Volume 11 (1865) (424 pages)

J a ournal of Aseful Arts, Srienee, nnd a ining and Rlechanical Progress. DEWEY & €O,, PUBRLISREES; -And Patent Sollelioce. b) VOLUMEXI. Number 6, SAN FRANCISCO, SATURDAY, AUGUST 26, 1865. Oo, W. M. suri. DPDEWEY & CO., Publishers. W, B. EWER. 4. T. DEWEY. ——_— Orricr—No, 505 Clay streel, corner of Sansome, 2d floor. ‘Terma of Subseriptions +35 00 Once copy, per annum, In alvance,. macs 0g . AED One copy, xx montha, in wlvanee,. gg For sale by Carriers and Newsdeale Tt is ¥Empnestble for editors to know aut the merits and demerits of their currespondence, conseqnenily the Fender aust not recelve the sully of our contributors ato hn. Intelligent discussion ls invited npou all sides andthe evidence of nny crror which nay wppear will be recelved In friendship aid trcaled with respect. . Amertean and Foreien Patents.—Lelters Patent for Inventorseanbe secured Inthe Uuited States and foreken countries through the MastxG asn Scigstiric Parss Pater Acxyxcy. We oifer apoileants renomable terms, and they enn rest ascured of a strict compllance with our obligations, and a falthful For reference, { perronnnnse of all contrnets. we wii furulsh the names of numerous partles for whom we have obtalned patenie during Ihe past twe yenrs. Pavorable to Tnventors.—Persons holding new Inveutlous of machinery and important Improvements, can have the same Illutirated nnd explalned in lhe Mixine ann Sorxtinio Press, treo of charge, lf In our judgment the discovery Is one of real merfl, and of sutficlent Interest to our renders to warrant publication. Payment in Advance.---Thla paper will not he sent tosubserlbors beyond the lerm pald for. The publishers well know that a good journal cannot be snstalned on the credit system. During the Fair Wo hope the readers of the Mixtna anv Screstiric Prers will look with leniency upon any degression they may obe@rve from the asunl contents and make-np of our journal. Correspondents -will also pleasa hear patlently wilh the erowited slale of our columna la glylug full reporis of the Exhibition. Ork PaprR py Express.—Owing to the fact of Wells Fargo & Co reqniring publishers lo pay 23 cents per copy fn ndyanee oa papers sent to subseribers in the inlerior we are obliged to make our subscription terms by express $6.50 per annum, a Tur Stones or tur Treapre.—The marble stones which composed Solomon’s Temple were said to be forty cubics long twelve thick and eight hich. Suposing a cubic to be eighteen inches, which is the lowest estimate, they would be sixty feet long, cighteen feet thick, and twelve feet high. And supposing n cubic faot of marble to weigh 2,707 ounces, one of these stones weighed 2,752,038 pounds and 12 ounces. And supposing one man to be able to raise 200 pounds, it will require 13,760 nen to raise one of these, and also a little boy who could raise 38 pounds 12 ounces. And suppose ono man to require a square yard to stand upon, it would reqnire 2 acres, 3 roods, 11 perches and 12 yurds for them to stand upon while raising it, besides a place for the little boy to stand. What floats must have been necessary to carry tlicai across the sea to Joppa! And whnt kind of teams, as well us wagoas, do you suppose they had to carry these stones from Joppa to Jerusalem, which is about thirty miles, and a mouatainous country? And what ski!l was necessary to square and dress these immense stones, so that when they were brought together they fitted so exactly that they lad the appearance of being one solid stone. A wave on which many a poor fellow has been carried away is the, wave of a lace-edged cambrie handkerchief. Aut notibility ia its begianings was soniebody’s natural superiority. Tue Richmond Christian Observer is the only religious newspaper now alive iu the Southern States. Perr no faith im a new promise based on th “proved to me that there was a chemical cont(Written tor the Minlag nnd Seientlfic Press. j Colorado Gold Processes. FEoirons Mininé ano Scirntivic Press :— Ina number of your valuable journal, some weeks ago, I noticed an extrnet of a portion of a’ Circular” on some mining processes and machinery that [ issued here about Moreh Ist, 1865, but which was incorrectly copied, so as tu injure its merits. Iu your issuo of May 20th and the week previous, there nre notices of “ Messrs. Crosby & ‘Lhompson’s Process and Machinery.” As theirs and my owu are somewhat similarin parts,and aslam partially acquainted with those gentleincu and their experiments, with your permission I would like to muko some commeuts on their ideas nnd your statements, and some explanations of the points involved in my own inventions, 70 bono publico. You remark of Messrs. C. & ‘T's process, that their assuinption that gold exists in nature as a sulphide, or in a volatile condition, capable of being condensed, “ is without a shadow of proof,” and that “their experiments appear to have been confiued to conceatrated sulphurets, nearly free from quartz.” ‘To this Ianswer, that most of the workable ores in this eonntry arc of that description, eoataining nsually sulphides of gold, silver, copper, and often lead, all mixed together, with fine quartz erystals, aad some quartz unerystalized. In elaborate .experitments on these ores three years ngo, I found in aearly all of them atneral oil, as well as sulphur and arsenie, in quantity, aud other base metals. Ly roasting pulverized ores in a common fire toa red heat, and then plungiug thei red hot into cold water, I separated the copper by precipitation on the bottota of the iron vessel, aad floated off the mineral oil. Iu some instances, where the hcat was at a low red temperature, upon panning down the powdered ore after the above treatment, 1 found the gold in fine scales at the bottom of the pan, and though yellow, yet quicksilver would not tonch them until Ire-heat them with soda or alum, when they lost their yellow hue and amalgamated without difficnlty. Now that ing over the gold in sack pyritous ores that by no process or machinery in use at present, nnless it might be Mr. Crosby's, or those of my own invention, described partially in the accompanying “ Circular,” could the precious metals thereiu contained be saved. So I conclude that inmost of the gold in Colorado ores + but re discovered, exist therein in the state of a sulphide. [We do not see the reason for any such inference, — En. M. aud S. Press.] Yhe silver-lead ores here are much easier treated, but scarcely anything caa be saved froin them by our mills, as they manage thei by the wet process; for the lead, oil and manganese therein fouls up the quicksilver and battery plates ia an hour or two,so that no metal can be caught or saved upon thet, . though these ores are froin. five to ten times as valuable in gold aud silver as the more common guld ores. Ja my experiments oh these I found that roasting them when pulverized with one-tweutieth of soda, by weight, would so soften and decompose thtir constituent particles, that no difficulty was afterward found in grinding gold, silver nnd lead alZ into amalgam . with mercury, and separating the lead [rom the ! breach of an old oue. : in Gerniany, which 1 hud not read or henrd of, Talso found that sulphur Was a great uid in combustion, ond that alum was nearly as good as borax forn Hux ; Inrther nore, that the three used together properly, in but sinall quantities, would flux the must stabboru of these stubborn minerals, and ¢éhese latter ores as freely as desired, precipitatiug all their precious conteuts directly, with but a moderate heat. Tam confident that with a furnace similar to the one described in the following extracts from uty * Circular,” that thc rich ores of Nevada, ns well as some in this and other sections, ‘cau be made to flow streams of precious inetals, especially with, (and in most iustances without) a hot alr blust. “There is a cluss of ores known as argentiferous galena, which, in addition contain yellow pyrites or sulphates of gold ; these are the richest ores in Colurado, containing often from five to ten dollars per ponud in gold and silver, and a quintity of lead, which has hitherto prevented the collection of the more valuable metals; iu most cases, however, they will yield to the treatment last described; if not, they can be readily jlu.ccd by the following receipe, at an expense of a few cents per round, which is not much when the yield produced thereby is of.en as many dollars : “Totimately mix with the pulverized ores one-tenth to one-twentieth by weight, each, of bi-carbonate or nitrate of soda and rosin ; place the compound in a cone-shaped. boiler-irou or other suitable crucible, and when brought up to a white heat pour into a cavity in the mid-, dle of the masa giinilar aud equal quantities by weight of pulverized borax aud sulphur, ov the same of sulphus and double of alum, which will produce ax dmmediate flux, precipitating the contained metals in a button of more or less parity ; the whole time required being soverucd by the quantity operated on, and the amount of lead in the ores treated.” “The Strelting Furnace designed for the Fluxing Process, is a circnlar stone structure lived with fire-proof Lrick or gneiss, with dome top and tall chinney. It has doors near the buttem for fuel, nnd another opening near the ton of the contained crucible, for the purpose of charging it. ‘fhe crucible may be made of boiler iron in the shape of a sharp cone, and il of large size,is to be provided with oue or more flues throngh its length. It is to be placed vertically in the centre of the furnace, with but a few inches spaco around its rim or larger part ; its top las half-section tron covers, hinged to the rin; a vessel to contain hot water is placed above the crucible, with faucet, to detach slag from the crucible. The crncible has an opeuing in one side, near the bottoin. with curved doors to fit, opening ontward into a square case pussing through the furnace walls to take out the refuse charges through, A curved irsn pipe of nn inch or two in diameter, screwed into or rivited oa the bottom of the crucible, and passing out throuzh the furnace wall serves to draw off the meltcd ores when sufficiently refined, into cold water, or into moulds. ‘The inner opening of the pipe is protecled froin stoppage by a coavex iron plate scolloped round the edge, covering tle bottom of the crucible and supported an inch or two above it on proper bearings. ‘The pipe is to closed by a clay plug, externally.” ~ With regard to the losses in working gold ores noted in your article of May 20th, I am confident that in the wet process it occurs from the iatimate pulverization of the contained oresin part, which renders them too light to settle in muddy water; and also from chemical coating on the particles of gold, as well as from their peculiar scaly form, like the finest of mica shivers in appearance. In the dry process I differ with you, and think it chiefly occurs in “sublimatioa ;” for all my experiments in nearly ten years of gold miaing lead me to the conclusion that goldin the floucry state will go wherever quick:ilver does heat. T'o obviate this great waste—from double to three and five times the quantity snived by most mills—as assay of the wnt) eated ores show—I have invented, und am seeking a pntent on a peculiar condensing and purilying apparatus, to be attached to ull furnaces of qnartz mills, which I think will fully overcome this difficulty. Your remark that “the employment of revolving iron eylinders, aud revoiving tables with stirrers have been tried time and ngaiu, aud thrown aside,” is probably truo uf what has been in times past, and your subsequent comment tlnt the “ peculiar arrangement ” of Messrs. C. & I's “cylinder, ete., must be of great valne” for the purposes designe, “if they will stand the attacks of the sulj hur,” f fully coincide with. In one set of my machiuery J have adopted a “revolviug iron table with stirrers,” a3 the very best roasting appnratus for fiuely pulverized ores that could be devised. I enclose it above a circular furuace and cover it with a close jacket, with smoke flue through the centre of jacket, with a daniper therein, thereby economizing the luel and heat, and by means of the stirrers. sceuring au even and thorough roasting at a very low tem-* perature. ‘The ores are admitted near the centre, and pushed off the circumfereuce red hot into a copper vessel of cold water, for purposes belore explained. Warw wir is admitted freely through the discharge sluice, and fresh cold air can be admitted as desired, either at the furuace, passing over the plate aud ores, warm or cold, by side openings, thus securing any qunntity of the much desired oxygen so necessary in the desulphurizing process. For perfect, lasting and rapid pulverizing machines I refer you to the following further extracts from my “ Circular :” «An improvement in the common Stamp Mill, so it caa do work either wet er dry, dry being preterable in these processes in theirdirst stages, viz: Making the dics mortar shaped, rounding the stamps to match, cutting a slot Irom one die or mortar to another half thir depth, placing them ou a descending grade trom the feeding place, so as to compel the ores to pass successively under all the slamps —say from six to twelve in a battery—thus doiug inore than double the work per hour and twice as well as at present under flat stamps. Battery enclosed tight to keep in the dust. “A Pulverizer voceives the crnshed ores from the battery, and passes them through it by gravity, to the roasting furnace. The Pulverizer consists of an irou trough from six to ten inches wide andas inany feet long, sct with a pitch of fifteen to twenty-five degrees, and provided with five or six irou rollers of twelve to sixteen inches diameter, all geared to roll tle ores towards the lower end of the trovgh. ‘The bearings of the rollers hayo springs and sct screws attached, by which ay degree of fincness may be givea to the ores, This machine is covered like the battery.” With regard to smelting the richer mineral ores I will add that the inexhnnstible beds of nitre, soda, alum and sulphur, as ‘vell as galt, so olten fonnd between tle Rocky Mountains and the Sierra Nevada range, ceem to have been specially placed by nature in close proximity with the mineral wealth they are destined at no distaut day to assist in working out of its crude form in the mine, preparatory to its preparation for the use aml conveuience of man What dwellers in this great inineral basin and its mountain ranges need above everything else, at the carliest possible day, is the entire completion of the Pneific Railroad directly through the centre of this great tract, so that the mines can obtain machinery and food at reasonable rates at their homes. Then will the civilized world be utterly astonished at the outpouring of the treasures of American indnstry, from a regioa of country tweaty years ago . thought to be utterly worthless to mankind in general, with, perhaps, a few Humboldt exeeptions. J. A. Arrenines, other metals by the explosive procoss practiced . or can, even uuder the volatilizing pressure of . Denver, Colorado, June 9, 1865.

J a ournal of Aseful Arts, Srienee, nnd a ining and Rlechanical Progress. DEWEY & €O,, PUBRLISREES; -And Patent Sollelioce. b) VOLUMEXI. Number 6, SAN FRANCISCO, SATURDAY, AUGUST 26, 1865. Oo, W. M. suri. DPDEWEY & CO., Publishers. W, B. EWER. 4. T. DEWEY. ——_— Orricr—No, 505 Clay streel, corner of Sansome, 2d floor. ‘Terma of Subseriptions +35 00 Once copy, per annum, In alvance,. macs 0g . AED One copy, xx montha, in wlvanee,. gg For sale by Carriers and Newsdeale Tt is ¥Empnestble for editors to know aut the merits and demerits of their currespondence, conseqnenily the Fender aust not recelve the sully of our contributors ato hn. Intelligent discussion ls invited npou all sides andthe evidence of nny crror which nay wppear will be recelved In friendship aid trcaled with respect. . Amertean and Foreien Patents.—Lelters Patent for Inventorseanbe secured Inthe Uuited States and foreken countries through the MastxG asn Scigstiric Parss Pater Acxyxcy. We oifer apoileants renomable terms, and they enn rest ascured of a strict compllance with our obligations, and a falthful For reference, { perronnnnse of all contrnets. we wii furulsh the names of numerous partles for whom we have obtalned patenie during Ihe past twe yenrs. Pavorable to Tnventors.—Persons holding new Inveutlous of machinery and important Improvements, can have the same Illutirated nnd explalned in lhe Mixine ann Sorxtinio Press, treo of charge, lf In our judgment the discovery Is one of real merfl, and of sutficlent Interest to our renders to warrant publication. Payment in Advance.---Thla paper will not he sent tosubserlbors beyond the lerm pald for. The publishers well know that a good journal cannot be snstalned on the credit system. During the Fair Wo hope the readers of the Mixtna anv Screstiric Prers will look with leniency upon any degression they may obe@rve from the asunl contents and make-np of our journal. Correspondents -will also pleasa hear patlently wilh the erowited slale of our columna la glylug full reporis of the Exhibition. Ork PaprR py Express.—Owing to the fact of Wells Fargo & Co reqniring publishers lo pay 23 cents per copy fn ndyanee oa papers sent to subseribers in the inlerior we are obliged to make our subscription terms by express $6.50 per annum, a Tur Stones or tur Treapre.—The marble stones which composed Solomon’s Temple were said to be forty cubics long twelve thick and eight hich. Suposing a cubic to be eighteen inches, which is the lowest estimate, they would be sixty feet long, cighteen feet thick, and twelve feet high. And supposing n cubic faot of marble to weigh 2,707 ounces, one of these stones weighed 2,752,038 pounds and 12 ounces. And supposing one man to be able to raise 200 pounds, it will require 13,760 nen to raise one of these, and also a little boy who could raise 38 pounds 12 ounces. And suppose ono man to require a square yard to stand upon, it would reqnire 2 acres, 3 roods, 11 perches and 12 yurds for them to stand upon while raising it, besides a place for the little boy to stand. What floats must have been necessary to carry tlicai across the sea to Joppa! And whnt kind of teams, as well us wagoas, do you suppose they had to carry these stones from Joppa to Jerusalem, which is about thirty miles, and a mouatainous country? And what ski!l was necessary to square and dress these immense stones, so that when they were brought together they fitted so exactly that they lad the appearance of being one solid stone. A wave on which many a poor fellow has been carried away is the, wave of a lace-edged cambrie handkerchief. Aut notibility ia its begianings was soniebody’s natural superiority. Tue Richmond Christian Observer is the only religious newspaper now alive iu the Southern States. Perr no faith im a new promise based on th “proved to me that there was a chemical cont(Written tor the Minlag nnd Seientlfic Press. j Colorado Gold Processes. FEoirons Mininé ano Scirntivic Press :— Ina number of your valuable journal, some weeks ago, I noticed an extrnet of a portion of a’ Circular” on some mining processes and machinery that [ issued here about Moreh Ist, 1865, but which was incorrectly copied, so as tu injure its merits. Iu your issuo of May 20th and the week previous, there nre notices of “ Messrs. Crosby & ‘Lhompson’s Process and Machinery.” As theirs and my owu are somewhat similarin parts,and aslam partially acquainted with those gentleincu and their experiments, with your permission I would like to muko some commeuts on their ideas nnd your statements, and some explanations of the points involved in my own inventions, 70 bono publico. You remark of Messrs. C. & ‘T's process, that their assuinption that gold exists in nature as a sulphide, or in a volatile condition, capable of being condensed, “ is without a shadow of proof,” and that “their experiments appear to have been confiued to conceatrated sulphurets, nearly free from quartz.” ‘To this Ianswer, that most of the workable ores in this eonntry arc of that description, eoataining nsually sulphides of gold, silver, copper, and often lead, all mixed together, with fine quartz erystals, aad some quartz unerystalized. In elaborate .experitments on these ores three years ngo, I found in aearly all of them atneral oil, as well as sulphur and arsenie, in quantity, aud other base metals. Ly roasting pulverized ores in a common fire toa red heat, and then plungiug thei red hot into cold water, I separated the copper by precipitation on the bottota of the iron vessel, aad floated off the mineral oil. Iu some instances, where the hcat was at a low red temperature, upon panning down the powdered ore after the above treatment, 1 found the gold in fine scales at the bottom of the pan, and though yellow, yet quicksilver would not tonch them until Ire-heat them with soda or alum, when they lost their yellow hue and amalgamated without difficnlty. Now that ing over the gold in sack pyritous ores that by no process or machinery in use at present, nnless it might be Mr. Crosby's, or those of my own invention, described partially in the accompanying “ Circular,” could the precious metals thereiu contained be saved. So I conclude that inmost of the gold in Colorado ores + but re discovered, exist therein in the state of a sulphide. [We do not see the reason for any such inference, — En. M. aud S. Press.] Yhe silver-lead ores here are much easier treated, but scarcely anything caa be saved froin them by our mills, as they manage thei by the wet process; for the lead, oil and manganese therein fouls up the quicksilver and battery plates ia an hour or two,so that no metal can be caught or saved upon thet, . though these ores are froin. five to ten times as valuable in gold aud silver as the more common guld ores. Ja my experiments oh these I found that roasting them when pulverized with one-tweutieth of soda, by weight, would so soften and decompose thtir constituent particles, that no difficulty was afterward found in grinding gold, silver nnd lead alZ into amalgam . with mercury, and separating the lead [rom the ! breach of an old oue. : in Gerniany, which 1 hud not read or henrd of, Talso found that sulphur Was a great uid in combustion, ond that alum was nearly as good as borax forn Hux ; Inrther nore, that the three used together properly, in but sinall quantities, would flux the must stabboru of these stubborn minerals, and ¢éhese latter ores as freely as desired, precipitatiug all their precious conteuts directly, with but a moderate heat. Tam confident that with a furnace similar to the one described in the following extracts

from uty * Circular,” that thc rich ores of Nevada, ns well as some in this and other sections, ‘cau be made to flow streams of precious inetals, especially with, (and in most iustances without) a hot alr blust. “There is a cluss of ores known as argentiferous galena, which, in addition contain yellow pyrites or sulphates of gold ; these are the richest ores in Colurado, containing often from five to ten dollars per ponud in gold and silver, and a quintity of lead, which has hitherto prevented the collection of the more valuable metals; iu most cases, however, they will yield to the treatment last described; if not, they can be readily jlu.ccd by the following receipe, at an expense of a few cents per round, which is not much when the yield produced thereby is of.en as many dollars : “Totimately mix with the pulverized ores one-tenth to one-twentieth by weight, each, of bi-carbonate or nitrate of soda and rosin ; place the compound in a cone-shaped. boiler-irou or other suitable crucible, and when brought up to a white heat pour into a cavity in the mid-, dle of the masa giinilar aud equal quantities by weight of pulverized borax aud sulphur, ov the same of sulphus and double of alum, which will produce ax dmmediate flux, precipitating the contained metals in a button of more or less parity ; the whole time required being soverucd by the quantity operated on, and the amount of lead in the ores treated.” “The Strelting Furnace designed for the Fluxing Process, is a circnlar stone structure lived with fire-proof Lrick or gneiss, with dome top and tall chinney. It has doors near the buttem for fuel, nnd another opening near the ton of the contained crucible, for the purpose of charging it. ‘fhe crucible may be made of boiler iron in the shape of a sharp cone, and il of large size,is to be provided with oue or more flues throngh its length. It is to be placed vertically in the centre of the furnace, with but a few inches spaco around its rim or larger part ; its top las half-section tron covers, hinged to the rin; a vessel to contain hot water is placed above the crucible, with faucet, to detach slag from the crucible. The crncible has an opeuing in one side, near the bottoin. with curved doors to fit, opening ontward into a square case pussing through the furnace walls to take out the refuse charges through, A curved irsn pipe of nn inch or two in diameter, screwed into or rivited oa the bottom of the crucible, and passing out throuzh the furnace wall serves to draw off the meltcd ores when sufficiently refined, into cold water, or into moulds. ‘The inner opening of the pipe is protecled froin stoppage by a coavex iron plate scolloped round the edge, covering tle bottom of the crucible and supported an inch or two above it on proper bearings. ‘The pipe is to closed by a clay plug, externally.” ~ With regard to the losses in working gold ores noted in your article of May 20th, I am confident that in the wet process it occurs from the iatimate pulverization of the contained oresin part, which renders them too light to settle in muddy water; and also from chemical coating on the particles of gold, as well as from their peculiar scaly form, like the finest of mica shivers in appearance. In the dry process I differ with you, and think it chiefly occurs in “sublimatioa ;” for all my experiments in nearly ten years of gold miaing lead me to the conclusion that goldin the floucry state will go wherever quick:ilver does heat. T'o obviate this great waste—from double to three and five times the quantity snived by most mills—as assay of the wnt) eated ores show—I have invented, und am seeking a pntent on a peculiar condensing and purilying apparatus, to be attached to ull furnaces of qnartz mills, which I think will fully overcome this difficulty. Your remark that “the employment of revolving iron eylinders, aud revoiving tables with stirrers have been tried time and ngaiu, aud thrown aside,” is probably truo uf what has been in times past, and your subsequent comment tlnt the “ peculiar arrangement ” of Messrs. C. & I's “cylinder, ete., must be of great valne” for the purposes designe, “if they will stand the attacks of the sulj hur,” f fully coincide with. In one set of my machiuery J have adopted a “revolviug iron table with stirrers,” a3 the very best roasting appnratus for fiuely pulverized ores that could be devised. I enclose it above a circular furuace and cover it with a close jacket, with smoke flue through the centre of jacket, with a daniper therein, thereby economizing the luel and heat, and by means of the stirrers. sceuring au even and thorough roasting at a very low tem-* perature. ‘The ores are admitted near the centre, and pushed off the circumfereuce red hot into a copper vessel of cold water, for purposes belore explained. Warw wir is admitted freely through the discharge sluice, and fresh cold air can be admitted as desired, either at the furuace, passing over the plate aud ores, warm or cold, by side openings, thus securing any qunntity of the much desired oxygen so necessary in the desulphurizing process. For perfect, lasting and rapid pulverizing machines I refer you to the following further extracts from my “ Circular :” «An improvement in the common Stamp Mill, so it caa do work either wet er dry, dry being preterable in these processes in theirdirst stages, viz: Making the dics mortar shaped, rounding the stamps to match, cutting a slot Irom one die or mortar to another half thir depth, placing them ou a descending grade trom the feeding place, so as to compel the ores to pass successively under all the slamps —say from six to twelve in a battery—thus doiug inore than double the work per hour and twice as well as at present under flat stamps. Battery enclosed tight to keep in the dust. “A Pulverizer voceives the crnshed ores from the battery, and passes them through it by gravity, to the roasting furnace. The Pulverizer consists of an irou trough from six to ten inches wide andas inany feet long, sct with a pitch of fifteen to twenty-five degrees, and provided with five or six irou rollers of twelve to sixteen inches diameter, all geared to roll tle ores towards the lower end of the trovgh. ‘The bearings of the rollers hayo springs and sct screws attached, by which ay degree of fincness may be givea to the ores, This machine is covered like the battery.” With regard to smelting the richer mineral ores I will add that the inexhnnstible beds of nitre, soda, alum and sulphur, as ‘vell as galt, so olten fonnd between tle Rocky Mountains and the Sierra Nevada range, ceem to have been specially placed by nature in close proximity with the mineral wealth they are destined at no distaut day to assist in working out of its crude form in the mine, preparatory to its preparation for the use aml conveuience of man What dwellers in this great inineral basin and its mountain ranges need above everything else, at the carliest possible day, is the entire completion of the Pneific Railroad directly through the centre of this great tract, so that the mines can obtain machinery and food at reasonable rates at their homes. Then will the civilized world be utterly astonished at the outpouring of the treasures of American indnstry, from a regioa of country tweaty years ago . thought to be utterly worthless to mankind in general, with, perhaps, a few Humboldt exeeptions. J. A. Arrenines, other metals by the explosive procoss practiced . or can, even uuder the volatilizing pressure of . Denver, Colorado, June 9, 1865.