Volume 29 (1874) (428 pages)

August 1, 1874.] MINING AND SCIENTIFIC PRESS. 67 I ECHANICAL Procress Tin Plates. From a paper recently read by Mr. Speakmaa, of Philadelphia, we obtain the following description of how tin plates. aro made; . After tho sheets are cut down to eize for tinniog they are separated from each other by what is called opeuing; during the progese of opeoing “‘stickers’’and imperfect platos are thrown oat, and the paesed eheets then go into the pickling room. There they are put into o hot pickle of dilute sulpharie acid, to he cleansed from oxidized and silicinus matters, and undorgo auother rough examiuation in the scoaring process; that is, any plate not cleansed is rabbed with sand in water. Defectivoshecta are again thrown out, and the plates are now passed into tho annealing room. The plates are carefully annealed and are thon sabmitted to a hot but more dilute picklo of sulpharie acid, and again chemioally cleansed ; taken from the acid bath they aro woll washed in running wator, and keptia clean water untal tho tinman is ready for them. The tinman takes tho plates from the waterbath (whero they lie some hours) and plunges them wet into a hath of hot palm oil, called the "grease-pot.”” When they have acquired the temperature of the grease-pot, they are removed with tongs and quickly submerged in a bath of tin. The oil mixed with the water from the plates floats at the top, forming a fiux which covors the melted tiu and prevents oxidation. With the tongs, the sheets or plates are continually kept moving and separated, to insure the tia gettlng between all of the sheets. When the bath has recovered its heat, which it genorally does in about half ant hoar, the tinman examines the charge, and ifhe finds that perfect amalgamation hae taken plsce hetween the two metals, he removes them witha tongs to the next hath, whichis kept at a low ‘temperature. The temperatnre raised by the change from the “tin-pot’’is again allowed to cool down to a few degrees over the melting point of the tin, when the platesare taken in lots af a dozen or . . two at a time, and laid an‘an iron slab which is at the side or head of the pot. The waste metal and grease run back into the pot, the slab being inclined, The workman thon takes up sheet by shoet with the tongs, and dips each into anothor hath of fine meta} kept at a heat a little over melting point, immediately withdraws it, and places it in a rack immorsed in a large pot of melted palm oil kept at the proper tempersture, where they are allowed to remsin neertain time. The eheets are then slowly lifted out of the grease by a boy, who separates them into proper lote by counting carefully, regulating the intervals of time hetween them. The grease recoils from the top plate, and, as Tittle is left on the sheets, they are again placed in a rack in the open air to 0001; when cool a lad takes each sheet iu a tongs, and dips the lower edge into 2 small bath of melted tin so regulated that the sheet can only enter to about the eighth of aniuch. Itis kept long enough to ari off the drops of metal which adhere to the lower edge, and when lifted the sheet is struck to throw off the superfinous metal from the edge. The plates are again putinto a rack, and taken while warm toa hin of bran, where each sheet is thrust into aud under the bran, to get rid’of the grease which adheres. It is’ then passed oa to a second and third hana, when the greaseis pretty well behind in the last bin, which is kept filled with new bran, The sheets are turned out covered with flour dust and bran, and dusted off with cotton shaggy cloth. The next process is in the sorting room. Here the finished sheets are laid on tables, and each sheet undergoes an examination by the sorter, who throwa ont those shearings which are defeotive in the iron or trimminge. The latter are reheated to regain the tin; the imperfeot sheets are sold as ‘*wasters” ata less price; the sheets are counted, and the box of 100 Ib.weight is composed of 225 sheote of 14inohes by 10 inohes, for home nse or exportation. New Barrisa Steet Gons.—For some speoinl purposes a very light arm is required, as, for instance, where field-gnns have to be carried over mountainons country, as also for arming the steam launches and pinuaces cartied by iron-clads, and it is to supply this want that the steel weapons have been designed. They weigh but two hundred pounds each, and can, therefore, he carried on a mule,.or in the pra of a boat, without incouvenience. Being ored and fashioned from a single block of steel, the utmost strength, has heen obtained, the weapons being, moreover, tempered in oil to harden them as mach as poasible, after attaining to the proper caliber. The.hore of the gun is thirty-six inches long, and the diameter of the projectile that it firee is four inches. ‘The utmost range of the new arms is etated to be four thousand yards, Up to n recent date, the Westinghouse brake has been under the exclueiye coutrol of the engineer, now it can be applied to the entire train by any person in any car; while the train, in case of derailment, also appliee the. brake to itself, adding an immense impeding force to the obstacles which it otherwise encountere. = In Maine, the building of three masted echoonere is increasing. These yeesele are, on the Atlantic coast, fast superseding other kinds of vessels, They are built cheaper, consequéntly. thére is more profitin their oonetruction, *’ ‘showed great power in grappling with a diffiTransmission of Power by Wire Ropes. At a meeting of the Institution of Mochasical Engineers, London, Mr. Morrisou descrihed the mode of transmission iatrodaced hy the Bros. Hirn, aud now extensivoly ased on the Upper Rhine, It appeared that they first nsed flat metallic hands to transmit the power; but, these heing found ohjectInuablo, ronnd wiro rope was sabseqaently adopted, instead. The rope is usually made of fiac stoel wiro, as it must he very tough and flexihle, The wire rope, which is about one inch in diameter, aud cantains 72 strsnds, is rou st a high velocity, over pulloys of large diameter. The total loss of power by friction, ote., was stated to be 2% per ovnt., and it appeared that, of 120 horee power existing at the motor wheel, 100 horse power was ntilized at 2,200 yards distance; but it could not he elicited in the discussion how these figures had been arrived at. It was alao estlmated that iron shafting, capable of transmitting the same power, woald invulve the use of 3,000 tons of material. Various materials were tried for facing the grooves of the pulleys, éuch as copper, leather, eto., as there either was excessive wear in the groove, or the facing destroyed the rope. The best arrangement was found to be a dovetail groove, filled in with gutta-percha, in which the rope soon made a channel for itself, after which the wear was not excessive. The pulleys run at the rate of 50 miles per hour, and the ropes last from one and a-half to two years. Dr. Siemens remarked that there was no doubt that, by running ropes from 30 to 60 molles per hour over palleys, a large amount of power could be tranemitted with but little waste, Mr. Wm, Smith said that in 1837, soon after his father had invented wire rope, it was used very similarly, and in 1839 and 1840 it was introduced on the Regent’s canal, for towing barges through the tnnnel beneath the Herrow road, and it was also taken three and a-half or four miles along the bank of the canal, The bargeman simply threw a catch line over the Tunning wire, and let go when necessary. It was toeted against the screw, duck-foot propeller and others, but was not found to be economic. He had many times seen a similar application of the principle; the fiy-rope of an ordinary’ ropery wes an illustration, but that had long eince been obsolete. He would like to know whether the paper claimed, as. a . novelty, the introduction of endless wire ropes for transmitting power to a distance; if so, he doubted whether the olaim could be substantiated. If the novelty merely consisted in the runaing of the ropes at a high velocity, which was all he could see in it, there might he something in the claim. * Castino Igon rn SAND Mntps,—In Fairbairn’s Tron Manufacturer we find the following account of the first sucoessful attempt in England to run cast-iron in molds of sand: In 1706, John Darby, one of the four partners of the brass worke known as Beptist Mills, at Bristol, England, conceived the idea that cast-iron might be substituted for brass, and prevailed upon some of the workmen to try and mske iron castings in molds; but they failed, and considerable loss was incurred in théir experimeut. A young Welsh apprentice, who had been a shepherd-boy,’camo into the employ of the Darbys. As he was looking. on during the trial of the Dutch workmen to cast iron, he said to Abraham Darhy that he thought he saw how they had missed it. He begged to be allowed to try, nnd he and Abraham Darhy remained alone in the workshop, the’ same night for the purpose, Before morning they had cast an iron pot. The boy Thomas entered into 6n agreement to serve Ahraham Darby and keep the secret. For more than 100 yeargafter. the night in which Thomas and his master. made their suocessful experiment of producingan iron casting in a mold of fine saud, with its two wooden frames and ‘its air holes, the same process was practiced and kept secret at Colebrook Dale, with plugged key holee and barred‘ doore. % ' &@ paper On coal-cutting machines, read at; Bradford, hy Mr. Firth, mention was made of the extraordinary power of these machines in dispensiug with hand labor, One man, a youth, a boy and a machine, oan compaasa the' work of twelve men, thue reducing ‘‘that hard physical ‘labor ’' by seventy-five per cent. Mnureover, the machine in nse at Ardsley cult seam, aud reduoed the cost of production by Is. 7d. perton. The rapid introduction of coal-cutters seems to promise a revolution in the coal trade, and will doubtless present’an additional indncement to the many capitalists whn are now devoting their energy and their cash to the opening-up of new pits.—English Exchange. ef ok Tue smallest eteam engine on record was made hy a Scotchman, nnmed Crawford. It is, perfect in every part and so small that it can be covered by a lady’s thimble. It can be worked by steam, but he nsually works it by atmospherio pressure, through a flexible tuhe, with rubher airreceiver. The pet éngine was made a8 4n amusement, and to ehow what could he done. It is undoubtedly the emallest working maohine ever made. _Sroprrno Borrnre.—A new invention consiste in attaching india-rubber tubing to the neck of the bottle, said tube being bent over and se. being oarried off.;. The movement of a glacier Coat-currino Maontnes.—In the course of . ° ‘fluids, and that a body ie electrified positively lor Negatively, ‘according #8 one or the other of ‘these'is in ‘excesy. According to Dr, Frankoured in that position to close the neok of the bottle, e yy ACIENTIFIC (Procress. » Remarkable Motive Power. A curioas capillary experiment was devised by M. Lippmann some months since, which the author has recently utilizedin a very ingenious way, The original experiment is thus deserihed: Place in a saucer orina large wateh-glsss a glohtile of mercury and inch or two in diame. ter, and pour upon it a little water acidalated with sulphuric acid and slightly oolored with potassium hichromate. If now the mercury he touched laterally with the point of a needle, the globule will bo observed to contract and withdraw itself from the needle, then to extend again to its primitive position. This brings it again into contact with the needle, the oontraetion is renewed, aud so on indefinitely, When the globule is qaite large it executes oontorted and grotesque movements which are surprising to those who aro not in the scoret. The explanation of this phenomenon is found in the fact that under the joint inflaence of the iron and the hichromate, the mercury is sucoessively oxidized and deoxidlzed, thereby producing an alteration in its oapillary condition and causing the swelling aud flattening, Thie oxidation and deoxidation may also he effected ‘by an electrio current. The globule is seen to swell up or to flatten, according as it is connected with the negative and deoxidizing or with the positive and oxidizing electrode. It is: this oscillating motion of the globule of mercury that M. Lippmann has utilized ia his: motor. It is constructed as follows: In a trough of glass two small oups are placed, full of mercary; in each of these moves a pistou formed of s bundle of glass tabes. The trongh is filled with acidulated water, and the two masses of meroury are in communication with the electrodes of a battery in such a way that when the one contraots the other flattens, Consequently, when one of the pistons rises the other falls; and hy simply transforming this reciprocating motion of the pistons intn a rotary one, an electro-capillary engine of some hnndredthe of a kilogram-metre of poweris readily obtained. Inthe maohine actaally constructed by M. Lippmann the fiywheel made a hundred revolutions per minute. The extremely feehle current needed to set thie engine in action suggests its mse ae an indicstor of currents too teeble'to be detected by ordinary instruments. Used in this way it would constitute an extremely sensitive electrometer. Indeed it might come in use for the ‘reception of cahle dispatches, which, as is well known, are sent by meaus of very feeble currents, Certain movements of the maohine might correspond to certain predetermined characters or eentences, and in; this way the dispatch might he easily deciphered. Though sourcely more than curious at present, theer exAtmospheric Dust. Among the conclastoue reached by Mr. Cunningham, of Caloutta, in an elaborate series of microscopical examinations of atmospheric dust, are the folowing: ireemeei Specimens of dast washed from exposed stirfaces cannot be regsrded as fair indices of the constituents of atmospherio dust, since they are liable to contain Bodies whioh may have reached the surfsoe otherwise thsn by means of the air, as well ae others which are the result of local development. Specimens collected by gravitation also fail to indicate the nature and amoant of organio cells contained in the atmosphere, as ths heayler amorphous and inorganio constituents of the dust are deposited in relative exoese due to the method of collection. Dew also tails to afford a good meane af inveatigating tho sabject, as it is impossible to secnre that sll the hodies really present in a specimen of it should he collected in a sufficiently small space, and, moreover, becaues it is liable to accldental oontaminatione, and also affords 2 medium in which rapid growth and development are likely to take place. Spores snd other vegetable oells are constantly present in atmospherio dust, and usually oconr 1n considerable numbers; the majority of them are capshle of growth snd development; the amount of them ‘present in the air appeare to he independent of conditions of velocity and direction of wind; and their numbera are not diminished by moisture. The amount of inorganio and amorphous particles and other debris euspended in the atmosphere is direotly dependent on conditions of Moistare and of velocity of wind. New Expuostve.—An English inventor has taken out a pateat for improvements in explosive compounds, in which he usee sawdust, Spent tan, etc., freed from impurities, and submerged for a few moments ia nitrio or sulphuric scid, and mixed with certain nitrates. ‘The tan, ete., when prepared, is termed the wet incipient componnd, and to form explosive compound No. 1, 40 lb. of this is mixed with 60 Ih. Of nitrate of baryta, ammonia, lead or stroutium. To thie mixture ia added 6 lb. of nitro-glacerine, ahsorhed by fine dry eand or infusorial earth, 20 1b, of soft wood charcoal or coal, 10 lb. of chlorate of potash, and 5 lb. of sulphur. The whole is then dried at a temperature of about 90 deg. to 100 deg. Fah. For compound No. 2, 57 lb. of spent tan are mixed with a hoiling saturated solution of nitrate of baryts, soda, eto., 15 lh. -of sulphur,.and 6 Ib. of chlorate of potash, and dried-at about 212 deg. Fah. Compound No. 3 contains 70 lbs of nitrate of baryta, 12 Ib. of anthraoite, sea-coal or soft wood charcoal, 7 lb. af nitrateof potash, 6 lh. of loaf sugsr, 6 lb. of sulphur and 2 Ib. of chlorate of potash, first crunched and then mixed together. The mixture is then damped periments of M. Lippmann are exceedingly in-. With ordinary glyoerine, sufficient to niake its teresting, and will undoubtedly in the future) Various parts cohero, and dried at about 212 receive Important applioations.—Journal of Frantlin Inst. : Cray Guactens.—The gliding masses of clay, resembling glaciete in many: respects, which are to be seen in the velloys Of the Apennines, form the suhject of a memoir communicated to the French Geological Society by’-M. de Mortillet. These mountains oonsist of sandstone, sand and olay. The clays retain water like a sponge, and hedoming saturated, take the form of a sort of slippery dough. Then they slide and move hke glaciers; the pressure on the olay as it glides along the sides of the yalley; causes the calcareous debris to rise-to the surface, which gives the moving ‘mass a further resemblatice to a glacier. iatéral’ moraines, too, are formed, and along the sides of the vslley is fonnd a great accumulation of oalcareous fragmente. ~The pressure~exerted hy these masses is enormous. M. de Mortillet mentions railway embankinents of solid construction being swept away by them, the gravelly stratum on which the émhankments wereoonstracted is due solely to the pressure of the higher portons of it upon the lower, and its’ progress is in proportion to the weight of the mass abové.Glaciers are plastio, it is true, but they can not be eaidto flow. .; i : oe Nature or Execrsicrry. — Attempts haye beeu'made to combine the wave théory of light and electricity by supposing that the vibrations of the ether which produce the phenomena of ‘electricity are longitudinal, reeembliug: those of sonnd, while’the phenomena of light Are produced : hy transverse vibrations of the same medium. Another theory which has'been long believed, is that’ eleotriclty consists of two lin’s theory, there is a'single fiuid and ‘the phenomena depend upon the’ excess or’ deficiency of this fluid. Ahout three yeare' ago, Professor Edlung read 2 paper béfore the Swedish Academy, in which he advanced the theory thst this single fluid was the ether’ by:whose vibratione light is produced; a‘ body heing charged positively when it cantains an ‘excess of ether, and negatively when the ether ie defi‘cient. 7, wi Svoar Contarnep In Vine Leaves,—Petit, the author,’ finds that grape leaves contain from 20 to 30 grme. of glucose per kilogramme, and from 13 tn 16 grms, of acid; of which’ one‘. tation, eg. Fah, Gas Pressors AuarM.—When two neigh. boring buildings are illumiusted by gas @srived -from the same source, it frequently happens ‘that the extinction of the lights in one building causes the pressure of gas in-the other-to become greatly increased, and sometimes to re-ault in accident. M. Launay -proposes, -as an .2lsrm to give warning of this over-preseure, a -bisulphate of mercury battery, in whioh the Nquid is in communication with the gas by . means of 8 siphon, eo that the pressure of the pas in varying, rsises or lowers ite level. If its pressure is above a certain fixed limit, the liquid is raised so as to come in contact with the metallio portion of the battery, establishi a current which eounds an electrio alarm. : Lsunay also suggests that a simple method of determining leaks in gas pipes throughout a building is to force some strongly .odorous smoke into the supply pipe. The fumes of Inoense, for example, escaping in any room, would be readily distinguished from gas, and the locality of the leak quickly foand. +. Cutnese Mrrzors. — The curious property posseseed hy Chineso metal mirrors of reflecting figures put upon the hack by way of ornamenas long heen a matter of wonder to persons igaorant of the reasons for the phenomenon. Their manufacture is described as follows: Chinese mirrors are castings of a somewhat porous alloy, Before the reflecting face is finally polished, itis laid on an anvil, and the embossed designe or figures at the baok well hammered. This, of coarse, condenses and closes the pores of the metal in these parts, and, in consequence, when the face is finally polished, the metal in front of the design has its power of reflecting light inoreased, and so gives rise to the fallacious idea that the pattern shines through the metal. VasELINE.—The new product of petroleum to which this name has been given promiees to come into use as a vehicle for various emollient preparations, for which it appéare to possees some peculiar advantages. It iea-eolid, semitransparent jelly, neutral, and free from taste or odor, and it is eaid to undergo no change by keeping. It hecomea liquid at a temperature of 95° Fshr. The manufacturers state that it is prepared simply by the evapcration of crude petroleum, and filteriag the residue-through ahimal nharcoal. oy .M. Bertuenor has recently succeeded in third ie tartario acid, mosily existing ag bitartrate of potash. Grape leavee contain eate. sugar as well as glucose, producing nitrite of an:monia for the first time in a oryetalline etate.

August 1, 1874.] MINING AND SCIENTIFIC PRESS. 67 I ECHANICAL Procress Tin Plates. From a paper recently read by Mr. Speakmaa, of Philadelphia, we obtain the following description of how tin plates. aro made; . After tho sheets are cut down to eize for tinniog they are separated from each other by what is called opeuing; during the progese of opeoing “‘stickers’’and imperfect platos are thrown oat, and the paesed eheets then go into the pickling room. There they are put into o hot pickle of dilute sulpharie acid, to he cleansed from oxidized and silicinus matters, and undorgo auother rough examiuation in the scoaring process; that is, any plate not cleansed is rabbed with sand in water. Defectivoshecta are again thrown out, and the plates are now passed into tho annealing room. The plates are carefully annealed and are thon sabmitted to a hot but more dilute picklo of sulpharie acid, and again chemioally cleansed ; taken from the acid bath they aro woll washed in running wator, and keptia clean water untal tho tinman is ready for them. The tinman takes tho plates from the waterbath (whero they lie some hours) and plunges them wet into a hath of hot palm oil, called the "grease-pot.”” When they have acquired the temperature of the grease-pot, they are removed with tongs and quickly submerged in a bath of tin. The oil mixed with the water from the plates floats at the top, forming a fiux which covors the melted tiu and prevents oxidation. With the tongs, the sheets or plates are continually kept moving and separated, to insure the tia gettlng between all of the sheets. When the bath has recovered its heat, which it genorally does in about half ant hoar, the tinman examines the charge, and ifhe finds that perfect amalgamation hae taken plsce hetween the two metals, he removes them witha tongs to the next hath, whichis kept at a low ‘temperature. The temperatnre raised by the change from the “tin-pot’’is again allowed to cool down to a few degrees over the melting point of the tin, when the platesare taken in lots af a dozen or . . two at a time, and laid an‘an iron slab which is at the side or head of the pot. The waste metal and grease run back into the pot, the slab being inclined, The workman thon takes up sheet by shoet with the tongs, and dips each into anothor hath of fine meta} kept at a heat a little over melting point, immediately withdraws it, and places it in a rack immorsed in a large pot of melted palm oil kept at the proper tempersture, where they are allowed to remsin neertain time. The eheets are then slowly lifted out of the grease by a boy, who separates them into proper lote by counting carefully, regulating the intervals of time hetween them. The grease recoils from the top plate, and, as Tittle is left on the sheets, they are again placed in a rack in the open air to 0001; when cool a lad takes each sheet iu a tongs, and dips the lower edge into 2 small bath of melted tin so regulated that the sheet can only enter to about the eighth of aniuch. Itis kept long enough to ari off the drops of metal which adhere to the lower edge, and when lifted the sheet is struck to throw off the superfinous metal from the edge. The plates are again putinto a rack, and taken while warm toa hin of bran, where each sheet is thrust into aud under the bran, to get rid’of the grease which adheres. It is’ then passed oa to a second and third hana, when the greaseis pretty well behind in the last bin, which is kept filled with new bran, The sheets are turned out covered with flour dust and bran, and dusted off with cotton shaggy cloth. The next process is in the sorting room. Here the finished sheets are laid on tables, and each sheet undergoes an examination by the sorter, who throwa ont those shearings which are defeotive in the iron or trimminge. The latter are reheated to regain the tin; the imperfeot sheets are sold as ‘*wasters” ata less price; the sheets are counted, and the box of 100 Ib.weight is composed of 225 sheote of 14inohes by 10 inohes, for home nse or exportation. New Barrisa Steet Gons.—For some speoinl purposes a very light arm is required, as, for instance, where field-gnns have to be carried over mountainons country, as also for arming the steam launches and pinuaces cartied by iron-clads, and it is to supply this want that the steel weapons have been designed. They weigh but two hundred pounds each, and can, therefore, he carried on a mule,.or in the pra of a boat, without incouvenience. Being ored and fashioned from a single block of steel, the utmost strength, has heen obtained, the weapons being, moreover, tempered in oil to harden them as mach as poasible, after attaining to the proper caliber. The.hore of the gun is thirty-six inches long, and the diameter of the projectile that it firee is four inches. ‘The utmost range of the new arms is etated to be four thousand yards, Up to n recent date, the Westinghouse brake has been under the exclueiye coutrol of the engineer, now it can be applied to the entire train by any person in any car; while the train, in case of derailment, also appliee the. brake to itself, adding an immense impeding force to the obstacles which it otherwise encountere. = In Maine, the building of three masted echoonere is increasing. These yeesele are, on the Atlantic coast, fast superseding other kinds of vessels, They are built cheaper, consequéntly. thére is more profitin their oonetruction, *’ ‘showed great power in grappling with a diffiTransmission of Power by Wire Ropes. At a meeting of the Institution of Mochasical Engineers, London, Mr. Morrisou descrihed the mode of transmission iatrodaced hy the Bros. Hirn, aud now extensivoly ased on the Upper Rhine, It appeared that they first nsed flat metallic hands to transmit the power; but, these heing found ohjectInuablo, ronnd wiro rope was sabseqaently adopted, instead. The rope is usually made of fiac stoel wiro, as it must he very tough and flexihle, The wire rope, which is about one inch in diameter, aud cantains 72 strsnds, is rou st a high velocity, over pulloys of large diameter. The total loss of power by friction, ote., was stated to be 2% per ovnt., and it appeared that, of 120 horee power existing at the motor wheel, 100 horse power was ntilized at 2,200 yards distance; but it could not he elicited in the discussion how these figures had been arrived at. It was alao estlmated that iron shafting, capable of transmitting the same power, woald invulve the use of 3,000 tons of material. Various materials were tried for facing the grooves of the pulleys, éuch as copper, leather, eto., as there either was excessive wear in the groove, or the facing destroyed the rope. The best arrangement was found to be a dovetail groove, filled in with gutta-percha, in which the rope soon made a channel for itself, after which the wear was not excessive. The pulleys run at the rate of 50 miles per hour, and the ropes last from one and a-half to two years. Dr. Siemens remarked that there was no doubt that, by running ropes from 30 to 60 molles per hour over palleys, a large amount of power could be tranemitted with but little waste, Mr. Wm, Smith said that in 1837, soon after his father had invented wire rope, it was used very similarly, and in 1839 and 1840 it was introduced on the Regent’s canal, for towing barges through the tnnnel beneath the Herrow road, and it was also taken three and a-half or four miles along the bank of the canal, The bargeman simply threw a catch line over the Tunning wire, and let go when necessary. It was toeted against the screw, duck-foot propeller and others, but was not found to be economic. He had many times seen a similar application of the principle; the fiy-rope of an ordinary’ ropery wes an illustration, but that had long eince been obsolete. He would like to know whether the paper claimed, as. a . novelty, the introduction of endless wire ropes for transmitting power to a distance; if so, he doubted whether the olaim could be substantiated. If the novelty merely consisted in the runaing of the ropes at a high velocity, which was all he could see in it, there might he something in the claim. * Castino Igon rn SAND Mntps,—In Fairbairn’s Tron Manufacturer we find the following account of the first sucoessful attempt in England to run cast-iron in molds of sand: In 1706, John Darby, one of the four partners of the brass worke known as Beptist Mills, at Bristol, England, conceived the idea that cast-iron might be substituted for brass, and prevailed upon some of the workmen to try and mske iron castings in molds; but they failed, and considerable loss was incurred in théir experimeut. A young Welsh apprentice, who had been a shepherd-boy,’camo into the employ of the Darbys. As he was looking. on during the trial of the Dutch workmen to cast iron, he said to Abraham Darhy that he thought he saw how they had missed it. He begged to be allowed to try, nnd he and Abraham Darhy remained alone in the workshop, the’ same night for the purpose, Before morning they had cast an iron pot. The boy Thomas entered into 6n agreement to serve Ahraham Darby and keep the secret. For more than 100 yeargafter. the night in which Thomas and his master. made their suocessful experiment of producingan iron casting in a mold of fine saud, with its two wooden frames and ‘its air holes, the same process was practiced and kept secret at Colebrook Dale, with plugged key holee and barred‘ doore. % ' &@ paper On coal-cutting machines, read at; Bradford, hy Mr. Firth, mention was made of the extraordinary power of these machines in dispensiug with hand labor, One man, a youth, a boy and a machine, oan compaasa the' work of twelve men, thue reducing ‘‘that hard physical ‘labor ’' by seventy-five per cent. Mnureover, the machine in nse at Ardsley cult seam, aud reduoed the cost of production by Is. 7d. perton. The rapid introduction of coal-cutters seems to promise a revolution in the coal trade, and will doubtless present’an additional indncement to the many capitalists whn are now devoting their energy and their cash to the opening-up of new pits.—English Exchange. ef ok Tue smallest eteam engine on record was made hy a Scotchman, nnmed Crawford. It is, perfect in every part and so small that it can be covered by a lady’s thimble. It can be worked by steam, but he nsually works it by atmospherio pressure, through a flexible tuhe, with rubher airreceiver. The pet éngine was made a8 4n amusement, and to ehow what could he done. It is undoubtedly the emallest working

maohine ever made. _Sroprrno Borrnre.—A new invention consiste in attaching india-rubber tubing to the neck of the bottle, said tube being bent over and se. being oarried off.;. The movement of a glacier Coat-currino Maontnes.—In the course of . ° ‘fluids, and that a body ie electrified positively lor Negatively, ‘according #8 one or the other of ‘these'is in ‘excesy. According to Dr, Frankoured in that position to close the neok of the bottle, e yy ACIENTIFIC (Procress. » Remarkable Motive Power. A curioas capillary experiment was devised by M. Lippmann some months since, which the author has recently utilizedin a very ingenious way, The original experiment is thus deserihed: Place in a saucer orina large wateh-glsss a glohtile of mercury and inch or two in diame. ter, and pour upon it a little water acidalated with sulphuric acid and slightly oolored with potassium hichromate. If now the mercury he touched laterally with the point of a needle, the globule will bo observed to contract and withdraw itself from the needle, then to extend again to its primitive position. This brings it again into contact with the needle, the oontraetion is renewed, aud so on indefinitely, When the globule is qaite large it executes oontorted and grotesque movements which are surprising to those who aro not in the scoret. The explanation of this phenomenon is found in the fact that under the joint inflaence of the iron and the hichromate, the mercury is sucoessively oxidized and deoxidlzed, thereby producing an alteration in its oapillary condition and causing the swelling aud flattening, Thie oxidation and deoxidation may also he effected ‘by an electrio current. The globule is seen to swell up or to flatten, according as it is connected with the negative and deoxidizing or with the positive and oxidizing electrode. It is: this oscillating motion of the globule of mercury that M. Lippmann has utilized ia his: motor. It is constructed as follows: In a trough of glass two small oups are placed, full of mercary; in each of these moves a pistou formed of s bundle of glass tabes. The trongh is filled with acidulated water, and the two masses of meroury are in communication with the electrodes of a battery in such a way that when the one contraots the other flattens, Consequently, when one of the pistons rises the other falls; and hy simply transforming this reciprocating motion of the pistons intn a rotary one, an electro-capillary engine of some hnndredthe of a kilogram-metre of poweris readily obtained. Inthe maohine actaally constructed by M. Lippmann the fiywheel made a hundred revolutions per minute. The extremely feehle current needed to set thie engine in action suggests its mse ae an indicstor of currents too teeble'to be detected by ordinary instruments. Used in this way it would constitute an extremely sensitive electrometer. Indeed it might come in use for the ‘reception of cahle dispatches, which, as is well known, are sent by meaus of very feeble currents, Certain movements of the maohine might correspond to certain predetermined characters or eentences, and in; this way the dispatch might he easily deciphered. Though sourcely more than curious at present, theer exAtmospheric Dust. Among the conclastoue reached by Mr. Cunningham, of Caloutta, in an elaborate series of microscopical examinations of atmospheric dust, are the folowing: ireemeei Specimens of dast washed from exposed stirfaces cannot be regsrded as fair indices of the constituents of atmospherio dust, since they are liable to contain Bodies whioh may have reached the surfsoe otherwise thsn by means of the air, as well ae others which are the result of local development. Specimens collected by gravitation also fail to indicate the nature and amoant of organio cells contained in the atmosphere, as ths heayler amorphous and inorganio constituents of the dust are deposited in relative exoese due to the method of collection. Dew also tails to afford a good meane af inveatigating tho sabject, as it is impossible to secnre that sll the hodies really present in a specimen of it should he collected in a sufficiently small space, and, moreover, becaues it is liable to accldental oontaminatione, and also affords 2 medium in which rapid growth and development are likely to take place. Spores snd other vegetable oells are constantly present in atmospherio dust, and usually oconr 1n considerable numbers; the majority of them are capshle of growth snd development; the amount of them ‘present in the air appeare to he independent of conditions of velocity and direction of wind; and their numbera are not diminished by moisture. The amount of inorganio and amorphous particles and other debris euspended in the atmosphere is direotly dependent on conditions of Moistare and of velocity of wind. New Expuostve.—An English inventor has taken out a pateat for improvements in explosive compounds, in which he usee sawdust, Spent tan, etc., freed from impurities, and submerged for a few moments ia nitrio or sulphuric scid, and mixed with certain nitrates. ‘The tan, ete., when prepared, is termed the wet incipient componnd, and to form explosive compound No. 1, 40 lb. of this is mixed with 60 Ih. Of nitrate of baryta, ammonia, lead or stroutium. To thie mixture ia added 6 lb. of nitro-glacerine, ahsorhed by fine dry eand or infusorial earth, 20 1b, of soft wood charcoal or coal, 10 lb. of chlorate of potash, and 5 lb. of sulphur. The whole is then dried at a temperature of about 90 deg. to 100 deg. Fah. For compound No. 2, 57 lb. of spent tan are mixed with a hoiling saturated solution of nitrate of baryts, soda, eto., 15 lh. -of sulphur,.and 6 Ib. of chlorate of potash, and dried-at about 212 deg. Fah. Compound No. 3 contains 70 lbs of nitrate of baryta, 12 Ib. of anthraoite, sea-coal or soft wood charcoal, 7 lb. af nitrateof potash, 6 lh. of loaf sugsr, 6 lb. of sulphur and 2 Ib. of chlorate of potash, first crunched and then mixed together. The mixture is then damped periments of M. Lippmann are exceedingly in-. With ordinary glyoerine, sufficient to niake its teresting, and will undoubtedly in the future) Various parts cohero, and dried at about 212 receive Important applioations.—Journal of Frantlin Inst. : Cray Guactens.—The gliding masses of clay, resembling glaciete in many: respects, which are to be seen in the velloys Of the Apennines, form the suhject of a memoir communicated to the French Geological Society by’-M. de Mortillet. These mountains oonsist of sandstone, sand and olay. The clays retain water like a sponge, and hedoming saturated, take the form of a sort of slippery dough. Then they slide and move hke glaciers; the pressure on the olay as it glides along the sides of the yalley; causes the calcareous debris to rise-to the surface, which gives the moving ‘mass a further resemblatice to a glacier. iatéral’ moraines, too, are formed, and along the sides of the vslley is fonnd a great accumulation of oalcareous fragmente. ~The pressure~exerted hy these masses is enormous. M. de Mortillet mentions railway embankinents of solid construction being swept away by them, the gravelly stratum on which the émhankments wereoonstracted is due solely to the pressure of the higher portons of it upon the lower, and its’ progress is in proportion to the weight of the mass abové.Glaciers are plastio, it is true, but they can not be eaidto flow. .; i : oe Nature or Execrsicrry. — Attempts haye beeu'made to combine the wave théory of light and electricity by supposing that the vibrations of the ether which produce the phenomena of ‘electricity are longitudinal, reeembliug: those of sonnd, while’the phenomena of light Are produced : hy transverse vibrations of the same medium. Another theory which has'been long believed, is that’ eleotriclty consists of two lin’s theory, there is a'single fiuid and ‘the phenomena depend upon the’ excess or’ deficiency of this fluid. Ahout three yeare' ago, Professor Edlung read 2 paper béfore the Swedish Academy, in which he advanced the theory thst this single fluid was the ether’ by:whose vibratione light is produced; a‘ body heing charged positively when it cantains an ‘excess of ether, and negatively when the ether ie defi‘cient. 7, wi Svoar Contarnep In Vine Leaves,—Petit, the author,’ finds that grape leaves contain from 20 to 30 grme. of glucose per kilogramme, and from 13 tn 16 grms, of acid; of which’ one‘. tation, eg. Fah, Gas Pressors AuarM.—When two neigh. boring buildings are illumiusted by gas @srived -from the same source, it frequently happens ‘that the extinction of the lights in one building causes the pressure of gas in-the other-to become greatly increased, and sometimes to re-ault in accident.. M. Launay -proposes, -as an .2lsrm to give warning of this over-preseure, a -bisulphate of mercury battery, in whioh the Nquid is in communication with the gas by . means of 8 siphon, eo that the pressure of the pas in varying, rsises or lowers ite level. If its pressure is above a certain fixed limit, the liquid is raised so as to come in contact with the metallio portion of the battery, establishi a current which eounds an electrio alarm. : Lsunay also suggests that a simple method of determining leaks in gas pipes throughout a building is to force some strongly .odorous smoke into the supply pipe. The fumes of Inoense, for example, escaping in any room, would be readily distinguished from gas, and the locality of the leak quickly foand. +. Cutnese Mrrzors. — The curious property posseseed hy Chineso metal mirrors of reflecting figures put upon the hack by way of ornamenas long heen a matter of wonder to persons igaorant of the reasons for the phenomenon. Their manufacture is described as follows: Chinese mirrors are castings of a somewhat porous alloy, Before the reflecting face is finally polished, itis laid on an anvil, and the embossed designe or figures at the baok well hammered. This, of coarse, condenses and closes the pores of the metal in these parts, and, in consequence, when the face is finally polished, the metal in front of the design has its power of reflecting light inoreased, and so gives rise to the fallacious idea that the pattern shines through the metal. VasELINE.—The new product of petroleum to which this name has been given promiees to come into use as a vehicle for various emollient preparations, for which it appéare to possees some peculiar advantages. It iea-eolid, semitransparent jelly, neutral, and free from taste or odor, and it is eaid to undergo no change by keeping. It hecomea liquid at a temperature of 95° Fshr. The manufacturers state that it is prepared simply by the evapcration of crude petroleum, and filteriag the residue-through ahimal nharcoal. oy .M. Bertuenor has recently succeeded in third ie tartario acid, mosily existing ag bitartrate of potash. Grape leavee contain eate. sugar as well as glucose, producing nitrite of an:monia for the first time in a oryetalline etate.