4 in diameter by #a m4 in width4 ,the water1 which is led to it by a flume1 acts upon it by its weight and impact1 and is retained in the buckets and kept from overshooting the mark by a jacket made of planks4 ,illustration3 ,,fig4 #d4--,,the ,,trip ,,hammer4 ,the anvil upon which the hammer strikes is surrounded by a bed of stones 7quartzites7 derived from the neighboring rocks4 ,it is a mass of iron1 #ge kilogrammes in weight4 ,in order to prevent vibrations in the trip hammer when it is lifted1 and increase the number of blows1 there is established a spring beam1 which is formed of unsquared timber1 which is firmly fastened at one of its extremities1 and which receives at the other end the shock of the hammer head when the latter reaches the end of its upward travel4 ,reheating ,furnace4--,this is a double fire furnace1 like those used in our smithies1 except that the wind1 instead of being forced into it by means of a bellows1 is supplied by a tromp which receives water from the same channel as the wheel4 ,the two furnace tuyeres are arranged exactly like those of the cadinhes1 upon a wooden conduit which starts from the wind chamber 7,fig4 #e74 ,this furnace serves to prevent the cooling of such blooms as are awaiting their turn to be shingled1 and of such bars of finished iron as are being made into tools4 ,,operation ,,of ,,the ,,system4 ,a forge like the one whose plan we give1 may be run with #a workman at the cadinhes1 #a assistant1 #a workman at the hammer2 total1 #c men4 ,furnace4--,the work lasts about twelve hours per day1 and three operations of three to four hours are performed in each cadinhe1 thus making twelve per day4 ,at each operation1 #bb4e kilos4 of ore and #de of charcoal are used4 ,from this there is obtained a bloom of #ae kilos4 ,the operation is performed as follows3 ,while the assistant has gone to put the bloom of the preceding operation under the hammer1 the workman prepares at the bottom of the crucible a bed consisting of a mixture of sand and very fine charcoal1 and then fills the crucible up to its edge with charcoal4 ,at the end of a quarter of an hour1 the fuel being thoroughly aglow1 the workman puts in the first charge of ore in powder 7jacutingue71 about #b kilos1 and covers it with charcoal4 ,starting from this moment1 he goes on charging every five or ten minutes with #a4e to #b kilos of ore1 taking care in doing so to keep the crucible stuffed with charcoal1 which the assistant places in piles around each cadinhe4 ,this lasts about two and one-half hours4 ,at the end of this time he stops putting in charcoal1 and standing upon the masonry1 walks from one cadinhe to another1 carrying a large rod1 in order to study the lay of the bloom4 ,then1 the fire being entirely out1 he scrapes out the bed of sand and charcoal that closes the opening in the bottom of the crucible1 removes the mass of ferruginous scori which forms a hard paste and surrounds the bloom1 and takes this latter out by means of a hook4 ,the workman runs the four cadinhes at once1 this being easily enough done1 since he has neither to bother himself with regulating the wind1 which enters always with the same pressure1 nor with the flow of the scori1 which remain always at the bottom of the crucible4 ,his role consists simply in keeping his fires running properly1 being guided in this by the color of the flame without making an examination in the interior4 ,he draws each of the four blooms out from its bed at the end of the operation1 while the assistant carries the first to the hammer and the three others to the reheating furnace4 ,he afterward cleans out the crucible1 prepares the bed of sand and charcoal1 fills with charcoal1 and then passes to the next1 and so on4 ,illustration3 ,,fig4 #e4--,,reheating ,,furnace4 ,trip ,hammer4--,the workman at the hammer takes the bloom from the hands of the assistant and shingles it under the head4 ,then he begins to give it shape1 bringing it to the state shown at c1 in ,fig4 #g4 ,the assistant then brings him another bloom and takes the one that has been shingled to the reheating furnace1 where he heats but one of its extremities4 ,when the four blooms have been shingled1 the workman takes up the first and begins to draw out one of its extremities1 which he afterward cools in water and uses as a handle for finishing the work1 d4 ,then he reheats the other extremity1 and1 after drawing it out as he did the other1 obtains a bar of finished iron which he doubles1 as shown at e1 to thus deliver to the trade4 ,illustration3 ,,fig4 #f4--;,,cadinhe ,,in ,,operation4 ,one of these bars weighs from #aa to #ab kilogrammes4 ,it will be seen that1 during the course of the work1 the furnace workmen and the hammer workmen have well defined duties to perform2 but it is not the same with the assistant1 who goes from one to the other according to requirements4 ,there are1 however1 some forges in which each of the workmen has an assistant1 since the blooms produced are heavier1 and one assistant would not suffice for the work of the two men4 ,in such a case the assistant at the crucibles carries the blooms to the reheating furnace1 and the assistant at the hammer carries them from thence to the hammer4 ,illustration3 ,,fig4 #g4--,,working ,,the ,,bloom4 ,,elaboration ,,of ,,the ,,ore4 ,we have seen that the workman who has charge of the fire contents himself with putting charcoal and ore alternately into the crucibles1 and that too according to the aspect of the flames1 without making any examination in the interior1 in order to judge whether the work is proceeding well4 ,the bloom forms gradually beneath the nozzle of the tuyere1 in the center of the bed of sand and charcoal1 and is surrounded on every side with an exceedingly pasty mass1 formed of silicates of iron and manganese 7,fig4 #g74 ,it is only at the end of the operation that the workman1 by means of a rod1 causes the burning coal to drop and verifies the proper position of the bloom by breaking the layer of scori that surrounds it4 ,this coating he breaks off1 removes the bloom with a hook1 and agglutinates with his rod the different bubbles that it exhibits1 and the assistant then carries it to the hammer4 ,,setting ,,up ,a ,,forge4--,,selling ,,price ,,of ,,the ,,iron4 ,to set up a forge like the one we have described1 it is necessary to count upon a first cost of about #aj1jjj francs4 ,add to this the cost of #ej hectares of forest to furnish the charcoal that the workmen have to make every day4 ,the cost of this is very variable1 and floats between #b1ejj and #e1jjj francs per #ajj hectares4 ,the cost the ore is only that connected with getting it but and hauling it4 ,manual ,labor4--,the charcoal burners receive #a4be francs per load of #ij kilos1 thus bringing the price of the product 7including cost price of forest7 at #b4d francs per #ajj kilos4 ,the workmen in the furnace are paid at the rate of from #b4ej to #c4ge francs per day4 ,those that work the hammers receive #c4ge francs1 and the assistants #a4be francs4 ,carriage of the ,forged ,iron4--,the iron is carried from the forge to the places of consumption on the backs of mules1 and the cost of carriage is1 on an average1 #j4be franc per #ajj kilos and per kilometer4 ,selling ,price4--,the selling price is very variable1 and depends principally upon the distance of the place where sold from the different forges that surround it4 ,at ,ouro ,preto the price varies between #de and #ej francs per #ajj kilos4 ,the following is a resume of the data which precede3 ,cost of first establishment444444444444444444 #aj1jjj fr4 ,charcoal per kilogramme4444444444444444444444 #b4dj ,furnace men4444 #b4ej to #c4ge ,manual labor per day ,hammer men4444444444444 #c4ge ,assistants4444444444444 #a4be ,carriage of forged iron per kilometric ton44444 #b4ej ,selling price per #ajj kilos4444444444444444 #de to #ej --,le ,genie ,civil4 99 99 99 99 99 ,,the ,,steamer ,,churchill4 ,we give engravings of the ,churchill1 a vessel lately built to the order of ,mr4 ,walter ,peace1 ,london agent to the ,natal ,harbor ,board1 by ,messrs4 ,hall1 ,russell1 and ,co41 ,aberdeen4 ,she was designed by ,mr4 ,j4,f4 ,flannery1 consulting engineer to the ,board1 for special service at ,natal4 ,the ,churchill has been constructed so as to be capable of towing into or out of harbor over the bar in any weather1 of acting as a very powerful fire engine1 of carrying a large amount of fresh water for the use of other ships1 of landing troops from transports which the harbor is too shallow to admit1 of recovering lost anchors and cables1 of which there are a large number off the coast1 and of acting in time of need as a torpedo or coast defense vessel2 she was launched on the #afth ,august1 and is likely to fulfill all these requirements4 ,illustration3 ,,the ,,new ,,steamship ,,churchill4 ,the principal dimensions of the vessel are3 ,length between perpendiculars #aae feet1 breadth1 extreme1 #bb feet1 depth of hold #aa feet1 and maximum draught with full bunkers #g feet #f inches4 ,there are four water-tight iron bulkheads forming five compartments2 the stern is built very full to protect the propellers4 ,accommodation is arranged on deck for the captain aft with two spare berths1 mate and two engineers amidships1 while six white hands will occupy the forward forecastle1 and six ,kaffirs the after one4 ,for towing purposes she is fitted with one main and two skip hooks secured to the main framing2 towing rails are placed aft1 while bitts are put on one each quarter1 will be seen by referring to the deck plan4 ,the vessel is propelled by twin screws #f feet #h inches in diameter and #ac feet #f inches pitch2 these are of cast iron1 have four blades1 and are driven by a double pair of compound inverted direct acting engines 7see ,figs4 #d to #g7 which are capable of developing #fjj indicated horse power1 and whose cylinders are #ai inches and #cd inches in diameter with a stroke of #b feet4 ,the condensers form part of the engine frame1 and have guide faces cast on for the crosshead shoes4 ,they are fitted with gun metal tube-plates1 and each contain #eaf tubes1 #c_/d inch in diameter1 which have an exposed length of #f feet #e inches1 and give a total cooling surface of #fej square feet4 ,the air and circulating pumps are bolted to the back of the condensers1 and are worked by levers from the engine crosshead4 ,each engine has one feed and one bilge pump attached to the air pump1 and worked by the same lever4 ,the plan of the engines shows the pump arrangement very completely4 ,illustration3 ,,engines ,,and ,,boilers ,,of ,,the ,,new ,,steamship ,,churchill4 ,the steam is supplied by two circular return tube boilers1 #i feet #f inches in diameter and #aj feet long1 with two furnaces in each4 ,the boilers1 which are of steel throughout1 except the tubes1 are placed longitudinally1 and are fitted with two pairs of the ,martyn-,roberts patent safety valves4 ,they have one steam dome between them4 ,the total heating surface is #a1gjj square feet1 the total steam space is #ccj cubic feet1 and the working pressure #ajj lb4 per square inch4 ,the fire pump is a ,wilson's ,excelsior1 with #aj inch steam cylinder and #h inch water barrel4 ,this powerful pump is in a special compartment of the fore hold1 and will draw water from the bilge1 sea1 or either hold4 ,a steam windlass and a double-handle winch are on deck as shown4 ,on trial trip the engines of the ,churchill indicated a maximum of #fde4e horse power1 driving the vessel #aj4die knots per hour4 ,the vessel is remarkable for diversity of uses1 for heavy engine power in a small hull1 and for general compactness of arrangement4--,engineering4 99 99 99 99 99 ,,three-,,way ,,tunnels4 ,mr4 ,t4,r4 ,cramton1 who at the ,southampton meeting of the ,british ,association suggested a method of tunneling which1 under certain conditions1 seems of excellent promise1 brought forward a suggestion at ,southport for the construction of three-way tunnels4 ,now1 the undoubted aim of all engineers is economy of construction and the securing of permanent advantages4 ,mr4 ,crampton maintains that the suggested system will give these1 that three tunnels of1 say1 #ag ft4 diameter1 can be constructed cheaper than one of #cj ft4 diameter4 ,after describing ,sir ,j4 ,c4 ,hawkshaw's scheme for the ventilation of long tunnels1 the three-way scheme was discussed4 ,three separate tunnels of #ag ft4 diameter each1 or #bbg ft4 area1 are to be connected by large passages about midway of their length4 ,these passages are without valves2 in fact1 free air passages4 ,between these midway connections and the ends1 say again midway between1 is formed a branch at right angles either above or below with separate openings from the branch into the other tunnels1 such openings being provided with doors or valves quite clear of the main tunnel1 any two of which may be closed1 thus separating at this point the corresponding tunnels from the third4 ,the branch is to be led to any convenient position where the exhustion apparatus can be placed4 ,if two of the tunnels are left open to this branch1 and the third one shut off from it by closing the doors1 the vitiated air will be drawn from the two working tunnels1 through the connecting branch1 while fresh air will be partly sucked down the vertical shafts through their open ends and partly at the center tunnel1 which is supplied by forcing air down the vertical shaft in communication with it1 a stop or door being placed just outside of the bottom of the shaft so as to compel the air to flow to the center of the tunnel4 ,it will be observed that no trains are running in this air tunnel so long as it is so used2 there are similar doors for the working tunnel1 but they are kept open1 unless either of them is required to be made into an air tunnel1 so that the passing trains run no risk of running into the doors4 ,by means of the doors above mentioned1 any one of the three tunnels can be used as a fresh-air tunnel1 in which the men doing the repairs to the road would be clear of the traffic1 while the other two are used for the traffic1 as well as outlets for the mixed impure gas and air4 ,if a breakdown of a train occurs in any one tunnel1 that tunnel can at once be converted into a fresh-air one1 while its traffic is transferred to the one previously used for air1 thereby avoiding delay4 ,the system described for splitting the air and drawing off the noxious gases is very similar to that described by ,mr4 ,hawkshaw at ,southampton4 ,the valves and other details being added1 to make the system applicable to three tunnels1 it will be obvious that other modes of ventilation may be adopted4 ,in order to reduce the number of men working in the tunnel it is proposed1 if found practicable1 not to adopt the ordinary ballast and cross sleepers1 but to substitute the longitudinal timber system1 the timbers to be secured to brickwork or concrete1 forming a part of the tunnel lining1 placing efficient elastic material between the foundation and longitudinals for their whole area1 also between the rails and sleepers4 ,an open drain is formed between the rails2 by this plan any water accumulating flows over smooth surfaces through small channels into a drain1 the tunnel on each side being dry4 ,the saving of labor in repairs1 if this system can be employed1 is so evident that a large amount of money might be expended in endeavoring to discover a suitable elastic material for the purpose4 ,there are data on many long viaducts sufficient to justify experiments being made on the subject1 and it is not unreasonable to expect that suitable material may be met with4 ,in very long tunnels nothing should be omitted tending to reduce the number of men working in them4 ,the opinion was expressed that in tunnels passing through solid materials1 and proper foundations being made for the longitudinals to rest upon1 with good elastic material placed between the rails and sleepers and foundations1 one-half of the men employed on the ordinary cross sleeper road resting on ballast would be saved1 more particularly as the repairs are effected in pure air free from the traffic as explained4 ,the estimate as to the cost of this system was upon the dimensions given by ,sir ,j4 ,hawkshaw1 and the following gives the comparison3 ,the quantity of excavation and brickwork or concrete in each case will be as follows3 ,single tunnel3 #cj ft4 diameter lining1 #c ft4 thick1 with the brickwork forming the air passage to #cf4e cubic yards per yard forward4 ,excavation to outside of brickwork #cf ft4 diameter to #aac cubic yards per yard forward4 ,three tunnels #ag ft4 diameter and #ah in4 brickwork4 ,brickwork lining for three tunnels #bd4e cubic yards per yard forward4 ,excavation outside brickwork for the same #aje cubic yards per yard forward4 ,it is assumed that three #ag ft4 tunnels are stronger1 more conveniently formed1 and involve less risks in construction than one of #cj ft4 diameter2 at the same time there is no difficulty in making the latter4 ,the above shows the saving in the three tunnels of #bc per cent4 in brickwork1 and about #g per cent4 of earthwork1 compared with one of #cj ft4 ,with regard to ventilation1 it is well known that the power required to force air along passages is practically as the cube of the velocity2 and as the area of the air passages in the single tunnel is #ajf ft4 with speed ten miles per hour1 and that of one of the #ag ft4 diameter is #bbg ft41 or rather more than double1 giving only five miles per hour velocity1 it follows that the power for this portion would be eight times less4 ,that for the working tunnels would be practically the same1 the velocities being nearly alike in both cases1 which would be about #b miles per hour--the #cj ft4 having an area of #dgj ft41 the two single ones together about #dej ft4 ,upon the face of it the system deserves a trial4 ,a full consideration of the scheme by engineers preparing plans for new tunnels would no doubt throw further light upon the subject and be of interest wherever such work is contemplated4--,contract ,journal4 99 99 99 99 99 ,,mont ,,st4 ,,michel4 ,every one who has the slightest regard for historical monuments1 who values medival architecture1 or cares in the least degree for the beautiful and the picturesque1 must heartily sympathize with ,m4 ,victor ,hugo in his protest against the proposed scheme for uniting the wonderful island of ,mont ,st4 ,michel with the mainland by means of a causeway1 and possibly a railway6 ,those who know ,mont ,st4 ,michel well1 and1 like the writer1 have spent several days upon the island1 cannot but feel that such a scheme would not only be a frightful disfigurement1 but would entirely destroy all the associations and the poetry of the place4 ,practical people will say1 ,modern improvement cannot stop in its march forward to consider poetical associations and mere artistic whims and fancies4 ,now1 this would be a possible argument if ,mont ,st4 ,michel were a busy1 thriving town1 a commercial port1 or the seat of great industries2 but in a case where the only trade is that of touting1 the only visitors sightseers1 the only stock-in-trade medival remains1 surely1 from a practical point of view1 anything which will injure these antiquities will really destroy the importance of the island1 as its only value consists in its wonderful historic and artistic associations4 ,illustration3 ,,mont ,,st4 ,,michel1 ,,normandy4 ,the first glimpse of ,mont ,st4 ,michel is strange and weird in the extreme4 ,a vast ghostlike object of a very pale pinkish hue suddenly rises out of the bay1 and one's first impression is that one has been reading the ,arabian ,nights1 and that here is one of those fairy palaces which will fly off1 or gradually fade away1 or sink bodily through the water4 ,its solemn isolation1 its unearthly color1 and its flamelike outline fill the mind with astonishment4 ,mont ,st4 ,michel is by far the most perfect example of a medival fortified abbey in existence1 with its surrounding town and dependencies1 all quite perfect2 just1 in fact1 as if time had stood still with them since the fifteenth century4 ,the great granite rock rises to the height of two hundred and thirty feet out of the bay2 it is twice an island and twice a peninsula in the course of twenty-four hours4 ,the only approach is at low water1 by driving or walking across the sands4 ,when1 however1 one arrives within a few yards of the solitary gate to the town1 walking or driving has to be abandoned1 and here the commercial industries of the inhabitants commence4 ,a number of individuals1 half sailors and half fishermen1 are standing ready to carry you on their shoulders over the small gully1 which is very rarely quite dry4 ,entering through the old gate one sees two ancient pieces of cannon taken from the ,english1 who unsuccessfully laid siege to the place in #adbb4 ,close to the gate are the two rival inns1 which are very primitive in their arrangement1 the entrance hall forming the kitchen1 as in many old ,breton houses4 ,a second frowning old gateway leads to the single street1 which1 passing between two rows of antique gabled houses1 and under the chancel of the little parish church1 conducts one to the almost interminable flight of stone steps leading to the gateway of the monastery4 ,upon ringing the bell a polite lay brother opens the iron-studded door1 and we are admitted into a solemn1 vaulted hall1 with another stone staircase opposite4 ,here we go up and up1 to a second vaulted hall1 where1 in olden times1 we should have had to give up any arms which we were carrying4 ,then another stone staircase1 which lands us in a small court with a well in it1 at the opposite end of which is a heavy and solid arched doorway4 ,we pass through this1 expecting to find ourselves on the top of the central tower of the church at least1 and are surprised to find ourselves in the solemn and almost dark crypt of the church4 ,here we have climbed up some #bcj feet above the world and the sea to find ourselves in an underground vault2 up in the air and down under the rock at the same time4 ,wonderfully beautiful is this strange crypt1 when one's eye gets accustomed to the gloom1 with its exquisite ribbed and vaulted roof1 supported upon huge circular columns4 ,returning to the court1 another doorway conducts us into a most superb ,gothic hall1 with a row of slender columns down the center4 ,this was the monks' refectory in ancient times2 adjoining this is another grand hall1 divided into four aisles by rows of granite columns1 all of the most perfect thirteenth century work4 ,above these are two other halls1 still more magnificent than those below4 ,one of these1 called the ,salle des ,chevaliers1 is probably the most beautiful ,gothic hall in existence4 ,again a flight of stone stairs1 and we find ourselves1 where we should certainly not have expected1 in the cloisters of the monastery1 the exquisite architecture of which1 with its countless marble columns and delicate double arcades1 cannot be described4 ,the church deserves a few words1 as it is a veritable cathedral as to size and grandeur4 ,the choir is immensely lofty1 and constructed of granite most elaborately wrought in the later ,gothic or flamboyant style4 ,the nave and transepts are in the old ,romanesque style1 with solid pillars and low round arches4 ,the church is beautifully kept1 and contains some very interesting old reredoses and altars with carving in alabaster4 ,the one modern altar in the ,lady ,chapel is composed entirely of silver6 ,our space will not permit us to describe the numerous interesting old ,abbey buildings--the library1 the prior's lodging1 the vast kitchen1 the prisons1 the dungeons1 and the means of supplying the place in times of siege4 ,the proposed causeway would join the island to the left of our view1 and our readers can imagine the abominable effect of a high embankment disfiguring this point1 and breaking through the interesting old walls and towers1 with1 perhaps1 a ,brummagem ,gothic station against the old time-worn gateway4--,h4 ,w4 ,brewer1 in ,london ,graphic4 99 99 99 99 99 ,,adornments ,,of ,,the ,,new ,,post ,,office ,,at ,,leipzig4 ,the cuts given herewith1 taken from the ,illustrirte ,zeitung1 represent two statues for the new ,post ,office at ,leipzig4 ,the sculptor1 ,kaffsack1 has represented the post and the telegraph as winged female figures4 ,the figure representing ,mail holds a horn or trumpet in her left hand1 and a letter in her right hand4 ,the figure representing ,telegraphy holds a bunch of thunderbolts in her left hand1 and unrolls a band for receiving dispatches with her right hand4 ,it will be observed that the figure representing ,telegraphy is made much lighter and more graceful than the figure representing ,mail1 and has also a more energetic expression of countenance1 thus indicating the greater speed of ,telegraphy4 ,illustration3 ,,adornments ,,of ,,the ,,new ,,post ,,office1 ,,leipzig1 ,,germany4 99 99 99 99 99 ,,coal ,,gas ,,as ,a ,,labor-,,saving ,,agent ,,in ,,mechanical ,,trades4 ,by ,,thomas ,,fletcher1 ,f4,c4,s4 ,gas1 as a fuel1 is an absolute necessity to the economical carrying out of many commercial processes4 ,it is often used in the crudest and most costly way2 a burner may be perfect for one purpose1 yet exceedingly wasteful for another1 and however good it may be1 an error of judgment in its application may lead to its total condemnation4 ,an excess of chimney draught1 in cases where a flue is necessary1 may pull in sufficient excess of cold air to almost neutralize the whole power of the burner1 unless a damper is used with judgment4 ,with solid fuel1 an excess of draught causes more fuel to be burnt1 but with gas the fuel is adjusted and limited2 there is no margin or store of fuel ready to combine with the excess of air1 which1 therefore1 lowers the amount of work done by its cooling power4 ,the power of any burner1 for any specified purpose1 depends not only on its perfection1 but to a far greater extent on the difference in the temperature of the flame and of the object to be heated4 ,for instance1 if a bright red heat is required1 it is not possible to obtain this temperature economically with any burner working without an artificial blast of air2 the difference between the temperature of the flame and that of the object heated is too little to enable the heat to be taken up freely or quickly1 and the result is a large loss of costly fuel4 ,if we want to obtain high temperatures economically1 an artificial blast of air is necessary1 and the heavier the pressure of air1 the greater the economy4 ,on the contrary1 low temperatures and diffused heat are obtained best by flames without any artificial air supply4 ,for such purposes as ovens1 disinfecting chambers1 japanners' stoves1 founders' core drying1 and similar requirements the best results are obtained by a number of separate jets of flame at the lowest part of the inclosed space1 and the use of either illuminating or blue flames is a matter of no importance1 as the total amount of heated air from either character of flame is the same4 ,if there is any preference1 it may be given to illuminating flames1 as the proportion of radiant heat is greater1 and this makes the average temperature of the inclosed space more equal2 but on the other hand1 may be considered the greater liability of the very fine holes1 necessary for illuminating flames1 to be choked with dust and dirt4 ,this may1 to a great exent1 be obviated by using very small union jets1 and setting them horizontally1 so as to make a flat horizontal sheet of flame4 ,burners placed this way are practically safe from the interference of falling dust or dirt1 but not from splashes4 ,falling dirt or splashes must always be considered in the arrangement of any burners1 and the ventilation must be no greater than is absolutely necessary for the required work4 ,in cooking1 this limit of ventilation may be exceeded1 as most things are better cooked with a free ventilation1 the extra cost of fuel being well compensated for by the better quality of the result4 ,the air in an oven or inclosed space heated by flames inside is similar in character to highly superheated steam4 ,it contains a large proportion of moisture1 and yet has the power of drying any substance which is heated to near its own temperature4 ,a mass of cold metal placed in the oven is instantly bedewed with moisture1 which dries up as the temperature of the metal rises4 ,this is1 for many purposes1 an objection1 and the remedy is to close the bottom of the oven and place burners underneath4 ,if for drying purposes and a current of air is necessary1 the simplest way is to place in the bottom of oven the a number of tubes hanging downward in such a position that the heat of the flame acts both on the bottom of the oven and the sides of the tubes1 which1 of course1 must be long enough for the lower opening to be well below the level of the flame4 ,the exit may be at any level1 but for drying purposes it is better at the top1 and it should be controlled by a damper to prevent cooling by excessive currents of air4 ,if not otherwise objectionable1 the arrangement of flames inside the oven is far the most economical in use4 ,where an oven or drying chamber is used continuously1 it should be jacketed with slag wool or boiler composition1 but for many purposes this is no advantage4 ,as an example both ways1 ,i will instance the drying of founders' cores where there is only one blow per day4 ,the cores of an ordinary foundry can be dried by gas in a common sheet iron even in about half an hour2 any accumulation of heat after that time would be useless1 and a jacketed oven would be of no advantage4 ,for the disinfection of clothes in vagrant wards and hospitals for infectious diseases1 on the contrary1 a continued heat is necessary1 and in this case the accumulation of reserve heat1 which takes place slowly in a jacketed oven1 becomes of value1 as the gas can be turned low or out1 and the ventilators closed1 insuring a more complete disinfection with a much smaller gas consumption4 ,where an oven or heated chamber is much used for periods of over half an hour at once1 a non-conducting casing pays well by reduced gas consumption4 ,for albumen and glue drying1 leather enameling1 tobacco drying1 and purposes where a large space has to be very slightly and equally warmed when the weather is unfavorable1 steam-pipes are generally used1 but1 not being always available1 an exceedingly good arrangement may be made by placing at intervals in the room gas burners1 of any construction1 close to the floor1 and surrounded with a sheet-iron cylinder1 say #b ft4 or #c ft4 high4 ,the top of these cylinders must be connected throughout with a fairly large flue1 which will take the products of combustion from the whole1 and this flue must be carried either horizontally1 or with a slight rise1 so as to utilize all the waste heat4 ,the reason for having a number of stoves at intervals is that the heat in a flue will not carry1 for any useful purpose1 more than about #h ft4 or #aj ft41 and a single stove would give an irregular temperature in any except a very small room4 ,if all are not used at once1 the flues of those not in use may be closed by a damper to prevent down draught4 ,the use of hot water pipes heated by gas may also be occasionally advisable1 but1 unless for some special reason1 it is much more economical to use coal or coke1 as the bulk of water makes an exceedingly good regulator1 and makes a fire practically as steady and reliable as gas1 thus superseding the more costly fuel4 ,for one of my own purposes ,i need hot-water pipes1 having very little variation in temperature night and day2 and using coke for economy's sake1 ,i get a regular temperature by heating a large quantity of water1 about #bjj gallons1 with the fire1 and inclosing this in a tank jacketed with slag wool4 ,my circulating pipes run from this tank1 and a practically steady temperature1 night and day1 can be obtained with the most irregular firing1 and occasional extinction of the fire for several hours at once4 ,for the heating of liquids1 the greatest economy is to be obtained from one single flame1 of as high a temperature as can conveniently be obtained1 and the flame must be in actual contact with the vessel to be heated4 ,in jacketing vessels1 to prevent draughts1 care must be taken that the jackets do not cause currents of cold air to rise rapidly up the sides of the vessel1 and so cool it4 ,if this is the case1 the use of a jacket1 instead of being an economy1 is a positive expense1 and waste of heat4 ,many processes1 such as making oil and turpentine varnishes1 require a heat under instant control1 and in these the use of gas is an important matter1 as the loss and risk of fire are very serious elements of expense1 more especially in small works where special and costly preparations for contingencies cannot be afforded4 ,i have here a burner which1 for its power1 is1 perhaps1 the most compact and gives the highest temperature of any burner yet known1 and it is easily made in almost any size2 it has1 ,i think1 many special advantages4 ,the use of gauze1 which is its only weak point1 is more than compensated for by the very high duties obtained in practice with it1 owing to the compactness and concentration of the heat obtained4 ,the following extract from my communication to the ,gas ,institute will give all particulars as to the constructive detail of this burner4 ,those who wish to go further into the matter will find the paper referred to in the publication of the ,gas ,institute for the current year1 and also in the ,journal of ,gas ,lighting1 ,june #bf1 #ahhc1 and the ,review of ,gas and ,water ,engineering1 ,june #af1 #ahhc4 ,the first and most important part is the mixing chamber or tube1 one end of which is supplied separately with gas and air1 which at the other end are1 or should be1 delivered as a perfect mixture4 ,it may be taken as a rule that this tube1 if horizontal1 should not be less in length than four and a half times or more than six times its diameter4 ,it is a common practice to diminish or make conical-shaped tubes4 ,all my experience goes to prove that1 excepting a very trifling allowance for friction1 the area of the smallest part of the tube rules the power1 the value of the mixing-tube being no more than that of the smallest part4 ,if the mixing-tube is upright1 new sources of interference comes in2 notably the varying specific gravity of the mixture4 ,except with one definite gas supply1 the result is always more or less imperfect1 and regular proportions cannot be obtained4 ,this is now so well known that the upright form has been practically discarded for many years1 and is now only used where the peculiar necessities of the case give some special advantage4 ,illustration3 ,fig4 #a4 ,,special ,,high ,,power ,,burner4 ,,shewing ,,attachment ,b ,,when ,,used ,,with ,a ,,blast ,,of ,,air ,the diameter of the mixing tube is a matter of importance1 as it rules the quantity of gas which can be satisfactorily burnt in any arrangement4 ,with large flames1 given a certain size of gas-jet1 the diameter of the mixing-tube should be not less than ten times as great4 ,for instance1 at #a inch pressure1 a jet having a bore of #a_/h inch will pass about #bj cubic feet of gas per hour4 ,to burn this quantity of gas1 a mixing tube is necessary #aj_/h or #a inch in diameter4 ,by the first rule this tube must be in length equal to four and a half times its diameter1 or #e-e_/h inches4 ,it would appear that the mixing-tube1 having #ajj times the area of the gas jet1 is out of all proportion to the size necessary for obtaining a mixture of one of gas to nine or ten of air2 but it must be remembered that the gas is supplied under pressure4 ,it is therefore evident that no mere calculation of areas can be taken1 into account1 unless the difference in pressure of the supply is also considered4 ,a complete reversal of this law is shown in that ruling the construction of blowpipes1 which ,i have already given in a previous paper on ',the ,use and ,construction of the ,blowpipe4' ,in these the air supply1 being under a heavier pressure1 is much smaller in area than the gas inlet2 and1 to obtain maximum power1 the air-jet requires to be enlarged in proportion to the gas pressure4 ,given a certain area of tube delivering a combustible mixture1 the outlet for this mixture must be neither more nor less than the size of the tube4 ,taking an ordinary drilled tube1 such as is commonly made1 and of the dimensions before given--i4 e41 #a inch bore--if the holes are drilled #a_/h inch in diameter the tube will supply #aj x #aj #ajj of these holes4 ,in practice this rule may be modified4 ,the variations from the rule1 however1 must be a matter of experience with each form of burner4 ,there is also the fact that with small divided flames it is not necessary to mix so large a proportion of air1 as each flame will take up air1 on its external surface2 but in this case the flames are longer1 hollow1 and of lower temperature4 ,as a matter of actual practice1 where a burner is used which gives a number of flames or jets1 the diameter of the mixing-tube does not need to exceed eight times the diameter of the gas jet2 the remainder of the air required being taken up by the surfaces of the flames4 ,wire gauze1 made of wire the thickness of #bb iron wire gauge1 #bj wires to the linear inch1 and tinned after weaving1 has an area in the holes of its surface4 ,by calculation1 the area of a gauze surface in a burner should1 therefore1 be taken at four times that of the tube1 and our standard of #a inch tube requires a gauze surface of #b inches in diameter4 ,this rule is subject to variation in burners of a small size1 owing to the air that can1 if required1 be taken up by the external surface of the flame1 which1 of course1 is much greater in proportion in a small flame than in a large one4 ,where the diameter of the gauze is1 say1 not over one or two inches1 the theoretical maximum gas supply may be exceeded1 and a varying compensation is necessary with each size4 ,my rule is intended to apply to burners of larger diameters1 where the external air supply plays a comparatively unimportant part4 ,illustration3 ,fig4 #b4 ,it must be remembered that burners of this class1 which burn without the necessity of an external air supply in a flame which is solid1 require the mixture to be correct in proportions4 ,a very slight variation makes an imperfect flame4 ,not only does the gas jet require to be adjusted with great precision1 but it also needs more or less adjustment for different qualities of gas4 ,an ordinary hollow or divided flame is able to take up on its surface any deficiency of air supply2 but with the high power solid flames the outside surface is small1 and the consequence is that one of these burners1 adjusted for gas of poor quality1 may1 when used with rich gas1 give a long hollow or smoky flame1 unless the gas jet be reduced in size4 ,when perfect1 the flame shows a film of green on the surface of the gauze2 and if a richer gas is used1 the green film lifts away4 ,to cause this to fall again1 and to produce a solid flame1 it is necessary to take out the gas jet1 and tap the end with a hammer until1 on trial1 it is found correct4 ,if too small1 the green film lies so closely as to make the gauze red hot4 ,where the 'tailing up' of the carbonic oxide flame is objectionable1 there is no practical difficulty whatever in constructing these burners as a ring1 with an air supply in the center1 which greatly reduces the length of the 'tail4' ,in practice it is a decided advantage to have a center air-way in all burners of more than about #b in4 diameter1 as it enables the injecting tube to be slightly shortened1 and lessens the liability of the green film to lift with varying qualities of gas4 ,in this class of burner ,i have adopted the small central air-way as a decided improvement in the burners4 ,in such processes as the roasting of coffee1 chiccory1 grain1 etc41 a diffused heat is necessary1 but of much greater intensity than can be obtained with economy from heated air4 ,in these cases the application of a direct flame is necessary1 and it may be in actual contact with the substances to be heated1 provided these are kept in constant and rapid motion4 ,the use of a revolving cylinder brings in complications with any burner which is supplied with gas at ordinary pressures without any artificial air supply1 as the currents of air caused by the motion of the cylinder interfere with the satisfactory working of any burner2 and the air supply must be either protected from draughts and irregular air currents1 or the air must be applied artificially from some independent source4 ,one exceedingly good way of making any burner work1 independently of the currents caused by a revolving cylinder1 is to apply the flame inside the cylinder at the center1 making the substances to be heated to fall in a continuous stream through the flame4 ,this system is not applicable to fine powders or sticky substances1 as it necessitates the perforation of the cylinder1 to allow of the escape of products of combustion4 ,for this class of work1 a very concentrated heat is not desirable1 as a rule1 and a slit or a perforated burner is preferable4 ,of this class of burner ,i have here a sample1 which is not only new in its constructive details1 but has great and special advantages for many purposes4 ,as you see1 it resembles a number of ordinary furnace bars1 with this difference1 that each bar is a burner2 in fact1 it is an ordinary furnace grate1 which supplies its own fuel4 ,with the usual day pressure of gas#a inch of water1 this burner will1 at its maximum power1 consume about #ajj cubic feet of gas per hour per square foot of burner surface1 and as it can readily be made almost any form or size1 its adaptability for a great number of uses is evident4 ,i have made it in many sizes and shapes1 to give flames from inch wide by #e feet long to large square or oblong blocks4 ,by applying a blast of air at the ordinary gas jets1 and supplying the gas by a separate pipe1 or series of pipes1 below the open end of the burner1 this can be converted into a furnace of extraordinary power4 ,it is quite possible to burn as much as #b1jjj cubic feet of gas per hour per square foot of burner surface1 producing a heat sufficient to fuse any ordinary crucible4 ,you see its power when ,i place a bundle of iron wire in the flame2 it is1 in fact1 a concentration of hundreds or thousands of powerful blowpipe flames in one mass4 ,it has also this advantage1 that with a blast of air it will burn and work equally well any side up1 and the flames can therefore be directed straight on their work without loss4 ,it is1 in one form or another1 almost a universal burner1 as it can be readily adapted to almost any purpose1 from tempering a row of needles to making steam for a #bjj horse power steam engine4 ,it is easy to make1 easy to manage1 practically indestructible1 and for commercial purposes has1 ,i think1 a general adaptability which will bring it1 in one form or another1 into almost universal use4 ,i may say that when we are in a special fix1 this has in every case landed us out of the difficulty4 ,for heating large plates of metal equally1 for drying paper impressions for stereotypers1 hot pressing hosiery1 crumpet baking1 working up plastic masses which can only be worked hot1 and work of this class1 a number of separate flames equally diffused under the whole surface of the plate are necessary to equalize the heat1 unless the plate is very thick1 and these are better if produced by a mixture of gas and air2 but in heating wide plates one difficulty must always be remembered1 the burnt gases from the center flames can only escape by passing over the outer flames1 and therefore a space must be left between the top of the flame and the plate1 or the outer flames will be smothered and make a most offensive smell4 ,in hosiery presses1 printers' arming presses1 and many others1 the top plate also requires to be heated4 ,the best way to do this is to use a number of blowpipe flames directed downward4 ,in many cases the supply of air under pressure is a practical difficulty and objection4 ,this is overcome1 to a certain extent1 by the use of a thick upper plate with a number of horizontal holes1 into which a ,bunsen flame is directed4 ,in every case ,i have seen1 without one single exception1 the holes are either too small1 or the burner is placed too close1 and the consequence is that the gas1 instead of burning inside the holes1 as it should1 passes through partially unburnt1 and is consumed at the opposite end1 where it is absolutely useless1 the flame not being in contact with or under the surface to be heated1 and therefore doing no work4 ,in hosiery presses this is a great objection1 as the holes are so long that an equal heat is simply impossible1 and the only remedy is to use a blowpipe flame1 which forces sufficient air in with the gas to insure combustion where the heat is necessary4 ,the same remark applies to crape and embossing rollers4 ,for the production of heat in confined spaces and difficult position1 the use of an artificial blast of air is becoming an acknowledged necessity1 and the small ,roots blowers now made for such purposes1 and driven by power1 are coming rapidly into use4 ,sometimes a plate is required to be heated to a high temperature in one confined spot1 and1 as an example of this1 ,i may take the bluing of the hands of watches4 ,for this purpose ,i have made several arrangements1 and perhaps the best is a thin copper plate1 bent down at one side to a right angle4 ,in this angle1 underneath1 is directed a very fine blowpipe flame on one spot1 and the hands are passed singly over this spot until the color comes1 when they are instantly pushed over the edge4 ,i have here the arrangement which is generally used for this purpose4 ,for the bluing of clock hands1 a larger and more equally heated surface is required1 and this can be obtained by a small powerful burner without a blast of air1 using a rather thicker plate to equalize the heat4 ,the same arrangement may be used with advantage for tempering small cutters for ornamental turning1 penknife-blades1 etc41 and in these cases the cooler part of the plate is of great value1 as it enables the thicker parts to be slowly and equally heated up2 the application of a mechanical arrangement to pass the articles to be heated in a regular succession is a matter easily managed4 ,illustration3 ,,fig4 #c4 ,,blueing ,,watch ,,hands ,,tempering ,,small ,,tools ,among other things which have several times come under my notice may be mentioned cremation furnaces1 but ,i have not yet met1 with1 or been able to devise1 any burner for ordinary coal gas which has worked satisfactorily4 ,this fuel is apparently unfitted for the work1 and the best arrangement ,i know is a number of pipes delivering ordinary producer gas from the ,wilson or ,dowson generators1 in exactly the same way as is at present used for firing horizontal steam boilers4 ,for heating book finishers' tools1 a ring-flame is the simplest1 the tools being supported a little distance above the flame2 the usual plan of heating a plate1 and placing the ends of the tools on this1 necessitates at least double the gas consumption as compared with an open flame4 ,for type-founding machines1 bullet moulding1 stereotype metal melting1 solder making1 lead melting1 etc41 one burner1 or rather one flame1 should be used of a suitable power for the work1 and this should be as perfect and of as high a temperature as possible to insure economy4 ,it is now a simple matter1 owing to recent researches in the theory of heating burners1 to obtain flames of any power without practical limit1 which1 without any artificial air supply1 will do all which is necessary in this class of work1 and the required arrangements are exceedingly simple4 ,with these trades may be classed1 also1 the concentration and distillation of acids and liquids boiling at a high temperature1 and we may also include baths for tinning small articles1 and the tinning by fusion of sheet copper1 the same burners being applicable1 and perfectly suited to all these requirements1 unless the tinning baths are long and narrow1 in which case the furnace-bar burners again come to the front as the best2 as1 if we are to use gas economically1 the flame must be the same shape as the vessel to be treated4 ,we may now consider the heating of blanks for stamping1 hardening the points of spindles1 finishing the ends of umbrella tips1 and work where a small article1 or a small part of any article1 has to be heated to a high temperature with speed and certainty4 ,for these a long and narrow flame is necessary1 and ,i may mention that in cases where a high speed of delivery is required1 and a small part only has to be heated1 such as1 for instance1 in the hardening of the points of spindles for cotton machinery1 ,i have made burners giving a flame of exceedingly high temperature only inch wide and five feet long4 ,this flame is produced by the assistance of a blast of air1 and is of sufficiently high temperature to fuse the spindle in a few minutes4 ,the points only project over the flame1 and the spindles are carried mechanically at such a speed that at the end of the five feet traverse they are red hot1 and drop into water4 ,more than one hundred are in the flame at once1 lying side by side4 ,for heating blanks for stamping1 the furnace bar-burner is perfectly suited1 and in this work the chute supplying the blanks to the machine should be made of two fireclay sides1 with an opening for the flame between the chute and flame being placed at a sharp angle1 to prevent risk of the blanks sticking or overriding each other4 ,a blowpipe may also be used with good effect1 as shown in the above engraving1 and in many cases it is preferable and much easier to manage4 ,in some cases the direct contact of the flame would spoil the articles to be heated1 and instead of the arrangement mentioned1 a tube of iron1 fireclay1 or other suitable material is heated1 and the articles are passed through it4 ,this system of continuous feed1 through a tube1 has been applied to the firing of small articles of pottery1 and might possibly be well adapted1 among other things1 to the production of gas-burners4 ,illustration3 ,,fig4 #d4 ,where the contact of air with the heated articles is injurious1 many plans have been tried to keep the ends closed as much as possible1 but ,i believe no more perfect and simple seal against the admission of air can be devised than to turn a jet of pure gas1 unmixed with air1 into each end of the tube4 ,this is an absolute seal against the entry of oxygen in an uncombined state2 free oxygen cannot exist at a very high temperature in the presence of coal gas4 ,for many trades there is a demand for hardened and tempered steel wire1 either round or flattened1 and the production of this has led to many attempts to obtain a satisfactory continuous process4 ,the common method now1 which is worked as a secret process by most firms1 is to pass the wire through a tube to heat it1 as already described1 and to run it direct from the tube through a hole in the side of a box filled with oil1 the whole being packed with asbestos1 to prevent leakage2 from this it is passed through another similar hole on the opposite side1 either over a plate heated to the right temperature1 or over a narrow open flame of sufficient length and power to give the correct heat for tempering4 ,where absolute precision is necessary1 the gas supply must be adapted by an automatic regulator on the main1 to prevent the slightest variation of heat4 ,once adjusted1 the production of flat and round spring wire by the mile is an exceedingly simple matter4 ,it is quite possible to obtain absolute precision in temperature by a proper adjustment of the gas pressure1 and as this is1 for tempering steel articles and some other purposes1 a matter of great importance1 it is worth some consideration4 ,no pressure regulator alone will give an absolutely steady supply2 but if we put on first a regulator1 adjusted to the minimum pressure of supply1 say one inch of water1 and then fix another on the same pipe1 adjusted to a slightly lower pressure1 say #i_/aj of an inch1 the first regulator does the rough adjustment1 and the second one will then give an absolutely steady supply1 provided always that the regulators are both capable of passing more gas than is likely to be ever required4 ,no regulator can be relied on for absolute precision1 if worked up to its maximum possible capacity4 ,illustration3 ,fig4 #e4 ,,arrangement ,,for ,,heating ,,blanks ,,for ,,stamping ,,or ,,hardening4 ,among other applications of a long narrow flame of high power1 may be mentioned the brazing of long lengths of tube1 in fact the application of flames of this form1 with and without a blast of air1 for different temperatures1 are almost endless4 ,the thousands of uses to which blowpipes are adapted are so well known1 that they need no mention1 except the curiously ignored fact that the power of any blowpipe depends on the air pressure4 ,a compact flame of high temperature cannot be obtained except with a heavy air pressure1 and the ignorance of this fact has caused an immense number of unexplained failures4 ,many people think that one blower is as good as another1 and expect that a fan giving a pressure equal to1 say1 the height of a two inch column of water should do the same work as a blower giving a pressure ten to twenty times as great4 ,the construction and power of blowpipes1 with the laws ruling the proportions and power1 will be found in an article on ,blowpipe ,construction1 published in ,design and ,work1 ,march1 #ahha1 and as the matter is there fully treated1 no further reference to the subject is necessary4 ,in the more recent forms of gas-engine1 the charge is exploded by a wrought iron tube1 heated to redness by the external application of a gas flame4 ,this1 although considered satisfactory by the makers1 appears to me to be an exceedingly crude way of getting over the difficulty2 and ,i offer it as a suggestion1 that a very small platinum tube shall be used instead of iron4 ,this1 if made with a porous or spongy internal coating1 would fire the charge with certainty1 at a lower temperature than iron1 and it could be made so thin and small in diameter1 without risk of deterioration or loss of strength1 that an exceedingly small flame could be used to heat it up4 ,as it would be fully heated in a very few seconds1 the delay in starting would be obviated4 ,illustration3 ,fig4 #f4 ,there are many purposes for which a red heat is needed for slow continuous processes on a small scale1 such as case-hardening small steel goods1 annealing1 heating light steel articles for hardening1 and a great variety of other similar processes4 ,this1 until recently1 has required the use either of a rather complicated furnace1 or a blast of air under pressure1 to increase the rapidity of combustion4 ,since the conclusion of my experiments on the theoretical construction of burners1 ,i have found that the high-power burners1 previously described1 are capable of heating a crucible equal in size to their own diameter to bright redness without the assistance of a chimney1 provided the crucible is protected from draughts by a fireclay cylinder4 ,this is an important point1 as it renders the production of a continuous bright red heat a matter of the greatest ease1 even in crucibles of a comparatively large size4 ,where the heat is steady1 and certain not to rise above a definite point1 it can safely be used for such purposes as hardening penknife blades and other articles which are very irregular in thickness1 the thin edges not being liable to be burnt or damaged by overheating4 ,for the highest temperatures air under pressure is a necessity1 as we require a large quantity of gas burnt in as small a space as possible with the maximum speed1 and given this air supply1 we are very little hampered by conditions1 as an explosive mixture may be blown through a gauze into a fireclay chamber1 closed1 except so far as is necessary to allow the escape or burnt gases4 ,the speed of combustion is limited only by the speed of supply of air and gas1 and by increasing these there is no practical limit to the heat which can be obtained4 ,when we have to do with the reduction of samples of refractory ores1 testing the comparative fusibility of different samples of firebricks1 or alloys1 etc41 the use of an explosive mixture blown into and burning in a close chamber is invaluable1 and the ease and certainty with which any temperature may be obtained has led to great discoveries1 and the revolutionizing of many commercial processes4 ,recent experiments have proved that1 by a modification in the form of the well-known injector furnace1 an enormous increase of temperature may be obtained4 ,i have1 in actual work1 obtained the fusing point of cast iron in two minutes1 starting all cold1 and have fused every furnace casing ,i have yet been able to produce4 ,if infusible casings can be made1 ,i think ,i am not overstating facts in saying that any temperature required can and will eventually be obtained with the greatest ease4 ,what the limit is ,i have as yet not been able to discover4 ,there is one more application of gas1 as a fuel1 which1 discovered and published by myself some two years ago1 has yet to become generally known1 and in some special processes may prove exceedingly valuable4 ,this is the addition of a very small quantity or coal gas1 or light petroleum vapors1 to the air supplied by a blower or chimney pull1 to furnaces burning coke or charcoal4 ,the instant and great rise in temperature of the furnace1 and the greater stability of the solid fuel used1 are extraordinary4 ,this is1 in fact1 a practical application of the well-known flameless combustion1 the only signs that the gas is being burnt being a great rise in temperature and a decreased consumption of the solid fuel2 in fact1 if the gas is in correct proportion1 the solid fuel remains unburnt1 or nearly so1 in spite of the high temperature4 ,in cases where a sudden rise in temperature is required in a furnace1 or where the power is deficient1 this method of supplementing and increasing the heat will be found of very great service1 and processes liable to be checked by making up a fire with fresh fuel can be carried on without check1 even after the solid fuel has almost entirely disappeared4 ,that a solid fuel is quite unnecessary1 ,i will prove in a very simple manner1 by burning a mixture of coal gas and air without a flame1 in a bundle of iron wire4 ,the heat is sufficient to fuse the wrought iron with ease1 and the glare inside the bundle of wire is painful to the eyes4 ,the same result could be obtained by a pile of red-hot lumps of firebrick1 and the same heat obtained also without a trace of flame4 ,it is not possible to enter fully into such a wide and important subject in a single lecture1 and the suggestions now given are simply hints for the guidance for those who need or desire to experiment4 ,no doubt we shall have1 after a time1 some text-books and other literature on this subject1 which is one of great importance to many industries2 and it is necessary for experimental work and applications to new industries1 that the experimenter shall not only be able to purchase special burners1 but that he shall have fundamental laws laid down which will enable him to construct them for himself1 so as to have his experiments under his own control4 ,the difficulty in the way of literature on the subject is that those few who have worked in the matter are busy men1 with little time which is not already fully employed4 ,pioneers on new ground have a great liability to generalize and jump at conclusions1 and the necessary exact work and detail must1 to a great extent1 be left to those who follow on tracks already roughly marked out4 ,of the special trades which have come under my observation1 ,i have only had time to mention a very few4 ,it appears to me that there are very few manufacturing processes of any kind which could not be simplified by the use of gas as a fuel1 from the production of electric light apparatus to the manufacture of explosives1 cotton stockings1 beer1 catgut1 glue1 umbrellas1 ink1 fish-hook1 medals1 stained glass windows1 brushes1 and other trades equally various1 which come daily under my own notice4 99 99 99 99 99 ,a man was received into the ,laborisire ,hospital1 ,paris1 the other day1 with a yard of rope hanging from his mouth4 ,traction upon the cord revealed a section of clothes line measuring eight feet4 ,he had been surprised in an attempt at suicide and had tried to conceal his design by swallowing the cord4 ,he lived1 of course--they generally do4 99 99 99 99 99 ,,instantaneous ,,photography4 ,a certain number of the readers of this journal are occupied with photography1 and all assuredly are interested in this marvelous art1 whose progress is so remarkable4 ,so it has seemed to us that it would be of interest to treat of a question that is the order of the day4 ,we desire to speak of those photographic apparatus called instantaneous shutters4 ,numerous apparatus of this kind have been proposed to the public1 and several even have been described in this journal1 but we have to state that1 despite the success in certain cases1 none of them has proved remarkable for its qualities and superiority4 ,this is due1 we believe1 to the fact that inventors1 while showing arrangements that were often ingenious1 have not always taken into account the end that the shutter is to subserve1 and the qualities that it must possess in order to attain such end4 ,in face of the progress made by extra rapid dry processes1 the question of shutters has become the most important1 since cabinet-making1 optics1 and photographic chemistry give us apparatus1 objectives1 and products which1 although they will doubtless be improved upon1 satisfy for the present all our needs4 ,what is understood by instantaneousness8 ,to our knowledge1 no definition thereof has as yet been given4 ,for our part1 we propose to style instantaneous any photograph that is taken in a fraction of a second that our senses will not permit us to estimate4 ,the shutter is the apparatus which allows the light to enter the photographic chamber during this very short time4 ,in order to examine the different rules that govern the question of shutters1 we shall take as an example the type styled the ,guillotine4 ,this apparatus1 as every one knows1 is a stiff plate containing an aperture and passing over the line of the rays of light4 ,some place it in front and others behind1 while others again place it within the objective4 ,let us examine and discuss what occurs in the three cases4 ,suppose a rectilinear objective of the kind most usually employed in instantaneous photography1 and an object1 ,a ,b1 that we wish to reproduce 7,fig4 #a71 the objective being provided with any sort of diaphragm4 ,the point1 ,a1 sends a bundle of rays1 ab1 to the first lens4 ,here they are slightly refracted1 and then go on parallel lines to the second lens1 where they are again refracted and form at ,a' an image of ,a4 ,it is this image that we see upon the ground glass1 and which makes an impression upon the sensitive film4 ,the point1 ,b1 behaves in the same way and gives an image at ,b'1 but1 as will be at once seen1 the image will be reversed4 ,in our figure1 ,a corresponds to the sky and ,b to the earth4 ,if1 then1 the shutter passes in front of the objective1 it will first allow of the passage of the rays which come from the sky1 then1 on continuing its travel1 it will unveil the landscape1 and lastly the ground4 ,as it is submitted to the law of the fall of bodies and has a uniformly increasing velocity1 it follows that the time of exposure will uniformly decrease between ,a' and ,b'1 and that the sky will pose longer than the foreground4 ,such a result is contrary to all photographic rules1 which require that objects shall pose so much the longer the less they are lighted4 ,this position of the guillotine shutter is absolutely false1 and must be altogether discarded4 ,if the shutter be placed behind the objective1 it will follow1 as a consequence of the same demonstration1 that the time of exposure will go diminishing from ,b' to ,a'1 and that the foreground will be exposed longer than the sky4 ,the solution is logical1 then1 and will permit of obtaining excellent negatives4 ,illustration3 ,,fig4 #a ,let us now examine how the image1 ,a',b'1 is formed4 ,the point1 ,a1 appears first1 and becomes lighter and lighter up to the moment at which all the rays that emanate from the point1 ,a1 are unveiled4 ,the point1 ,b'1 is not yet visible4 ,as the shutter continues its travel the point1 ,b'1 appears in its turn and becomes illuminated like the point1 ,a'4 ,at this moment the objective is completely uncovered2 the image1 ,a',b'1 is perfect1 and possesses its maximum intensity4 ,then the point1 ,a'1 gradually becomes obscured and disappears2 and the same is the case with all parts of ,a',b'4 ,the image is developed progressively from ,a' to ,b'1 and makes its impression upon the sensitive plate successively--a fact which1 as may be conceived1 may have its importance4 ,if1 for example1 we are photographing a ship that is being tossed about by the sea 7and we borrow this example from our colleague1 ,mr4 ,davanne71 the image of the top of the mast will not be formed at the same instant as that of the base1 and if the motion of the mast has sufficient extent it may take on a curved form1 due to the fact that it has effected a movement between the moments during which its apex and base were being photographed4 ,upon placing the guillotine shutter in the optical center of the objective1 what will occur8 ,the shutter will permit the passage of an equal fraction of the rays derived from ,a and ,b1 that is to say1 the image will be complete from the first instant of the exposure4 ,the points1 ,a' and ,b'1 will be illuminated precisely at the same moment4 ,as the shutter continues its travel1 a fresh quantity of rays coming from ,a and ,b will be admitted1 and the image will be illuminated more and more up to the moment at which all the rays can pass4 ,it will then possess its maximum intensity4 ,then a portion of the rays from ,a and ,b being intercepted1 the image will become darker and darker until complete extinction4 ,the image here1 then1 is not produced successively as in the former case1 but is entire from the beginning4 ,in this case the image of our mast cannot be misshapen1 since it has been accurately photographed at the same moment4 ,the true place for the guillotine shutter1 then1 from a theoretical standpoint1 is in the interior of the objective4 ,are there any other advantages to be gained by so placing it8 ,yes2 it is easy to understand that for the same time of exposure1 and consequently for the same result1 the aperture may be so much the smaller in proportion as the optical center is approached4 ,the luminous rays1 in fact1 form in the objective a double truncated cone whose upper base is equal to the diaphragm1 and the lower one to the diameter of the lenses4 ,if the aperture be equal to any diameter whatever of one of the cones1 the result will be the same2 but1 for the same period of exposure1 it will evidently prove advantageous to approach the diaphragm4 ,the ratio of the apertures that give the same results at the optical center or behind the objective is as that of the diaphragm employed to that of the back lens4 ,if the diaphragm is one centimeter and the lenses four centimeters1 an aperture of one centimeter in one case and of four in the other will give the same result4 ,we shall see further along that it is advantageous to employ apertures equal to several times the diameter of the diaphragm or lens4 ,now1 from what we have just said1 an aperture1 equal for example to four times the diaphragm1 will be only #d centimeters1 while the corresponding aperture behind the lens must be #af4 ,the dimensions of the first will be practical1 and those of the second will give too cumbersome and too fragile an apparatus4 ,but why must the aperture be larger than the diaphragm employed8 ,this is what we are going to demonstrate4 ,let us make the aperture equal to the diameter of the objective1 and see what occurs at the different periods of the exposure4 ,for the sake of clearness1 we shall suppose the velocity uniform4 ,it is evident1 a priori1 that a perfect apparatus will be the one that will allow the light to act during the entire exposure with a maximum of intensity4 ,is it thus1 when the aperture is equal to the diameter of the objective8 ,evidently not4 ,let us consult ,fig4 #b4 ,we here see the shutter progressively uncovering the objective4 ,the light will increase from ,a to ,c up to the moment when the objective is entirely uncovered1 and will then immediately decrease up to ,b4 ,the objective has operated with a maximum of light for only a short time4 ,we are far from the ideal result in which the maximum of light1 ,,cd1 should exist during the entire exposure1 and form the upper plane precisely equal to ,,ab4 ,illustration3 ,fig4 #b4 ,if we cannot obtain such a result in practice1 we must nevertheless aproximate to it4 ,we shall do so by increasing the shutter4 ,up to ,c' the apparatus will operate as before1 but from ,c' to ,d' the aperture will be complete1 and from ,d' to ,b' will decrease as has been said4 ,let us give ,a',b' the same value as ,,ab1 that is to say1 let us increase the velocity in the second case in order that the time of exposure shall be the same2 we shall at once see that in the first case the object will be completely uncovered for only a very short time1 while in the second the exposure will be perfect for a very appreciable period4 ,the time of exposure which is absolutely active1 we propose to call effective time of exposure in contradistinction to the total time of the same4 ,the more we increase the value of ,c',d'1 that is to say1 that of the effective time1 the more the ratio1 ,c',d'_/,a',b'1 will approximate to unity1 and the nearer we shall reach perfection4 ,the correlative of such elongation of the aperture is an increase in velocity which will always bring the total exposure to the same figure1 whatever be the aperture employed4 ,if the aperture be equal to two diameters1 the effective time will be equal to half the time of the total exposure2 and if it is equal to three diameters1 the exposure will be good during #b_/c of the total time4 ,this amounts to saying that the effective time of exposure is equal to n times the diameter--#a1 the velocity being supposed always uniform4 ,if we place the shutter within the objective1 it is the diameter of the diaphragm that it will be necessary to say4 ,the effective time will be equal then to n diaphragm--#a4 ,from what precedes it results that in no case should the aperture be inferior to the diaphragm1 since the former would otherwise absolutely suppress the effective time in giving a lower plane corresponding to an insufficient quantity of light4 ,moreover1 an aperature of this kind would prove injurious to the quality of the image by successively uncovering rays which do not form their image identically at the same point4 ,we are now1 then1 in presence of results that are absolutely positive1 and they are as follows3 #a4 ,the guillotine shutter should be placed in the interior of the objective and as near as possible to optical center1 that is to say1 behind the diaphragm1 since the latter is precisely in the optical center4 #b4 ,the aperture should be as wide as possible4 #c4 ,the velocity should be as great as possible4 ,in practice1 an aperture from #d to #e times the diameter of diaphragm employed will be more than sufficient1 since we shall have1 according to circumstances1 or #d_/e of the effective time4 ,moreover1 whatever be the time of exposure1 this ratio once established will be invariable1 and the apparatus will always operate identically4 ,a shutter combining these qualities will not yet be perfect4 ,it is necessary1 according to the time and the light1 that the time of exposure shall be capable of being varied4 ,in a word1 it is necessary that the apparatus shall be graduated and permit of taking views more or less quickly4 ,the different velocities might be given to the shutter by means of weights1 rubber1 or springs4 ,the latter seem to be preferable1 since they permit in the first place of operating out of the vertical2 moreover1 they are less fragile1 and1 through different tensions1 they permit of these graduations that we consider as indispensable4 ,for the current needs of practice #a_/ajj of a second is a limit that seems to us sufficient as a maximum of rapidity4 ,in order to know the time of exposure obtained we employ the following method1 which permits of graduating an apparatus rapidly and with extreme precision3 ,a band of smoked paper is fixed upon the shutter1 then a tuning-fork provided with a small stylet resting against the paper is made to vibrate4 ,better yet1 a chronograph which vibrates synchronously with a tuning-fork1 whose motion is kept up by electricity1 is put in the same place4 ,fig4 #c shows the arrangement to be employed4 ,we then let the shutter fall1 when the little stylet will inscribe a certain number of vibrations4 ,knowing the number of vibrations of the tuning-fork1 and counting the number of those inscribed upon the paper1 it is very simple to deduce therefrom the amount of the time of exposure4 ,the results of one of these experiments we have reproduced in ,fig4 #d4 ,the tuning-fork gave #ajj double vibrations per second4 ,six vibrations are included between the opening and closing of the apparatus4 ,each vibration estimated at #a_/ajj of a second4 ,the exposure was #f_/ajj of a second in round numbers4 ,this is the amount of the total time of exposure4 ,as for that of the effective time1 that is just as easily ascertained4 ,it suffices to know the number of vibrations comprised between the moment at which one point of the objective has been completely uncovered and that at which it has begun to be covered again4 ,the time is equal to #b_/ajj in round numbers4 ,in the experiment in question1 with an aperture equal to twice the diameter of the diaphragm1 we have1 then1 #a_/c of the half-open exposure2 and the amount of the effective time is #a_/c4 ,the difference that we have in practice is due to the fact that the velocity is uniformly accelerated4 ,in order to increase the amount of the effective time1 it will be only necessary to increase the aperture of the shutter and apply again the method that we have just pointed out4 ,illustration3 ,,fig4 #c4 ,so much for the material part of the apparatus4 ,it will be necessary in addition to acquire sufficient individual experience to be able to estimate the intensity of the light1 and consequently to judge of the diaphragm to be employed and the velocity to be obtained4 ,it must not be forgotten that such or such an object having a relatively slow speed will not be sufficiently sharp on the negative if it is too near the apparatus1 while such or such another1 much more rapid1 might nevertheless be caught if sufficient distance intervened4 ,here it is that will appear the skill of the amateur1 who will find it possible to obtain the said object as large as possible and with a maximum degree of sharpness4 ,we have seen what diverse qualities should be possessed by a good guillotine shutter1 and it is evident that the same should be found in all apparatus of the kind4 ,in our opinion the guillotine is a well defined type that possesses one capital advantage1 and that is that it permits of the use of aperatures as wide as may be desired for the same time of exposure4 ,it is a question1 as we have seen1 of velocity4 ,consequently1 however short the exposure be1 it will always be possible to operate with a full amount of light during the greater part of the exposure4 ,it is necessary to dwell upon this point1 since in another kind of apparatus that possesses a closing and opening shutter the same result cannot be reached4 ,in the ,boca apparatus1 for instance1 we remark that at a given moment the time of exposure is reduced to nothing1 as the closing shutter covers the objective before the latter has been unmasked by the opening one4 ,in all exposures1 in fact1 the times of opening and closing have a constant value4 ,it follows that the shorter the exposure is1 the greater becomes such value1 and to such a point that1 at a given moment1 the apparatus no longer make an exposure4 ,illustration3 ,,fig4 #d4 ,in the guillotine1 on the contrary1 the same space always intervenes between the time of opening and closing1 since it is fixed in an unvarying manner by the diameter at the aperature4 ,then1 the greater the velocity1 the more the time of opening and closing diminishes4 ,if the ratio of the effective to the total time of exposure is #c_/d1 for example1 it will be invariable1 whatever be the velocity4 ,in concluding1 we will remark that1 without employing springs1 we may increase the aperture of the shutter without varying the time of exposure4 ,to effect this it is only necessary to raise the point of the shutter's drop4 ,in fact1 as may be seen in ,fig4 #d1 all the vibrations of the stylet corresponding to #a_/ajj of a second always continue to elongate1 and it will consequently be possible for the same time of exposure to considerably increase the aperture and1 as a consequence1 the effective time1 by causing the guillotine to drop from a greater elevation4 ,from this study1 which has principally concerned the guillotine shutter1 can we draw the deduction that this type of apparatus will become a definite one8 ,we think not4 ,in fact1 along with its decided advantages the guillotine has a few defects that cannot be passed over in silence4 ,the aperture1 in measure as it is increased1 renders the apparatus delicate and subject to become bent4 ,if1 in order to obviate this trouble1 we employ plates of steels1 we increase its weight considerably1 and the chamber becomes subject to vibration at the moment the shutter drops4 ,if rubber or springs are used for increasing the velocity1 it is still worse4 ,moreover1 it is quite difficult to obtain a graduation1 and to our knowledge1 and probably for this reason1 it has not yet been applied4 ,the reader will please excuse us for this perhaps somewhat dry theoretical expose1 but we have thought it well to give it in the hope that it might well show the qualities that should be required of a photographic shutter and particularly of the guillotine4 ,moreover1 at the point to which photography has arrived it is no longer permitted to do things by halves4 ,after the memorable discoveries of ,nicephore1 ,niepce1 ,daguerre1 and ,talbot1 photography remained for some time stationary1 limited to the production of portraits and landscapes4 ,but for a few years past it has taken a new impetus1 and new processes have come to the surface4 ,in the graphic arts and in the sciences it has taken considerable place4 ,being the daughter of chemistry and physics1 it is not astonishing that we require of it the precision of both4 ,it is1 moreover1 through a profound study of the reactions that gave it birth and through a knowledge of the laws of optics that it has come into current use in laboratories4 ,in fact1 it alone is capable of giving with an undoubted character of truthfulness a durable vestige of certain fleeting phenomena4-- ,a4 ,londe1 in ,la ,nature4 99 99 99 99 99 ,,falconetti',s ,,continuously ,,primed ,,siphon4 ,to carry a watercourse over a canal1 river1 road1 or railway1 several methods may be employed1 as1 for example1 by aqueducts like those of ,arcueil and ,buc near ,versailles1 and by upright and inverted siphons4 ,of these three means1 the first is the most imposing1 but is also very costly2 and1 besides1 the declivities as well as the arrangement of the ground are not always adapted thereto4 ,the inverted siphon is subject to obstruction and choking up in its most inaccessible parts1 while the upright siphon is easy of inspection1 taking apart1 etc4 ,but1 per contra1 the latter loses its priming very easily by reason of the formation of air spaces4 ,illustration3 ,,falconetti',s ,,siphon4 ,mr4 ,falconetti1 an inspector of bridges and roadways1 has found a means of rendering the latter occurrence impossible by an arrangement which is both simple and practical1 and which is illustrated herewith4 ,in the figure1 a and b are the two vertical legs of the siphon1 both of which enter the liquid4 ,these open into the receptacles1 c and d1 in which the cocks1 e and f1 cut off or set up a communication with the pipes1 a and b4 ,these latter are connected by a branch1 g1 which may be put in communication with a reservoir1 h1 that is divided into two superposed compartments by a partition1 i4 ,such communication may be established or cut off by a valve1 j1 maneuvered by a key1 k1 which traverses an aperture in the partition1 i4 ,another aperture1 m1 in this same partition serves to put the two parts of the reservoir1 h1 in communication1 and1 for this purpose1 is provided with a cock1 n1 which is easily maneuvered from the exterior4 ,the object of this arrangement of cocks and reservoir is to prevent the siphon from losing its priming through the possible presence in the transverse portion of a certain quantity of air or gas that might be given off by the water and accumulate in this place4 ,the compartment1 ,a1 of the reservoir1 h1 is designed for receiving the gases that collect in the top of the siphon1 while the upper compartment contains water for making a hydraulic joint1 and consequently preventing any re-entrance of air through the apertures in the partition1 i4 ,to prime the siphon1 we shut the cocks1 e and f1 open the valves1 j and m1 and pour in water until the whole affair 7siphon and reservoir7 is full2 then we close the cock1 m1 and open the three others4 ,the siphon thus becomes primed1 and begins to operate as soon as any water reaches one or the other of the lower receptacles4 ,as the cock1 j1 is constantly turned on during the operation of the siphon1 the air that has been able to accumulate in the lower compartment1 ,a1 of the reservoir1 h1 would finally unprime the siphon by intercepting communication between its two legs4 ,in order to prevent such a thing from occurring1 it suffices to expel the air1 from time to time1 that accumulates in the chamber1 ,a1 this being done1 without stopping the operation of the siphon1 as follows3 ,after closing the cock1 j1 water is poured into the reservoir1 and1 running down to the lower compartment1 drives out the air through the cock1 m4 ,this operation once effected1 it only remains to turn off the cock1 m1 again1 and open j in order to establish the normal operation4 ,as the chamber1 ,a1 is provided externally with a water gauge1 ,n1 it may be seen at a glance when it is necessary to maneuver the cocks in order to expel the air4 ,this system of siphon is evidently applicable to all sorts of liquids4 ,it may likewise undergo a few modifications in its construction2 for example1 the valve1 which in our engraving is placed over the siphon1 may be located at any distance from the apparatus1 although it should1 in all cases1 be in constant communication with it by means of a tube1 and be placed a little higher than the siphon4 ,it may then be put under cover and be kept constantly in sight1 thus greatly facilitating its surveillance4 ,as may be seen1 the essential peculiarity of this improvement consists in the very ingenious arrangement that permits of immersing the cocks in the liquid to make them perfectly tight1 it being necessary that they should be hermetically closed in order to prevent the entrance of air to the siphon4 ,everything leads to the belief1 then1 that if upright siphons have never been able to operate regularly1 it has been because no means have been known of expelling the air from the interior without letting air from the exterior enter at the same time4 ,the arrangement devised by ,mr4 ,falconetti gets over the difficulty in a very elegant manner4 ,it seems as if it would be called upon to render great services in the industries1 and it well merits the attention of engineers of roads and bridges1 and of contractors on public works4--,revue ,industrielle4 99 99 99 99 99 ,,the ,,weibel-,,piccard ,,system ,,of ,,evaporating ,,liquids4 ,in the industries1 there are often considerable quantities of liquid to be evaporated in order to concentrate it4 ,such evaporation is very often performed by burning fuel in sufficient quantity to furnish the liquid the heat necessary to convert it into steam4 ,this process is attended with a consumption of fuel such as to form a very important factor in the cost of the product to be obtained4 ,in order to vaporize1 at the pressure of the atmosphere1 #a kilogramme of water at #j1 #fcg heat units are required1 and of these1 #ajj are employed in raising the water from #j to #ajj and #ecg in converting the water at #ajj into steam at #ajj4 ,this second quantity is called the latent heat of the steam at #ajj4 ,the sum of the two quantities is called the total heat of the steam at #ajj4 ,the total heat of the steam remains nearly constant1 whatever be the temperature at which the vaporization occurred4 ,illustration3 ,,the ,,weibel-,,piccard ,,evaporation ,,apparatus4 ,in order to utilize the steam as a means of heating1 it is necessary to condense it1 that is to say1 to cause it to pass from the gaseous to a liquid state4 ,this conversion disengages as much heat as the passage from the liquid to the gaseous state had absorbed4 ,it results from this that if we could condense the steam that is given off by a liquid that we are vaporizing1 in contact with another liquid that it is also a question of vaporizing1 we should utilize all the heat contained in the steam that was being given off from the first4 ,this object can be practically attained by two means1 viz41 by 7#a7 putting the disengaged steam in contact with the sides of a vessel that contains a liquid colder than the one that produced it2 7#b7 by raising the temperature and pressure of the disengaged steam in order to condense it in contact with the sides of the vessel which contains the very liquid that has produced it4 ,the first of these means is realized in the apparatus called multiple acting1 that are at present so generally employed in sugar works4 ,the second means1 which permits of a greater saving in fuel being made than the other does1 is realized by compressing the disengaged steam4 ,this compression1 which raises the temperature and pressure of the steam1 permits of condensing the latter in contact with the vessel wherein it has been produced4 ,by such condensation we continuously restore to the liquid which is being vaporized the heat of the steam which it gives off4 ,this solution of the question1 which has been partially seen at different epochs1 has but recently made its way into the industries4 ,it is being operated at present with complete success at the salt works of ,france and ,switzerland1 at those of ,austria and ,prussia1 in the sugar of milk factories of ,france and ,switzerland1 and1 finally1 in #ahhb1 the first application of it in the sugar industry was made at ,pohrlitz1 in ,moravia4 ,the saving of fuel that has been made in these different applications has always been great4 ,we shall now1 for the sake of explaining the system1 give a brief description of the apparatus as used at the ,pohrlitz sugar works mentioned above4 ,these works treat #bee tons of beets per #bd hours1 and obtain #d1jjj hectoliters of juice1 which is reduced to about #a1jjj hectoliters of sirup4 ,up to the present1 the concentration has been effected in a double acting apparatus partly supplied by exhaust steam from the motive engines and partly by steam coming directly from the generators4 ,in order to diminish the consumption of direct steam1 these sugar works put in a ,weibel-,piccard apparatus designed to concentrate only a third of their juice1 or about #a1cej hectoliters per day4 ,this apparatus 7see engraving7 consists of a steam compressor1 #j4hce m4 in diameter1 actuated directly by a driving cylinder of #j4e m4 diameter and #j4h m4 stroke1 and of three evaporating boilers of the ordinary vertical tube type1 the first of which has a surface of #aej square meters1 the second #fj1 and the third #hj4 ,the steam1 at the ordinary pressure of the generators1 say #e atmospheres1 is taken from the connected generators of the works1 and is led to the driving cylinder1 where it expands and furnishes the power necessary to run the compressor4 ,it then escapes at a pressure of l4#d atmospheres and enters the intertubular space of the first evaporator4 ,the compressor sucks up the steam from the juice of the first evaporator 7which is boiling at the pressure of the atmosphere1 without vacuum or effective pressure71 compresses it to #a4d atmospheres1 and forces it likewise into the intertubular space4 ,the ebullition of the first evaporator1 then1 is kept up not only by the exhaust from the motive cylinder1 but also by the steam from the juice itself1 which has been rendered fit to serve as a heating steam by the pressure that it has undergone in the compressing cylinder4 ,in this first application of the new system to sugar making1 it became a question of ascertaining whether the advantage resulting from compression was of great importance1 and1 in the second place1 whether the apparatus could be run with certainty and ease4 ,in truth1 the applications of the system for some years past in other industries permitted a favorable result to be hoped for1 and the result turned out as was expected4 ,with this apparatus it has been found that the work furnished by one kilogramme of steam passing through the motive cylinder1 from a pressure of #e atmospheres to one of #a4d1 is sufficient to compress #b4e kilogrammes of steam taken from the juice1 led into the compressor at one atmosphere and escaping therefrom at #a4d4 ,in other words1 one kilogramme of motive steam is sufficient to convert into heating steam for the first evaporator #b4e kilogrammes of steam taken from the juice in this same evaporator4 ,besides1 this same kilogramme of motive steam produces three effects1 one in this same evaporator1 and the other two in the two succeeding ones4 ,the effect obtained1 then1 from one kilogramme of motive steam is1 in round numbers1 #e4e kilogrammes of steam removed from the juice4 ,it must not be forgotten that the motive steam was at the very moderate pressure of #d effective atmospheres4 ,had the use of steam at high pressure 7#g atmospheres for example7 been possible1 it is easy to conclude from the above results that more than #f kilogrammes of water would have been vaporized with one kilogramme of steam4 ,the results here cited were ascertained by accurately measuring the quantities of water of condensation from each evaporator1 they soon received1 moreover1 the most important of confirmations by the decrease in the general consumption of fuel by the generators which occurred after the new apparatus was set in operation4 ,the mean consumption of coal per #bd hours for the twenty days preceding the #ahth of ,november was #hf1jfj kilogrammes4 ,after this date the regular consumption was as follows3 ,nov4 #ai44444444444444444ca1hjj kilogrammes4 #bj44444444444444444cc1hjj #ba44444444444444444cc1hjj #bb44444444444444444cb1jjj #bc44444444444444444ca1djj #bd44444444444444444ca1fjj #be44444444444444444cj1ejj #bf44444444444444444cj1ejj #bg44444444444444444bh1fjj #bh44444444444444444cj1cjj ,it must be remarked that in the perfectly regular running of the sugar works1 nothing was changed saving the setting of this evaporating apparatus running4 ,the same quantity of beets was treated per #bd hours1 and the general temperature remained the same4 ,this remarkable result in the saving of fuel was brought about notwithstanding the new apparatus treated but a third1 at the most1 of the total amount of the juice1 the rest continuing to be concentrated by the double action process4 ,as for the running of the apparatus1 that was perfectly regular1 and the deviations in temperature in each evaporater were scarcely two or three degrees4 ,the following are the mean temperatures3 ,first evaporator3 heating steam #aaj ,c42 juice steam #ajj ,c4 ,second evaporator3 juice steam #hc ,c4 ,third evaporator3 juice steam #fb ,c4 ,as regards facility of operating the apparatus1 the experiment has proved so conclusive that the plant will be considerably enlarged in view of the coming crop1 in order that a larger quantity of juice may be treated by the new process4 ,the effect of this will be to still further increase the saving in coal that has already been effected by the present apparatus4 ,the engraving which accompanies this article represents the ,weibel-,piccard apparatus as it is now working in the ,pohrlitz sugar works4 ,what we have said of it above we think will suffice to make it understood without further explanation4--,le ,genie ,civil4 99 99 99 99 99 ,,comparison ,,of ,,strength ,,of ,,large ,,and ,,small ,,animals4 ,w4 ,n4 ,,lockington4 ,m4 ,delebeuf1 in a paper read before the ,academie ,royale de ,belgique1 and published in the ,revue ,scientique1 reviews the attempts of various naturalists to make comparisons between the strength of large animals and that of small ones1 especially insects1 and shows that ignorance or forgetfulness of physical laws vitiates all their conclusions4 ,after a plea for the idea without which the fact is barren1 ,m4 ,delbeuf repeats certain statements with which readers of modern zoological science are tolerably familiar1 such as the following3 ,a flea can jump two hundred times its length2 therefore a horse1 were its strength proportioned to its weight1 could leap the ,rocky ,mountains1 and a whale could spring two hundred leagues in height4 ,an ,amazon ant walks about eight feet per minute1 but if the progress of a human ,amazon were proportioned to her larger size1 she could stride over eight leagues in an hour2 and if proportioned to her greater weight1 she would make the circuit of the globe in about twelve minutes4 ,this seems greatly to the advantage of the insect4 ,what weak creatures vertebrates must be1 is the impression conveyed4 ,but the work increases as the weight4 ,in springing1 walking1 swimming1 or any other activity1 the force employed has first to overcome the weight of the body4 ,a man can easily bound a height of two feet1 and he weighs as much as a hundred thousand grasshoppers1 while a hundred thousand grasshoppers could leap no higher than one--say a foot4 ,this shows that the vertebrate has the advantage4 ,a man represents the volume of fifteen millions of ants1 yet can easily move more than three hundred feet a minute1 a comparison which gives him forty times more power1 bulk for bulk1 than the ant possesses4 ,yet were all the conditions compared1 something like equality would probably be the result4 ,much of the force of a moving man is lost from the inequalities of the way4 ,his body1 supported on two points only when at rest1 oscillates like a pendulum from one to the other as he moves4 ,the ant crawls close to the ground1 and has only a small part of the body unsupported at once4 ,this economizes force at each step1 but on the other hand multiplies the number of steps so greatly1 since the smallest irregularity of the surface is a hill to a crawling creature1 that the total loss of force is perhaps greater1 since it has to slightly raise its body a thousand times or so to clear a space spanned by a man's one step4 ,by what peculiarity of our minds do we seem to expect the speed of an animal to be in proportion to its size8 ,we do not expect a caravan to move faster than a single horseman1 nor an eight hundred pound shot to move twelve thousand eight hundred times farther than an ounce ball4 ,devout writers speak of a wise provision of ,nature4 ,if1 say they1 the speed of a mouse were as much less than that of a horse as its body is smaller1 it would take two steps per second1 and be caught at once4 ,would not ,nature have done better for the mouse had she suppressed the cat8 ,is it not a fact that small animals often owe their escape to their want of swiftness1 which enables them to change their direction readily8 ,a man can easily overtake a mouse in a straight run1 but the ready change of direction baffles him4 ,m4 ,plateau has experimented on the strength of insects1 and the facts are unassailable4 ,he has harnessed carabi1 necrophori1 ,june-beetles 7,melolontha71 and other insects in such a way that1 with a delicate balance1 he can measure their powers of draught4 ,he announces the result that the smallest insects are the strongest proportioned to their size1 but that all are enormously strong when compared bulk1 for bulk1 with vertebrates4 ,a horse can scarcely lift two-thirds of its own weight1 while one small species of ,june-beetle can lift sixty-six times its weight2 forty thousand such ,june-beetles could lift as much as a draught-horse4 ,were our strength in proportion to this1 we could play with weights equal to ten times that of a horse4 ,this seems1 again1 great kindness in ,nature to the smaller animal4 ,but all these calculations leave out the elementary mechanical law3 ,what is gained in power is lost in time4 ,the elevation of a ton to a given height represents an expenditure of an equal amount of force1 whether the labor is performed by flea1 man1 or horse4 ,time supplies lack of strength4 ,we can move as much as a horse by taking more time1 and can choose two methods--either to divide the load or use a lever or a pulley4 ,if a horse moves half its own weight three feet in a second1 while a ,june-beetle needs a hundred seconds to convey fifty times its weight an equal distance1 the two animals perform equal work proportioned to their weights4 ,true1 the cockchafer can hold fourteen times its weight in equilibrium 7one small ,june-beetle sixty-six times71 while a horse cannot balance nearly his own weight4 ,but this does not measure the amount of oscillatory motion induced by the respective pulls4 ,for this1 both should operate against a spring4 ,a small beetle can escape from under a piece of cardboard a hundred times its weight4 ,pushing its head under the edge and using it as a lever1 it straightens itself on its legs and moves the board just a little1 but enough to escape4 ,of course1 we know a horse would be powerless to escape from a load a hundred times its own weight4 ,his head cannot be made into a lever4 ,give him a lever that will make the time he takes equal to that taken by the insect1 and he will throw off the load at a touch4 ,the fact is that in small creatures the lack of muscular energy is replaced by time4 ,of two muscles equal in bulk and energy the shortest moves most weight4 ,if a muscular fiber ten inches in length can move a given weight five inches1 ten fibers one inch long will move ten times that weight a distance of half an inch4 ,thus smaller muscles have an absolutely slower motion1 but move a greater proportional weight than larger4 ,the experimenter before mentioned was surprised to find that two grasshoppers1 one of which was three times the bulk of the other1 leaped an equal height4 ,this was what might be expected of two animals similarly constructed4 ,the spring was proportioned to the bulk4 ,in experiments on the insects with powerful wings1 such as bees1 flies1 dragon-flies1 etc41 it was found that the weight they could bear without being forced to descend was in most cases equal to their own4 ,in some cases it was more1 but the inequality of rate of flight1 had it been taken into the reckoning1 would have accounted for this4 ,take two creatures of different bulk but built upon exactly the same plan and proportions1 say a ,brobdingnagian and a ,lilliputian1 and let both show their powers in the arena4 ,suppose the first to weigh a million times more than the second4 ,if the giant could raise to his shoulder1 some thirty-five feet from the ground1 a weight twenty thousand pounds1 the dwarf can raise to his shoulder1 not1 as might be thought1 a fiftieth of a pound1 but two full pounds4 ,the distance raised would be a hundred times less4 ,in a race the ,lilliputian1 with a hundred skips a second1 will travel an equal distance with the giant1 who would take but a skip in a second4 ,the leg of the latter weighs a million times the most1 but has only ten thousand times as many muscle fibers1 each a hundred times longer than those of the dwarf1 who thus takes one hundred skips while the giant takes one4 ,the same physical laws apply to all muscles1 so that1 when all the factors are considered1 muscles of the same quality have equal power4--,am4 ,field44 99 99 99 99 99 ,,oil ,,in ,,california4 ,j4,w4 ,mc,kinley1 writing to the ,pittsburg ,dispatch1 gives the following account of the ,california oil field at ,newhall3 ,on the edge of the town is located the refinery of the company1 connected by pipe lines with the wells1 a few miles distant4 ,leaving ,newhall1 we drove to ,pico ,caon1 the principal producing territory of the region4 ,as we approached1 we saw1 away up on the peaks1 the tall derricks in places which looked inaccessible2 but no spot is out of reach of ,american enterprise and perseverance4 ,in one of the wildest spots of the caon1 about thirty men were making the mountains echo to the strokes of their hammers upon the iron plates of a new #bj1jjj barrel tank4 ,along the caon are scattered the houses of the employes of the company1 most of whom have recently come from ,pennsylvania4 ,near one of the houses was a graded and leveled croquet ground1 with a little oil tank on a post1 for lighting it at night4 ,farther up we came to a cluster of producing wells1 with others at a little distance on the sides of the mountains1 or even at the top1 hundreds of feet above our heads4 ,the first well was put down about eight years ago1 but more has been accomplished in the last two years than in all the time previous4 ,one well which we visited has produced #acj1jjj barrels in the last three years1 and is still yielding4 ,there have been no very large wells1 the best being #bej per day1 and the average being about #ij barrels1 but they keep up their production1 with scarcely any diminution from year to year4 ,drilling has been found difficult1 as a great portion of the rock is broken shale lying obliquely4 ,the tools slip to one side very easily1 and a number of crooked holes have resulted4 ,one driller lost his tools altogether in a well1 and finished it with new ones4 ,the cost of putting down a well is from #e1jjj to #g1jjj1 depending upon depth1 etc4 ,most of the wells are from #a1bjj to #a1ejj feet1 but some have yielded at a much less depth4 ,one well of #bgj feet depth produced #dj barrels per day for about three years1 has been deepened1 and is now yielding even more4 ,another one of #hjj feet is said to have produced #bjj1jjj barrels in the last five or six years4 ,drilling has been very successful in striking oil in paying quantities wherever there were indications of its presence4 ,the ,pacific ,oil ,company now has #bg wells producing or drilling1 and during the last two years has been rapidly widening the scope of its operations4 ,it has now from #cj to #dj miles of pipe lines1 and is preparing to lay #bj miles more1 to connect its land with ocean shipping at ,ventura4 ,the producers of ,california have a great advantage in their proximity to the ocean1 which gives them free commerce with the outside world4 ,crude oil is now sold at #c per barrel in ,los ,angeles1 and the oil companies are making immense profits4 ,there is a very large amount of oil territory as yet undeveloped1 and a rich reward awaits enterprise in these regions4 ,in the ,camulos ,district1 which lies west of the ,san ,fernando1 are even stronger surface indications of oil than there were in the ,pico ,caon4 ,we first went up the ,brea ,caon1 in which are numerous outbursts and springs of oil4 ,ascending the mountain west of this caon1 we could plainly see the break in the mountains crossing from the ,san ,fernando through this district to those beyond which have been developed4 ,a couple of miles farther west1 the ,hooper ,caon stretches back over two miles into the mountain1 and is full of oil4 ,great pools of oil fill its water courses1 that are dry at present4 ,hundreds of barrels of oil must be wasted away and evaporated during a year4 ,a well put down only #ij feet by horse power1 struck light oil in considerable quantity1 and1 had it not been for the death of one of the owners and the consequent suspension of operations1 would doubtless have yielded in large quantities at the depth of a few hundred feet4 ,the mountainous territory between these two caons will probably in a few years be the scene of great activity4 ,in the ,little ,sespe ,district1 a few miles west of ,camulos1 a #abe barrel well was struck at #a1ejj feet recently4 ,the ,santa ,paula region1 a little farther west1 is also yielding large profits to the parties developing it4 99 99 99 99 99 ,,nutritive ,,value ,,of ,,condiments4 ,by ,,helen ,d4 ,,abbott1 ,assistant in the ,chemical ,laboratory of the ,philadelphia ,polyclinic1 and ,college for ,graduates in ,medicine4 ,the prevailing opinion respecting the substances known as condiments is1 that they possess essentially stimulating qualities1 rendering them peculiarly fitted for inducing1 by reflex action1 the secretion of the alimentary juices4 ,letheby gives1 as the functions of condiments1 such as pepper1 mustard1 spices1 pot-herbs1 etc41 that besides their stimulating properties they give flavor to food2 and by them indifferent food is made palatable1 and its digestion accelerated4 ,he enumerates as aids to digestion--proper selection of food1 according to the taste of the individual1 proper treatment of it as regards cooking1 and proper variation of it1 both as to its nature and treatment4 ,while it is difficult to give an entirely satisfactory definition as to what constitutes food1 the following extracts from standard works will serve as guides4 ,hermann#a says3 ,the compound must be fit for absorption into the blood or chyle1 either directly1 or after preparation by the processes of digestion1 i4e41 it must be digestible4 ,it must replace directly some inorganic or organic constituent of the body2 or it must undergo conversion into such a constituent1 while in the body2 or it must serve as an ingredient in the construction of such a constituent4 ,he further says that water1 chlorides1 and phosphates are the most indispensable articles of diet4 ,watts#b states that whatever is commonly absorbed in a state of health is perhaps the best1 or rather the truest1 definition of food4 ,footnote #a3 ,elements of ,human ,physiology1 by ,l4 ,hermann4 ,translated by ,gamgee4 ,footnote #b3 ,dictionary of ,chemistry1 vol4 iv41 pages #adg-h4 ,chemical analysis shows that the most important and widely applicable foods contain carbon1 hydrogen1 oxygen1 nitrogen1 and mineral matter1 the latter containing phosphates and chlorides4 ,other things being equal1 it may be considered that the comparative nutrient value of two articles is in proportion to the amounts of carbon1 nitrogen1 and phosphoric acid they contain4 ,the food of man also contains certain substances known under the name of condiments4 ,since these bodies perform their functions outside the real body1 though within the alimentary canal1 they have no better reason to be considered as food than has hunger1 optimum condimentum4#a ,such is the positively expressed opinion of ,foster1 the author of the article on nutrition in ,watts' ,dictionary of ,chemistry4 ,with a view of determining how far the common condiments deserve this summary dismissal1 a number of analyses have been made in the laboratory of the ,philadelphia ,polyclinic4 ,my examinations were especially directed to the mineral matter1 phosphoric acid1 and nitrogen4 ,the following table shows the result of the analyses3 ,percent4 ,percent4 of ash4 of ,p#b,o#e4 ,fennel444444444444444444444444 #i4jj 4#ajc ,marjoram4444444444444444444444 #h4hd 4#jej ,peppermint44444444444444444444 #h4hj 4#jaf ,thyme4444444444444444444444444 #h4cd 4#abb ,poppy4444444444444444444444444 #g4gd 4#jbd ,sage44444444444444444444444444 #g4eh 4#jcc ,caraway44444444444444444444444 #g4jh 4#aah ,spearmint444444444444444444444 #g4jf 4#jag ,coriander444444444444444444444 #f4aj 4#jig ,cloves444444444444444444444444 #e4hd 4#efc ,allspice4444444444444444444444 #e4ed 4#jag ,mustard44444444444444444444444 #c4ij 4#acd ,black pepper444444444444444444 #c4fj 4#jaa ,jamaica ginger4444444444444444 #c4af 4#jeb ,cinnamon4444444444444444444444 #c4jb 4#jji ,mace44444444444444444444444444 #b4dd 4#bcj ,nutmeg444444444444444444444444 #b4bd 4#jib ,celery444444444444444444444444 #a4bi 4#jhb ,white pepper444444444444444444 #a4af 4#jag ,aniseed44444444444444444444444 #a4je 4#aac ,footnote #a3 ,ibid41 page #adi4 ,the articles were examined in the condition in which they were obtained in the market1 without any preliminary drying1 selecting1 or preparation4 ,the ash was obtained by burning in a platinum crucible1 at as low a temperature as possible1 dissolving in hydrochloric acid the phosphoric acid separated as ammonium molybdo-phosphate1 and determined in the usual manner4 ,qualitative tests made for nitrogen indicated its presence in each one of the condiments examined4 ,it is of importance to observe that the majority of these condiments are fruits1 ripe or nearly so4 ,the seed appropriates to itself the nitrogen and the greatest nutritive properties for the development of the future plant4 ,all nutritive substances fall into two classes3 the one serves for the repair of the unoxidizable constituents of the body1 the other is destined to replace the oxidizable4 ,condiments fulfill both of these requirements1 as is shown by a study of their composition2 the phosphoric acid and nitrogen are taken up by the tissues1 as from other substances used in diet4 ,some articles affect the character of the excretions2 this is often due to essential oils2 the presence of these in the excretions cannot be said to diminish the value of the substances in supplying the tissues the necessary elements4 ,the same holds true for condiments2 the essential oils conspicuous in them are accorded only stimulating properties2 however1 it may be observed that the essential oils in tea and coffee are accredited with a portion of the dietetic value of these beverages4 ,it appears that when condiments are used in food1 especially for the sick1 they may serve the double purpose of rendering the food more appetizing and of adding to its nutritive value4 ,the value of food as a purely therapeutic agent is attracting some attention at present1 and in its study we must not neglect those substances which combine stimulant and nutritive qualities4--,polyclinic4 99 99 99 99 99 ,a catalogue1 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 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,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 ,caveats4 ,trade ,marks1 their costs1 and how procured1 with hints for procuring advances on inventions4 ,address ,,munn ,,co41 #bfa ,,broadway1 ,,new ,,york4 ,branch ,office1 cor4 ,f and #gth ,sts41 ,washington1 ,d4 ,c4