Volume 23 (1871) (426 pages)

364 SCIENTIFIC PRESS. {December 9, 1877, IP ECHANICAL Procress Audacity in Invention. As arule, nseful inventions are ths offspring of the most delihersts calculation, and their practicahility is likely tohein the ssms ratio as their correspondence with the teachings of experience. Sometimes, howsver, as if to confound the wise, there occurs a marked exception to the rule. Among these was ths exsmpls of a ateel headsd rail, now quite extensively adopted. For years an effective method of welding a steel top to an iron weh hsd heen sought in vain, until an audacious inventor proposed to put them together without welding. The steel cap was simply so shaped that the pressure of the train would tend to converge its lateral portions upon the web helow. Few helieved that the plan would work; hut practice showed that the jarring concussions of the wheels that hsd knocked the caps from other compound rails hut hammered this the closer to its plsce, and so a daring thought and hold experiment counted for more than ths most careful consideration would have done. In another instance an inventor evolved from his innsr consciousness a plan o: setting the looss tires of wagon wheels wihout removing and heating them, as had heen previously done in tire-setting machines. Hs proposed to compress an iron strap around the tire without taking it from ths felloes, and hy thus upsetting ths mstal upon itself diminish the dismeter of the tirs until it cams firmly and fixedly to its place. Most people would say thst to thus npset cold iron would tske more power than could be conveniently applied to ths apparatus. Butthe inventor, nothing daunted hy ths spparent difficulty, tightened the iron-compressing strap with a four-foot lever and a two-inch screw; found ths experiment a complste success, and huilt up a prosperous husiness upon ths pstent hy which he sscured the improvement. Examples liks these, whils they should not lead to hare-hrained enterprises, are sufficient to show that sometimes, at least, a little courage gives hetter results in invention than placid and cautious ‘‘common ssnse,”—.American Artizan. Tron Steampoat BuILDINO ON THE MissisSIPPI.—The question of huilding iron steamhosts, to take ths place of wooden ones now plying on our Western rivers, is heginning to receive serious consideration. <A correspondsnt of the St. Lonis Democrat, writing from Chester-on-theMississippi, says thst an agent of an English company, from London, not long since visited that locality with a view to the estahlishment of a yard to huild iron steamers. The location is on the Illinois shore, hut forty miles away from the great iron fields of Missouri, and with the water lower in the Mississippi than has heen known since 1838, there is now a depth of thirty or forty feet for a distance of at least one and a half miles the whole width of the river. It is claimed that “with the necessary facilities,” iron stéamers can he as cheaply huilt there as anywhere in the United States, or even on the Clyde. Arrangements are said to he now making for the manufacture of iron, and practical men, who expect to invest millions of dollars as fast as the work can he prosecuted, say that iron can he made at Chester $10 per ton less than at any other place in the United States. When this fact shall have heen satisfactorily demonstrated, the destiny of the place will he settled beyond question. ; : THe Ropwrwe or Guxzoats—A New Fact Estaniisnep.—The British gunhoats Busiard and Kite were recently suhjected to experiments in order to test their rolling motion in a sea way, and discover, whether it is easier with the eighteen-ton gun in its position on the platform level with the fore deck, or when it is lowered into the well heneath; and, although the weather was not sufficiently rough to subject the the vessels to a ssvere test, yet the result showed that they are much steadier when the gun is up in its position than when it ishelow. The Bustard, with her gun on deck, made only eleven rolls per minute, and the greatest roll was from 7° to port (leeward), to 4° to starhoard (windward), hut with the gun helow she made fourteen rolls per minute, the greatest roll being 9° to port to 13° to starhoard, heing three rolls per minute more with just twice the amount of heel. A similar result was ohtained with the Nite. Chapin’s Transparent Waterproof Varnish. The amount of lahor required to kesp finished machinery untarnished, renders 2 transparent waterproof varnish very desirahle. Ina recent visit to ths Collins Co’s. works, at Collinsville, Conn., we found them using such a varnish on their polished plows, to prsvsnt rust in transportation. Inquiring as to its efficiency, we found that whereas hefors using it they had heen at great trouhle and expense in rspolishing after transportation, sincs_ its use ths difticulty hasheen entirely ohviated. As an illustration of its efficacy, ws were shown s machete, or Spanish knifs, ahout two fset long and two inches hroad, one side of which had hesn varnished. This had heen repeatedly plungsd into salt water and dried, when it was found thst on ths varnished side the polish was as bright as ever, whils the opposite side was covered with a thick coat of rust, making it almost impossihls to rsalize that it was evsr polished. Ws also saw portions of the varnish removed hy a solution of pot ash and water from polished plows, which had heen on mors than two years, showing as hright a polish as ever. For the transportation of machinery or any polished metal this varnish is invalua{. his, as it does away with ths use of white lesd and other suhstances now employed which impair ths appearancs of ths metal snd injure ths finish. In point of economy itis desirahle, as ons gallon will cover more surface than several gallons of white lead slush, and is, at ths same time, far more easily removed. By ths use of this varnish, machinery can hs kspt hright with a much Isss outlay of time, and will look nearly as well ss an unvarnished surface, and, certainly, much hetter than most mschinery is kept. Itis claimed that it is equally valuahle for any surfacs exposed to ths weather. It also renders paper or cloth perfeotly water proof and, st the same time, transparent. C. Y. Chapin & Co., Collinsvills, Conn., are the manufacturers.—Jron Age. InpuRATION oF Woop.—Wood for nse should hs guarded against two sources of destruction, decay and abrasion. For the first, thsre ars numerous efficacious prevsutives, differing in character and cost; for the other thers is at present none that can he relied upon. Wood hss heen saturated with a chemics] suhstance in snch manner that, when impregnated with a second, a solid suhstance would he dsposited in the pores, therehy sscuring induration and consequent hsrdening. This process, whatever ths chemicals used, is most efficiently carried into practice hy forcing the chemicsls in solution lengthwise through the wood hy hydraulic pressure. We helisve that experiments in this line, if successful, would lead to important public henefits, and also prove remunerative to the inventor. As the material would he hoth water-proof and _fireproof hy the process, there would he many uses other than that designated to which it could he advantageously applied in engineering, and more than in one department of the arts.—American Artizan. How toe Frenog Burtp.—The French practice in huilding isagood one. Instead of using flimsy lath for thin partitions, they employ stout pieces of oak, as thick as garden-palings. These they nail firmly on each side of the framing of the partition, and fill the space hetween with rubhle and plaster of Paris. They coat the whole with the plaster. The floors are managed in the same way, as well as the under side of the stairs. Honses are thus rendered as near ‘‘ fire proof” as if huilt of stone throughout. Nottingham, England, where they have gypsnm in the neighhorhood, as in Paris, they form their floors and partitions in the same solid manner; consequently a huilding is rarely hurned down in that populous manufacturing town. A new horse shoe has come into general use in Paris. Itis imperfeotly descrihed as heing a “‘ narrow rim of iron, which gives perfect protection to the edge of the hoof, without cramping its sole.” It is said to require much less weight of metal, and therefore is cheaper. Though not specified, we suspect that nails are not used. Itis said to give great satisfaction —it is called the Chanlier Horse-shoe. SHaping Meraus—Sometaino New.— In a process lately proposed for shaping mstals, a mold is made in sections to suit the article required, and a sheet of metal is placed in it, after which a cover is clamped on to the mold, and water pressure is conveyed to the interior hy a pipe, wherehy the metal is expanded to the counterpart of the mold. §clENTIFIC Progress. x Are Men to Fly. Darwin tells us that sven in the upper region of ths air, near the summits of the Andes, vulturea msy he seen flosting onward for miles upon motionlsss wings. What is the secret ofthis flotation? Gravitation acts as forcihly on the suhstance of . the bird as on thst ofthesnimal. Nor can we hslieve that thers is any huoyancy, properly so called, in the hird’s hody or wings. Those vultures, which seemed to float steadily through still air, must have received support from the air in one or mors of the three several ways. Hither by swift motion, acquired hefore the floating begsn and slowly reduced through ths sffects of aerial resistance, or hy ths action of aerial currents through which they were esrried, or else, while seeming to float horizontslly, they were in reslity traversing a slightly sloped descending psth. Neither of ths two ;former explanations seems availahls, hscauss the floating motion is continued so long that the frictional resistsncs of ths air would almost certainly havs destroyed a largs share of the origins] motion through ths air. This would equally happen whether the hird had in the first plscs urged its way swiftly through the air, or hsd floated itself off, so to speak, upon a swiftly moving air current. On the otber hand, there would seem to bs no valid objection against the third explsnation; for a single observer, at rest, would have no means of determining whether a hird was sailing along horizontslly, or gliding down agentls incline. Butit matters littls which explanation of ths three wo excspt as the most plausihls. Ths point to hs chiefly noticed is the fact that, a hsavy hody—for ths vulture is no chicken, so to speak—can bs sustained, for long distsnces, merely by the supporting action of ths air. Thers can he little douht that it is only on account of the psrfect steadiness of their motion through the air that they ars thns supported. ‘The efforts of aeronautics] mechanicians must he directed to securs a similar steadiness of motion for asrial facilities. Granted this, there csn be no reason why the powers of stesm and iron should not avail to secure an aerial motion sven surpassing in rapidity the flight of ths swiftest birds. Unlsss we are willing to helieve that hirds fly hy some power distinct from any which physical ‘science deals with, we seem justified in helieving that the hird may he matched, or surpased, hy the flying machins, as surely as the swiftest animals are surpaased hy ths locomotive. It is enceuraging to consider that ths actual amount of power necessary to convey 8 weight through ths air (if that support is derived directly from the air), is very mnch less than that required to convey the same weight hy sea or land. In ths presence of failing coal supplies, this consideration will one day assume first-rate importance. Spectator. Scrence rn AoRICULTURE.--A writer in the Western Rural makesthe following sensihle remarks: ‘‘The sooner we throw away the phrase Science 9f Agriculture, and suhstitute Science ix Agriculture, the sooner we shall he on the high-road to scientific farming. It rests upon all science, taking only a portion here and there, just as the animal crops the herhage as he passes along. He can live and even grow fat upon hut few varieties, hut for his fullsustenance craves many. So of the farmer. He can get along hetter than any other profession with hut little knowledge except that of mere art. The moment he reaches after that higher knowledge, it should he in such directions as will enable him to profit by it. ‘The principles of science, and not the hare manipulations of art,’is what he should attain; hnt as a practical man, science, only so far as it may hear upon, or can he applied to his practical art.” Freezino BY Mrcaanicat Action.—M. Foselli has announced to the French Academy of Science that he had succeeded in producing an amount of cold just helow the zero of the Fahrenheit scale, hy simple mechanical action creating rapid evaporation. He employs a wheel formed of a spiral tuhs, hoth ends of which are open, set vertically and half immersed in the fluid to he cooled, so that the latter passes constantly through the whole length of the tuhe, half of which is constantly ahove the liqnid, and heing wet gives rise to active evaporation and consequent refrigeration within it. The evaporation is increased hy a small fan. The principle of which M. Foselli here avails himself is of course well known, hnt the multiplication of the point of evaporation hy mechaniéal srrangemsnt according tothe method which he has originated, is certainly ingenious; and in hot, dry weather, even a disc of iron tnrning pepidly in liquid would produce refrigeraion.Another Grand Scientific Project. Among the most noticesble events in ths progress of science, at the present time, is ths efforts that ars heing made to notice ths water and sir forces at work on various portions of the earth, to so arrangs and present them tothe world ss toenahle man to avoid ths dangers which they threatsn, or take such direct advantages of the forces themselves ss to maks them suhservient to his interests. We have noticeable instaness of progressin this direction in Maury’s charts of ocean currsnts, his puhlications with regard to the laws which govern air currents or storms, and ths great work in which the U.S. Board of Topographical Engs. arenow engagsd in making daily reports upon ths temperature of the atmosphers, position of the baror eter, and direction of air currents, stc., throughout ths United States. The ahove work has thus far heen mors or less limited in its scops and ussfulness, having hesn confined moatly to the territory of the United States and ths seas, gulfs and oceans which surround thsm. But now ws hear of another snd still grander project, proposed hy Lieut. Maury, for noticing ths forces at work on the entirs face of the glohs, and distrihuting the information ohtsined for the hsnefit of producers snd mankind in genersl. Hs proposes, with the aid and co-operation of ths yarious Governments of the world, and ths uss of all ths appliancs of stesm and electricity, to estahlish a vsst system of weather and crop ohssrvations and reports, which shall keep producers in all lands informed of whst is going on all over ths glohe, so that thsy may know wherewith thsy'are competing and what their prospects are in the market. “Tn this age of steam and rapid communication” remsrks a cotsmporsry, ‘‘the graingrowsr of Tlinois is a competitor of the grsin-growsr of the Danuhe, and ths cotton-plsnter of Georgia must measuys ths vslus of his crop hy the products of the fields of India and Egypt. That this measure may hs accurately mads as the seasons advance, Prof. Maury has projscted the scheme referred to. He helieves that mau hss already in his hands powers and agencies which will enahls the grain-grower of ths West and ths cotton-planter of the South to know, as ths season progresses, the prohahle supply of the stapls in which he is intsrested in all quarters of ths globs, and when the times of harvest come in ths different climes, to hs informed with approximate precision of actual quantitiss sent into the market. The henefits of tho scheme are apparent; its practicability is no more donhtful than of many other great undertakings which have heen carried through to success seemed to he when they were first projected.” Frost Work Imitated, Among the curiosities of recent scientific discovery, may he instanced that made hy M. Bertsch, and turned to practical account hy M. Kuhlmann, ths celehrated chemist. M. Bertsch has found that Epsom salts, or sulphate of magnesia, dissolved in heer, together with a amall quantity of dextrine, or artificial gum, applied toa pane of glass with a hrush, will, on crystallizing, produce the identical designs formed on the glass hy frost in cold weather, with this improvement, that the liquid may receive any color whatever, at the option of the operator. M. Kuhlmann, however, conceived the idea of going a step further, and transferring those fairylike creations to stuffs and papers. By means of a powerful hydraulic press, the minutest details of the figures in qnestion were duly imprinted on the soft metal, and a cony of them in relief was then ohtained hy galvanoplastics. But in the impression of cotton stuffs, the patterns mnst ho continuous, whereas in M. Kuhlmann’s plates the lines at one end would fail to coincide with those at the other, cansing disagreeahle interruption in the printed designs. To overcome this, he ingeniously effected the crystallization of the cylindrical snrface of aroller. A slight rotary motion imparted to it, prevents the liquid from accnmulating at any particular point hefors it is evaporated. Srinver stains may he removed hy hleaching with chloride of copper, and then washed ont with hyposulphite of soda, and afterwards with water. aa -

364 SCIENTIFIC PRESS. {December 9, 1877, IP ECHANICAL Procress Audacity in Invention. As arule, nseful inventions are ths offspring of the most delihersts calculation, and their practicahility is likely tohein the ssms ratio as their correspondence with the teachings of experience. Sometimes, howsver, as if to confound the wise, there occurs a marked exception to the rule. Among these was ths exsmpls of a ateel headsd rail, now quite extensively adopted. For years an effective method of welding a steel top to an iron weh hsd heen sought in vain, until an audacious inventor proposed to put them together without welding. The steel cap was simply so shaped that the pressure of the train would tend to converge its lateral portions upon the web helow. Few helieved that the plan would work; hut practice showed that the jarring concussions of the wheels that hsd knocked the caps from other compound rails hut hammered this the closer to its plsce, and so a daring thought and hold experiment counted for more than ths most careful consideration would have done. In another instance an inventor evolved from his innsr consciousness a plan o: setting the looss tires of wagon wheels wihout removing and heating them, as had heen previously done in tire-setting machines. Hs proposed to compress an iron strap around the tire without taking it from ths felloes, and hy thus upsetting ths mstal upon itself diminish the dismeter of the tirs until it cams firmly and fixedly to its place. Most people would say thst to thus npset cold iron would tske more power than could be conveniently applied to ths apparatus. Butthe inventor, nothing daunted hy ths spparent difficulty, tightened the iron-compressing strap with a four-foot lever and a two-inch screw; found ths experiment a complste success, and huilt up a prosperous husiness upon ths pstent hy which he sscured the improvement. Examples liks these, whils they should not lead to hare-hrained enterprises, are sufficient to show that sometimes, at least, a little courage gives hetter results in invention than placid and cautious ‘‘common ssnse,”—.American Artizan. Tron Steampoat BuILDINO ON THE MissisSIPPI.—The question of huilding iron steamhosts, to take ths place of wooden ones now plying on our Western rivers, is heginning to receive serious consideration. <A correspondsnt of the St. Lonis Democrat, writing from Chester-on-theMississippi, says thst an agent of an English company, from London, not long since visited that locality with a view to the estahlishment of a yard to huild iron steamers. The location is on the Illinois shore, hut forty miles away from the great iron fields of Missouri, and with the water lower in the Mississippi than has heen known since 1838, there is now a depth of thirty or forty feet for a distance of at least one and a half miles the whole width of the river. It is claimed that “with the necessary facilities,” iron stéamers can he as cheaply huilt there as anywhere in the United States, or even on the Clyde. Arrangements are said to he now making for the manufacture of iron, and practical men, who expect to invest millions of dollars as fast as the work can he prosecuted, say that iron can he made at Chester $10 per ton less than at any other place in the United States. When this fact shall have heen satisfactorily demonstrated, the destiny of the place will he settled beyond question. ; : THe Ropwrwe or Guxzoats—A New Fact Estaniisnep.—The British gunhoats Busiard and Kite were recently suhjected to experiments in order to test their rolling motion in a sea way, and discover, whether it is easier with the eighteen-ton gun in its position on the platform level with the fore deck, or when it is lowered into the well heneath; and, although the weather was not sufficiently rough to subject the the vessels to a ssvere test, yet the result showed that they are much steadier when the gun is up in its position than when it ishelow. The Bustard, with her gun on deck, made only eleven rolls per minute, and the greatest roll was from 7° to port (leeward), to 4° to starhoard (windward), hut with the gun helow she made fourteen rolls per minute, the greatest roll being 9° to port to 13° to starhoard, heing three rolls per minute more with just twice the amount of heel. A similar result was ohtained with the Nite. Chapin’s Transparent Waterproof Varnish. The amount of lahor required to kesp finished machinery untarnished, renders 2 transparent waterproof varnish very desirahle. Ina recent visit to ths Collins Co’s. works, at Collinsville, Conn., we found them using such a varnish on their polished plows, to prsvsnt rust in transportation. Inquiring as to its efficiency, we found that whereas hefors using it they had heen at great trouhle and expense in rspolishing after transportation, sincs_ its use ths difticulty hasheen entirely ohviated. As an illustration of its efficacy, ws were shown s machete, or Spanish knifs, ahout two fset long and two inches hroad, one side of which had hesn varnished. This had heen repeatedly plungsd into salt water and dried, when it was found thst on ths varnished side the polish was as bright as ever, whils the opposite side was covered with a thick coat of rust, making it almost impossihls to rsalize that it was evsr polished. Ws also saw portions of the varnish removed hy a solution of pot ash and water from polished plows, which had heen on mors than two years, showing as hright a polish as ever. For the transportation of machinery or any polished metal this varnish is invalua{. his, as it does away with ths use of white lesd and other suhstances now employed which impair ths appearancs of ths metal snd injure ths finish. In point of economy itis desirahle, as ons gallon will cover more surface than several gallons of white lead slush, and is, at ths same time, far more easily removed. By ths use of this varnish, machinery can hs kspt hright with a much Isss outlay of time, and will look nearly as well ss an unvarnished surface, and, certainly, much hetter than most mschinery is kept. Itis claimed that it is equally valuahle for any surfacs exposed to ths weather. It also renders paper or cloth perfeotly water proof and, st the same time, transparent. C. Y. Chapin & Co., Collinsvills, Conn., are the manufacturers.—Jron Age. InpuRATION oF Woop.—Wood for nse should hs guarded against two sources of destruction, decay and abrasion. For the first, thsre ars numerous efficacious prevsutives, differing in character and cost; for the other thers is at present none that can he relied upon. Wood hss heen saturated with a chemics] suhstance in snch manner that, when impregnated with a second, a solid suhstance would he dsposited in the pores, therehy sscuring induration and consequent hsrdening. This process, whatever ths chemicals used, is most efficiently carried into practice hy forcing the chemicsls in solution lengthwise through the wood hy hydraulic pressure. We helisve that experiments in this line, if successful, would lead to important public henefits, and also prove remunerative to the inventor. As the material would he hoth water-proof and _fireproof hy the process, there would he many uses other than that designated to which it could he advantageously applied in engineering, and more than in one department of the arts.—American Artizan. How toe Frenog Burtp.—The French practice in huilding isagood one. Instead of using flimsy lath for thin partitions, they employ stout pieces of oak, as thick as garden-palings. These they nail firmly on each side of the framing of the partition, and fill the space hetween with rubhle and plaster of Paris. They coat the whole with the plaster. The floors are managed in the same way, as well as the under side of the stairs. Honses are thus rendered as near ‘‘ fire proof” as if huilt of stone throughout. Nottingham, England, where they have gypsnm in the neighhorhood, as in Paris, they form their floors and partitions in the same solid manner; consequently a huilding is rarely hurned down in that populous manufacturing town. A new horse shoe has come into general use in Paris. Itis imperfeotly descrihed as heing a “‘ narrow rim of iron, which gives perfect protection to the edge of the hoof, without cramping its sole.” It is said to require much less weight of metal, and therefore is cheaper. Though not specified, we suspect that nails are not used. Itis said to give great satisfaction —it is called the Chanlier Horse-shoe. SHaping Meraus—Sometaino New.—

In a process lately proposed for shaping mstals, a mold is made in sections to suit the article required, and a sheet of metal is placed in it, after which a cover is clamped on to the mold, and water pressure is conveyed to the interior hy a pipe, wherehy the metal is expanded to the counterpart of the mold. §clENTIFIC Progress. x Are Men to Fly. Darwin tells us that sven in the upper region of ths air, near the summits of the Andes, vulturea msy he seen flosting onward for miles upon motionlsss wings. What is the secret ofthis flotation? Gravitation acts as forcihly on the suhstance of . the bird as on thst ofthesnimal. Nor can we hslieve that thers is any huoyancy, properly so called, in the hird’s hody or wings. Those vultures, which seemed to float steadily through still air, must have received support from the air in one or mors of the three several ways. Hither by swift motion, acquired hefore the floating begsn and slowly reduced through ths sffects of aerial resistance, or hy ths action of aerial currents through which they were esrried, or else, while seeming to float horizontslly, they were in reslity traversing a slightly sloped descending psth. Neither of ths two ;former explanations seems availahls, hscauss the floating motion is continued so long that the frictional resistsncs of ths air would almost certainly havs destroyed a largs share of the origins] motion through ths air. This would equally happen whether the hird had in the first plscs urged its way swiftly through the air, or hsd floated itself off, so to speak, upon a swiftly moving air current. On the otber hand, there would seem to bs no valid objection against the third explsnation; for a single observer, at rest, would have no means of determining whether a hird was sailing along horizontslly, or gliding down agentls incline. Butit matters littls which explanation of ths three wo excspt as the most plausihls. Ths point to hs chiefly noticed is the fact that, a hsavy hody—for ths vulture is no chicken, so to speak—can bs sustained, for long distsnces, merely by the supporting action of ths air. Thers can he little douht that it is only on account of the psrfect steadiness of their motion through the air that they ars thns supported. ‘The efforts of aeronautics] mechanicians must he directed to securs a similar steadiness of motion for asrial facilities. Granted this, there csn be no reason why the powers of stesm and iron should not avail to secure an aerial motion sven surpassing in rapidity the flight of ths swiftest birds. Unlsss we are willing to helieve that hirds fly hy some power distinct from any which physical ‘science deals with, we seem justified in helieving that the hird may he matched, or surpased, hy the flying machins, as surely as the swiftest animals are surpaased hy ths locomotive. It is enceuraging to consider that ths actual amount of power necessary to convey 8 weight through ths air (if that support is derived directly from the air), is very mnch less than that required to convey the same weight hy sea or land. In ths presence of failing coal supplies, this consideration will one day assume first-rate importance. Spectator. Scrence rn AoRICULTURE.--A writer in the Western Rural makesthe following sensihle remarks: ‘‘The sooner we throw away the phrase Science 9f Agriculture, and suhstitute Science ix Agriculture, the sooner we shall he on the high-road to scientific farming. It rests upon all science, taking only a portion here and there, just as the animal crops the herhage as he passes along. He can live and even grow fat upon hut few varieties, hut for his fullsustenance craves many. So of the farmer. He can get along hetter than any other profession with hut little knowledge except that of mere art. The moment he reaches after that higher knowledge, it should he in such directions as will enable him to profit by it. ‘The principles of science, and not the hare manipulations of art,’is what he should attain; hnt as a practical man, science, only so far as it may hear upon, or can he applied to his practical art.” Freezino BY Mrcaanicat Action.—M. Foselli has announced to the French Academy of Science that he had succeeded in producing an amount of cold just helow the zero of the Fahrenheit scale, hy simple mechanical action creating rapid evaporation. He employs a wheel formed of a spiral tuhs, hoth ends of which are open, set vertically and half immersed in the fluid to he cooled, so that the latter passes constantly through the whole length of the tuhe, half of which is constantly ahove the liqnid, and heing wet gives rise to active evaporation and consequent refrigeration within it. The evaporation is increased hy a small fan. The principle of which M. Foselli here avails himself is of course well known, hnt the multiplication of the point of evaporation hy mechaniéal srrangemsnt according tothe method which he has originated, is certainly ingenious; and in hot, dry weather, even a disc of iron tnrning pepidly in liquid would produce refrigeraion.Another Grand Scientific Project. Among the most noticesble events in ths progress of science, at the present time, is ths efforts that ars heing made to notice ths water and sir forces at work on various portions of the earth, to so arrangs and present them tothe world ss toenahle man to avoid ths dangers which they threatsn, or take such direct advantages of the forces themselves ss to maks them suhservient to his interests. We have noticeable instaness of progressin this direction in Maury’s charts of ocean currsnts, his puhlications with regard to the laws which govern air currents or storms, and ths great work in which the U.S. Board of Topographical Engs. arenow engagsd in making daily reports upon ths temperature of the atmosphers, position of the baror eter, and direction of air currents, stc., throughout ths United States. The ahove work has thus far heen mors or less limited in its scops and ussfulness, having hesn confined moatly to the territory of the United States and ths seas, gulfs and oceans which surround thsm. But now ws hear of another snd still grander project, proposed hy Lieut. Maury, for noticing ths forces at work on the entirs face of the glohs, and distrihuting the information ohtsined for the hsnefit of producers snd mankind in genersl. Hs proposes, with the aid and co-operation of ths yarious Governments of the world, and ths uss of all ths appliancs of stesm and electricity, to estahlish a vsst system of weather and crop ohssrvations and reports, which shall keep producers in all lands informed of whst is going on all over ths glohe, so that thsy may know wherewith thsy'are competing and what their prospects are in the market. “Tn this age of steam and rapid communication” remsrks a cotsmporsry, ‘‘the graingrowsr of Tlinois is a competitor of the grsin-growsr of the Danuhe, and ths cotton-plsnter of Georgia must measuys ths vslus of his crop hy the products of the fields of India and Egypt. That this measure may hs accurately mads as the seasons advance, Prof. Maury has projscted the scheme referred to. He helieves that mau hss already in his hands powers and agencies which will enahls the grain-grower of ths West and ths cotton-planter of the South to know, as ths season progresses, the prohahle supply of the stapls in which he is intsrested in all quarters of ths globs, and when the times of harvest come in ths different climes, to hs informed with approximate precision of actual quantitiss sent into the market. The henefits of tho scheme are apparent; its practicability is no more donhtful than of many other great undertakings which have heen carried through to success seemed to he when they were first projected.” Frost Work Imitated, Among the curiosities of recent scientific discovery, may he instanced that made hy M. Bertsch, and turned to practical account hy M. Kuhlmann, ths celehrated chemist. M. Bertsch has found that Epsom salts, or sulphate of magnesia, dissolved in heer, together with a amall quantity of dextrine, or artificial gum, applied toa pane of glass with a hrush, will, on crystallizing, produce the identical designs formed on the glass hy frost in cold weather, with this improvement, that the liquid may receive any color whatever, at the option of the operator. M. Kuhlmann, however, conceived the idea of going a step further, and transferring those fairylike creations to stuffs and papers. By means of a powerful hydraulic press, the minutest details of the figures in qnestion were duly imprinted on the soft metal, and a cony of them in relief was then ohtained hy galvanoplastics. But in the impression of cotton stuffs, the patterns mnst ho continuous, whereas in M. Kuhlmann’s plates the lines at one end would fail to coincide with those at the other, cansing disagreeahle interruption in the printed designs. To overcome this, he ingeniously effected the crystallization of the cylindrical snrface of aroller. A slight rotary motion imparted to it, prevents the liquid from accnmulating at any particular point hefors it is evaporated. Srinver stains may he removed hy hleaching with chloride of copper, and then washed ont with hyposulphite of soda, and afterwards with water. aa -