Volume 35 (1877) (426 pages)

August 4, 1877.] LOEN TDNG= AbiDeSCLENGIFIC PRESS 67 od ~~ M ECHANICAL ?P ROGRESS. A New Form of Boiler. Hoiler-makers know that it is not easy to draft a form of steam boiler which will not show objectionable points, and when the need comes to increase capacity, all danger and dithculties increase in a geometrical ratio. We read in /ren that an English tirm hope to overcome the objections which ean bo brought against the old Lancashire and Cornish styles of boilers by introducing another design: It is formed principally by two parallel shells of comparatively small diameter, which are conuected by a large nuinber of short vertical tubes. These two principal shells are placcd one aboye the other, and again above the upper shell is conneeteil a small stoam-chest with two small pipe connections, ono at cach end. Tho employment of this form of elephant boiler wii two or niore shells andexternallytired, enables largo grate surface to be provided with smalj diameter of shell, thus proving extremely valuable for burning wood shavings, or any other light combustible, and, at the same time, enabling the boiler to carry a comparatively high q orking pressuro with safety, say from 30 to 100 pounds per squaro inch. The arraugoment of the double shell also provides that very little danger is likely to be inenrred from shortness of water, as in Cornish or Lancashire boilers. For in these latter boilers a fall a few inches below tho average water level will lay bare the crown of the tlnes, which are the plates most exposed to the fiereest heat of the fre, and therefore the wost likely to be burnt and to collapse. Inthe elephant boiler the avorage water level is at a hight of twothirds of the upper shell. The tire, also, is placed undorneath tbe lowest shell; then returns along the sides of that shell and then back again under the upper shell. The whole boiler must then be entirely empty before the plates nearest the fire are laid bare, and should the upper shell become entircly emptied the plates would not be exposed to sufficient heat to cause any serious apprehension of danger. This is a great point of safety, as many explosions are undoubtedly caused hy over-heated plates from shortness of water. A special and unique feature in this new boiler is an ingenious arrangement of dip tubes to promoto circulation, In every alternate short connecting pipe hetween the two shells a loose dip tube ie dropped within a few inches of the bottom plates of the lower shell. These tubes will determine the circulation downwarde through them from tho upper shell, and the up~ wards circulation of steam and hot water will ascend through the alternate short junction pipes without dip tubes. The circulation thus produced is most decided. A stream of the coldest water is brought down directly to the hottest plates over the fire, which are thns niuch protected fron: wear and tear, and one of the great evils in long cylindrical shell boilera, ize hogging,’ is, we should believe, entirely Re sented. e main shells of the boilers are rought ont beyond the brick setting by projecting manholes, which will prove very handy in cleaning out and iuspecting. A Monster Sugar-Pan. We use sugar machinery in this State and our mechanics make some of it. Both users and makers will be iuterested to read of the largest vacnnm pan ever made. ron says it was made hy James Duff & Sons, Greenock, and gives a long description. We take out a few points on dimensions: This ‘‘ giant” of the vacuum-pan tribe is about 13 feet in diameter at its widest part and a little over 14 feet in depth from the top flanging, or 11 feet from the boiling line. It is somewhat of the heart shape, presenting as it does, the form of an inverted irregular cone, contracted to a point at the apex and widening gradually and quickly towards the base, the lower part heing somewhat flattened. The body of the pan is built in three tiers, consisting of the bottom, the ‘‘crib” or centerpiece and bell-mouth respectively. The bottom is in one piece, while the ‘‘ crib” is composed of three large segmental copper plates, joined together in a curved circle by means of flanges at their side edges, and to the bell-mouth and bottom respectively, by means of flanges at their upper and lower edges. The bell-mouth or top-piece is then surmounted by a large tapering copper pipe or neck (called the “ swanneck”), by means of which tbe pan is connected to a Lars cast-iron condenser on a superJacent floor of the refinery building, the condenser being in turn connected at the back end (for it is set horizontally) by means of a large pipe, (called the ‘‘ vacuum pipe’) to two powerful exhausting air-pumps, placed in communication with the pan, the water of condensation being carried off from the condenser through the medium of a so-called “balance” or “atmospheric” pipe. Intermediate between the vacuum-pan and the condeneer, a large copper receptacle (called the ‘ tell-tale” or “eate”) depends from the under side of the neckpipe, for the purpose of catching aud retaining, till the close of the boiling operation, any liquor that may be carried over from the pan towards the condenser through violent ebullition, and which, if not so caught, would pass on to and through the coudenser and so be carried off with the water of condensation and lost. The contents of this vessel are indicated by means of « glass gange at the side and are drawn off in due course through the medium of a stop-cock at the bottom. The lower half of this monster sugar-kettle contains the heating media, which consist of no lees than 11 largo serpentine steam-worms, oa arranged and adapted to the curvature of the pan. These steam-worme are four and a half to tive inches bore and about 900 fect in combined leugth, giving a heating surface of 1,119 superticial fect or thereby. The gross contents of the pan, up to the hoiliug line, is 973 cubic feet, or about 6,080 imperial gallons. Tho worm displacement amounts to 111 eubie feet, thus leaving the net capacity of the pan 862 cubic feet or thercby, while the heating surface stands to the net capacity as 1.3to 1. It is caleulated to boil 40 tons of sugar when charged to the boiling line, the time oceupicd in the process boing from four to seven hours, as the quality of the liquor and other circumstances may vary; the product in marketable sugar from this quantity being from 47 to 50 tierces. The shape of the pan is highly favorable to quick boiling and rapid evapora and concentration of the syrups; while the heating, condensing and vacuum power are, in every sense, replete and in fino symmetry with the gigantic dimensions and enormous capacity of the vessel; and as for workmanship, it is a fine specimen of the coppersmith’s art. Procress or Wire Cannrs.—The advance which wire cables are making and the way in which they are being rapidly substituted for Topes, chains and belts, has been frequently noted in these columns, We have now a report of some important trials of steel wire-rope hawsers which have been lately made at Portsmouth Dockyard, the results being such as to astonish the operators as to the enormous tensile strength which had been impartod to the wire. Breed is not only entering largely into tho construction of our ships of war, but, their standing rigging and hawsers are being gradually made of the same light and durable material, and in a short time the London Times expects that the present unwieldly chain cables in use will be superseded by steel wire cables of moderate thickness and weight. The recent tests at Portsmouth were of various samples of steel wire hawsers for towing purposes, it having been found from the experience of the Valorous and other ships that a wire hawser possesses equal flexibility to the hest hempen rope, combined with less weight, superior handiness, and greater endurance, without any increase in the first cost. Official experiments at Portsmouth have also established the fact that the breaking strain of a steel hawser is more than three times that of arope hawser. Thus a9 in. ordinary hawser will break under a strain of 164 tons, and a 19 in. hawser under a strain of 72 tons, whereas Bullevant & Co’s 3in. steel hawser hroke at 18 tons, and tbeir 6 in. hawser at 80 tons. In the matter of weight the advantage is also clearly on the side of the steel, the 3 in. and Gin. wire hawsers weighing 7 Ibs. and 29 Ibs. per fathom, while the 9 fin. and 19 in, hempen hawsers weighed 19 lbs. and 84 lbs. per fathom. The samples operated upon were respectively of the circumference of 3, 4, 5 and 6in. The core of each was formed of tarred hemp, over which was twisted 6 strands, each strand being composed of 19 highly-tempered steel galvanized wires. The 3 in. hawser, which was formed of 15 gauge wire, broke at 224 tons; the 4 in. 14 gauge, at 353 tons; the 5 in., 12 gauge, at 573 tons; and the Gin. 10 gauge, at the enormous strain of 1003 tons. In every instance the strauds parted at the splicing, which were the only parts displaying any appreciable elongation under the tests. PROURESS OF THE Metric SysteM.—The Boston Society of Civil Engineers has the distinction of being the first organized professional body in the United States to make a ayatematic effort to secure the introduction of the metrival system of weights and measuree into general use in this country. The society appointed a committee, whose duty it was to open communication with the various learned societies and leading manufacturers throughout tbe country, and secure the favorable action of Congress upon a memorial fixing a date for the official adoption of the metrical system, by the potency of a combined appeal from these intuential sources. The report of this committee now before us, says the Polytechuic Review, after showing that the metrical eystem is steadily growing in favor in this country, states that 29 replies were received from eocieties which were addressed as above noted. Of these replies, 16 were favorable, 5 unfavorable and § undecided. On the unfavorable list, the American Academy of Arts and Sciences indefinitely postponed the matter by a vote of 10 to S, on the ground that ‘it would be a hardship to deprive the people of their preseut standards if they preferred to use them;” and the Franklin Institute rendered its decision in favor of the sweeping etatement ‘“‘that the objections to the attempt to adopt the meter as a standard unit of linear measure are overwhelming.” These two bodies are the moet prominent objectore, & a SCIENTIFIC ‘PROGRESS. Geometrical Chemistry. We gave at the time of its first appearanco a synopsis of a thoory of # geometrical chemistry as proposed by Prof. Henry Wurtz. We notice now by the /ron Age, tbat the faculty of the Stevens Institute of Technology have paid a graceful tribute to American proses in science, by conferring the honorary degree of Doctor of Philosophy upon Prof, Menry Wurtz, A. M., for original research, and especially for tho discoveries upon whicb he bases his remarkablo theory of geometrieal chemistry. As this is the first time the faculty have used the power to confer honorary degrees, and as the faculty, which includes such cminent scierftists as Morton, Thurston, Mayer, Leeds and Wood were wuauilmous in the opinion that Prof. Wurtz’s discoveries were of sutticient value to merit the highest honor in their gift, the compliment is one of which any man of science might be proud. Prof. Wurtz has discovered a great number of facts in relation to the mathematical relations of molecular volumes—facts which had previously becn entirely unsuspected as well as unknown, ‘Tho first poiut sought by Prof. Wurtz was a standard temperature of nature. This he very conclusively demonstrates to be the temperature of ice at the point of incipient . 7, fusion. This found, the first fact discovered was that the volume of all single chemical molecules with one exception, are expressed by quantities which have the relations of even cubes of whole numbers, The one exception is oxygen, the inolecular volume of which, deduced from a comparison of water with peroxide of hydrogen, is 5,184, or three times the cube of 12, Calculations made upon the immense number of density terminations, fails to show that oxygen ever changes this volume—or diameter, as it is perhaps more appropriately called. Another discovery is the fact that hydrogen is the most vaviable of all the elements. It is fouud that molecules which combine to form a new substance, tends to assume very nearly the same size. Again, the tendency to vary increases with the electro-positive nature of theelement. Later researches develop the fact that, iu many different series of compounds, the diameter of some one element or elements vary in different members of tbe series by four units. The significance and importance of these facts alone are enough to render Prof. Wurtz’s labors worthy of high honors. Matine amone Frsnes.—A writer in a Berlin contemporary contributes some details of his experiences in pike fishing, which tend to show that the idea commouly entertained that the removal of the male fish from a water about spawning time has less effect upon the stock than the capture of the females, is altogether erroneous. Four or five weeks before spawning commences the jack seek the neighborhood of the shore in gronps, and he has invariahly observed that each of these consists of one female accompanied by one or more male fish, and so continues, unless disturbed, till the breeding season is over. Asa rule a female of small size is accompanied by one male only; a medium sized mother-fish has two or three males, and a full sized one as many as four or five. The larger the mother-fish the smaller, asa rule, are her attendant squires, the weight of the former being generally about equal to that of all the males put together. If the males of a group be caught shortly before spawning time, the bereaved female does not mate again that season; in due time of course she deposits her roe, but it remains unfertilized, and so perishes. By removal of some of tbe dorsal scales from all the memhers of the group taken in a net, so as to render their identification easy, it was found that on replacing them in the water at considerable distances from each other, they invariably reunited in a very short space of time. Under no circumstances was the spawn of a female bereaved of her attendant males, impregnated by tbe milt of others in the same water, however numerous the latter might be. A New Series of Onsecrrves.—At the latest meeting of the S. F. Microscopical Society, a letter was presented from Charles A. Spencer, of Geneva, New York, which was received in answer to an enquiry about ‘‘ Spencer’s Objectives.’ Among other things Mr. Spencer writcs: “From notices in the London Microscopical Journal, the American Naturalist, the American Journal of Microscopy, the Cincinnati Medical Neus, etc., it is quite evident that your Microscopical Society is alive one, and a gratifying fact it is to all devotees of science. I would give a cordial expression to the hope that its future progress may fulfill its present promise of being an honor to us all.” In answer to an enquiry, Mr. Spencer gave a description of a new eeries of objectives he was working up, in which he has it ag a special aim to produce ‘‘a series of objectives of quite moderate prices, yet of a high grade of excellence and of such almost absolute uniformity of quality thatthepurchaserneed have no fear of disappointment in this respect.” It is probable that the Society will have the opportunity of testing Mr. Spencer's new work. He is among the foremost of the optical instrument makers of this country; haviug made the telescope with which Professor C. H. F, Peters, of Hamilton College observatory, has discovered more asteroids than any other single observer, and a microscope for the late Professor Agassiz. Pitury—A New Stimulant. We learn from Nature, that Baron Von Mueller in a recent letter to the stustralian Medical Journal describes the origin of tbe Pitury, a stimulant said to be of marvellous power, and known to be in use by the aborigines of Central Australia. After years of efforts to get a speeimen of the plant, he had obtained leaves, but neither flowers nor fruits. He can almost with certainty, after due microscopic examination, pronounce those of the Pitury as derived from his Dubotsia Hopwoodti, described in 186) (Fraqm, Phytogr, Austr., [1,, 138). This bush extends from the Darling river and Barcoo to West Australia, through desert scrubs, but is of exceedingly sparse occurrence auywhere. In fixiny the origin of tho Pitury, a wide field for further inquiry is opened up, inasmuch as a second species of Duboixia (D, myoporoides RF. Br.) extends in forest land from near Sydney to near Cape York, and is traced »lso to New Caledonia, and latcly by him also to New Guinea. In all probability this D. myoporoides shares the properties of D. fHopwoodii, as he finds that both have the same burning acrid taste. Baron Mueller adds; ‘*Though the first known species is so near to us, we never suspected any such extraordinary properties in it as arc now established for the later discovered vo Moreover, the numerous species of the allied genus Anthocercis, extending over the greater part of the Australian continent and to ‘asmania, should now also be tasted, and further the many likewiso cognate Schwenkeas of South America should be drawn into the same cyclus of research, nothing whatever of the properties of any of these plants being known, The natives of Central Anstralia chew the leaves of Duboisia Hopiwoodéi, just as the Peruvians and Chilians masticate the leaves of the coca (Lrythroxylon coca), to invigorate themselves during their long foot journeys through the deserts. Iam not certain whether the aborigines of all districts iu which the Pitury grows are really aware of its stimulating power. Those living near tbe Barcoo travel many days’ journey to obtain this, to them, precious foliage, which is carried always about by them broken into small fragments aud tied np in little bags. It is not improbable that a new and perhaps important medicinal plant is thus gained. The blacks use the Duboisia to excite’ their courage in warfare—a large dose infuriates them.” No Bones in tHe OceAn.—Mr, Jeffrey has establisbed tbe fact that bones disappear in the ocean, By dredging, it is common to bring up teeth, but rarely ever a bone of any kind; these, however compact, dissolve if exposed to the action of the water but a little time. On the contrary, teeth—which are not bones any more than whales are fish—resist the destroying action of sea-water indefinitely. It is, therefore, a powerful solvent. Still, the popular opinion is that it is a briue. If such were tbe case,the bottom of all seas would, long ago, have been shallowed by immense accumulatiou of carcasses and products of the vegetable kingdom, constantly floating into them. Deutine, the pecnliar material of which teeth are formed, and the enamel covering them, offer extraordinary resistance to these chemical agencies, which resolve otber animal remains into nothingness, Mounds in the West, tumuli in Europe and Asia, which are believed to antedate sacred history for thousands of years, yield up perfectly sound teeth, on which time appears to have made no impression whatever. Mexico.—We are pleased to receive asample of what our sister repuhlic of Mexico is doing in the way of increasing knowledge of her development and_ resources of different kinds. Last February there was issued the first number of an official periodical entitled ‘‘Anales del Ministerio de Fomento.” This branch of the government has cognizance of all internal improvements, both of public aud private expeuse, and all scientific exploration to ascertain the topography, geography and various resources of the different Mexican States, The publicatiou of information of this valuable nature under the approval of the government, carries assurance of its accuracy and trustworthiness, and will be hailed with pleasure by many who are waiting for more knowledge of the Mexican republic; believing that the country is indeed a cornucopia in nature as well as form, The first numbers of the ‘‘Anales” show that the work of making the country known to her own citizene and foreigners is to be done scientifically and creditably. Our acknowledgements are due to the Hou. Riva Palacio for copies of the ‘fAnales.” Giant Powprr in Arctic EXpLoratrions,— The accounts of the English Arctic expedition under Capt. Nares, show the application of many devices supplied by tbe advancement of science in overcoming the many obstacles presented by nature to guard the approach to the pole. Electricity made day of the five months of night, while dynamite opened the way throngh heretofore unsurpassable ice barriere. Cartridges of dynamite were eimply placed upon the surface of the ice and their explosion was eufficient to cleat a passage. Where large masses of ice were encountered, miues were dug, the cartridges placed therein, and the passage choked up with ice blocks so as to increase the effect of the exploeion. By simultaneously exploding of a number of these mines, open tracts for the passage of the vessels were easily obtained.

August 4, 1877.] LOEN TDNG= AbiDeSCLENGIFIC PRESS 67 od ~~ M ECHANICAL ?P ROGRESS. A New Form of Boiler. Hoiler-makers know that it is not easy to draft a form of steam boiler which will not show objectionable points, and when the need comes to increase capacity, all danger and dithculties increase in a geometrical ratio. We read in /ren that an English tirm hope to overcome the objections which ean bo brought against the old Lancashire and Cornish styles of boilers by introducing another design: It is formed principally by two parallel shells of comparatively small diameter, which are conuected by a large nuinber of short vertical tubes. These two principal shells are placcd one aboye the other, and again above the upper shell is conneeteil a small stoam-chest with two small pipe connections, ono at cach end. Tho employment of this form of elephant boiler wii two or niore shells andexternallytired, enables largo grate surface to be provided with smalj diameter of shell, thus proving extremely valuable for burning wood shavings, or any other light combustible, and, at the same time, enabling the boiler to carry a comparatively high q orking pressuro with safety, say from 30 to 100 pounds per squaro inch. The arraugoment of the double shell also provides that very little danger is likely to be inenrred from shortness of water, as in Cornish or Lancashire boilers. For in these latter boilers a fall a few inches below tho average water level will lay bare the crown of the tlnes, which are the plates most exposed to the fiereest heat of the fre, and therefore the wost likely to be burnt and to collapse. Inthe elephant boiler the avorage water level is at a hight of twothirds of the upper shell. The tire, also, is placed undorneath tbe lowest shell; then returns along the sides of that shell and then back again under the upper shell. The whole boiler must then be entirely empty before the plates nearest the fire are laid bare, and should the upper shell become entircly emptied the plates would not be exposed to sufficient heat to cause any serious apprehension of danger. This is a great point of safety, as many explosions are undoubtedly caused hy over-heated plates from shortness of water. A special and unique feature in this new boiler is an ingenious arrangement of dip tubes to promoto circulation, In every alternate short connecting pipe hetween the two shells a loose dip tube ie dropped within a few inches of the bottom plates of the lower shell. These tubes will determine the circulation downwarde through them from tho upper shell, and the up~ wards circulation of steam and hot water will ascend through the alternate short junction pipes without dip tubes. The circulation thus produced is most decided. A stream of the coldest water is brought down directly to the hottest plates over the fire, which are thns niuch protected fron: wear and tear, and one of the great evils in long cylindrical shell boilera, ize hogging,’ is, we should believe, entirely Re sented. e main shells of the boilers are rought ont beyond the brick setting by projecting manholes, which will prove very handy in cleaning out and iuspecting. A Monster Sugar-Pan. We use sugar machinery in this State and our mechanics make some of it. Both users and makers will be iuterested to read of the largest vacnnm pan ever made. ron says it was made hy James Duff & Sons, Greenock, and gives a long description. We take out a few points on dimensions: This ‘‘ giant” of the vacuum-pan tribe is about 13 feet in diameter at its widest part and a little over 14 feet in depth from the top flanging, or 11 feet from the boiling line. It is somewhat of the heart shape, presenting as it does, the form of an inverted irregular cone, contracted to a point at the apex and widening gradually and quickly towards the base, the lower part heing somewhat flattened. The body of the pan is built in three tiers, consisting of the bottom, the ‘‘crib” or centerpiece and bell-mouth respectively. The bottom is in one piece, while the ‘‘ crib” is composed of three large segmental copper plates, joined together in a curved circle by means of flanges at their side edges, and to the bell-mouth and bottom respectively, by means of flanges at their upper and lower edges. The bell-mouth or top-piece is then surmounted by a large tapering copper pipe or neck (called the “ swanneck”), by means of which tbe pan is connected to a Lars cast-iron condenser on a superJacent floor of the refinery building, the condenser being in turn connected at the back end (for it is set horizontally) by means of a large pipe, (called the ‘‘ vacuum pipe’) to two powerful exhausting air-pumps, placed in communication with the pan, the water of condensation being carried off from the condenser through the medium of a so-called “balance” or “atmospheric” pipe. Intermediate between the vacuum-pan and the condeneer, a large copper receptacle (called the ‘ tell-tale” or “eate”) depends from the under side of the neckpipe, for the purpose of catching aud retaining, till the close of the boiling operation, any liquor that may be carried over from the pan towards the condenser through violent ebullition, and which, if not so caught, would pass on to and through the coudenser and so be carried off with the water of condensation and lost. The contents of this vessel are indicated by means of « glass gange at the side and are drawn off in due course through the medium of a stop-cock at the bottom. The lower half of this monster sugar-kettle contains the heating media, which consist of no lees than 11 largo serpentine steam-worms, oa arranged and adapted to the curvature of the pan. These steam-worme are four and a half to tive inches bore and about 900 fect in combined leugth, giving a heating surface of 1,119 superticial fect or thereby. The gross contents of the pan, up to the hoiliug line, is 973 cubic feet, or about 6,080 imperial gallons. Tho worm displacement amounts to 111 eubie feet, thus leaving the net capacity of the pan 862 cubic feet or thercby, while the heating surface stands to the net capacity as 1.3to 1. It is caleulated to boil 40 tons of sugar when charged to the boiling line, the time oceupicd in the process boing from four to seven hours, as the quality of the liquor and other circumstances may vary; the product in marketable sugar from this quantity being from 47 to 50 tierces. The shape of the pan is highly favorable to quick boiling and rapid evapora and concentration of the syrups; while the heating, condensing and vacuum power are, in every sense, replete and in fino symmetry with the gigantic dimensions and enormous capacity of the vessel; and as for workmanship, it is a fine specimen of the coppersmith’s art. Procress or Wire Cannrs.—The advance which wire cables are making and the way in which they are being rapidly substituted for Topes, chains and belts, has been frequently noted in these columns, We have now a report of some important trials of steel wire-rope hawsers which have been lately made at Portsmouth Dockyard, the results being such as to astonish the operators as to the enormous tensile strength which had been impartod to the wire. Breed is not only entering largely into tho construction of our ships of war, but, their standing rigging and hawsers are being gradually made of the same light and durable material, and in a short time the London Times expects that the present unwieldly chain cables in use will be superseded by steel wire cables of moderate thickness and weight. The recent tests at Portsmouth were of various samples of steel wire hawsers for towing purposes, it having been found from the experience of the Valorous and other ships that a wire hawser possesses equal flexibility to the hest hempen rope, combined with less weight, superior handiness, and greater endurance, without any increase in the first cost. Official experiments at Portsmouth have also established the fact that the breaking strain of a steel hawser is more than three times that of arope hawser. Thus a9 in. ordinary hawser will break under a strain of 164 tons, and a 19 in. hawser under a strain of 72 tons, whereas Bullevant & Co’s 3in. steel hawser hroke at 18 tons, and tbeir 6 in. hawser at 80 tons. In the matter of weight the advantage is also clearly on the side of the steel, the 3 in. and Gin. wire hawsers weighing 7 Ibs. and 29 Ibs. per fathom, while the 9 fin. and 19 in, hempen hawsers weighed 19 lbs. and 84 lbs. per fathom. The samples operated upon were respectively of the circumference of 3, 4, 5 and 6in. The core of each was formed of tarred hemp, over which was twisted 6 strands, each strand being composed of 19 highly-tempered steel galvanized wires. The 3 in. hawser, which was formed of 15 gauge wire, broke at 224 tons; the 4 in. 14 gauge, at 353 tons; the 5 in., 12 gauge, at 573 tons; and the Gin. 10 gauge, at the enormous strain of 1003 tons. In every instance the strauds parted at the splicing, which were the only parts displaying any appreciable elongation under the tests. PROURESS OF THE Metric SysteM.—The Boston Society of Civil Engineers has the distinction of being the first organized professional body in the United States to make a ayatematic effort to secure the introduction of the metrival system of weights and measuree into general use in this country. The society appointed a committee, whose duty it was to open communication with the various learned societies and leading manufacturers throughout tbe country, and secure the favorable action of Congress upon a memorial fixing a date for the official adoption of the metrical system, by the potency of a combined appeal from these intuential sources. The report of this committee now before us, says the Polytechuic Review, after showing that the metrical eystem is steadily growing in favor in this country, states that 29 replies were received from eocieties which were addressed as above noted. Of these replies, 16 were favorable, 5 unfavorable and § undecided. On the unfavorable list, the American Academy of Arts and Sciences indefinitely postponed the matter by a vote of 10 to S, on the ground that ‘it would be a hardship to deprive the people of their preseut standards if they preferred to use them;” and the Franklin Institute rendered its decision in favor of the sweeping etatement ‘“‘that the objections to the attempt to adopt the meter as a standard unit of linear measure are overwhelming.” These two bodies are the moet prominent objectore, & a SCIENTIFIC ‘PROGRESS.

Geometrical Chemistry. We gave at the time of its first appearanco a synopsis of a thoory of # geometrical chemistry as proposed by Prof. Henry Wurtz. We notice now by the /ron Age, tbat the faculty of the Stevens Institute of Technology have paid a graceful tribute to American proses in science, by conferring the honorary degree of Doctor of Philosophy upon Prof, Menry Wurtz, A. M., for original research, and especially for tho discoveries upon whicb he bases his remarkablo theory of geometrieal chemistry. As this is the first time the faculty have used the power to confer honorary degrees, and as the faculty, which includes such cminent scierftists as Morton, Thurston, Mayer, Leeds and Wood were wuauilmous in the opinion that Prof. Wurtz’s discoveries were of sutticient value to merit the highest honor in their gift, the compliment is one of which any man of science might be proud. Prof. Wurtz has discovered a great number of facts in relation to the mathematical relations of molecular volumes—facts which had previously becn entirely unsuspected as well as unknown, ‘Tho first poiut sought by Prof. Wurtz was a standard temperature of nature. This he very conclusively demonstrates to be the temperature of ice at the point of incipient . 7, fusion. This found, the first fact discovered was that the volume of all single chemical molecules with one exception, are expressed by quantities which have the relations of even cubes of whole numbers, The one exception is oxygen, the inolecular volume of which, deduced from a comparison of water with peroxide of hydrogen, is 5,184, or three times the cube of 12, Calculations made upon the immense number of density terminations, fails to show that oxygen ever changes this volume—or diameter, as it is perhaps more appropriately called. Another discovery is the fact that hydrogen is the most vaviable of all the elements. It is fouud that molecules which combine to form a new substance, tends to assume very nearly the same size. Again, the tendency to vary increases with the electro-positive nature of theelement. Later researches develop the fact that, iu many different series of compounds, the diameter of some one element or elements vary in different members of tbe series by four units. The significance and importance of these facts alone are enough to render Prof. Wurtz’s labors worthy of high honors. Matine amone Frsnes.—A writer in a Berlin contemporary contributes some details of his experiences in pike fishing, which tend to show that the idea commouly entertained that the removal of the male fish from a water about spawning time has less effect upon the stock than the capture of the females, is altogether erroneous. Four or five weeks before spawning commences the jack seek the neighborhood of the shore in gronps, and he has invariahly observed that each of these consists of one female accompanied by one or more male fish, and so continues, unless disturbed, till the breeding season is over. Asa rule a female of small size is accompanied by one male only; a medium sized mother-fish has two or three males, and a full sized one as many as four or five. The larger the mother-fish the smaller, asa rule, are her attendant squires, the weight of the former being generally about equal to that of all the males put together. If the males of a group be caught shortly before spawning time, the bereaved female does not mate again that season; in due time of course she deposits her roe, but it remains unfertilized, and so perishes. By removal of some of tbe dorsal scales from all the memhers of the group taken in a net, so as to render their identification easy, it was found that on replacing them in the water at considerable distances from each other, they invariably reunited in a very short space of time. Under no circumstances was the spawn of a female bereaved of her attendant males, impregnated by tbe milt of others in the same water, however numerous the latter might be. A New Series of Onsecrrves.—At the latest meeting of the S. F. Microscopical Society, a letter was presented from Charles A. Spencer, of Geneva, New York, which was received in answer to an enquiry about ‘‘ Spencer’s Objectives.’ Among other things Mr. Spencer writcs: “From notices in the London Microscopical Journal, the American Naturalist, the American Journal of Microscopy, the Cincinnati Medical Neus, etc., it is quite evident that your Microscopical Society is alive one, and a gratifying fact it is to all devotees of science. I would give a cordial expression to the hope that its future progress may fulfill its present promise of being an honor to us all.” In answer to an enquiry, Mr. Spencer gave a description of a new eeries of objectives he was working up, in which he has it ag a special aim to produce ‘‘a series of objectives of quite moderate prices, yet of a high grade of excellence and of such almost absolute uniformity of quality thatthepurchaserneed have no fear of disappointment in this respect.” It is probable that the Society will have the opportunity of testing Mr. Spencer's new work. He is among the foremost of the optical instrument makers of this country; haviug made the telescope with which Professor C. H. F, Peters, of Hamilton College observatory, has discovered more asteroids than any other single observer, and a microscope for the late Professor Agassiz. Pitury—A New Stimulant. We learn from Nature, that Baron Von Mueller in a recent letter to the stustralian Medical Journal describes the origin of tbe Pitury, a stimulant said to be of marvellous power, and known to be in use by the aborigines of Central Australia. After years of efforts to get a speeimen of the plant, he had obtained leaves, but neither flowers nor fruits. He can almost with certainty, after due microscopic examination, pronounce those of the Pitury as derived from his Dubotsia Hopwoodti, described in 186) (Fraqm, Phytogr, Austr., [1,, 138). This bush extends from the Darling river and Barcoo to West Australia, through desert scrubs, but is of exceedingly sparse occurrence auywhere. In fixiny the origin of tho Pitury, a wide field for further inquiry is opened up, inasmuch as a second species of Duboixia (D, myoporoides RF. Br.) extends in forest land from near Sydney to near Cape York, and is traced »lso to New Caledonia, and latcly by him also to New Guinea. In all probability this D. myoporoides shares the properties of D. fHopwoodii, as he finds that both have the same burning acrid taste. Baron Mueller adds; ‘*Though the first known species is so near to us, we never suspected any such extraordinary properties in it as arc now established for the later discovered vo Moreover, the numerous species of the allied genus Anthocercis, extending over the greater part of the Australian continent and to ‘asmania, should now also be tasted, and further the many likewiso cognate Schwenkeas of South America should be drawn into the same cyclus of research, nothing whatever of the properties of any of these plants being known, The natives of Central Anstralia chew the leaves of Duboisia Hopiwoodéi, just as the Peruvians and Chilians masticate the leaves of the coca (Lrythroxylon coca), to invigorate themselves during their long foot journeys through the deserts. Iam not certain whether the aborigines of all districts iu which the Pitury grows are really aware of its stimulating power. Those living near tbe Barcoo travel many days’ journey to obtain this, to them, precious foliage, which is carried always about by them broken into small fragments aud tied np in little bags. It is not improbable that a new and perhaps important medicinal plant is thus gained. The blacks use the Duboisia to excite’ their courage in warfare—a large dose infuriates them.” No Bones in tHe OceAn.—Mr, Jeffrey has establisbed tbe fact that bones disappear in the ocean, By dredging, it is common to bring up teeth, but rarely ever a bone of any kind; these, however compact, dissolve if exposed to the action of the water but a little time. On the contrary, teeth—which are not bones any more than whales are fish—resist the destroying action of sea-water indefinitely. It is, therefore, a powerful solvent. Still, the popular opinion is that it is a briue. If such were tbe case,the bottom of all seas would, long ago, have been shallowed by immense accumulatiou of carcasses and products of the vegetable kingdom, constantly floating into them. Deutine, the pecnliar material of which teeth are formed, and the enamel covering them, offer extraordinary resistance to these chemical agencies, which resolve otber animal remains into nothingness, Mounds in the West, tumuli in Europe and Asia, which are believed to antedate sacred history for thousands of years, yield up perfectly sound teeth, on which time appears to have made no impression whatever. Mexico.—We are pleased to receive asample of what our sister repuhlic of Mexico is doing in the way of increasing knowledge of her development and_ resources of different kinds. Last February there was issued the first number of an official periodical entitled ‘‘Anales del Ministerio de Fomento.” This branch of the government has cognizance of all internal improvements, both of public aud private expeuse, and all scientific exploration to ascertain the topography, geography and various resources of the different Mexican States, The publicatiou of information of this valuable nature under the approval of the government, carries assurance of its accuracy and trustworthiness, and will be hailed with pleasure by many who are waiting for more knowledge of the Mexican republic; believing that the country is indeed a cornucopia in nature as well as form, The first numbers of the ‘‘Anales” show that the work of making the country known to her own citizene and foreigners is to be done scientifically and creditably. Our acknowledgements are due to the Hou. Riva Palacio for copies of the ‘fAnales.” Giant Powprr in Arctic EXpLoratrions,— The accounts of the English Arctic expedition under Capt. Nares, show the application of many devices supplied by tbe advancement of science in overcoming the many obstacles presented by nature to guard the approach to the pole. Electricity made day of the five months of night, while dynamite opened the way throngh heretofore unsurpassable ice barriere. Cartridges of dynamite were eimply placed upon the surface of the ice and their explosion was eufficient to cleat a passage. Where large masses of ice were encountered, miues were dug, the cartridges placed therein, and the passage choked up with ice blocks so as to increase the effect of the exploeion. By simultaneously exploding of a number of these mines, open tracts for the passage of the vessels were easily obtained.