Volume 24 (1872) (424 pages)

June 15, 1872.] SCIENTIFIC . BRESS. §oientiric Proaress. A Waning Star. In our last issuo we made refersnec to the disappearanco of the star, Eta Leonis [the printer made us say Mu Leouis]. Sinco that peragraph appeared we have seen a note from Geo, Madeira, of Santa Cruz, who, having examined this star with, probahly, a more powerful telescope thau tho San Francisco observer, reports that on the Ist iustant it waa fast diminishing in brilliancy hut had vot at that timo disappeared entirely. Mr. M. promises to continue his observatious for a few weeks and give the public an accouut of the same. Such phenemena as tho disappearance of a star or any variation in a star ick has hitherto waintained a permanent degree of luminosity, are of very rare occurrence and perhaps, a short reference to the more uoted phenomena of this kind which have heretoforo been uoticed may ho appropriate in connection with the one which is now attracting the atteution of astronomers. During tho last 2,000 years there have been noticed some 20 ‘‘tomporary stars,” which havo auddenly made their appcarance in the hea veus only to hlaze out or tlicker awhile and finally to disappear entirely. Of the variuble stars, which iucrease and dimiinish their light periodically, only ahout 24 have boen thus far recorded. The first variablo star, Mira in the constellation, Celus, was uoticed in 1596. Snbsequent observations have shown that this star hasa periodicity of about 332 days, during which time it increases from total obscurity to a star of the secoud magnitude. Wheu decreasing, it changes its color from white to red. Seventy-three years afterwards, the noted star Argol (the demon star) was observed to be variable, It passes through its variations from the 2d to the 4th magnitude, and vice versa, overy sixty-eight hours, Tho star Cephas, makes its changes from 3d to 5th ningnitude, in about 5% days. The most wonderfnl of the temporary stars, was seon in 1572, It appeared suddenly in the constellation, Cassiopea, and very soon renched the brightness of Sirins, after which it increased in brilhancy until it surpassed ovon Jnpiter or Venus, and could even be seen in the day-time. Its period of increase was abont one month; but its period of waning was very gradual—tasting about fifteen months. Thia star was first white, then red and finally white again. Somo astronomers think that this is a variahle star of long period—about 313 years, from the fact that asimilarappearance was observed in the same portion of the heavens in 945 and again in 1264. Its anthentic appearance having been in 1572, if the surmise of its periodicity is correct its next appearance will be in 1885. The most remarkable temporary star of recent times was the one which suddenly blazed out with a brilliancy of the 2d magnitnde, on the 12th of May, 1866, in the constellation of the Corona Borealis. In its place, previously, had been recorded a telescopic star of the 10th magnitude. The sudden appearance of this star created quite an excitement in thescicntific world. It was carefully investigated by Hnggins with the spectroscope, who arrived at the conclusion that the star owed its sudden brightness to the evolution of flaming hydrogen. It was naturally supposed that such an active conflagration of. that matter could not be of long continuance, and that its exccssivo brilliancy would soon fade away; a prediction which was fully verified, as tho hydrogen lines disappeared in tite spectrum in abont eight days. Itrapidly waned to the 6th magnitnde, and more gradually from that to the 10th—its original record. Since 1868 it fluctuates slightly, but singularly, unlike the ordinary variable stars. In 1870 it was of the 7th magnitudc, and now it shines with the 8th. The variations of the pcriodically variable stars are generally thought to be due to the fact that they are double stars, revolving around a common centcr—onc being brighter than the other. In cases of total temporary disnppearauce, one star may be totally devoid of light. Again “sun spots’? may in somo cases account for the phenomena of waxing and waning. Tn that sense the center of our solar system— the sun— is a periodically variable star of elevcn years time—that being the period of its presentation of a greater or less;number of ‘‘sunspots.” With the later improvements and better understanding of the spectroscope, great advance is now being made in astronomical knowledge —particularly in relation to the physical condition of the heavenly hodies. Spectroscopic observations on the star Eta, which jnst now seems to be gradually flickering itself ont of our view, willbe looked for with much interest. Tse CrysTALLization oF Iron AND STEEL.— The various qualities of iron and steel may be compared by observing the forms of their crystals through a microscope. Cast steel of fine quality exhibits fine crystals of a needle-hke shape parallel to each other; and the axes of these crystals are in the direction of the hammering to which the metal has been subjected. The surface of iron exhibits crystals of the shape of a double pyramid, the proportions varying with the quahty of the metal. The pyramids more nearly approach a cubical form as the carbon in the metal is increased in quantity. Measuring the Light of Stars. Zoelner, of Berlin, has recently made an important addition to the means by which tho astronomer sevks to measure the degree of light emitted from a star. The small quantity of light which reaches us froni these distant bodies, renders the look ef measuring the same by the instruments heretofore in nse extremely difticult. The invention of Mr. Z., is a polariscopo connected with a tclescope. i this iustrnment, a ray of light is made to disappear and reappear altetuately, by simply turniug an eyepieco of Iceland spararound Its axis, throngh an augle of 90°, This disappearance and reappearancs is gradual, and the angle of rotation from 0° to 902, may therefore be nssd as & measnre of the intensity of the light—the stronger the light, the greater the rotation reqnired to be toned down toacertain standard. Important results have already been obtained by tho use of this instrument. One of tho most important results of this instrumeut, is the power which it givss of mors accurately determining the periods of the variable stars. Heretofors it has been so difficult to measure the intensity of ths light from a star, it was quite imposaibls to detect with even much approximate accuracy, tho preciss timo oceupied hy a star in passing from ita period of Isast light through its gradual increass and subsequent decrease of light, again to ita point of least brilliancy. Rostnornite, A New Foss. Resiy.—A new fossil resin, named rosthornite, is describsd by Hofer as occuring in the coal of the Sonueberg, in Cariuthin. This has a fatty lustre, a brown color with garnct-red gloss, wins-yellow hy transmitted light, and a light brown to orange yellow strenk. When heated in the air it gives off white vapors having an aromatic odor, and burns with a smoky flame without leaving any residue, In chemical composition this mineral approaches most nearly to enosmite, and atill more to the fossil resin of Girona, in New Grenada. This substance cau not be properly assigned to auy of the groups already established amoug the fossil resins, but scems rather to conform to the type of a solid resin, rich in carhon but poor in oxygen. Tne spectrum of hydrogen has been recent ly made the subject of experiment by Prof. Angstrom ; he states that it prescnts only four lines, and consideres that the other spectra that have been given arein error from the presence of impurities. Ho also examined the spectra of atmospheric air under different degrees of rarefaction, and fouud that at first it was that of air; then of nitrogen; then of carbonic oxide ; and when the exhaustion had reached its utmost limit the spectrum obtaincd was that of sodium and chlorinc. Coativo Metats wire Nicken ny THE Motsr Wax.—According to C. Mene, wrought and cast-iron, steel, copper, brass, zinc, and lead ean be coated with nickol by putting theso metals, or objectsamade of them, ina boiling nentral solution of chloride of zinc, to which a salt of nickel is added, and also zinc, in a grannlated state orin sheets. If the solution be acid the coating will be dnll. When, instead of a salt of nickel,.ono of cobalt be used, a coating of that metal may be obtained. Manrvets or THE Microscorzr.—A beautiful and easily produced exhibition of crystal formation may be seen under the microscope as follows: Upon a slip of glass place a drop of liquid chloride of gold or nitrate of silver, with a particle of zinc in the gold and copper in the silver, A growth of exquisite gold or ailver ferns will vegetate under the observer’s eye. A Sociuty or Ants, Sciences and Letters, has just been started at Winona, Minn., in connection with the first State Normal School in that place, having for its object tho collection of facts and materials looking toward the determination of tho natural history, archmology, and general literature of the United States. Ayorner Sincinc Fuamz.—aAt a late session of the Philosophical Society of Glasgow, held lately, Dr. A. Irvine showed some experiments on a new variety of singing flame, and described and experimented with a new miner’s safety-lamp, which involves the application of that flame. The experiments excited a great amount of interest among the members. Artirican Musx.—Prof. Vander Weyde, at a late meeting of the Polytechnic Association of tho American Institute exhibited an artificial musk, made by treating blood in a peculiar manner. By adding little hairs, such as are found in gennine musks, the’ deception is so complete that it cannot be detected even by the microscope. Waeataer Prepictions.—President Tillman, of the Polytechnic Association of the American Institute, says the weather predictions which are daily published in our newspapers have been verified to about 75 per cent.; that is, three-fourths of all the predictions which they have made have been fonnd te be true. Tue British Socicty for the Advancement of Art still offer the $5,000 reward for a pigment or covering which will perfectly protect iron from rust and fouling. M. Cuampounton avers that pntrifaction is much more rapid in the dead bodiea of those who have used alcohol to excess than in those of comparatively sober individuals, Ni ECHANICAL Proaress Granite Works of the Ancients. The following, from an exceedingly interesting account of the colossal granite structures of aucieut Egypt, India and South America, appearsin the curreut number ef the People’s Magazine — The art of earving in granite has never heen earried to higher perfection than on the continent of India, At Chillambaraiu, also in the Carnatic, and on the Coromandel coast, is a congeries of temples, representing the sacred Monnt of Meru. Here are seven lofty walls, one withiu the other, round ths central quadrangic, and as many pyraiuidal gateways in the midst of each side, which form ths limhs of a vast cross; consisting altogetber of twenty-eight pyramids. hero are consequently feurtceu in a linc, which extend more than a mile iu one coutinueus direction! Nor are these the only wonders associated with this metropolis of pyramids. The interior ornaments are in harmouy with the whols; from the nave of one of the principal structures thsre hang, on the tops of four buttresses, festeons of chains, in length about 548 feet. Each garland, consistiug of twenty links, is made of ono piece of granits, sixty feet long; the links themselves ars monstrona rings, thirty-two inches in cireumferencs, and 4 as smooth as glass. Compared with ths monolith temples of granite at Mahabaiipuram, which is likewise situated on tbo Coromaudel coast, thoso in Egypt sink into insignificance. The rocks thercabouts are composed of a hard gray granite, containing quartz, mica, and feldspar, with a few crystals of hornblende interspersed. Many have been hollowed out by art, and seulptured into temples with spirited bas-reliefs, representing episodes in Hindoo history and mythology, and supported by graceful colnmns; all carved from the solid rock. Detached masses havo been cut into shapes of elephants, tigers, Hons, bulls, cats, monkeya, and yarions nondescript monsters, and colossal statucs of gods, one of which; namely, that of Ganesa, being thirty fcet high. “The southernmost of the temples is abont 40 ft. in hight, 27 ft. in breadth, and nearly the same in length; the exterior being covered with elaborate sculptures. The adjoining edifice is about 49 ft. in length, and in breadth 26 ft.; it is rent by natural causes from summit to base. According to the local Brahminical tradition, these wonderfn] sculptures were executed by 4,000 workmen, who had come from the north, and returned before their completion. From a eareful examination, it is evident that almost all the enormons mass of sculpture and carving that adorns this city of monolith temples and colossi, must have been performed withont the aid of —with the hammer, chisel, lever, and wedge alone; and this is one of the hardest rocks in the world?” A Sxont Coat Supriy.—A correspoudent in Engineering saysthat almost any price can be had for coals in the north of England, by those who are fortunate enough to have any for sale. The demand is so heavy that the additions which are being made to pits, and the new pits which are being sunk, seem to go but a very little way in meeting the extra requirements of consumers. Everybody is crying ont for more fuel, and, do what they will, they cannot get it quick enongh. To meet this extraordinary increasing demand, hand labor is inadequate. Good coal-cutting machines must be forthcoming. The attention of a great many engineers are directed to this qnestion of coal cutting, and, in this age of invention, it will be remarkable if suitable machines are not soon introducod. Unless machines aro applied to coalcutting, there isnot the slightest doubt that the iron trade and other industries will be crippled in their development for want of fnel. Goal being scarcer, there is, of course, the greatest difficulty in obtaining coke. Anturictan LeatHer.—Among the different kinds of artificial leather lately introduced, is tho following:—-J, Charles, in London, and C. Taylor, in Manchester, England, take boiled linseed-oil, and boil it again with quicklime and borax, till they obtain a finid, which, by cooling, nearly solidifiss into a thick dough. To this they add pniverized cork, and some quicklime, and the paste obtained is rolled out into sheets, which, if desired to be very smooth, after being dried, and rubbed down by means of pumice-stone. The process is evidently a partial sponification, and reminds ua of the artificial India rubber, which is also made of linseed-oil, withont the addition of the powdered cork, which serves only to give the ge of leather, and is a mere filling or adulteration of the tenacious chief ingredient, in the same way as India rubber is adulterated by similar fillings. Puppuine Furnaces 1x Grear Briran.— There are about 7,800 pudding furnaces in Great Britain, employing 26,000 men, involying an investment of over $5,000,000. All these furnaces are now worked by hand, or at least with but trifling help from mechanical device. It is expected that a revolution will soon be wrought out with this immense industry, by use of the mechanical puddlers, which have already been proven snecessful in their application. Improvement of the Steam Engine. In a paper read before the Polytechnic Association of the American institute by Professor Thurston, on the ahove subject, he snmmed up his conclnsions iu the following statsments: The direction which improvement seems now to be taking, and the proper direction, ns iudicated by an examination of tbe principles of scieuce, as well as hy our review of the steps already taken, seem to he: Steam must enter the machine at the highest possible temperature, must bo protected from waste, and must retain, at the moment befors exhaust,theleast possibleamountofheat. He whose inventive genius of mechanical skill contributes te effect either ths use of highsr steam with safety and without waste, or the reductiou of the temperature of dischargs, confers a boou upon mankind. Tu detail: In the engine, ths tendency is, and may probably bs expected to coutinue, in ths near future at least, toward higher steem pressure, greater expansion in wore than one eylinder, steam jacketing, superheating, a careful use of non-conducting protectors against waste, and ths adoption of higher piston speeds. In the boiler, more complete combustion withont success of air passing through the furnace and more thorough ahsorption of heat from the furnacs gases. The latter, I am inclined to suppose, will be nitimately effected by the uso of a mechanically produced dranght, in place of the far more wasteful method of obtaining it hy the sxpenditure of heat iu the chimney. ‘ In construction, we may anticipate the nss of better materials and mors careful workmanship especially in the boilsr, and much imPE in forms and proportions of details. In management, there is a wide field for improvement, which improvement we may feel assured will rapidly take place, as it has now become well uuderstood that great care, skill and intelligence are important essentials to the economical management of the steani engine and that they repay liberally all of the expense in time and money that are requisito to aecure them. A New Kip or Frov1t-Grass.—Dr. Benrath, Director of the glassworks at Dorpat, Russia, publishes an account of experiments made by him to produce a glass which has the good qualities of flint-glass without its defects, ‘The good qualities of ordinary flint-glaas are, that it is as clear as crystal; that it has a high specific gravity, (is heavy;) a low fusing point, so that it melts easily; and strong power of refraction and dispersing light. Itis, therefore, invaluable for chemical and optical purposes. Its defects, however, are that it is easilyacted on by chemical and mechanical influences—that means ita surfaco cannot stand rain and sunshine, much less acids or boiling water, and it is so soft that it is most easily scratched. The chemical difference between ordina) and flint-glass is that the former consists of silex, lime, and soda or potash, while oxide of lead is added to make flint-glass out of it. Chemically speaking, common glass is a silicate of lime and potash; while flint-glass contains also silicate of lead. Corrina Marnie.—A recently devised foreign .apparatus for stone-eutting uses comprises.a hoad that can be rapidly rotated and provided with diamond cnttsrs, so arranged that while each cutter removes material and traces a path over the moulded surface to be produced, all the cutters produce wronght aurfaces free from distinct scratches. For cutting mostly on a horizontal face, the head is solid in which the diamonds are mounted. For moulding on an edge, the cutterbead holds bits of ateel studded with black diamonds. A rotary tool is shaped to finish the groove, and preferably formed of brass. For cutting as with a saw into marble a small round vertical spindle is used, the surface of which is studded with black diamonds or carbon points, so arranged in rows that the ontting points of the different rows merge their paths of action, so as to cut the whole length of the cutting plane of the ahaft. Imrratron LeaTHer.—For producing imitation morrocco or other leather, a foreign exchargo recommends a composition consisting of one pound of glue to five liquid ounces of glycerine, boiled linseed oil being added for flexibility, or India rubber for elasticity, together with the coloring matter. Thecomposition.is spread while hot upon the fabric, and impressed with the design. The hardened impressed surface is treated with a solntion of alum or chromo or other alum, or with a solution of sulphate of iron, cépper or zinc. The alum or sulphates may be mixed with the composition before it is apread. The surface is protected by varnish or waterproof composition, and ornamented by gold, bronze, or other coloring material. Yuu Henperson Iron Process.—Samples of iron made by the Henderson fluorspar process have recently been tested in England. The breaking strength was found to be 28 tons per square inch, the Government Standard being og tons, ‘(ue unusual activity in the British iron market still continues. The proprietors of iron and coal mines are reaping a rich harvest,

June 15, 1872.] SCIENTIFIC . BRESS. §oientiric Proaress. A Waning Star. In our last issuo we made refersnec to the disappearanco of the star, Eta Leonis [the printer made us say Mu Leouis]. Sinco that peragraph appeared we have seen a note from Geo, Madeira, of Santa Cruz, who, having examined this star with, probahly, a more powerful telescope thau tho San Francisco observer, reports that on the Ist iustant it waa fast diminishing in brilliancy hut had vot at that timo disappeared entirely. Mr. M. promises to continue his observatious for a few weeks and give the public an accouut of the same. Such phenemena as tho disappearance of a star or any variation in a star ick has hitherto waintained a permanent degree of luminosity, are of very rare occurrence and perhaps, a short reference to the more uoted phenomena of this kind which have heretoforo been uoticed may ho appropriate in connection with the one which is now attracting the atteution of astronomers. During tho last 2,000 years there have been noticed some 20 ‘‘tomporary stars,” which havo auddenly made their appcarance in the hea veus only to hlaze out or tlicker awhile and finally to disappear entirely. Of the variuble stars, which iucrease and dimiinish their light periodically, only ahout 24 have boen thus far recorded. The first variablo star, Mira in the constellation, Celus, was uoticed in 1596. Snbsequent observations have shown that this star hasa periodicity of about 332 days, during which time it increases from total obscurity to a star of the secoud magnitude. Wheu decreasing, it changes its color from white to red. Seventy-three years afterwards, the noted star Argol (the demon star) was observed to be variable, It passes through its variations from the 2d to the 4th magnitude, and vice versa, overy sixty-eight hours, Tho star Cephas, makes its changes from 3d to 5th ningnitude, in about 5% days. The most wonderfnl of the temporary stars, was seon in 1572, It appeared suddenly in the constellation, Cassiopea, and very soon renched the brightness of Sirins, after which it increased in brilhancy until it surpassed ovon Jnpiter or Venus, and could even be seen in the day-time. Its period of increase was abont one month; but its period of waning was very gradual—tasting about fifteen months. Thia star was first white, then red and finally white again. Somo astronomers think that this is a variahle star of long period—about 313 years, from the fact that asimilarappearance was observed in the same portion of the heavens in 945 and again in 1264. Its anthentic appearance having been in 1572, if the surmise of its periodicity is correct its next appearance will be in 1885. The most remarkable temporary star of recent times was the one which suddenly blazed out with a brilliancy of the 2d magnitnde, on the 12th of May, 1866, in the constellation of the Corona Borealis. In its place, previously, had been recorded a telescopic star of the 10th magnitude. The sudden appearance of this star created quite an excitement in thescicntific world. It was carefully investigated by Hnggins with the spectroscope, who arrived at the conclusion that the star owed its sudden brightness to the evolution of flaming hydrogen. It was naturally supposed that such an active conflagration of. that matter could not be of long continuance, and that its exccssivo brilliancy would soon fade away; a prediction which was fully verified, as tho hydrogen lines disappeared in tite spectrum in abont eight days. Itrapidly waned to the 6th magnitnde, and more gradually from that to the 10th—its original record. Since 1868 it fluctuates slightly, but singularly, unlike the ordinary variable stars. In 1870 it was of the 7th magnitudc, and now it shines with the 8th. The variations of the pcriodically variable stars are generally thought to be due to the fact that they are double stars, revolving around a common centcr—onc being brighter than the other. In cases of total temporary disnppearauce, one star may be totally devoid of light. Again “sun spots’? may in somo cases account for the phenomena of waxing and waning. Tn that sense the center of our solar system— the sun— is a periodically variable star of elevcn years time—that being the period of its presentation of a greater or less;number of ‘‘sunspots.” With the later improvements and better understanding of the spectroscope, great advance is now being made in astronomical knowledge —particularly in relation to the physical condition of the heavenly hodies. Spectroscopic observations on the star Eta, which jnst now seems to be gradually flickering itself ont of our view, willbe looked for with much interest. Tse CrysTALLization oF Iron AND STEEL.— The various qualities of iron and steel may be compared by observing the forms of their crystals through a microscope. Cast steel of fine quality exhibits fine crystals of a needle-hke shape parallel to each other; and the axes of these crystals are in the direction of the hammering to which the metal has been subjected. The surface of iron exhibits crystals of the shape of a double pyramid, the proportions varying with the quahty of the metal. The pyramids more nearly approach a cubical form as the carbon in the metal is increased in quantity. Measuring the Light of Stars. Zoelner, of Berlin, has recently made an important addition to the means by which tho astronomer sevks to measure the degree of light emitted from a star. The small quantity of light which reaches us froni these distant bodies, renders the look ef measuring the same by the instruments heretofore in nse extremely difticult. The invention of Mr. Z., is a polariscopo connected with a tclescope. i this iustrnment, a ray of light is made to disappear and reappear altetuately, by simply turniug an eyepieco of Iceland spararound Its axis, throngh an augle of 90°, This disappearance and reappearancs is gradual, and the angle of rotation from 0° to 902, may therefore be nssd as & measnre of the intensity of the light—the stronger the light, the greater the rotation reqnired to be toned down toacertain standard. Important results have already been obtained by tho use of this instrument. One of tho most important results of this instrumeut, is the power which it givss of mors accurately determining the periods of the variable stars. Heretofors it has been so difficult to measure the intensity of ths light from a star, it was quite imposaibls to detect with even much approximate accuracy, tho preciss timo oceupied hy a star in passing from ita period of Isast light through its gradual increass and subsequent decrease of light, again to ita point of least brilliancy. Rostnornite, A New Foss. Resiy.—A new fossil resin, named rosthornite, is describsd by Hofer as occuring in the coal of the Sonueberg, in Cariuthin. This has a fatty lustre, a brown color with garnct-red gloss, wins-yellow hy transmitted light, and a light brown to orange yellow strenk. When heated in the air it gives off white vapors having an aromatic odor, and burns with a smoky flame without leaving any residue, In chemical composition this mineral approaches most nearly to enosmite, and atill more to the fossil resin of Girona, in New Grenada. This substance cau not be properly assigned to auy of the groups already established amoug the fossil resins, but scems rather to conform to the type of a solid resin, rich in carhon but poor in oxygen. Tne spectrum of hydrogen has been recent ly made the subject of experiment by Prof. Angstrom ; he states that it prescnts only four lines, and consideres that the other spectra that have been given arein error from the presence of impurities. Ho also examined the spectra of atmospheric air under different degrees of rarefaction, and fouud that at first it was that of air; then of nitrogen; then of carbonic oxide ; and when the exhaustion had reached its utmost limit the spectrum obtaincd was that of sodium and chlorinc. Coativo Metats wire Nicken ny THE Motsr Wax.—According to C. Mene, wrought and cast-iron, steel, copper, brass, zinc, and lead ean be coated with nickol by putting theso metals, or objectsamade of them, ina boiling nentral solution of chloride of zinc, to which a salt of nickel is added, and also zinc, in a grannlated state orin sheets. If the solution be acid the coating will be dnll. When, instead of a salt of nickel,.ono of cobalt be used, a coating of that metal may be obtained. Manrvets or THE Microscorzr.—A beautiful and easily produced exhibition of crystal formation may be seen under the microscope as follows: Upon a slip of glass place a drop of liquid chloride of gold or nitrate of silver, with a particle of zinc in the gold and copper in the silver, A growth of exquisite gold or ailver ferns will vegetate under the observer’s eye. A Sociuty or Ants, Sciences and Letters, has just been started at Winona, Minn., in connection with the first State Normal School in that place, having for its object tho collection of facts and materials looking toward the determination of tho natural history, archmology, and general literature of the United States. Ayorner Sincinc Fuamz.—aAt a late session of the Philosophical Society of Glasgow, held lately, Dr. A. Irvine showed some experiments on a new variety of singing flame, and described and experimented with a new miner’s safety-lamp, which involves the application of that flame. The experiments excited a great amount of interest among the members. Artirican Musx.—Prof. Vander Weyde, at a late meeting of the Polytechnic Association of tho American Institute exhibited an artificial musk, made by treating blood in a peculiar manner. By adding little hairs, such as are found in gennine musks, the’ deception is so complete that it cannot be detected even by the microscope. Waeataer Prepictions.—President Tillman, of the Polytechnic Association of the American Institute, says the weather predictions which are daily published in our newspapers have been verified to about 75 per cent.; that is, three-fourths of all the predictions which they have made have been fonnd te be true. Tue British Socicty for the Advancement of Art still offer the $5,000 reward for a pigment or covering which will perfectly protect iron

from rust and fouling. M. Cuampounton avers that pntrifaction is much more rapid in the dead bodiea of those who have used alcohol to excess than in those of comparatively sober individuals, Ni ECHANICAL Proaress Granite Works of the Ancients. The following, from an exceedingly interesting account of the colossal granite structures of aucieut Egypt, India and South America, appearsin the curreut number ef the People’s Magazine — The art of earving in granite has never heen earried to higher perfection than on the continent of India, At Chillambaraiu, also in the Carnatic, and on the Coromandel coast, is a congeries of temples, representing the sacred Monnt of Meru. Here are seven lofty walls, one withiu the other, round ths central quadrangic, and as many pyraiuidal gateways in the midst of each side, which form ths limhs of a vast cross; consisting altogetber of twenty-eight pyramids. hero are consequently feurtceu in a linc, which extend more than a mile iu one coutinueus direction! Nor are these the only wonders associated with this metropolis of pyramids. The interior ornaments are in harmouy with the whols; from the nave of one of the principal structures thsre hang, on the tops of four buttresses, festeons of chains, in length about 548 feet. Each garland, consistiug of twenty links, is made of ono piece of granits, sixty feet long; the links themselves ars monstrona rings, thirty-two inches in cireumferencs, and 4 as smooth as glass. Compared with ths monolith temples of granite at Mahabaiipuram, which is likewise situated on tbo Coromaudel coast, thoso in Egypt sink into insignificance. The rocks thercabouts are composed of a hard gray granite, containing quartz, mica, and feldspar, with a few crystals of hornblende interspersed. Many have been hollowed out by art, and seulptured into temples with spirited bas-reliefs, representing episodes in Hindoo history and mythology, and supported by graceful colnmns; all carved from the solid rock. Detached masses havo been cut into shapes of elephants, tigers, Hons, bulls, cats, monkeya, and yarions nondescript monsters, and colossal statucs of gods, one of which; namely, that of Ganesa, being thirty fcet high. “The southernmost of the temples is abont 40 ft. in hight, 27 ft. in breadth, and nearly the same in length; the exterior being covered with elaborate sculptures. The adjoining edifice is about 49 ft. in length, and in breadth 26 ft.; it is rent by natural causes from summit to base. According to the local Brahminical tradition, these wonderfn] sculptures were executed by 4,000 workmen, who had come from the north, and returned before their completion. From a eareful examination, it is evident that almost all the enormons mass of sculpture and carving that adorns this city of monolith temples and colossi, must have been performed withont the aid of —with the hammer, chisel, lever, and wedge alone; and this is one of the hardest rocks in the world?” A Sxont Coat Supriy.—A correspoudent in Engineering saysthat almost any price can be had for coals in the north of England, by those who are fortunate enough to have any for sale. The demand is so heavy that the additions which are being made to pits, and the new pits which are being sunk, seem to go but a very little way in meeting the extra requirements of consumers. Everybody is crying ont for more fuel, and, do what they will, they cannot get it quick enongh. To meet this extraordinary increasing demand, hand labor is inadequate. Good coal-cutting machines must be forthcoming. The attention of a great many engineers are directed to this qnestion of coal cutting, and, in this age of invention, it will be remarkable if suitable machines are not soon introducod. Unless machines aro applied to coalcutting, there isnot the slightest doubt that the iron trade and other industries will be crippled in their development for want of fnel. Goal being scarcer, there is, of course, the greatest difficulty in obtaining coke. Anturictan LeatHer.—Among the different kinds of artificial leather lately introduced, is tho following:—-J, Charles, in London, and C. Taylor, in Manchester, England, take boiled linseed-oil, and boil it again with quicklime and borax, till they obtain a finid, which, by cooling, nearly solidifiss into a thick dough. To this they add pniverized cork, and some quicklime, and the paste obtained is rolled out into sheets, which, if desired to be very smooth, after being dried, and rubbed down by means of pumice-stone. The process is evidently a partial sponification, and reminds ua of the artificial India rubber, which is also made of linseed-oil, withont the addition of the powdered cork, which serves only to give the ge of leather, and is a mere filling or adulteration of the tenacious chief ingredient, in the same way as India rubber is adulterated by similar fillings. Puppuine Furnaces 1x Grear Briran.— There are about 7,800 pudding furnaces in Great Britain, employing 26,000 men, involying an investment of over $5,000,000. All these furnaces are now worked by hand, or at least with but trifling help from mechanical device. It is expected that a revolution will soon be wrought out with this immense industry, by use of the mechanical puddlers, which have already been proven snecessful in their application. Improvement of the Steam Engine. In a paper read before the Polytechnic Association of the American institute by Professor Thurston, on the ahove subject, he snmmed up his conclnsions iu the following statsments: The direction which improvement seems now to be taking, and the proper direction, ns iudicated by an examination of tbe principles of scieuce, as well as hy our review of the steps already taken, seem to he: Steam must enter the machine at the highest possible temperature, must bo protected from waste, and must retain, at the moment befors exhaust,theleast possibleamountofheat. He whose inventive genius of mechanical skill contributes te effect either ths use of highsr steam with safety and without waste, or the reductiou of the temperature of dischargs, confers a boou upon mankind. Tu detail: In the engine, ths tendency is, and may probably bs expected to coutinue, in ths near future at least, toward higher steem pressure, greater expansion in wore than one eylinder, steam jacketing, superheating, a careful use of non-conducting protectors against waste, and ths adoption of higher piston speeds. In the boiler, more complete combustion withont success of air passing through the furnace and more thorough ahsorption of heat from the furnacs gases. The latter, I am inclined to suppose, will be nitimately effected by the uso of a mechanically produced dranght, in place of the far more wasteful method of obtaining it hy the sxpenditure of heat iu the chimney. ‘ In construction, we may anticipate the nss of better materials and mors careful workmanship especially in the boilsr, and much imPE in forms and proportions of details. In management, there is a wide field for improvement, which improvement we may feel assured will rapidly take place, as it has now become well uuderstood that great care, skill and intelligence are important essentials to the economical management of the steani engine and that they repay liberally all of the expense in time and money that are requisito to aecure them. A New Kip or Frov1t-Grass.—Dr. Benrath, Director of the glassworks at Dorpat, Russia, publishes an account of experiments made by him to produce a glass which has the good qualities of flint-glass without its defects, ‘The good qualities of ordinary flint-glaas are, that it is as clear as crystal; that it has a high specific gravity, (is heavy;) a low fusing point, so that it melts easily; and strong power of refraction and dispersing light. Itis, therefore, invaluable for chemical and optical purposes. Its defects, however, are that it is easilyacted on by chemical and mechanical influences—that means ita surfaco cannot stand rain and sunshine, much less acids or boiling water, and it is so soft that it is most easily scratched. The chemical difference between ordina) and flint-glass is that the former consists of silex, lime, and soda or potash, while oxide of lead is added to make flint-glass out of it. Chemically speaking, common glass is a silicate of lime and potash; while flint-glass contains also silicate of lead. Corrina Marnie.—A recently devised foreign .apparatus for stone-eutting uses comprises.a hoad that can be rapidly rotated and provided with diamond cnttsrs, so arranged that while each cutter removes material and traces a path over the moulded surface to be produced, all the cutters produce wronght aurfaces free from distinct scratches. For cutting mostly on a horizontal face, the head is solid in which the diamonds are mounted. For moulding on an edge, the cutterbead holds bits of ateel studded with black diamonds. A rotary tool is shaped to finish the groove, and preferably formed of brass. For cutting as with a saw into marble a small round vertical spindle is used, the surface of which is studded with black diamonds or carbon points, so arranged in rows that the ontting points of the different rows merge their paths of action, so as to cut the whole length of the cutting plane of the ahaft. Imrratron LeaTHer.—For producing imitation morrocco or other leather, a foreign exchargo recommends a composition consisting of one pound of glue to five liquid ounces of glycerine, boiled linseed oil being added for flexibility, or India rubber for elasticity, together with the coloring matter. Thecomposition.is spread while hot upon the fabric, and impressed with the design. The hardened impressed surface is treated with a solntion of alum or chromo or other alum, or with a solution of sulphate of iron, cépper or zinc. The alum or sulphates may be mixed with the composition before it is apread. The surface is protected by varnish or waterproof composition, and ornamented by gold, bronze, or other coloring material. Yuu Henperson Iron Process.—Samples of iron made by the Henderson fluorspar process have recently been tested in England. The breaking strength was found to be 28 tons per square inch, the Government Standard being og tons, ‘(ue unusual activity in the British iron market still continues. The proprietors of iron and coal mines are reaping a rich harvest,