Volume 29 (1874) (428 pages)

i . September 26, 1874. MINING AND SCIENTIFIC PRESS. 195 eg BCIENTIFIC Procress. Science Reads an Oracle Relating to the Metallurgy of the Future. One of the most interesting incidents nf the vinit of the American Sociely of Civil Engimeers to the Stevens Institute of Tech. nology, at Hoboken, anggested the above title for our article, After witnessing the beautifal experiments exhibited hy Professor Morton, inspecting the multitnde nf interesting objects in the lecturs room in the Dspariment of Engineering, and spending a pleasant quarter of an hour with Dr Mayer among the mya‘erions physical apperatns of his laboratory, the party orowded Into the littls lecture room of Professor Leeds. The Professur had thrown npon the screen the images of severnl contorted and rather nninteresting looking specimens of mineral, ‘These, he atales, were pisees of ‘* tulgurite,’ or thunderbolt, az it is uften called, aent him from North Carolina, When a heavy finsh ot lightning strikes the earth, it sometimes fuses tho soil in ita track, and, on solidifleation, it becomes a solid har or rod, which may be, and often is, dug ont of its bed. In this case, the lightning had penetrated a bed of pure white aand, melting the silex and forming a hollow shaft two or three inches in diameter and four feet long, filed within and surronnded without by the white sand of the locality. The shaft, however, was not white. Its color varied from a dark to a white pearly gray, Chemical analysis showed it to contain iron, and so accurate was the work that, on estimating it ns ngual, as oxide, ths figures proved some error to have occurred. Estimating it as metallic iron, the figures were correct. Apparently, therefore, the fulgurite was discolored by finely divided motallic iron, and this deduction was contirmed by other and direot oxperiment. This would explain the peonliarity of color, since the oxide woald have colored the silex green. But metallic iron does not exist in natore on the esrth’s snrtace, and the chemist was compelled to seek some explanation of its existence here by an examination of the pecuhar conditions under which it was produced. The final conclusiou aeemed necessarily to be that, at the immensely high temperatnre nt which silica melts(the extreme limi attainable with the oxyhydrogen hlowjpips), iron ‘‘dissociates” from oxygen, and that here, dissociation having ocenrred, the metallio iron, transport ed by the eleotrio flash from some snbterranean deposits, become sncased in molten sand, end was preserved unoxidized within the fulgnrite. The melting of that immensely refractory material, silex, the dissociation of iron from oxygen, and the transportation of such an amount hy electrical action, were circumstances at once remarkable and interesting. Professor Leedg then gave his fellow membera of the society and ot hie profession an ontline or the possible hearing of this onrious instance of natural metallurgy npon the futnre of the art. He stated that, whils it conld hardly yet be considered as robable, it csrtainly did not nppear impossiEi that at some future time the procsssea ot art might imitate what was here seen accomplished by nature, and that this interesting phenomenon might be a strong intimation ot the dirsction in which metallurgical changes might lead. Conld a material be obtained of which to build a furnace which should be capable of resisting the temperatnre at which silex melts, and could such a temperature be attained in the furnace, we need but throw our ore upon the bed of the furnsoe and allow it to reach the temperature of disscciation, when the oxygen would pass off up the chimney, without the nse ot carbon or other deoxidizing agent, and the metal would flow down upon the hearth, ‘The requirement of a nsw retractory material may not improhably bs fulfilled. Equally remarkable discoveries are frequently made. The attainment of so high a temperatnre nscessltates probably the invention of a method of preventing the dissociation of oxygen and bydrogen by high tsmperature. As we also have stated, in an editorial article in our last issne, the limit of combination ot these gascs, or their temperainre nf dissociation, is stated by Deville at about 4,500 degs, Fah., and this is, therefore, the limit ot temperature attainable by their combustion. Oxygen and carhon dissociate at a lower temperatare. The speaker relerred to the possibility that this elevation of the limit may be attainable hy carrying on combustion nuder presaure, as already proposed by Bessomer, and as probably illnstrated in some slight degree by the elevation ot }ressnre within the converter, and the -extraordinary temperatnrea there observed, This interesting aubject andthe novel ideas auggeated by it were evidently looked upon as important aa well as entertaining hy visitors, one of whom expressed the idea which is embodied in the title which we have assumed for our article, and nearly all of whom forgot professional dignity so far as to applaud heartily, “Many of our readers, by the character of their pursnits, are also interested in this anhject. We hope that aome may be so fortunate as to be able to aid in securing the benefit here indicated as possibly attainable.—Scientifie Am. One of the oldest experiments made on a large soale to ascertain the amonnt of heat prodneed by the~ frictional resistance of a certain given power, way made by Benjamin Thompson, of Ooncord, N. H., known in Europe as Count Rumford. Srvevz ayn Carap Grass Certs. — Mr. F. Clowes, of Queenweod college, Hants, sends to ature the follow deacription of a method for extemporizing glass cells with, parallel sides: A piece of India rubber tnbing (or solid rnbber) bent into a semi-circular form is placed between equal sized rectangular plates of gluss, the ends ot the tube terminating at the upper edges of the glass plates; the plates are then held together by passing two strong India rub. herrings over their ends, If the rings are of such 8 size to exert the requisite compression, 4 somi-cirenlar water-tight coll is thns ohtained, which can he taken to pieces and cleansed with Sreatenee. A trough so made served well to exhibit with an ordinary magic lantern the experitpent3 described in Tyndall's ‘Heat a Mode of Motion,’ and smaller oells suitably fitted wilh platiuum wires, and held in the woodeu frame nof an ordinary lantern slide, enabled the galvanic decomposition of aoidulated water and of ssline sulntions to he thrown upon a screen and thus rendered visible to a large andience.” Impaoven Mersop or Gexeratixo CHLorine. l¢ has long been known that ata high temperataro a mixture of chlorhydric acid and air is converted into water and chloriue. Deacon of Englond thns applies this trnusformation, Oblorhydric acid gas at a temperature of from 370 to 400° C. is passed into a vessel containing pisces of porons clay which have been soaked in a solation of sulphate of copper and then baked. The oxide of copper in the pores is converted into the chloride of copper while water is formed. This chloride, when the baked clay contaiuing it is subjected to a current of hot air, is transformed into oxide; the evolvéd chlorine passed through water to absorb any H Cl which had escaped decom position, and then dried, is passed into the cham. bers where the chloride ot lime is manufactured, Meanwhile the oxide of copper is made into chloride ready to evolve Ol again.— Polytechnic Bulletin. 7 CerTaIN improvements in the methods of and materials for decarburating cast iron and converting iron into steel, originate with Mr. C. Binks, chemist and metallurgist, Westminster. In the manufacture of aniline a residual product is obtained, consisting chiefly of precipitsted magnetic oxide of iron with some organic matters containing carbon and nitrogen; and this compound is proposed to bo used for the decarburation of oast iron, in the production of malleable iron, either alone or in combination with the carbonate of soda or of potash; as also for the treatmsnt of cast iron in its conversion into steel, and for adjust. ing the relstive proportions of the iron and azotized carbon iu relation to the constitnent elements of steel. THE use of infusorial earth as a nou-oondnetor of heat is suggested by the Monetary and Mining Gazette. Tripolite or infusorial earth, heing a worse condactor of heat tban coal ashes, and almost as poor as flax chaff, and being refractory, is adapted for walls of ice-cellars and fire-proof safes, for casing steam boilers and pipes, etc., and posscsses the advantage of affording protection against rats and mice. Its lightness is also a great recommendation. One cubic foot of it weighs 21% to 26 pounds; the same bulk of dry coal ashes 40% to 4Qy, pounds, aud of dry earth 94 to 128 pounds. For casing ateam pipes it is mixed with dry flux seed. Aln. Proctor thinks there are several reasons for believing that ths planet Jupiter is not inhabited. The first is its distance from the sun, which so greatly diminishes the amount of heat received thst our lecturer believes it to be inefficient to snstain !ife of auy kind, Another reason is, that the apparent changes in color of the planet’s surface, ascribed by all astronomers to the changes in the clond-masses in its atmosphere, are so great and sudden that Mr. Proctor thinks the heat of the sunis an inadequate canse for them, and that the planet itself must bein a heated state approaching incandescence, Meratiio Attoys.—Mr, H. Hann, of London, has patented (for J. A. Jacoby, of Ham bnrg) an invention which has for its object improvements in the composition of metallio alloys applicable to varions other usetul purposes, such as reducing friction in bearings and other parts of machinery, resisting oxidation, being also oomparatively cheap and economical. Metallic alloys made according to this iuvention consist of from 70 to 73 per cent. of copper, from 9 to Il per cent. of tin, from 15 to 20 per cent. of lead, and from 6.05 to 1 per cent. of zinc. A Genwan chemist has discoyered a procesa by means of which paper may be rendered impervions to moiatnre. He statea that it is sufficient to immerse the paperin an ammoniacal solution ot copper; when the paper is completely dried, it will, with diffienlty, lose its consistence, even in boiling water. The ammoniacal aolntion which ,he employs is Schweetzer’s liqnor, obtained by treating platea of pure copper with a concentrated soln‘tion (88 per cent.) of aal ammoniae while exposed to the atmoaphere, Recenr experiments by M. Sorel prove that carbou retains its refleciing capacity even at the highest temperatures. A snnbeam becomes reflected by diffnsion and is polarized in exactly the same manner, whether it falls upon a brilliant flame or upon earth. M ECHANICAL. ‘Frocress The Sand Blast Again. In a paper read before the British Association, Mr. Newton said; When effects on patterna of a delicate nature are desired, and only small quantities of material are to he removed, the blast of air from an ordinary rotary fan is nsed as the propelling mediam. Sand driven by an air blist of the pressure of four inches of water, will completely grind or de-polish the surface of glass in ten seconds. Ifthe glass is covered by a atencil of paper or lace, or by a design drawn ip any tongh elastic substance, such as balf-deied oil, paint or gnm, a picture will be engraved ou the surtace. Photographie copies in bi-chromated gelatine, from delicate engiavings, have been thns faithfully reproduced on glass. In photographic piciures in gelatine taken from nature, the lights and shadows produce films of gelatine ot different degrees ot thickness. A carefully regnlated sand-blast will act upon the glass beneath these films more or less powerfully in proportion to the thiokness of these filma, and the half-tones or gradations of light and shade are thus prodaced on the glass. It the sand-blast he applied toa cake of resin on which a picture has Bien prodneed by photography in gelatine, or drawn by hand in oil or gam, the bare parts of the surtace May he cut away to any desired depth. The lines left in relicf will be well supported, their hase heing broader than their top, and there being no nnder-cutting, as is apt to occur in etching on metal with acid, an electrotype from this matrix may be made and can be printed from in an ordinary press, The procese had also besn used for cleaning the exterior of bnildings, andit was intended some fine day to polish np St. Panl’s and Westminister Ahhey. ‘his could bs done very rapidly and without injuring the sharp lines or edges of the masonry. A nnmber of bsautifnl and cnrious specimens of glass, marble, slate, granite, ete., operated on by the prooess, were exhibited during the reading of the paper, and excited the most intense interest. Among these was a plate of glass abont half an inch thiok, which had been pierced through in about ten minntes, and also a large flat file, in whicha slit about four inches long and three-eigh ths of an inch broad had been cut by the sand-hlast. Mr. Newton stated, that small shot or grains of cast iron, of about one twenty-sixth ot an inch diameter, in place of the sand, have been found to cnt granite more rapidly; prohably because they are not hroken by the shock, and the whole,force of the blow is thus expended in disintegrating the stone, instead of heing partly wasted in ornabing the grains of sand. The following suggestive paragraph on the same subject we take from a prospectus of a company projected to work the invention: Although the sand-blast has not yet been practically applied to quarrying for slite, either for slabs or roofing slates, it is very confidently believed (from experiments that have recsnily been made) that the invention may be very advantageously applied fer those purposes; and not only will there be a great saving in labor, bnt a large proportion of the blasting reqnired to get the slate ont of the quarry may be dispensed with, and a great deal of the waste material which now takes place may be avoided. As this waste frequently amounts in weight to as much as nine times the weight of the marketable article produced, it will be seen that there is a wide margin for the profitable use of the invention, and for preventing waste. The process is also applicable to qnarryiug stone and for cutting hard rocks in tnnneling in the construction ot railways. It is helieved that in tunneling operations, in many kinds of rocks, a large proportion of the blasting now required may be dispensed with by making nse of the sand blast. A new electric whistle for locomotives is nov coming into use in France. It is intended to take the place of switch signals; opsning the switoh causes a copper plate a short distance offin the roadway to hecome eleetrified. A metallic brush on the engine transfers the cnrreut to the whistle, which is opened, and remains open until the steam is shnt off by the engineer. If the enginesr is neglecting his dnty, the fact is at once made known by the continuous sonnd ot the whistle, A Frenou journal connected with tne metal trade gives the following cniioua estimate of the value of a piece ot iron costing in its rough atate 1f., atter being employed for different manufactures. Made intoa horaeahoe it is worth 3f.; into agricnltural implements, 4t.; forged into ornaments, 45f.; converted into needlea, 75f.; into ateel bnttons, 900 f.; employed as polished steel for decorative purposes, 2,000f.; and made into shirt studs, 6,0U0f. Psor. Tonner remarka that it is enstomary to attribute greater strength to cold rolled iron than to that which has been rolled hot. Although experiment has shown that snch is the case with new iron, yet this is of little importance in practical use, because it does not last. The, strength of anch iron, saya Prof. Tunner, decreasea gradnally with tims. 'Thia is a question which it would be well*to determine by experiment. Lanterns. In many respects ths principles involved in the old grater lanterns are the same as thoss bow applied to lanterns of tho present day. The fornier, it will be remembered, was simply an old tin can, swung trom the hsnd by the aid of a wire or piece of strong twine, and was perforated with many holes to allow the light contained within the can to reach the onter world. The illumination in this c1se was gencra'ly supplied by a picce of candle. The obJects 10 ba attained in the use of this lantern wero to shicld the lamp or candle from the wind and weather, and allow the light to escape trom its shield. We havo abandoned the tallow candle, and for it havo suhstitnted the kerosene lamp, We have endeavored to supply the place of the perforation of the can 'y ihe nse of glass, ca thus to accomplish the double purpese of protecting the flame and of allowing its rays to pass ont of the shield, We have anbstitnted braas or nickel plate for tin, or have nsed the latter article in a more highly finished state; but, after all, but tew essentlal principles are employed in the construction of the modern lantern that may be called new. Davy's *Miner'a”™ lamp, although very old, is nevertheless a novelty, hecause its nse during the last sixty years has never been superseded and scarcely amended. In this lamp it is gonerally known that the glohe or chimney is either wholly or partly composed of a wirs net work, which may become red hot, but neyertheless constitutes an impassable barrier to the flame within the lantern, and thus may he burned with safety in the midst of combnatihls gas.—Iron Age. Restonarioy or Burnt Sreet.--On the destrnctiou, not long ago by fire, of the house of 8 popular officer of high rank, several swords, valued not only for their workmanship and temper, but for tne circumstances under which the owner had become possessed of them, had been rednced to the condition apparently of twisted pieces of hoop iron. They were sent to Birmingham, and some time afterward returned in a condition "differing but little from what they had been before their fiery ordeal.” Supplementing this statement, Messrs, Wilkinson, the sword mannfacturers in Pall Mall, say that it is often of great importance that the onter scale left by the fire shonld not he removed, nor any attempt at cleaning the sarfacs be made unless by experienced hands. In the case of sword blades especially, they find that the minutest details of embossed ornament can gevorally be: traced over the onter scale of burnt steel, and may be copied and restored unless obliterated hy friction, Inlaid or damascened gold work ou stcol will stand a very high degreo of hent without being destroyed, and the fignre of the genuine Damascus blades, being a part of the structure of the metal, oan i Peetored as long as any of the steel remains. ~-Iron. A NEw CuInese Composrtion.—Dr. Scherzer, an Austrian official at Pekin, has sent to his government some specimens of a Chinese composition called ‘‘Schioicao,’’ which has the property of making wood and other snbstances perfectly water-tight. He says that he has seen in Pekin chests which have been to St. Peterabarg and had come back uninjured, and that the Chinese nse the composition also for covering straw baskets, which are afterward employed for carrying oil long distances. Card board, when covered with the composition, becomes as hard as wood, aud most wooden bnildings in Pekin have a coating of it. It consists of three parts ot blood, deprived of its fibrin, four of lime and a little alum. Hocx'’s Perrorevm Moror,—Iu the imperial printing office at Vienna, three presses of a capacity of 1,200 sheets per hour are driven by a motor invented by Hock, which it is said promises to be very usetul for small industrial es. tablishments. Combustion of petrolenm in the working cylinder, and the heat developed by it, constitute the motive power. The machine is said to be very regnlar in action, to be entirely f:e0 from danger, to require little attention, to Occnpy little space, and to be very economical in rnnning, one and a half pounds of petroleum pe honr heing reckoned for one-hcrse power. ike the gus engine, it is also ready at all times, and it is easily cooled down. 7 Jovgnan Bearines.—Dr, C. Knnzel, the iuventor of phosphorus bronze, expresses the opinion that a good metal for bearings onght uot to be homogeneous, bnt should consist of ‘two alloys of different hardness. The harder of these shonld be a porons mass which forms, to acertain extent, the skeleton of the whole, and its pores: or cella ahould be filled with a softer alloy. After a series of experiments Dr. Kunzel haa taken an English patent for the following alloy:.One-fonrth to two parts phoaphorus, 4 to 15 parta lead, 4 to 15 tin, 8 to 15 parts zinc, and copper up to 100 parts. New Pumprno Arparatoa.—Mesers. John Jonea & Sons, of the Old Buffery Colliery and Fnrnacea, Dudley, England, have lately pnt down a powerfnl pumping apparatna, the engine of which does a vast amouut of work with a minimum of power. It is calleda ’‘bull’’ engine, is of 80 horse power, and was made hy Messrs. Lee, of Patricroft, near Manchester. The cylinder is 30 inches in diameter, with a working barrel of 12 inches to the lift and an eight-foot stroke. Withone boiler 30 feet by five and a half feet, this engine raises 1,250 tons of water per day,

i . September 26, 1874. MINING AND SCIENTIFIC PRESS. 195 eg BCIENTIFIC Procress. Science Reads an Oracle Relating to the Metallurgy of the Future. One of the most interesting incidents nf the vinit of the American Sociely of Civil Engimeers to the Stevens Institute of Tech. nology, at Hoboken, anggested the above title for our article, After witnessing the beautifal experiments exhibited hy Professor Morton, inspecting the multitnde nf interesting objects in the lecturs room in the Dspariment of Engineering, and spending a pleasant quarter of an hour with Dr Mayer among the mya‘erions physical apperatns of his laboratory, the party orowded Into the littls lecture room of Professor Leeds. The Professur had thrown npon the screen the images of severnl contorted and rather nninteresting looking specimens of mineral, ‘These, he atales, were pisees of ‘* tulgurite,’ or thunderbolt, az it is uften called, aent him from North Carolina, When a heavy finsh ot lightning strikes the earth, it sometimes fuses tho soil in ita track, and, on solidifleation, it becomes a solid har or rod, which may be, and often is, dug ont of its bed. In this case, the lightning had penetrated a bed of pure white aand, melting the silex and forming a hollow shaft two or three inches in diameter and four feet long, filed within and surronnded without by the white sand of the locality. The shaft, however, was not white. Its color varied from a dark to a white pearly gray, Chemical analysis showed it to contain iron, and so accurate was the work that, on estimating it ns ngual, as oxide, ths figures proved some error to have occurred. Estimating it as metallic iron, the figures were correct. Apparently, therefore, the fulgurite was discolored by finely divided motallic iron, and this deduction was contirmed by other and direot oxperiment. This would explain the peonliarity of color, since the oxide woald have colored the silex green. But metallic iron does not exist in natore on the esrth’s snrtace, and the chemist was compelled to seek some explanation of its existence here by an examination of the pecuhar conditions under which it was produced. The final conclusiou aeemed necessarily to be that, at the immensely high temperatnre nt which silica melts(the extreme limi attainable with the oxyhydrogen hlowjpips), iron ‘‘dissociates” from oxygen, and that here, dissociation having ocenrred, the metallio iron, transport ed by the eleotrio flash from some snbterranean deposits, become sncased in molten sand, end was preserved unoxidized within the fulgnrite. The melting of that immensely refractory material, silex, the dissociation of iron from oxygen, and the transportation of such an amount hy electrical action, were circumstances at once remarkable and interesting. Professor Leedg then gave his fellow membera of the society and ot hie profession an ontline or the possible hearing of this onrious instance of natural metallurgy npon the futnre of the art. He stated that, whils it conld hardly yet be considered as robable, it csrtainly did not nppear impossiEi that at some future time the procsssea ot art might imitate what was here seen accomplished by nature, and that this interesting phenomenon might be a strong intimation ot the dirsction in which metallurgical changes might lead. Conld a material be obtained of which to build a furnace which should be capable of resisting the temperatnre at which silex melts, and could such a temperature be attained in the furnace, we need but throw our ore upon the bed of the furnsoe and allow it to reach the temperature of disscciation, when the oxygen would pass off up the chimney, without the nse ot carbon or other deoxidizing agent, and the metal would flow down upon the hearth, ‘The requirement of a nsw retractory material may not improhably bs fulfilled. Equally remarkable discoveries are frequently made. The attainment of so high a temperatnre nscessltates probably the invention of a method of preventing the dissociation of oxygen and bydrogen by high tsmperature. As we also have stated, in an editorial article in our last issne, the limit of combination ot these gascs, or their temperainre nf dissociation, is stated by Deville at about 4,500 degs, Fah., and this is, therefore, the limit ot temperature attainable by their combustion. Oxygen and carhon dissociate at a lower temperatare. The speaker relerred to the possibility that this elevation of the limit may be attainable hy carrying on combustion nuder presaure, as already proposed by Bessomer, and as probably illnstrated in some slight degree by the elevation ot }ressnre within the converter, and the -extraordinary temperatnrea there observed, This interesting aubject andthe novel ideas auggeated by it were evidently looked upon as important aa well as entertaining hy visitors, one of whom expressed the idea which is embodied in the title which we have assumed for our article, and nearly all of whom forgot professional dignity so far as to applaud heartily, “Many of our readers, by the character of their pursnits, are also interested in this anhject. We hope that aome may be so fortunate as to be able to aid in securing the benefit here indicated as possibly attainable.—Scientifie Am. One of the oldest experiments made on a large soale to ascertain the amonnt of heat prodneed by the~ frictional resistance of a certain given power, way made by Benjamin Thompson, of Ooncord, N. H., known in Europe as Count Rumford. Srvevz ayn Carap Grass Certs. — Mr. F. Clowes, of Queenweod college, Hants, sends to ature the follow deacription of a method for extemporizing glass cells with, parallel sides: A piece of India rubber tnbing (or solid rnbber) bent into a semi-circular form is placed between equal sized rectangular plates of gluss, the ends ot the tube terminating at the upper edges of the glass plates; the plates are then held together by passing two strong India rub. herrings over their ends, If the rings are of such 8 size to exert the requisite compression, 4 somi-cirenlar water-tight coll is thns ohtained, which can he taken to pieces and cleansed with Sreatenee. A trough so made served well to exhibit with an ordinary magic lantern the experitpent3 described in Tyndall's ‘Heat a Mode of Motion,’ and smaller oells suitably fitted wilh platiuum wires, and held in the woodeu frame nof an ordinary lantern slide, enabled the galvanic decomposition of aoidulated water and of ssline sulntions to he thrown upon a screen and thus rendered visible to a large andience.” Impaoven Mersop or Gexeratixo CHLorine. l¢ has long been known that ata high temperataro a mixture of chlorhydric acid and air is converted into water and chloriue. Deacon of Englond thns applies this trnusformation, Oblorhydric acid gas at a temperature of from 370 to 400° C. is passed into a vessel containing pisces of porons clay which have been soaked in a solation of sulphate of copper and then baked. The oxide of copper in the pores is converted into the chloride of copper while water is formed. This chloride, when the baked clay contaiuing it is subjected to a current of hot air, is transformed into oxide; the evolvéd chlorine passed through water to absorb any H Cl which had escaped decom position, and then dried, is passed into the cham. bers where the chloride ot lime is manufactured, Meanwhile the oxide of copper is made into chloride ready to evolve Ol again.— Polytechnic Bulletin. 7 CerTaIN improvements in the methods of and materials for decarburating cast iron and converting iron into steel, originate with Mr. C. Binks, chemist and metallurgist, Westminster. In the manufacture of aniline a residual product is obtained, consisting chiefly of precipitsted magnetic oxide of iron with some organic matters containing carbon and nitrogen; and this compound is proposed to bo used for the decarburation of oast iron, in the production of malleable iron, either alone or in combination with the carbonate of soda or of potash; as also for the treatmsnt of cast iron in its conversion into steel, and for adjust. ing the relstive proportions of the iron and azotized carbon iu relation to the constitnent elements of steel. THE use of infusorial earth as a nou-oondnetor of heat is suggested by the Monetary and Mining Gazette. Tripolite or infusorial earth, heing a worse condactor of heat tban coal ashes, and almost as poor as flax chaff, and being refractory, is adapted for walls of ice-cellars and fire-proof safes, for casing steam boilers and pipes, etc., and posscsses the advantage of affording protection against rats and mice. Its lightness is also a great recommendation. One cubic foot of it weighs 21% to 26 pounds; the same bulk of dry coal ashes 40% to 4Qy, pounds, aud of dry earth 94 to 128 pounds. For casing ateam pipes it is mixed with dry flux seed. Aln. Proctor thinks there are several reasons for believing that ths planet Jupiter is not inhabited. The first is its distance from the sun, which so greatly diminishes the amount of heat received thst our lecturer believes it to be inefficient to snstain !ife of auy kind, Another reason is, that the apparent changes in color of the planet’s surface, ascribed by all astronomers to the changes in the clond-masses in its atmosphere, are so great and sudden that Mr. Proctor thinks the heat of the sunis an inadequate canse for them, and that the planet itself must bein a heated state approaching incandescence, Meratiio Attoys.—Mr, H. Hann, of London, has patented (for J. A. Jacoby, of Ham bnrg) an invention which has for its object improvements in the composition of metallio alloys applicable to varions other usetul purposes, such as reducing friction in bearings and other parts of machinery, resisting oxidation, being also oomparatively cheap and economical. Metallic alloys made according to this iuvention consist of from 70 to 73 per cent. of copper, from 9 to Il per cent. of tin, from 15 to 20 per cent. of lead, and from 6.05 to 1 per cent. of zinc. A Genwan chemist has discoyered a procesa by means of which paper may be rendered impervions to moiatnre. He statea that it is sufficient to immerse the paperin an ammoniacal solution ot copper; when the paper is completely dried, it will, with diffienlty, lose its consistence, even in boiling water. The ammoniacal aolntion which ,he employs is Schweetzer’s liqnor, obtained by treating platea of pure copper with a concentrated soln‘tion (88 per cent.) of aal ammoniae while exposed to the atmoaphere, Recenr experiments by M. Sorel prove that carbou retains its refleciing capacity even at the highest temperatures. A snnbeam becomes

reflected by diffnsion and is polarized in exactly the same manner, whether it falls upon a brilliant flame or upon earth. M ECHANICAL. ‘Frocress The Sand Blast Again. In a paper read before the British Association, Mr. Newton said; When effects on patterna of a delicate nature are desired, and only small quantities of material are to he removed, the blast of air from an ordinary rotary fan is nsed as the propelling mediam. Sand driven by an air blist of the pressure of four inches of water, will completely grind or de-polish the surface of glass in ten seconds. Ifthe glass is covered by a atencil of paper or lace, or by a design drawn ip any tongh elastic substance, such as balf-deied oil, paint or gnm, a picture will be engraved ou the surtace. Photographie copies in bi-chromated gelatine, from delicate engiavings, have been thns faithfully reproduced on glass. In photographic piciures in gelatine taken from nature, the lights and shadows produce films of gelatine ot different degrees ot thickness. A carefully regnlated sand-blast will act upon the glass beneath these films more or less powerfully in proportion to the thiokness of these filma, and the half-tones or gradations of light and shade are thus prodaced on the glass. It the sand-blast he applied toa cake of resin on which a picture has Bien prodneed by photography in gelatine, or drawn by hand in oil or gam, the bare parts of the surtace May he cut away to any desired depth. The lines left in relicf will be well supported, their hase heing broader than their top, and there being no nnder-cutting, as is apt to occur in etching on metal with acid, an electrotype from this matrix may be made and can be printed from in an ordinary press, The procese had also besn used for cleaning the exterior of bnildings, andit was intended some fine day to polish np St. Panl’s and Westminister Ahhey. ‘his could bs done very rapidly and without injuring the sharp lines or edges of the masonry. A nnmber of bsautifnl and cnrious specimens of glass, marble, slate, granite, ete., operated on by the prooess, were exhibited during the reading of the paper, and excited the most intense interest. Among these was a plate of glass abont half an inch thiok, which had been pierced through in about ten minntes, and also a large flat file, in whicha slit about four inches long and three-eigh ths of an inch broad had been cut by the sand-hlast. Mr. Newton stated, that small shot or grains of cast iron, of about one twenty-sixth ot an inch diameter, in place of the sand, have been found to cnt granite more rapidly; prohably because they are not hroken by the shock, and the whole,force of the blow is thus expended in disintegrating the stone, instead of heing partly wasted in ornabing the grains of sand. The following suggestive paragraph on the same subject we take from a prospectus of a company projected to work the invention: Although the sand-blast has not yet been practically applied to quarrying for slite, either for slabs or roofing slates, it is very confidently believed (from experiments that have recsnily been made) that the invention may be very advantageously applied fer those purposes; and not only will there be a great saving in labor, bnt a large proportion of the blasting reqnired to get the slate ont of the quarry may be dispensed with, and a great deal of the waste material which now takes place may be avoided. As this waste frequently amounts in weight to as much as nine times the weight of the marketable article produced, it will be seen that there is a wide margin for the profitable use of the invention, and for preventing waste. The process is also applicable to qnarryiug stone and for cutting hard rocks in tnnneling in the construction ot railways. It is helieved that in tunneling operations, in many kinds of rocks, a large proportion of the blasting now required may be dispensed with by making nse of the sand blast. A new electric whistle for locomotives is nov coming into use in France. It is intended to take the place of switch signals; opsning the switoh causes a copper plate a short distance offin the roadway to hecome eleetrified. A metallic brush on the engine transfers the cnrreut to the whistle, which is opened, and remains open until the steam is shnt off by the engineer. If the enginesr is neglecting his dnty, the fact is at once made known by the continuous sonnd ot the whistle, A Frenou journal connected with tne metal trade gives the following cniioua estimate of the value of a piece ot iron costing in its rough atate 1f., atter being employed for different manufactures. Made intoa horaeahoe it is worth 3f.; into agricnltural implements, 4t.; forged into ornaments, 45f.; converted into needlea, 75f.; into ateel bnttons, 900 f.; employed as polished steel for decorative purposes, 2,000f.; and made into shirt studs, 6,0U0f. Psor. Tonner remarka that it is enstomary to attribute greater strength to cold rolled iron than to that which has been rolled hot. Although experiment has shown that snch is the case with new iron, yet this is of little importance in practical use, because it does not last. The, strength of anch iron, saya Prof. Tunner, decreasea gradnally with tims. 'Thia is a question which it would be well*to determine by experiment. Lanterns. In many respects ths principles involved in the old grater lanterns are the same as thoss bow applied to lanterns of tho present day. The fornier, it will be remembered, was simply an old tin can, swung trom the hsnd by the aid of a wire or piece of strong twine, and was perforated with many holes to allow the light contained within the can to reach the onter world. The illumination in this c1se was gencra'ly supplied by a picce of candle. The obJects 10 ba attained in the use of this lantern wero to shicld the lamp or candle from the wind and weather, and allow the light to escape trom its shield. We havo abandoned the tallow candle, and for it havo suhstitnted the kerosene lamp, We have endeavored to supply the place of the perforation of the can 'y ihe nse of glass, ca thus to accomplish the double purpese of protecting the flame and of allowing its rays to pass ont of the shield, We have anbstitnted braas or nickel plate for tin, or have nsed the latter article in a more highly finished state; but, after all, but tew essentlal principles are employed in the construction of the modern lantern that may be called new. Davy's *Miner'a”™ lamp, although very old, is nevertheless a novelty, hecause its nse during the last sixty years has never been superseded and scarcely amended. In this lamp it is gonerally known that the glohe or chimney is either wholly or partly composed of a wirs net work, which may become red hot, but neyertheless constitutes an impassable barrier to the flame within the lantern, and thus may he burned with safety in the midst of combnatihls gas.—Iron Age. Restonarioy or Burnt Sreet.--On the destrnctiou, not long ago by fire, of the house of 8 popular officer of high rank, several swords, valued not only for their workmanship and temper, but for tne circumstances under which the owner had become possessed of them, had been rednced to the condition apparently of twisted pieces of hoop iron. They were sent to Birmingham, and some time afterward returned in a condition "differing but little from what they had been before their fiery ordeal.” Supplementing this statement, Messrs, Wilkinson, the sword mannfacturers in Pall Mall, say that it is often of great importance that the onter scale left by the fire shonld not he removed, nor any attempt at cleaning the sarfacs be made unless by experienced hands. In the case of sword blades especially, they find that the minutest details of embossed ornament can gevorally be: traced over the onter scale of burnt steel, and may be copied and restored unless obliterated hy friction, Inlaid or damascened gold work ou stcol will stand a very high degreo of hent without being destroyed, and the fignre of the genuine Damascus blades, being a part of the structure of the metal, oan i Peetored as long as any of the steel remains. ~-Iron. A NEw CuInese Composrtion.—Dr. Scherzer, an Austrian official at Pekin, has sent to his government some specimens of a Chinese composition called ‘‘Schioicao,’’ which has the property of making wood and other snbstances perfectly water-tight. He says that he has seen in Pekin chests which have been to St. Peterabarg and had come back uninjured, and that the Chinese nse the composition also for covering straw baskets, which are afterward employed for carrying oil long distances. Card board, when covered with the composition, becomes as hard as wood, aud most wooden bnildings in Pekin have a coating of it. It consists of three parts ot blood, deprived of its fibrin, four of lime and a little alum. Hocx'’s Perrorevm Moror,—Iu the imperial printing office at Vienna, three presses of a capacity of 1,200 sheets per hour are driven by a motor invented by Hock, which it is said promises to be very usetul for small industrial es. tablishments. Combustion of petrolenm in the working cylinder, and the heat developed by it, constitute the motive power. The machine is said to be very regnlar in action, to be entirely f:e0 from danger, to require little attention, to Occnpy little space, and to be very economical in rnnning, one and a half pounds of petroleum pe honr heing reckoned for one-hcrse power. ike the gus engine, it is also ready at all times, and it is easily cooled down. 7 Jovgnan Bearines.—Dr, C. Knnzel, the iuventor of phosphorus bronze, expresses the opinion that a good metal for bearings onght uot to be homogeneous, bnt should consist of ‘two alloys of different hardness. The harder of these shonld be a porons mass which forms, to acertain extent, the skeleton of the whole, and its pores: or cella ahould be filled with a softer alloy. After a series of experiments Dr. Kunzel haa taken an English patent for the following alloy:.One-fonrth to two parts phoaphorus, 4 to 15 parta lead, 4 to 15 tin, 8 to 15 parts zinc, and copper up to 100 parts. New Pumprno Arparatoa.—Mesers. John Jonea & Sons, of the Old Buffery Colliery and Fnrnacea, Dudley, England, have lately pnt down a powerfnl pumping apparatna, the engine of which does a vast amouut of work with a minimum of power. It is calleda ’‘bull’’ engine, is of 80 horse power, and was made hy Messrs. Lee, of Patricroft, near Manchester. The cylinder is 30 inches in diameter, with a working barrel of 12 inches to the lift and an eight-foot stroke. Withone boiler 30 feet by five and a half feet, this engine raises 1,250 tons of water per day,