Volume 24 (1872) (424 pages)

Jnue 2g, 1872.) SGIENTIF LCs PRESS. 403 [ee Ss GCIENTIFIC Proaress. Dr, Carpenter's Theory of Ocean Currents. Dr. W. B. Carpsnter presente in the Popular Science Review a very interesting resume of the resnita of his deep-sea investigations. In his first expsdition to the deep channel between the shetland aud Faroe Islands, at the depth of 600 fathome in ons place ths self-registcring thermometer indicated o tempcratars of 45 to 43 degrees Fahri; whilo at another part of the channel, only twenty miles away, atemperaturo of 32 degrecs at the bottom was recorded—a vory marked and curious contrast. The next year most remarkable contrasts of bottom temporature were shown at differant depths on ths southern slops of tho samo channel. At a depth of 190 fathome, the temperature was 48 degrees, while only eight miles uorth where the depth increased to 445 fathome, the thermometer sank to 30 deg.—thus showing a difference of deep-sea temperature of 20 degrees within that short descent of only 225 fathoms in depth. At both places the surfaco temperature was 52 degrses. Further where ths surface tamperaturo was bstween 49 and 50 degrece, serial ph indicated at 350 fathoms a temperature of 32 degrees, that of freezing water; and from that point to the bottom, 640 fathoms a river of glacial water waa found, below the freezing point of fresh water, in one of his more recent expeditions off the eoast of Spain and Portugal, where the surface temperature of the water wus as high as 65 degress, serialsoundings indicated a loss of ouly 10 degrees for the first 100 fathoms; which, therefore, may be termed the superheated surface, nnder the powerful rays of a midsummer sun. Then, down to 300 fathoms, the temperature lowered very slowly only to 49 fathoms, showing a warm stratum of water. But in the next 200 fathoms there wasa descent to 40 degreee; and from this level of 1,000 fathoms to the bottom, at 2,435 fathome or nearly 3 miles—a depth about equal to the hight of Mt, Blanc—the temperature stcadily lowered to 36.5 degreee and still lower resulte were obtained near the equator. Here then was a lower stratum of very cold cold water of no less than 1,400 fathoms in thickness. Commander Chimneo found olose to the Eqnator, 3 degrees S. latitude, a bottom temperature at 1,800 fathoma of 35 degrees, and at 2,306 fathoms one of 33.6 degrees. Whence comes this deep layer of nearly freezing water, and how does it retain its low temerature? As the water above it and the earth elow it are warmer, it could not long retain its temperature if stationary, unless continually snpplied from some constant eource of glacial cold. That it possessee the movement of a running stream is shown hy the nature of the bottom, the pebhles there being ronndedinstead of angular; and that it comee from the polar regions, is proved hy the fact that itmay be traced to them in its slightly decreaeing temperature. To the westward of the Faroe banks is a steep slope, going down 2,000 fathoms; from here to Labrador and Greenland ie a wide channel, through which a large mass of ice-cold water may pass into the great Atlantic hasin. But water cannot be alwaye flowing out of the polar regione without water from eome other source constantly flowing in toward it; so thst, if there is sueh an outflow helow, the circulation must be completed hy a coustant inflow at the surface above. This Dr. Carpenter findsinthe Gulf Stream, ond the universal movement of heated water from the equatorial to the polar seas.— The Weel. Srontaxgous Exp ostons.—F. Moigno says: —When finely pulverized chlorate of potash ie put on a piece of paper (best dredged or dusted over it, so as to form a thin film of powder), and there ienext poured over it a solution of phosphorus in bisnlphide of carbon, there enenes, when the latter is evaporated suddenly, a most violent explosion, owing to the phosphorus being left in a state of extremely minute division and in intimate contact with chlorate of potash. Thie explosion is analogous to that which ensnes when a small piece of phosphorus and some chlorate of potash are, when placed upon an anvil, struck with a hammer, ut, in the instance alluded to, the effect produced is greater, owing to the extreme state of division and intimate mixture of the two suhetances. Care should be taken not to make this experiment with too large quantities of the chlorate and phosphorus solution, for fear of serious accidents which might ensue. ABsonBING SuLPAUROUS Fomxs.—M. Cahen, the author euggests for thie purpose the nse of peroxide of manganese of low quality; The absorption of sulphnrons acid gas, included that evolved in metallurgical operations, is instantaneous; and if the ensuing manganese salts do not happen to he commercially of use they can be readily, by means of chloride of sodinm, converted into hyposulphite of soda and other soda, salts. Tue annual cost of maintenance of the galvanic hatteriee used by the Weetern Union Telegraph Co., is over $125,000. Gas Burners for Bending Glass Tubes. The American Chemist for January contains a note by Prof. J. Lawrenee Smith, ‘On Banding Glass Tubes for Fitting Apparatus,”’ in whieh hs reccommends a Bunsen burner flattened st ite extremity so as to gives athin broad flame. An ordinary fishtwil or batwing gasburner will bs fonnd to give, if possible, still better resulte. Mr. Al. Carrington Bolton writes that he has employed for some years au ordinary batwing burner attached to a small, short stand (thres inchee high, burner inelnded), eo a8 to rest low upon tho table, in order that raiyiug the arms inconveniently high may bs avoided. Such a burner insures u broad flame, by which ths tube is heated for two or more inches in length, the tube is turned while in the flame, and removed for bending se usual, the deposit of carhon which at tirst sight might seem an objection is really one of the chief advantages of nsingthis hurner. On placing the glassin ths flame the deposit begins imniediately, and prevents too rapid a rise of temeal and consequent cracking of the glass; uring the heating the carbon tends to distribute the heat eqnally over the surface of tho tube; and finally, on withdrawing ths glass from the flame, too sudden cooling is prevented, aud the glass is, as it were, annealed. Ths black deposit is rendily removed by a dry cloth, This plan wascommonly smployed in Homann’s Laboratory, Berlin. In bsuding tubee of more than three-sighths of an inch in diameter one end should be cloeed tightly with a cork (or wax), and air blown into the other end at the moment of bending the tube; by regulating judiciously the pressure of the air upon the sides of the somewhat softened tube, the latter will neither bulge out nor collapse, bnt will retain its proper caliber. This cannot be effected, however, with very large tnhes, or with very thin ones, which require the nice manipulation of the professional glass-blower. —Am. Artisan. Faviry Vision in Patnrers.—Considerable attention has been attracted by a lecture delivered hy Dr. R. Liebrich on this snhject at the London Institution. The lecturer referred particularly tothe case of Turner, hetween whose carlier and whoee Jater paintings a marked difference appears. The prominent feature of the change consists of a vertical streakiness, each luminons point being changed into a vertical line. Now it iecommonly eupposed that Turner adopted a pecnliar manner and exaggerated it more and more. The fact, accordiug to Dr. Liebrich, appears to he that the change of manner arose from a change in his eyes, a growing dimness of the crystalline lens causing himto see hoth nature and his own pictnres incorrectly. The gradual change was traced hy the lecturer, and its effects illnstrated by the use of lene and of picturee projected on a screen. Other caees arising from irregularities of re~ fraction in the eye were epoken of. It may occur that an eye is normal in one direction and ahnormal in another, and hence dietorted pictures are produced, eo there are affections of the eye in regard to color. Somo of Turner’s admirers have come to the vindication of their favorite, and have been trying to disprove the doctor’s reasoning. Naropa SELEcTIon Iv PLANTs.—An attempt is made by Dr. Chauncey Wright, in the Memoirs Amer. Academy, to explain on the principal of natural eelection the existence of the modes of phyllotaxis most frequently foundin Nature. These consist of two principal forms, the verticillate and the spiral, of which the latter is by far the most general and most complicated. By an elahorate series of circulations he shows that the particular forms of spiral arrangement actually found in Nature are those which possess the greatest advantage for the plant, hy soarranging the leaves, and, thercfore, branches, that they have the most perfect distribution for notintsrfering with one another, both.in drawing nutriment from the etem and in exposure to the light. To Protect Iron anp STEEL.—Prof. F. Grace Calvert, of England, has diecovered that the carhonates of potash and soda possees the same . , property of protecting iron and steel from rnst as do those alkalies in a caustic state. If an iron hlade is half immersed in a solution of either of the above named carhonates, it exerts so protective an action that that portion of the iron which is exposed to the intiuence of the damp atmoepheric air doee not oxidize, even after a period of two years. Similar reeults have been obtained with sea water, to which have heen added the carbonates . of potash orsoda. The applications of this fact are numerous and important. AtMoerHERIC THERMAL Parapox.—The higher we ascend, the colder it hecomes; and yet at very great elevations the raye of the sun exert aheating power greater than that which they are found to produce in the valleys. Prof. Piazza Smyth found, that on the top of Teneriffe, at an elevation 10,000 feet above the level of the sea, a thermometer exposed to the direct trays Of the sun, ehowed 4 temperature of nearly 200° deg. Fah !—Prof. Phin. Tue conversion of water into vapor develops electricity .the main line. y~ MECHANICAL Procress A New Metruonoy Determixino tae QuaLity or Inox.—Mr. VsuRuth, Inspector of Mines for the Dutch government, has devised a method of printing from iron in snch a manner as to show its fibre, and give a correct picture of the same for comparison or reference. The sample of iron whoss fibre, is to bs examined is first planed, so as to expose a suitable‘ ssction, throngh any desired point; this section is im. mersed in muriatic (hydrochloric) acid for such time as is neccessary to eat ont the cinder; this time varies from six hours to twenty-fonr honrs according to ths strength and temperature of the neid solution. The einder is attacked in a more rapid nianner than the fibre of tho iron, and tho sffeet is that the fibrs is left in relief— in fact, an etched plate is formed, from which, by euitable ink or other substances, an engraying may be printed, showing every fibre of tho iron in clear and distinct manner. Ths application of this simple process is too obvious to nsed much description. Whenevsr ths formation of piles in a rail, round or other aection of iron is reqnirsd, here is a quick and handy method for discovering it. As a means of studying the alteration of fibre in the neighborhood of welds, itis invaluable. It may also be applied in snpplying information in relation to Mr. Tresca's valuable memoireon ths flow of eolids. Tue Pro Switcn has heen adopted as the etandard by the Western Union Telegraph Co. The diagram shows ite connections as adapted to the requirements of a way office. It is eo simple, and yet eo perfect, that only a very hrief explanation of the reference marke npon thediagram will be necessary to a full understanding. lrepreeente a vertical metallio bar or strip npon the ewitch, to which ie connected a wire running into an office, and 2 repeesente the ename wire going ont. A and A’ and Band B’ are metallic huttons, to which are connected the instrument wires. All the hnttons upon the same horizontal line aré conuested together at the hack of the ewitch. As shown in the ent, the cirent ie “open.” To close it, with instrument in circuit, it wonld he neceesaray only to insert two metal plunge or pegs; one at the orifice at B’ and 2, and one atAand 1. The courseof the current would then be as follows:—From the line at 1 throngh the peg connection at A to instrument; through inetrument to B and B’; through the peg connection there to the line at 2, and so out to the mnnin line, Should it he desired to connect the line through, withont instrument in circuit, the insertion of pegs in the orifice of either A* or B’ would effect the desired result. The same form of switch, with a modification of connections, would answer for a terminal office. For this, let it be nnderstvod, that a wire, leading from a hattery, one pole of which is grounded, is taken directly to one side of the instrument; through the instrument it goes to A; from A, if a peg he inserted in its orifice, itgoes to 1 and to If, instsad of placing the peg at A and 1, itbe placed at A’ and 2, the instrument would he connected to line 2. It will be eeen that in the terminal form but one line wire is necessary to be on the ewitch, and but one wire tothe instrument to form a circuit, while in the way form two of each are required. Jour. Telegraph. Rarmzoap Tonrenors.—One of the neatest and most effective little arrangemente for safety in railroad operations is the ‘torpedo '’ or alarm signal, Thie little affair consists of a tin hox ahout the size and shape of the smallestsized blacking-boxee. The box is filled with an explosive componnd, and two strips of tin are soldered to two opposite sidee of the hox perpendicular to its sidee or edges, for fastening it to the rail. These hoxes explode on the principle of the percussion-cap, with a lond report. They are in uee on some roads for night signals and in foggy weather, when lights or flags would not he seen in time to prevent accident. Track-men are provided with these torpedoss, and in case of danger they are placcd on the rail, far enough from the place of danger to prevent disaster. Usually three of them are placed a few feet apart, to insure their being heard hy the engineer. They are reliable, and will explode at the touch of the wheel at the slowest speed. They cost hut a trifle. Itis said that the Reading company uses 35,000 of the torpedoes per annum on the roade which it operates.— Railroad Gazette, Road Steamers—Rubber Tires. The use of steam on common roads has made great strides daring the past year, and it is but fair to Mr. Thompson, of Edinburgh, to state that much of this progross is due to him, Let what will be said on the subject of indiarubber tires, it is day by day becoming mors evident that an elastic wheel of some kind is eesential to ths full euceees of ths tractlon engine or road locomotive. One of the great objections to its use hitherto urged against it has heen sxtremsly slowspeed at which alone it could travel, A nominal velocity of 4 milee an hour really meaus, when all deductions are made for the delayaineurred by stopping for horsee, taking in water, etc., a rats of.uot more than two miles an hour. This does not tsll heavily in one ssnse against loaded engince, but it greatly increases tho cost of working them, in that, in returning light for a sceond load, ths duration of a trip is unneceesarily prolonged. A traction engins, to bs rendily efficient, should be competent to travel, when it geta a chance, at six miles an honr; more is nnnecessary for ordinary work. This speed cannot be obtained without springs of some sort. It is however, vary inconvenient to apply eprings in the ordinary way to the driving wheels, for reasons too obvious to all builders of such mnachines to require comment; and it must fnrther be remembered that, even if thie were not the case, the duties of a epring are but half performed when the spring is located between the engine and the axle. A six feet wheel of sufiicient breadth, to be strong enongh, will weigh about 18 cwt., in some cases as much as 22 cwt. It is not too much to say that the dead weight, unaffected by the use of springs, will therefore amount in a 12-horse power traction engine to rather more than two tons, which is highly objectionahle. The only way out of the difficulty Jies in placing the spring at or in the tire of the wheel, and the snecess which has attended Mr. Thompson in hie lahors is due to’ the fact, that his india tubher tire exactly complies with this condition. The great ohjection to the india-rubher liesin its enormous cost—over $500 for a moderate sized engine—and the nneertainty of the material. Thus the Ravee on her wonderfnl trip from Ipswich to Edinhurgh and hack, rendered one leading tire nseless on her journey to the north, and ehe disabled another on her journey to the south. As the tiree cost about $250 each, we have an ontlay of ahont $500 for a journey of 900 mitee, or a cost of 67 cts per mile for tires alone, The ruin of the tire in this case wae no donht, mainly dne to the heating of the mbher caused by the high epeed mainteined.—Engineer. Renvucino SteaM-Powen.—It is mneh more economical to reduce power below that which the boiler and engine can give, than to do ths reverse, and to drive the boilere and engine above their fair capacity, not to speak of the danger involved. There are eeveral ways of saving fuel by reduction of power; one is simply to economize hy carrying less pressure in the boiler; another to carry the same preesure, hut to aave steam hy some cnt-off arrangement; a third hy changing the size of the main pulley, so as to keep up the same velocity of the maehinery while the engine runs at a lesser velocity. Which of these methods is the most economical is difficult tosay. It depends on Many circumstances, as for alinost every engine there is a peculiar rate of.velocity, steam-pressure, ete., at which it runs to the best advantage, Manufacturer and Builder, Czxsium.—Few sources of the rare metal cessium have recently heen discovered, which somewhat extend the range of ite distrihution. Tt has lately been detected in the water of the hot spring of Wheal Clifford, England, hy Col. Yorke, who finds 1.7 parts of the chloride of emsium inone million parts of the water, making the latter ten times richerin this metal than that of the Durkheim spring, in which it was originally discovered hy Bunsen, Professor Miller had previously fonnd a considerahle amonnt of lithium in the water of this spring. From an examination of heryl from the Island of Elha, E. Becchi announces in the Eahrbuch fur Mineralogie the obtaining 0.80 per cent. of cesia. Elha is the locality of pollux, the mincral which contains the greateet percentage of this metal, Quicx Worx.—The Cabot Co., of Brunswick, in order to enlarge their cotton mill, latsly moved their large smoke stack chimney—78 ft. high, 7 ft. 9 in. equare at hase and 5 ft. square at top, containing over 40,000 hricks and weighing over 100 tons—twenty feet without rollers, halls, guys or hraces to steady it. Not one of those engaged had ever witnessed the moving of such a hody. It was accomplished by building such ways as are used in lannching ships; surfaces planed and greased, chimney wedged np aud moved hy two jack-screws in 4% hours. The flues were disconnected from the hoiler at 1 P. m., and at 9% the same evening the flnes were again connected, fires going and eteam np.—ZIndustrial Monthly.

Jnue 2g, 1872.) SGIENTIF LCs PRESS. 403 [ee Ss GCIENTIFIC Proaress. Dr, Carpenter's Theory of Ocean Currents. Dr. W. B. Carpsnter presente in the Popular Science Review a very interesting resume of the resnita of his deep-sea investigations. In his first expsdition to the deep channel between the shetland aud Faroe Islands, at the depth of 600 fathome in ons place ths self-registcring thermometer indicated o tempcratars of 45 to 43 degrees Fahri; whilo at another part of the channel, only twenty miles away, atemperaturo of 32 degrecs at the bottom was recorded—a vory marked and curious contrast. The next year most remarkable contrasts of bottom temporature were shown at differant depths on ths southern slops of tho samo channel. At a depth of 190 fathome, the temperature was 48 degrees, while only eight miles uorth where the depth increased to 445 fathome, the thermometer sank to 30 deg.—thus showing a difference of deep-sea temperature of 20 degrees within that short descent of only 225 fathoms in depth. At both places the surfaco temperature was 52 degrses. Further where ths surface tamperaturo was bstween 49 and 50 degrece, serial ph indicated at 350 fathoms a temperature of 32 degrees, that of freezing water; and from that point to the bottom, 640 fathoms a river of glacial water waa found, below the freezing point of fresh water, in one of his more recent expeditions off the eoast of Spain and Portugal, where the surface temperature of the water wus as high as 65 degress, serialsoundings indicated a loss of ouly 10 degrees for the first 100 fathoms; which, therefore, may be termed the superheated surface, nnder the powerful rays of a midsummer sun. Then, down to 300 fathoms, the temperature lowered very slowly only to 49 fathoms, showing a warm stratum of water. But in the next 200 fathoms there wasa descent to 40 degreee; and from this level of 1,000 fathoms to the bottom, at 2,435 fathome or nearly 3 miles—a depth about equal to the hight of Mt, Blanc—the temperature stcadily lowered to 36.5 degreee and still lower resulte were obtained near the equator. Here then was a lower stratum of very cold cold water of no less than 1,400 fathoms in thickness. Commander Chimneo found olose to the Eqnator, 3 degrees S. latitude, a bottom temperature at 1,800 fathoma of 35 degrees, and at 2,306 fathoms one of 33.6 degrees. Whence comes this deep layer of nearly freezing water, and how does it retain its low temerature? As the water above it and the earth elow it are warmer, it could not long retain its temperature if stationary, unless continually snpplied from some constant eource of glacial cold. That it possessee the movement of a running stream is shown hy the nature of the bottom, the pebhles there being ronndedinstead of angular; and that it comee from the polar regions, is proved hy the fact that itmay be traced to them in its slightly decreaeing temperature. To the westward of the Faroe banks is a steep slope, going down 2,000 fathoms; from here to Labrador and Greenland ie a wide channel, through which a large mass of ice-cold water may pass into the great Atlantic hasin. But water cannot be alwaye flowing out of the polar regione without water from eome other source constantly flowing in toward it; so thst, if there is sueh an outflow helow, the circulation must be completed hy a coustant inflow at the surface above. This Dr. Carpenter findsinthe Gulf Stream, ond the universal movement of heated water from the equatorial to the polar seas.— The Weel. Srontaxgous Exp ostons.—F. Moigno says: —When finely pulverized chlorate of potash ie put on a piece of paper (best dredged or dusted over it, so as to form a thin film of powder), and there ienext poured over it a solution of phosphorus in bisnlphide of carbon, there enenes, when the latter is evaporated suddenly, a most violent explosion, owing to the phosphorus being left in a state of extremely minute division and in intimate contact with chlorate of potash. Thie explosion is analogous to that which ensnes when a small piece of phosphorus and some chlorate of potash are, when placed upon an anvil, struck with a hammer, ut, in the instance alluded to, the effect produced is greater, owing to the extreme state of division and intimate mixture of the two suhetances. Care should be taken not to make this experiment with too large quantities of the chlorate and phosphorus solution, for fear of serious accidents which might ensue. ABsonBING SuLPAUROUS Fomxs.—M. Cahen, the author euggests for thie purpose the nse of peroxide of manganese of low quality; The absorption of sulphnrons acid gas, included that evolved in metallurgical operations, is instantaneous; and if the ensuing manganese salts do not happen to he commercially of use they can be readily, by means of chloride of sodinm, converted into hyposulphite of soda and other soda, salts. Tue annual cost of maintenance of the galvanic hatteriee used by the Weetern Union Telegraph Co., is over $125,000. Gas Burners for Bending Glass Tubes. The American Chemist for January contains a note by Prof. J. Lawrenee Smith, ‘On Banding Glass Tubes for Fitting Apparatus,”’ in whieh hs reccommends a Bunsen burner flattened st ite extremity so as to gives athin broad flame. An ordinary fishtwil or batwing gasburner will bs fonnd to give, if possible, still better resulte. Mr. Al. Carrington Bolton writes that he has employed for some years au ordinary batwing burner attached to a small, short stand (thres inchee high, burner inelnded), eo a8 to rest low upon tho table, in order that raiyiug the arms inconveniently high may bs avoided. Such a burner insures u broad flame, by which ths tube is heated for two or more inches in length, the tube is turned while in the flame, and removed for bending se usual, the deposit of carhon which at tirst sight might seem an objection is really one of the chief advantages of nsingthis hurner. On placing the glassin ths flame the deposit begins imniediately, and prevents too rapid a rise of temeal and consequent cracking of the glass; uring the heating the carbon tends to distribute the heat eqnally over the surface of tho tube; and finally, on withdrawing ths glass from the flame, too sudden cooling is prevented, aud the glass is, as it were, annealed. Ths black deposit is rendily removed by a dry cloth, This plan wascommonly smployed in Homann’s Laboratory, Berlin. In bsuding tubee of more than three-sighths of an inch in diameter one end should be cloeed tightly with a cork (or wax), and air blown into the other end at the moment of bending the tube; by regulating judiciously the pressure of the air upon the sides of the somewhat softened tube, the latter will neither bulge out nor collapse, bnt will retain its proper caliber. This cannot be effected, however, with very large tnhes, or with very thin ones, which require the nice manipulation of the professional glass-blower. —Am. Artisan. Faviry Vision in Patnrers.—Considerable attention has been attracted by a lecture delivered hy Dr. R. Liebrich on this snhject at the London Institution. The lecturer referred particularly tothe case of Turner, hetween whose carlier and whoee Jater paintings a marked difference appears. The prominent feature of the change consists of a vertical streakiness, each luminons point being changed into a vertical line. Now it iecommonly eupposed that Turner adopted a pecnliar manner and exaggerated it more and more. The fact, accordiug to Dr. Liebrich, appears to he that the change of manner arose from a change in his eyes, a growing dimness of the crystalline lens causing himto see hoth nature and his own pictnres incorrectly. The gradual change was traced hy the lecturer, and its effects illnstrated by the use of lene and of picturee projected on a screen. Other caees arising from irregularities of re~ fraction in the eye were epoken of. It may occur that an eye is normal in one direction and ahnormal in another, and hence dietorted pictures are produced, eo there are affections of the eye in regard to color. Somo of Turner’s admirers have come to the vindication of their favorite, and have been trying to disprove the doctor’s reasoning. Naropa SELEcTIon Iv PLANTs.—An attempt is made by Dr. Chauncey Wright, in the Memoirs Amer. Academy, to explain on the principal of natural eelection the existence of the modes of phyllotaxis most frequently foundin Nature. These consist of two principal forms, the verticillate and the spiral, of which the latter is by far the most general and most complicated. By an elahorate series of circulations he shows that the particular forms of spiral arrangement actually found in Nature are those which possess the greatest advantage for the plant, hy soarranging the leaves, and, thercfore, branches, that they have the most perfect distribution for notintsrfering with one another, both.in drawing nutriment from the etem and in exposure to the light. To Protect Iron anp STEEL.—Prof. F. Grace Calvert, of England, has diecovered that the carhonates of potash and soda possees the same . , property of protecting iron and steel from rnst as do those alkalies in a caustic state. If an iron hlade is half immersed in a solution of either of the above named carhonates, it exerts so protective an action that that portion of the iron which is exposed to the intiuence of the damp atmoepheric air doee not oxidize, even after a period of two years. Similar reeults have been obtained with sea water, to which have heen added the carbonates . of potash orsoda. The applications of this fact are numerous and important. AtMoerHERIC THERMAL Parapox.—The higher we ascend, the colder it hecomes; and yet at very great elevations the raye of the sun exert aheating power greater than that which they are found to produce in the valleys. Prof.

Piazza Smyth found, that on the top of Teneriffe, at an elevation 10,000 feet above the level of the sea, a thermometer exposed to the direct trays Of the sun, ehowed 4 temperature of nearly 200° deg. Fah !—Prof. Phin. Tue conversion of water into vapor develops electricity .the main line. y~ MECHANICAL Procress A New Metruonoy Determixino tae QuaLity or Inox.—Mr. VsuRuth, Inspector of Mines for the Dutch government, has devised a method of printing from iron in snch a manner as to show its fibre, and give a correct picture of the same for comparison or reference. The sample of iron whoss fibre, is to bs examined is first planed, so as to expose a suitable‘ ssction, throngh any desired point; this section is im. mersed in muriatic (hydrochloric) acid for such time as is neccessary to eat ont the cinder; this time varies from six hours to twenty-fonr honrs according to ths strength and temperature of the neid solution. The einder is attacked in a more rapid nianner than the fibre of tho iron, and tho sffeet is that the fibrs is left in relief— in fact, an etched plate is formed, from which, by euitable ink or other substances, an engraying may be printed, showing every fibre of tho iron in clear and distinct manner. Ths application of this simple process is too obvious to nsed much description. Whenevsr ths formation of piles in a rail, round or other aection of iron is reqnirsd, here is a quick and handy method for discovering it. As a means of studying the alteration of fibre in the neighborhood of welds, itis invaluable. It may also be applied in snpplying information in relation to Mr. Tresca's valuable memoireon ths flow of eolids. Tue Pro Switcn has heen adopted as the etandard by the Western Union Telegraph Co. The diagram shows ite connections as adapted to the requirements of a way office. It is eo simple, and yet eo perfect, that only a very hrief explanation of the reference marke npon thediagram will be necessary to a full understanding. lrepreeente a vertical metallio bar or strip npon the ewitch, to which ie connected a wire running into an office, and 2 repeesente the ename wire going ont. A and A’ and Band B’ are metallic huttons, to which are connected the instrument wires. All the hnttons upon the same horizontal line aré conuested together at the hack of the ewitch. As shown in the ent, the cirent ie “open.” To close it, with instrument in circuit, it wonld he neceesaray only to insert two metal plunge or pegs; one at the orifice at B’ and 2, and one atAand 1. The courseof the current would then be as follows:—From the line at 1 throngh the peg connection at A to instrument; through inetrument to B and B’; through the peg connection there to the line at 2, and so out to the mnnin line, Should it he desired to connect the line through, withont instrument in circuit, the insertion of pegs in the orifice of either A* or B’ would effect the desired result. The same form of switch, with a modification of connections, would answer for a terminal office. For this, let it be nnderstvod, that a wire, leading from a hattery, one pole of which is grounded, is taken directly to one side of the instrument; through the instrument it goes to A; from A, if a peg he inserted in its orifice, itgoes to 1 and to If, instsad of placing the peg at A and 1, itbe placed at A’ and 2, the instrument would he connected to line 2. It will be eeen that in the terminal form but one line wire is necessary to be on the ewitch, and but one wire tothe instrument to form a circuit, while in the way form two of each are required. Jour. Telegraph. Rarmzoap Tonrenors.—One of the neatest and most effective little arrangemente for safety in railroad operations is the ‘torpedo '’ or alarm signal, Thie little affair consists of a tin hox ahout the size and shape of the smallestsized blacking-boxee. The box is filled with an explosive componnd, and two strips of tin are soldered to two opposite sidee of the hox perpendicular to its sidee or edges, for fastening it to the rail. These hoxes explode on the principle of the percussion-cap, with a lond report. They are in uee on some roads for night signals and in foggy weather, when lights or flags would not he seen in time to prevent accident. Track-men are provided with these torpedoss, and in case of danger they are placcd on the rail, far enough from the place of danger to prevent disaster. Usually three of them are placed a few feet apart, to insure their being heard hy the engineer. They are reliable, and will explode at the touch of the wheel at the slowest speed. They cost hut a trifle. Itis said that the Reading company uses 35,000 of the torpedoes per annum on the roade which it operates.— Railroad Gazette, Road Steamers—Rubber Tires. The use of steam on common roads has made great strides daring the past year, and it is but fair to Mr. Thompson, of Edinburgh, to state that much of this progross is due to him, Let what will be said on the subject of indiarubber tires, it is day by day becoming mors evident that an elastic wheel of some kind is eesential to ths full euceees of ths tractlon engine or road locomotive. One of the great objections to its use hitherto urged against it has heen sxtremsly slowspeed at which alone it could travel, A nominal velocity of 4 milee an hour really meaus, when all deductions are made for the delayaineurred by stopping for horsee, taking in water, etc., a rats of.uot more than two miles an hour. This does not tsll heavily in one ssnse against loaded engince, but it greatly increases tho cost of working them, in that, in returning light for a sceond load, ths duration of a trip is unneceesarily prolonged. A traction engins, to bs rendily efficient, should be competent to travel, when it geta a chance, at six miles an honr; more is nnnecessary for ordinary work. This speed cannot be obtained without springs of some sort. It is however, vary inconvenient to apply eprings in the ordinary way to the driving wheels, for reasons too obvious to all builders of such mnachines to require comment; and it must fnrther be remembered that, even if thie were not the case, the duties of a epring are but half performed when the spring is located between the engine and the axle. A six feet wheel of sufiicient breadth, to be strong enongh, will weigh about 18 cwt., in some cases as much as 22 cwt. It is not too much to say that the dead weight, unaffected by the use of springs, will therefore amount in a 12-horse power traction engine to rather more than two tons, which is highly objectionahle. The only way out of the difficulty Jies in placing the spring at or in the tire of the wheel, and the snecess which has attended Mr. Thompson in hie lahors is due to’ the fact, that his india tubher tire exactly complies with this condition. The great ohjection to the india-rubher liesin its enormous cost—over $500 for a moderate sized engine—and the nneertainty of the material. Thus the Ravee on her wonderfnl trip from Ipswich to Edinhurgh and hack, rendered one leading tire nseless on her journey to the north, and ehe disabled another on her journey to the south. As the tiree cost about $250 each, we have an ontlay of ahont $500 for a journey of 900 mitee, or a cost of 67 cts per mile for tires alone, The ruin of the tire in this case wae no donht, mainly dne to the heating of the mbher caused by the high epeed mainteined.—Engineer. Renvucino SteaM-Powen.—It is mneh more economical to reduce power below that which the boiler and engine can give, than to do ths reverse, and to drive the boilere and engine above their fair capacity, not to speak of the danger involved. There are eeveral ways of saving fuel by reduction of power; one is simply to economize hy carrying less pressure in the boiler; another to carry the same preesure, hut to aave steam hy some cnt-off arrangement; a third hy changing the size of the main pulley, so as to keep up the same velocity of the maehinery while the engine runs at a lesser velocity. Which of these methods is the most economical is difficult tosay. It depends on Many circumstances, as for alinost every engine there is a peculiar rate of.velocity, steam-pressure, ete., at which it runs to the best advantage, Manufacturer and Builder, Czxsium.—Few sources of the rare metal cessium have recently heen discovered, which somewhat extend the range of ite distrihution. Tt has lately been detected in the water of the hot spring of Wheal Clifford, England, hy Col. Yorke, who finds 1.7 parts of the chloride of emsium inone million parts of the water, making the latter ten times richerin this metal than that of the Durkheim spring, in which it was originally discovered hy Bunsen, Professor Miller had previously fonnd a considerahle amonnt of lithium in the water of this spring. From an examination of heryl from the Island of Elha, E. Becchi announces in the Eahrbuch fur Mineralogie the obtaining 0.80 per cent. of cesia. Elha is the locality of pollux, the mincral which contains the greateet percentage of this metal, Quicx Worx.—The Cabot Co., of Brunswick, in order to enlarge their cotton mill, latsly moved their large smoke stack chimney—78 ft. high, 7 ft. 9 in. equare at hase and 5 ft. square at top, containing over 40,000 hricks and weighing over 100 tons—twenty feet without rollers, halls, guys or hraces to steady it. Not one of those engaged had ever witnessed the moving of such a hody. It was accomplished by building such ways as are used in lannching ships; surfaces planed and greased, chimney wedged np aud moved hy two jack-screws in 4% hours. The flues were disconnected from the hoiler at 1 P. m., and at 9% the same evening the flnes were again connected, fires going and eteam np.—ZIndustrial Monthly.