Volume 17 (1868) (428 pages)

The Mining and Scientific Press. 195 Mechanteal, A New Dynamometer, or Force Measurer, from Oregon. A Dynamometeris an instrument for measuring force, in mechanics. Its usu is to determine tho force uscd or necessary to be used in driviug any given machiae or purt. The want of au instruwont of this kind, which would accurately registor power, has hecn felt hy mechanics over since tho iuventiou of ninchiuery, and huudreds if not thounuids of unsuccessfol attempts havo heeu wado to construct such au uno. An editorial writer iu the Scientific American mentions some of the errors iuto which tho best engiuecrs havo always fallen iu calculuting tho powers absorhed by veuted machiuery, aud deplores the fact that uo ac curate method of measuring force has ever been fouud. Itsays : ‘* Thorough method of calculating the amount of power delivered or trausmitted, by the width of the driveu belt -a plau which was eommon enough a few years ago aud may be uow—is as ridicnlons and as tar from the trnthas the formula of the astronomical iustructor who taught the pupils, iu estimating thedistance of the fixed stars trom our planct, to guess at the distance aud multiply by four.” A paper by one of the most eminent English engiheers, ou this snhject, after mentiouing aud desernbiug two of the best instrumouts ia uso, says: ‘‘ We fiud ourself compelled in the tace of those two hest indicators yet made, to declare that an ahsolutely pertect instrument of the kind remains yet to he iuyouted.” There seems to be no dificulty iu measuring force exerted in a straight liue ; the trouble is to calculate power exorted iu a rotary direction, especially whero it is irregular or eccoutric, as in cam movemeuts. We have some assurance that this dificulty is about to be overcome hy an inveution of our fellow-townsman, John W. Suttou. He has constructed an instrument which, though notcomplete, isin operatiou at the Willamette Iron Works, and promises the most flattering and astonishing results. A numher of mechanics who haye examined it pronounce the most favorable opiniou of its accuracy, and it would seem that it can searccly fail to take the leading position amoag all the rotary dynamometers known. It would be useless to undertake an intelligible description of it without ample means of illustration; hut we can give 2 general idea of the principle upon which it works. It eousists of two disks placed upon a shaft and 2 hollow shaft so that they may move relatively without appreeiable friction. One of these disks is fastened to the driving pulley ; the other to the main shaft. ‘The two disks are attached by means of spiral springs. When the driving pulley starts, it carries the attached disk and thatin turn, by means of the spiral spring eonneetion, drags after it the other disk which is attaehed to and turns the shaft. ‘The springs, of eourse, are drawn out by the advanee movement of the tirst disk and the lagging movement ot the other. Therelative movement or ehange of position of the two disks, by meaus of cog geariag within moves a eogged rack, back and forth as the power is inereased or diminished aud as the two disks ehange their relative positions. The rack movesa coliar along the shaft and hy an indicating point registers the power. The spiral springs are drawn or elongated, and contracted accordiug as the strain of the driving power and the resisting machinery is greater or less. The disks ehange relative positions iu exact proportious, and every change, however minute, is marked by the indivator upon the gauge. Thusif it he known how much power it requires to elongate the springs a given distance, it beoomes a simple mathematical ealeulation involving only rules well known to engineers, to determine the force applied, or what is equivalent, the resistaneeof the machinery. Mr. Sutton’s instrument has a gange based upon these ealculations, which may he made to show at auy instant the number of horse powers, or thousands of pounds, or even pounds, of force exerted. He has filed a caveat tor a patent and taken all the necessary steps to procure it. The model muy be seen for a few days at the Willamette Iron Works, where it is now being finished. AJl the mechanics who have seen it say that Mr. Sutton has eertainly made au important and valuable discovery.—/ortland Oregonian. Srezn Bormers.—Boile’ plates made of cast steel havo recently been suhjeeted to a series of practical experiments, in order to test their value as eompared with those made of wrought iron. The trials were made at Harkett’s Ironworks, in Westphalia, and the results are reportod to have been decidcdly in favor of steel. CiearSream Excixes,—An English manufacturiug firm has recently brought out a novelty in steain engines, as far as relates to the price, in n two-horse power horizontal engiue, of good construction, which is sold for the sum of eighteenpounds. Considerable credit isdue to the manufacturers of such an eagine, for the skill required in desiguing it to meet such conditions. ‘This is tho liae of march that Progress must take in regard to the steam engine. Bripeine tue Mississipri ar St, Lovts. The construction of a bridge across the Mississippi has been commenced under the engineering of Capt. J. B. Hads, who has se. lected a spot whore the river is 1,500 feet wide, and proposes three spans, the ceuter of which is 515 feet, and the two side ones 497 feot each, The bed of tho river is a shifting mass of saud overlyiag a hed of rock to a considerable depth, involving tho construction of a pier 145 feet in height from the rock to the lower roadway. Tron SamevtinG Orrrations In Mexico.— An euterprisiag Eaglish company, after overcoming almost insurmountable difficulties, have established two extensive ironworks at Zimapan, in Mexico. In these works steady employment is given to hetween 500 and 600 native laborers, aud over 600 tons of irou are annually manufactured into bars or other varieties of merchantable iron, and sent to the City of Mexico ever a difficult mountain road, built and kept in condition hy this company, at their own expense, the Government never contributing in labor or money to its construction. North of China Gold Mines. Dr. Macgowan, who is occupied in preparing a work in Chinese on ‘‘ Mining and Metallurgical Opperations for the Govornment of China,” sends us tho following information respecting the newly discovered gold mines in the north of China: The intelligence of tho discoveries of gold iu the Promoutory of Shantung will have reached San Francisco by precoding mails, and have occasioned, I apprehend, some excitement among the hardy, restless and adventurous miners of California aud adjacent miuiug regions. I shall not say that reports have been transniitted to Californiaand Australia with the design of creating an excitement amongst their nomadic inhabitants, but Tean affirm that there is no eoneealment on the part of many here of the desire they entertain for an arrival} of Californian and Australian fillihnsters ; nor is the object of that desire eoneealed, that objeet being the employment of miners to revolutionize the eountry at least to the extent of overthrowing Chinese exclusiveness; in other words, to render nugatory such treaty obligations as are distasteful to foreigners. The well-heing of those who are to bring ahout those ehanges is as little eonsidered as the feelings of Chinameu in the matter. Considerations of this uature, and the requirements of good faith, have induced the Consuls of the various treaty powers to notify their nationals that until the Imperial Goverument sees fit to ehange its poliey, they will aid the Chinese in enforcing the laws. As these laws prohihit the working of the mines alike to natives and foreigners, our mining friends should eousider well the situation before expatriating themselves. There is another consideration which deserves attention, and which many miners can appreciate even in California and Australia: Chinamen can afford to work cheaper than white men, and it is likely that with the additional advantage of being at home, ho ean so eompete with the foreigner as to impoverish the latter. It has been predicted that within a few months we shall havearush of miners here, numhering some two thousand. The prophesy was to effeet that immigration, and if the mines should prove nuproduetive the} men thus allured are likely to he great suf-} ferers. With regard to the produetiveness of the diggings, nothing can be positively affirmed. It is almost demonstrated that rich auviferous quartz is ahundant; also; silver, eopper and coal. But whether or uot the miner, whose capital is his hands, ean delve and live, is more than any man ean say at present. On these grounds I counsel American . miners to stay at home. . Setentific Miscellany. Familiarity With and Uses. Magnetism. of ElectroWere it uot for the two great discoveries of telegraphy and olectro-metallurgy the greater portion of our knowledge of electricity would be contined to scieutific men. . From unnumbered experiments that have hecn made, it seems the generation of electricity is n pheuomenon generally attcudant upou the contact or conjunction of two materials of different natnres; thns, not only may it be derived from the decomposition of zino in an ordiuary gulvanio battery, but also by the simple contact of the zine with anothor metal, as with iron, the tension of the electrical current, being in either case proportioned to the rapidity with which tho zine is oxidized. In like manner experimental batteries have been made simply of alternate layers or slices of two different kinds of vegetables, and also of alternate disks of two different varieties of wood. Pins or bolts of one variety of wood driven into the hulls of ships formed ot another variety, have been found to produce currents of appreciahle strength, and sufficient to affect the adjacent metallic sheathing. Amongst the later applications of electricity to utilitarian purposes are the Saxby method of detectiag flawsiniron, by which the deflection of the needle when passed along an iron bar or shaft indicates the want of homogenconsness in the metal, and the resulting unreliability of the same; the electric test for the detection of adulteration in oils, devised some years ago hy a French savant, and since extended hy an English experiment founded upon the discovery that the number of vibrations and the degree of resistance of the magnetic needle, when made to form part of an electric eurrent, are affected by a given oil to a greater or less degree, according as the latter is more or less pure; and the experiments made hy M. Duchemiu, under the authority of the Freuch Governmeat, relative to the practical use of the electricity generated by the destruction of zinc in seawater, in which he has suceeeded in ringing an electrical bell for two months eontinnously, the suecess thus far attained encouraging the projector to propose other uses by similar means, as the proteetion from rust of the bottoms of iron-elads, by insuring communieation between the armor and a powerful pile placed in the sea-water. ‘Tan JAPANESE Earraquaku ALARM NoT Rew1aBte.—The following experiment was made by Mr. Henry G. Hanks, of this city, for the purpose of testing the reliability of the “Japanese Earthquake Alarm.” We give his own words: “Having heard the Japanese instrument deserihed, I made an experiment to satisfy myself whether it was true or otherwise. I proeured a small but powerful magnet which I suspended from the eeiling of my bed-room over my table. To the keeper I hung a small tin pan, like the pan of a balance. This I loaded eontinuonsly with weights until I had aseertained the full power of the magnet. I then hung a bar of irou of equal weight to the maguet without any other support than the attraction. It is evident that the slightest decrease of attractive power on the part of the magnet would have allowed the pan to fall. The weight of the bar was 2,578 kilogrammes— over five and a half pounds avoirdupois. This arrangement remained suspended for several months, the bar pointing steadily to the magnetie north. During this time we had several earthquakes. Even the motion did not shake down the suspended har. From this experiment I am led to helieve that the Japanese indicator is a myth, or that the earthquakes are governed hy different laws in Japan than they are on this side of the Pacific. Ihave since conversed with parties who have resided some timein Japan, upon the snbject. They have all heard of it, but Ihave failed to find any one who has seen it. Iwish the “story” could he traeed to its source, for such a statement should not go withont eontradieAxTIFICIAL Mixeratoay.—The following receipt for a foundation glass to make artificial precious stoncs, and the mineral coloring matter to beadded to make imitations of particular minerals, aro instructive to the student of mineralogy: M. Elsner recommeads tho taking of 45:7 grammes of pure quartz, 22°8 grammes of pure and dry carbonato of soda, 7°6 grammes of borax, 3-4 grammes of uiter, and 11-8 grammes of minium. Theso ingredients, reduced to a fine powder and well mixed, are bronght to perfect fusion in a Hessian crucible over a charcoal fire. To color this mass add, for sapphires, 0-106 grammes of carbonate of cobalt; for emeralds, 0-53 grammes of oxide of iron; for amethysts, 0-265 grammes of carhonate of manganese; for topaz, 1:59 grammes of oxide of uranium. Inall cases the fusion must be porfect, or a clear glass will not be ohtained. Cutting greatly improves these imitations. CarnonizatTion OF Woop.—M. Gillot, in his memoir to the French Academy of Sciences on this subject, says the only condition essential for the production of good charcoal, is that the operation shall proceed slowly. The decomposition of wood commences at ahout the hoiling point of water. In this way a given amount of wood will yield about two-thirds its weight of charcon and seven or eight per cent. of acetic acid, Manvracture or Sunpuurio Actp.—A new process for the production of sulphnrie acid has been patented in Franco by MM. Tardani and De Susini. Its great recommendation is that it dispenses with the large leaden chambers. The sulphur or pyrites is burned in compressed air, and the sulphurous acid is first washed to free it from arsenic, ete., and is then brought into contact with the nitric vapors in a small leaden chamber of peculiar constructiou.—Gas Light Journal. Cuarcoan Dust or Lame-Buack AS A Dismvrectant.—The disagreeable smell peculiar to india-rnbher may be got rid of hy means of charcoal and, better still, by lampblack, which, as is well known, has the property of shsorbing gaseous suhstauces. The articles to he disiafected are put into a close vessel, covered over with charcoaldust, aud theu exposed for a few hours to a temperature of from 60 to 70 degrees Ceutigrade, by means of a water bath. When the articles aro taken out the chareoal-dust is brushed off, and it will then he found that they have lost every trace of had smell. CaLIFoRNIA AND Nevapa Dryine up.—At the recent meeting of the Seientifie Association at Chicago, Prot. W. P. Blake read a short paper ‘‘ on the gradual desiccation of the western portion of North America.” He said that the interior lakes in the chain of the Sierra Nevada were giving ample evidence of wasting away, heing surrounded by water-lines, old beaches and terraces. Some of the existing lakes had broad tracts of lacustrine clay, extending a considerable distance from their present shores. The lakes of Mexico have also mueh narrower beds than formerly, and there were evidences of the decrease of water in them within historie times. There were no traees of volcanic action or any paroxysmal movement to produee so great a ehange. It was impossible to avoid the eonclusion that the gradual disappearance of these vast lakes was due not to ehanges of level but to grand climatic ehanges,—to a gradual deerease of precipitation whieh not only appeared to be continental but to be worldwide, iaasmuch as similar conditions were found in Central Asia and elsewhere. He referred to the gradual extinction of glaciers from the sonth northward, and regarded this as eonnected with the deerease of precipitation. Wiruin the last year business in Fol som has increased to a eonsiderable extent; new buildings have been erected, and real estate has taken an upward tendeney, and there has been a steady increase in popnilation, and eonfidenco in the future growth and prosperity of the town has heen fully tion. Ido uot know what sueh an earthquake as that lately experienced in South America might do, but my own experiwents have proved to me that our ordinary California earthquakes do not effect the attractive power of the magnet in the slightest degree.” . estahlished. Turre are 13 steam threshers now at work in Salinas Valley, Santa Cruz eonnty, threshing out an average of 500 hushels per day, and there is a demand for at least eight more.

The Mining and Scientific Press. 195 Mechanteal, A New Dynamometer, or Force Measurer, from Oregon. A Dynamometeris an instrument for measuring force, in mechanics. Its usu is to determine tho force uscd or necessary to be used in driviug any given machiae or purt. The want of au instruwont of this kind, which would accurately registor power, has hecn felt hy mechanics over since tho iuventiou of ninchiuery, and huudreds if not thounuids of unsuccessfol attempts havo heeu wado to construct such au uno. An editorial writer iu the Scientific American mentions some of the errors iuto which tho best engiuecrs havo always fallen iu calculuting tho powers absorhed by veuted machiuery, aud deplores the fact that uo ac curate method of measuring force has ever been fouud. Itsays : ‘* Thorough method of calculating the amount of power delivered or trausmitted, by the width of the driveu belt -a plau which was eommon enough a few years ago aud may be uow—is as ridicnlons and as tar from the trnthas the formula of the astronomical iustructor who taught the pupils, iu estimating thedistance of the fixed stars trom our planct, to guess at the distance aud multiply by four.” A paper by one of the most eminent English engiheers, ou this snhject, after mentiouing aud desernbiug two of the best instrumouts ia uso, says: ‘‘ We fiud ourself compelled in the tace of those two hest indicators yet made, to declare that an ahsolutely pertect instrument of the kind remains yet to he iuyouted.” There seems to be no dificulty iu measuring force exerted in a straight liue ; the trouble is to calculate power exorted iu a rotary direction, especially whero it is irregular or eccoutric, as in cam movemeuts. We have some assurance that this dificulty is about to be overcome hy an inveution of our fellow-townsman, John W. Suttou. He has constructed an instrument which, though notcomplete, isin operatiou at the Willamette Iron Works, and promises the most flattering and astonishing results. A numher of mechanics who haye examined it pronounce the most favorable opiniou of its accuracy, and it would seem that it can searccly fail to take the leading position amoag all the rotary dynamometers known. It would be useless to undertake an intelligible description of it without ample means of illustration; hut we can give 2 general idea of the principle upon which it works. It eousists of two disks placed upon a shaft and 2 hollow shaft so that they may move relatively without appreeiable friction. One of these disks is fastened to the driving pulley ; the other to the main shaft. ‘The two disks are attached by means of spiral springs. When the driving pulley starts, it carries the attached disk and thatin turn, by means of the spiral spring eonneetion, drags after it the other disk which is attaehed to and turns the shaft. ‘The springs, of eourse, are drawn out by the advanee movement of the tirst disk and the lagging movement ot the other. Therelative movement or ehange of position of the two disks, by meaus of cog geariag within moves a eogged rack, back and forth as the power is inereased or diminished aud as the two disks ehange their relative positions. The rack movesa coliar along the shaft and hy an indicating point registers the power. The spiral springs are drawn or elongated, and contracted accordiug as the strain of the driving power and the resisting machinery is greater or less. The disks ehange relative positions iu exact proportious, and every change, however minute, is marked by the indivator upon the gauge. Thusif it he known how much power it requires to elongate the springs a given distance, it beoomes a simple mathematical ealeulation involving only rules well known to engineers, to determine the force applied, or what is equivalent, the resistaneeof the machinery. Mr. Sutton’s instrument has a gange based upon these ealculations, which may he made to show at auy instant the number of horse powers, or thousands of pounds, or even pounds, of force exerted. He has filed a caveat tor a patent and taken all the necessary steps to procure it. The model muy be seen for a few days at the Willamette Iron Works, where it is now being finished. AJl the mechanics who have seen it say that Mr. Sutton has eertainly made au important and valuable discovery.—/ortland Oregonian. Srezn Bormers.—Boile’ plates made of cast steel havo recently been suhjeeted to a series of practical experiments, in order to test their value as eompared with those made of wrought iron. The trials were made at Harkett’s Ironworks, in Westphalia, and the results are reportod to have been decidcdly in favor of steel. CiearSream Excixes,—An English manufacturiug firm has recently brought out a novelty in steain engines, as far as relates to the price, in n two-horse power horizontal engiue, of good construction, which is sold for the sum of eighteenpounds. Considerable credit isdue to the manufacturers of such an eagine, for the skill required in desiguing it to meet such conditions. ‘This is tho liae of march that Progress must take in regard to the steam engine. Bripeine tue Mississipri ar St, Lovts. The construction of a bridge across the Mississippi has been commenced under the engineering of Capt. J. B. Hads, who has se. lected a spot whore the river is 1,500 feet wide, and proposes three spans, the ceuter of which is 515 feet, and the two side ones 497 feot each, The bed of tho river is a shifting mass of saud overlyiag a hed of rock to a considerable depth, involving tho construction of a pier 145 feet in height from the rock to the lower roadway. Tron SamevtinG Orrrations In Mexico.— An euterprisiag Eaglish company, after overcoming almost insurmountable difficulties, have established two extensive ironworks at Zimapan, in Mexico. In these works steady employment is given to hetween 500 and 600 native laborers, aud over 600 tons of irou are annually manufactured into bars or other varieties of merchantable iron, and sent to the City of Mexico ever a difficult mountain road, built and kept in condition hy this company, at their own expense, the Government never contributing in labor or money to its construction. North of China Gold Mines. Dr. Macgowan, who is occupied in preparing a work in Chinese on ‘‘ Mining and Metallurgical Opperations for the Govornment of China,” sends us tho following information respecting the newly discovered gold mines in the north of China: The intelligence of tho discoveries of gold iu the Promoutory of Shantung will have reached San Francisco by precoding mails, and have occasioned, I apprehend, some excitement among the hardy, restless and adventurous miners of California aud adjacent miuiug regions. I shall not say that reports have been transniitted to Californiaand Australia with the design of creating an excitement amongst their nomadic inhabitants, but Tean affirm that there is no eoneealment on the part of many here of the desire they entertain for an arrival} of Californian and Australian fillihnsters ; nor is the object of that desire eoneealed, that objeet being the employment of miners to revolutionize the eountry at least to the extent of overthrowing Chinese exclusiveness; in other words, to render nugatory such treaty obligations as are distasteful to foreigners. The well-heing of those who are to bring ahout those ehanges is as little eonsidered as the feelings of Chinameu in the matter. Considerations of this uature, and the requirements of good faith, have induced the Consuls of the various treaty powers to notify their nationals that until the Imperial Goverument sees fit to ehange its poliey, they will aid the Chinese in enforcing the laws. As these laws prohihit the working of the mines alike to natives and foreigners, our mining friends should eousider well the situation before expatriating themselves. There is another consideration which deserves attention, and which many miners can appreciate even in California and Australia: Chinamen can afford to work cheaper than white men, and it is likely that with the additional advantage of being at home, ho ean so eompete with the foreigner as to impoverish the latter. It has been predicted that within a few months we shall havearush of miners here, numhering some two thousand. The prophesy was to effeet that immigration, and if the mines should prove nuproduetive the} men thus allured are likely to he great suf-}

ferers. With regard to the produetiveness of the diggings, nothing can be positively affirmed. It is almost demonstrated that rich auviferous quartz is ahundant; also; silver, eopper and coal. But whether or uot the miner, whose capital is his hands, ean delve and live, is more than any man ean say at present. On these grounds I counsel American . miners to stay at home. . Setentific Miscellany. Familiarity With and Uses. Magnetism. of ElectroWere it uot for the two great discoveries of telegraphy and olectro-metallurgy the greater portion of our knowledge of electricity would be contined to scieutific men. . From unnumbered experiments that have hecn made, it seems the generation of electricity is n pheuomenon generally attcudant upou the contact or conjunction of two materials of different natnres; thns, not only may it be derived from the decomposition of zino in an ordiuary gulvanio battery, but also by the simple contact of the zine with anothor metal, as with iron, the tension of the electrical current, being in either case proportioned to the rapidity with which tho zine is oxidized. In like manner experimental batteries have been made simply of alternate layers or slices of two different kinds of vegetables, and also of alternate disks of two different varieties of wood. Pins or bolts of one variety of wood driven into the hulls of ships formed ot another variety, have been found to produce currents of appreciahle strength, and sufficient to affect the adjacent metallic sheathing. Amongst the later applications of electricity to utilitarian purposes are the Saxby method of detectiag flawsiniron, by which the deflection of the needle when passed along an iron bar or shaft indicates the want of homogenconsness in the metal, and the resulting unreliability of the same; the electric test for the detection of adulteration in oils, devised some years ago hy a French savant, and since extended hy an English experiment founded upon the discovery that the number of vibrations and the degree of resistance of the magnetic needle, when made to form part of an electric eurrent, are affected by a given oil to a greater or less degree, according as the latter is more or less pure; and the experiments made hy M. Duchemiu, under the authority of the Freuch Governmeat, relative to the practical use of the electricity generated by the destruction of zinc in seawater, in which he has suceeeded in ringing an electrical bell for two months eontinnously, the suecess thus far attained encouraging the projector to propose other uses by similar means, as the proteetion from rust of the bottoms of iron-elads, by insuring communieation between the armor and a powerful pile placed in the sea-water. ‘Tan JAPANESE Earraquaku ALARM NoT Rew1aBte.—The following experiment was made by Mr. Henry G. Hanks, of this city, for the purpose of testing the reliability of the “Japanese Earthquake Alarm.” We give his own words: “Having heard the Japanese instrument deserihed, I made an experiment to satisfy myself whether it was true or otherwise. I proeured a small but powerful magnet which I suspended from the eeiling of my bed-room over my table. To the keeper I hung a small tin pan, like the pan of a balance. This I loaded eontinuonsly with weights until I had aseertained the full power of the magnet. I then hung a bar of irou of equal weight to the maguet without any other support than the attraction. It is evident that the slightest decrease of attractive power on the part of the magnet would have allowed the pan to fall. The weight of the bar was 2,578 kilogrammes— over five and a half pounds avoirdupois. This arrangement remained suspended for several months, the bar pointing steadily to the magnetie north. During this time we had several earthquakes. Even the motion did not shake down the suspended har. From this experiment I am led to helieve that the Japanese indicator is a myth, or that the earthquakes are governed hy different laws in Japan than they are on this side of the Pacific. Ihave since conversed with parties who have resided some timein Japan, upon the snbject. They have all heard of it, but Ihave failed to find any one who has seen it. Iwish the “story” could he traeed to its source, for such a statement should not go withont eontradieAxTIFICIAL Mixeratoay.—The following receipt for a foundation glass to make artificial precious stoncs, and the mineral coloring matter to beadded to make imitations of particular minerals, aro instructive to the student of mineralogy: M. Elsner recommeads tho taking of 45:7 grammes of pure quartz, 22°8 grammes of pure and dry carbonato of soda, 7°6 grammes of borax, 3-4 grammes of uiter, and 11-8 grammes of minium. Theso ingredients, reduced to a fine powder and well mixed, are bronght to perfect fusion in a Hessian crucible over a charcoal fire. To color this mass add, for sapphires, 0-106 grammes of carbonate of cobalt; for emeralds, 0-53 grammes of oxide of iron; for amethysts, 0-265 grammes of carhonate of manganese; for topaz, 1:59 grammes of oxide of uranium. Inall cases the fusion must be porfect, or a clear glass will not be ohtained. Cutting greatly improves these imitations. CarnonizatTion OF Woop.—M. Gillot, in his memoir to the French Academy of Sciences on this subject, says the only condition essential for the production of good charcoal, is that the operation shall proceed slowly. The decomposition of wood commences at ahout the hoiling point of water. In this way a given amount of wood will yield about two-thirds its weight of charcon and seven or eight per cent. of acetic acid, Manvracture or Sunpuurio Actp.—A new process for the production of sulphnrie acid has been patented in Franco by MM. Tardani and De Susini. Its great recommendation is that it dispenses with the large leaden chambers. The sulphur or pyrites is burned in compressed air, and the sulphurous acid is first washed to free it from arsenic, ete., and is then brought into contact with the nitric vapors in a small leaden chamber of peculiar constructiou.—Gas Light Journal. Cuarcoan Dust or Lame-Buack AS A Dismvrectant.—The disagreeable smell peculiar to india-rnbher may be got rid of hy means of charcoal and, better still, by lampblack, which, as is well known, has the property of shsorbing gaseous suhstauces. The articles to he disiafected are put into a close vessel, covered over with charcoaldust, aud theu exposed for a few hours to a temperature of from 60 to 70 degrees Ceutigrade, by means of a water bath. When the articles aro taken out the chareoal-dust is brushed off, and it will then he found that they have lost every trace of had smell. CaLIFoRNIA AND Nevapa Dryine up.—At the recent meeting of the Seientifie Association at Chicago, Prot. W. P. Blake read a short paper ‘‘ on the gradual desiccation of the western portion of North America.” He said that the interior lakes in the chain of the Sierra Nevada were giving ample evidence of wasting away, heing surrounded by water-lines, old beaches and terraces. Some of the existing lakes had broad tracts of lacustrine clay, extending a considerable distance from their present shores. The lakes of Mexico have also mueh narrower beds than formerly, and there were evidences of the decrease of water in them within historie times. There were no traees of volcanic action or any paroxysmal movement to produee so great a ehange. It was impossible to avoid the eonclusion that the gradual disappearance of these vast lakes was due not to ehanges of level but to grand climatic ehanges,—to a gradual deerease of precipitation whieh not only appeared to be continental but to be worldwide, iaasmuch as similar conditions were found in Central Asia and elsewhere. He referred to the gradual extinction of glaciers from the sonth northward, and regarded this as eonnected with the deerease of precipitation. Wiruin the last year business in Fol som has increased to a eonsiderable extent; new buildings have been erected, and real estate has taken an upward tendeney, and there has been a steady increase in popnilation, and eonfidenco in the future growth and prosperity of the town has heen fully tion. Ido uot know what sueh an earthquake as that lately experienced in South America might do, but my own experiwents have proved to me that our ordinary California earthquakes do not effect the attractive power of the magnet in the slightest degree.” . estahlished. Turre are 13 steam threshers now at work in Salinas Valley, Santa Cruz eonnty, threshing out an average of 500 hushels per day, and there is a demand for at least eight more.