Volume 28 (1874) (430 pages)

MINING AND SCIENTIFIC PRESS. {April 11, 1874. W. B. EWER. cece ccc cece ce co ceese cee! SENIOR Enrrok. DEWEY & CO., Publishers. 4. T. DEWEY, GEO. H. BTRONG. WwW. B, EWEE, JNO. L, BOONE. Office, No, 338 Montgomery St., S. E. Corner of balifornia St., diagonally acroes from Wells, Fargo & Co.’s. SunsoRIPTIONS payable in advance—For one year, $4; gix months, $2.26; three months, $1.25. Remittances hy regietered lettere or P. O. orders at our Tiek. ApveEnTiaine Rares.—1 week. lmonth. Smonths. Lyear Per Line..62s+ eens 23 80 $2.00 $5.00 Oue-halfinch. .$1.00 $3.00 $7.50 24.00 One inch... «. 2.00 5.00 14.00 40.00 Large adyertisemente at fayorahle rates. Special or reading notices, legal advertisements, Botices appearing in extraordinary type or in particular parte of the paper, ineerted at epecial rates. Say Francisco: Saturday Morning, April ll. 1874 TABLE OF CONTENTS. GENERAL EDITORIALS. — Knox & Osborn’s Quicksilver Furnace, 225. A True Statesman, 830. YValne of Silyer and Gold; Amalgamation of Bilver Ores; Society of Engineere of California; Native Alloy on the Cometock, 232. Improved Threshing Machine; The Seattle Ooal Mines; Acad. emy of Sciences, 233. The Agaceiz Memorial, 236. ILLUSTRATIONS.—Enox & Oshorn’s Quickeilver Furnace, 225. Charles Sumner, 230, An Improved Threshing Machine, 233. CORRESPONDENCE. — Mining in Plumas and Sierra Oounties—No. 6; Glycerine in Mucilage, 226. SCIENTIFIC PROGRESS. — Sulphuric Acid; The Oxyhydrogen Light; Electrical Art; Wind and Ourrents; Odors, 22'7. MECHANICAL PROGRESS.—The Largest Gun Ever Made; Agricultural Machinery; The Craoston Rock Drill: Peat and Petroleum; Improved Potato Digger, 227. . MINING STOCK MARKET.—Table of Daily Sales and Pricesand Comparative Pricee for the Week; Notices of A it Meeti and Dividend Review of Stock Market forthe Week, 228. MINING SUMMARY from various counties in California and Arizona, 228-9. GOOD HEALTH. -—Meat-Tea; Real and Apparent Waste; Health Maxime from the Apocrypha; Salt for the Throat; Medical Value of Asparagus; Glycerine Placter, 231. USEFUL INFORMATION—Horee-Hair; Burnjog Bricks with Non-Explosive Oil; An Iron Filter; Adulterated Pepper; Salt as a Preservative for Wood; Restoration of Oil Paintinge, 231. MISCELLANEOUS .—Platinum; A Curioeity; The Bladen Mines; Gold on the Yellowstone; Quicksilver, 226. White Pine; Rich Strike; Providing Against Colliesions; Mint Operatione; The Copper Intereste; A Great Feat in Stone Sawing; Arizona Mines; From Pancake, 230. The Gould & Ourry Air-Compressor; Mining in Arizona; Mining Operations in Nevada County; The Highest Monntains; Strange Phenomenon at Gold Hill; The Biggeet Steamship Afloat—America Leade the World, 234, Placer Mining in Colorado; Deceptive Specimens; Inyo County Mines, 236. Rotundity of the Earth. In lookiug over one of that interesting series of pamphlets—‘‘Half-hour Recreations on Popular Science,’’ (Bancroft & Co.,) we came upon an item on the subject referred to, It seems strauge that at the advanced stage of knowledge iu which we now are, that any one ehould have returued to the old belief that the earth was a flat surface. But it seems that at eveu this late day there are some who etill maintain this belief, as will be seen by the item to which we refer, which is as follows: A fruitless attempt hae been made for some years past to induce the helief that the earth is a flat surface; and a Mr. Hampden, who seeme to have beeu persuaded that it is 60, rachly tisked five hundred ponnds on the issue of an experiment on the Bedford Level, in order to test the truth of the assertion. His offer was taken up by Mr. A. R. Wallace, and arraugements satisfactory to Mr. Hampden having been made, the experiment was tried by meane of three dieke, rising forty-two feet ahove the level of tbe surface of a piece of water large enough to show the curvature, if there wero any. Thereferee decided against Mr. Hampden, the central disk rieiug coneiderahly ahove the line formed by the two outer disks, as seen from one end through a selected and approved telesoope. The curvature to and fro iu eix Miles to the extent of about five feet was proved.” A Prospezovs Mine.—‘‘Jefferson’’ writes to ue that the Legal Tender silver mines at Clancey, famous ae the most important silver mines in Moutana, are expected to produce this eeason more than triple the usual quantity of ore. The company have just completed the erection of maohinery and eteam-hoisting apparatus capahle of hoisting 2,800 hucketa in 24 hours. Work inthe main shaft will he immediately commenced, ainking to aud running out two uew levele, both east and west, at a depth of 240 feet and 320 feet. In the 160-foot levele are heavy hreasts of rich ore. The etopes are yielding shipping ore worth $400 per ton. The mining force will prohahly he iucreased to 100 men. Concentrating works are in course oferection, The company have on dump ahout 750 fons of ore preparing to ship to Frieherg, Germany, Coat was last week discovered on the bank of Bear river, Placer county. Amalgamation of Silver Ores. Aaron’s Method as Practiced in Mono County. This method of amalgamation, introduced ahout five years ago, hy C. H. Aaron, is a modification of the Mexican ‘‘fondo,’’ and ia somewhat similar to the ‘‘Ohilian process,”’ descrihed a short time since in the Press. The latter, howsver, in which, according to the desoription, neithsr steam nor metallic copper is used, is not fonnd to answer with the ores of Blind Spring district, whioh cousist in grsat measure of ‘‘Partzite.”” The ore is orushed fine, either wet or dry, and is amalgamated in barrels similar to Frieburg barrels, excspt that steam is intrnduced throngh the journal. From 15 to 40 pounds of sulphate of irou, ahout 50 pounds of salt, aud from two to 10 pounds of iron borings are put with a ton of ore into the harrsl. Also a quantity of copper in the form of halls or small bars. Steam is applied tillthe pulp is boiling hot, and theu the quicksilver is put in. The amalgamation, inclusive of charging aud discharging the harrsls, occupiss from 12 to 24 hours, at the end of which the pulp is passsd to the separators as usual, The object of usiug sulphate of irou is to produce, with the aid of the salt, dichloride of copper from the copper contained iu the ore. The dichloride of copper is the chief agent in this, as iu ths Chilian method, andif there were no Gopner if the ore it would be uecessary touse bluestone. , An improvement, invented and partsnted by Mr. Aaron, consists 10 using a solution of sulphurous acid in water, in place of aulphate of . ¥ iron, by which the dichloride of co},per alone is produced, directly from the ore; while the aulphate of iron produces also protochloride of oopper, which must then be reduced to dichloride at the expense of time and coneumption of the metallic copper and iron turrings. It also injures suoh quicksilver ae remains in the harrel at the time of charging. This improvement is not yet worked on a large scale. The losaof quicksilver, which in the ‘‘fondo”’ is very heavy, it ie claimed is now reduced, hy proper arrangemeut of the settlers, to 174 lbs. per ton of ore. . The results attained by this procese are such as to tax the credulity of the San Franoisco metallurgists, eome of whom decline to helieve that 90 per cent. ie averaged in Mack’s mill at Benton; but we are assured itcan he done. Indeed, Mr. Aaron asserts that he has himself worked rich ore to 97 per cent. of the mint assay, and has averaged 85 per cent. on all-gradee from $70 per ton upwards, with very imperfect means of crushing. . The mill above alluded to crushee the ore dry, throngh a 60-mesh screen, and worke the barrela 24 houre The Pioneer mill at Montgomery crushee dry, through a 40-meah ecreen, worke the barrel 12 houre, and extracts 85 per cent. Formerly thie mill crushed wet iu au arrastra, with results varied from 70 to 97 per ceut. Mr. A. B. Williama ie uow huilding a new mill at Beuton, to work the ore from the Diana mine, and as heisa millman and mechanic, and has had several years experience with thie procees, he will undoubtedly produce firat-class results. If the ore were passed through a screen of 100 meshes to the liuear inch, it is thought that at leact 95 per cent. of the silver could be ohtained from these ores; while the time consumed in workiug them in the barrel would he lesseued. From experiments made some years eince, it appears that the ores of the Comstock vein can be worked to 90 per cent. with great care, hy a elight change in the process, and the bullion would be fiue; but ae the process cannot he worked in pana, there might hesome difficulty in gettiug it adopted, though the inconvenjeuces of barrela will probably eoon be surmounted by a uew machine invented, and about to be tried hy Mr. Aaron, which comhiues the mechanical convenieuce of the iron pan with the chemical possibilities of the wooden harrel. Tue Frexce Gurana Mrves.—Thsse mines, which afew months ago were attracting coneiderable attentiou, have not proved what was expected by the sanguine prospectors, A miner who has returned to Salt Lake City from French Guiana, gives a most discouraging account of hie experience in that conutry. He saye the climate precludes the possihility of successful white labor, and the stories of the richnese of the gold placers are highly overdrawn. It would he a miracle almost fora North Americau to run the gauntlet of the poisonous water and atmosphere of the mining dietrict and come out alive. Most of the Utah party are heartily sick of their venture, and are trying to get hack. We did our best at the time of the excitement to warn miners about the climate of the country and its general unhealthiness, but some men are never contented unless they are looking up uew fields; the further off the better. Tux company orgauized last fall for manufacturiug iron at Ogdeu, will commence huilding inafew daye, and expect to have their works ruuniug by September. Native Alloy on the Comstock. On calling to rsturn a book to our old friend aud correspondent, Mr. Melville Attwood, we fouud him eugaged prepariug some objects for the microscops; aud ou enquiry of what they consisted, he informed us it was the nativs alloy or argsntiferous gold of the Comstock lode. He had devoted much time to the investigation, and made numbsrless assays; and the result was, that he fouud the gold of that great lode ocourrsd in the form ofa native alloy— diffsrent from any he had ever,jheard of—aud was composed of nearly oqual parts of gold and silver. Hs showed ,us epecimens taken from ths lode to the north of Virginia and southward heyond Gold Hill, and from the croppiugs dowu to the deepest workings, all haviug the same character and composition. Mr. Attwood’s researches provs to him that this alloy exists iu all parts, and at all depths of the Comstook, in an unchangsd form. The altoyis fiuely dis. seminatsd in, and intimately mixed with the mineralized silver, having the following charters: hardness, 3; epecific gravity after melting, from 13 571 to 13 7; color, white, with a pale yellowish tinge; aftsr melting, a grayish white, with a shade of yellow; contains 55.37 per csut. of gold, 42.87 of silver, and 1.74 of suhstances as yet undetsrmined. The great difficulty in getting a fair sample of the alloy, was in freeing it from the minsralized silver. In Dana’s Systsm of Mineralogy, page 9, is msntioned an ore named Kustelite, viz: Auriferous Kustelite (1866) coutains from 10 to 30 per cent, of silver; color, whits to pale hrassellow. There is a gradusl passage to ergeutiferous gold. (See gold,) The name Kustelite was given to an ore from Nevada having the following character: H = 2—2'4. 11.32 —18.10; color silver-white, somewhat darker thau native silver on a fresh surface. Richter found init silver, lead aud gold, the first much predominating; from the lode of the Ophir mine, Nevada, in hean-shaped grains. This is so different in character from that now nuder examination, that we think it can hardly he the came. Asit appeare, however, to be named after Mr. Guido Kustel, the ahle metallurgiet of this coast, to whom California and Nevada owe 50 much, Mr. Attwood feels auxious that the alloy should etill hear his name. Mr, Attwood ie indebted to Mr. H. G. Hanks, for assistance rendered iu checking the reeults arrived at in assays, etc. Mr. Hanke is now getting ready a paper for tbe Microscopic Society, describiug the various forms of the mineralized silver found iu the Comstock Lode. Value of Silver and Gold. The basis ypon which the value of silver is oomputed in the U. 8. mint and its branches, is as followe: 99 ounces of pure silver is worth $128 00; or 11 ounces of etaudard silver (900 fiue) is worth $12.80; hence one ounce of pure eilver io worth $1.29.29, and oue ounce of standard eilver is worth $1.16.36. The premium or discount on eilver varies with the eupply and demand. One grain of pure silver is worth $0.0026936; one ouuce Troy of pure eilver is worth $1.292929; ons pound avordupoise of pure silver is worth $18.8547; one ton (2,000 pounds — 29,166.6 ounces Troy) equale $37,709.50; one cubic inch ie worth $7.15; one cubic foot 1s worth $12,355.20. It is presumed that many people do not understand the expreseion of ‘‘finenees’’ in connection with gold aud silver. In speaking of hullion, what we usually call ‘‘finenees’’ is eimply the weight of fine metal contained in a giveu quantity of mixed metals and alloys. For inetance, in a gold or silver bar, which is expected to be 850 fine, it ie simply meant that iu 1,000 parts by weight, 850 are fine gold or jine ailyer, ae the case may be, In our miute the value of gold is computed from standard weight; that ie, gold which is 900 fine, that being the fineness of our gold coiu ae required by law. Of pure gold (1,000 fine) 387 ounces are worth $8,000. Hence one ounce is worth $20.6718334625, and the oue-thousandth part of an ounce, decimally expreseed ae .001 fine, ie worth $0.020671834625. The gold of this State yields on an average 880-thousaudths of the pure metal; that of Auatralia 925-thousandths. ‘This of course varies greatly with the locality. We know of placea only two miles apart where the gold from the upper minea was sold to etorekeepere for $16 per ounce, while that from the lower mines only hrought $11.50 and $12 per ounce. The reacon of this variation in value ie very eimple. The gold from the upper minee coutained very little silver, while that from the lower contained a large proportion of silver, bringing it down invalue according to equal weights. Fine gold 1,000 fine is denominated 24 carata fine. Gold containing two parte of alloy in 24 ie eaid to be 22 carats fine. Jewelry ia generally made of 18 carat gold. MerzornoLooy.—Asa strong argument against the terrihle destructiou of our forests, it hae been predicted that the rainfall would fall off from yearto year. California differs radically in many thinga from our Atlantic States, where thie is an accepted theory. But we were not prepared to see this meteorological law so completely reversed in the Pacific States. This wiuter seems to proclaim that as our forests ! disappear our wiuter rains will increase, Society of Engineers of California. The Socisty of Engineers hsld their first ordinary mseting on Tuesday evening, at the Mechanics’ Institute, Prssidsnt Goorge F. Allardt, C. E., inthe chair, Those pressnt, who had not already signed the rulss of the society, did so, and Mr. Hanscom then read a paper ou the objects and influenos of ths society and the duty of members toward it, which elicited an animated discussion on the many subjects of importance in engineering which should be taken up and ventilated hy the society, Among these are our water supply, harbor proteotion, drainage, roadways, inter-communication by land and water, irrigatiou and kindred subjects of importanose to ths State. The eocisty is a n8w ons and will hs of great benefit to the memhers and the community. Mr. Hanscom's papsr on the ‘ Objects of the Socisty’’ was as follows: . “Jn reading the soisntific and practioal snginesring journals of the day, one may wonder at the rapid strides which hays besn mads in the inoreasiug number of designe and constructions which are at any ous tims hsiug developed and completed. From every quarter of the civilized world we rsad of almost countless projeots in the various hranches of suginsering scisnce which increase in boldness and utility, so that we may almost wonder where will science and skill finally reach. And at the praseut time the various journals are eagerly songht, for almost daily information as to some usw aud grand piecs of construction, or the development of some wonderful design. Eveu the daily newspapers oonsider it important to chroniole in their telegraphic despatchss the progrsss, almost stsp hy stsp, of soms new triumph of learning for the beuefit of humanity. How many sngiueers have watched with the closest attentiou the reports, from week to week, of the construction of the Eact river hridge, from the caissons and their form and strength to resist the pressure of air, through all the various arrangements for placing in positiou—the removal of earth for a proper hed—the appliances for maintaining an atmosphere underneath in which meu could live and work—to the gradual raising of the stoue-work for its cables, which are to constitute one of the arteries of living New York, over which humanity will pulsate daily. There is information for the architect, the hydraulic, and may we add pneumatio engineer, the gas engineer, the mechanicel aud civil engineer, each of itself requiriug the most extensive knowledge and practice in its own particular branch; and I helieve it is a fact that uo eugineering project in the world ie looked upon with so much interest; and why? because from the experience developed iu the construotion of the undertaking. Scientific engineering knowledge ie developed and disseminated in every lace. Ls Thue we see that the grand effort is to obtain knowledge, and that so much the more is information imparted, eo muoh ie the standard of qualification raised among people of all classes and branches of professione., Can we not from this understand that the interohange of ideas, communication of thoughte and theories from study and practice, emulate and insplre us with more effort and intelligence to operate in our varioue positione in life? It is the natural desire for companionship that makes ue agreeable in oompany, and a natural decire for information that makes two of a profession interchange ideas. By our gradual but wonderful means of rapid communication throughout the world we are all becomiug familiar with each other, and by this means are mutually increasing our store of knowledge and daily applyiug new learued priuciples to immediate practice. It ie from such considerations that the effort has heen made to organize and develop the Society of Engineere of California. All acknowledge its necessity and value; and not even those immediately connected with it, hut the community at large. Who does not know the necessity of able and public discussion of the water supply of thie city; or the gas; or the drainage; or railwaye? and do not all commercial men iu the community recognize the importance of protection to our water front? And of no lece imortance ie our communication with each other in the State hy fand aud water. Are not our agriculturiste aware of the vital importance of irrigatiou iu certain portions of our nohle State? All these, and many others of much importauce, are suhjecta on which oue and all desire iuformation; aud here ie the place for each to add hie efforte for the benefit of others, from hie study and experience. It eeems a duty, theu, that we owe each other, to give to all wko may be interested such kuowledge as we may possess, aud can without injury to ourselves. ow often do we in common conversation catch eome new idea, which in some future time develops into a portion of eome work which it seems exactly to fit. Then let each and all endeavor to bring some result of study or practice on hie particular branch for the discussion and benefit of othere, and we chal] have a society which will be of value and honor to ourselves and the community eurrounding wa,” The paper on boiler preesures by Mr. Jamea Spiers wae poetponed on account of illness of the author, until the uext ordinary meeting, which will he held on the first Tuesday in May. Mr. C, H. Louges gave some very iuteresting acoounte of his experieuce in submarine diving in China, iu making examinations of the U. §. steamer Oneida, which was sunk in one hundred and forty feet of water. After which a general discussion took place until ten o’clock, when the meeting adjourued,

MINING AND SCIENTIFIC PRESS. {April 11, 1874. W. B. EWER. cece ccc cece ce co ceese cee! SENIOR Enrrok. DEWEY & CO., Publishers. 4. T. DEWEY, GEO. H. BTRONG. WwW. B, EWEE, JNO. L, BOONE. Office, No, 338 Montgomery St., S. E. Corner of balifornia St., diagonally acroes from Wells, Fargo & Co.’s. SunsoRIPTIONS payable in advance—For one year, $4; gix months, $2.26; three months, $1.25. Remittances hy regietered lettere or P. O. orders at our Tiek. ApveEnTiaine Rares.—1 week. lmonth. Smonths. Lyear Per Line...62s+ eens 23 80 $2.00 $5.00 Oue-halfinch. .$1.00 $3.00 $7.50 24.00 One inch..... «. 2.00 5.00 14.00 40.00 Large adyertisemente at fayorahle rates. Special or reading notices, legal advertisements, Botices appearing in extraordinary type or in particular parte of the paper, ineerted at epecial rates. Say Francisco: Saturday Morning, April ll. 1874 TABLE OF CONTENTS. GENERAL EDITORIALS. — Knox & Osborn’s Quicksilver Furnace, 225. A True Statesman, 830. YValne of Silyer and Gold; Amalgamation of Bilver Ores; Society of Engineere of California; Native Alloy on the Cometock, 232. Improved Threshing Machine; The Seattle Ooal Mines; Acad. emy of Sciences, 233. The Agaceiz Memorial, 236. ILLUSTRATIONS.—Enox & Oshorn’s Quickeilver Furnace, 225. Charles Sumner, 230, An Improved Threshing Machine, 233. CORRESPONDENCE. — Mining in Plumas and Sierra Oounties—No. 6; Glycerine in Mucilage, 226. SCIENTIFIC PROGRESS. — Sulphuric Acid; The Oxyhydrogen Light; Electrical Art; Wind and Ourrents; Odors, 22'7. MECHANICAL PROGRESS.—The Largest Gun Ever Made; Agricultural Machinery; The Craoston Rock Drill: Peat and Petroleum; Improved Potato Digger, 227. . MINING STOCK MARKET.—Table of Daily Sales and Pricesand Comparative Pricee for the Week; Notices of A it Meeti and Dividend Review of Stock Market forthe Week, 228. MINING SUMMARY from various counties in California and Arizona, 228-9. GOOD HEALTH. -—Meat-Tea; Real and Apparent Waste; Health Maxime from the Apocrypha; Salt for the Throat; Medical Value of Asparagus; Glycerine Placter, 231. USEFUL INFORMATION—Horee-Hair; Burnjog Bricks with Non-Explosive Oil; An Iron Filter; Adulterated Pepper; Salt as a Preservative for Wood; Restoration of Oil Paintinge, 231. MISCELLANEOUS .—Platinum; A Curioeity; The Bladen Mines; Gold on the Yellowstone; Quicksilver, 226. White Pine; Rich Strike; Providing Against Colliesions; Mint Operatione; The Copper Intereste; A Great Feat in Stone Sawing; Arizona Mines; From Pancake, 230. The Gould & Ourry Air-Compressor; Mining in Arizona; Mining Operations in Nevada County; The Highest Monntains; Strange Phenomenon at Gold Hill; The Biggeet Steamship Afloat—America Leade the World, 234, Placer Mining in Colorado; Deceptive Specimens; Inyo County Mines, 236. Rotundity of the Earth. In lookiug over one of that interesting series of pamphlets—‘‘Half-hour Recreations on Popular Science,’’ (Bancroft & Co.,) we came upon an item on the subject referred to, It seems strauge that at the advanced stage of knowledge iu which we now are, that any one ehould have returued to the old belief that the earth was a flat surface. But it seems that at eveu this late day there are some who etill maintain this belief, as will be seen by the item to which we refer, which is as follows: A fruitless attempt hae been made for some years past to induce the helief that the earth is a flat surface; and a Mr. Hampden, who seeme to have beeu persuaded that it is 60, rachly tisked five hundred ponnds on the issue of an experiment on the Bedford Level, in order to test the truth of the assertion. His offer was taken up by Mr. A. R. Wallace, and arraugements satisfactory to Mr. Hampden having been made, the experiment was tried by meane of three dieke, rising forty-two feet ahove the level of tbe surface of a piece of water large enough to show the curvature, if there wero any. Thereferee decided against Mr. Hampden, the central disk rieiug coneiderahly ahove the line formed by the two outer disks, as seen from one end through a selected and approved telesoope. The curvature to and fro iu eix Miles to the extent of about five feet was proved.” A Prospezovs Mine.—‘‘Jefferson’’ writes to ue that the Legal Tender silver mines at Clancey, famous ae the most important silver mines in Moutana, are expected to produce this eeason more than triple the usual quantity of ore. The company have just completed the erection of maohinery and eteam-hoisting apparatus capahle of hoisting 2,800 hucketa in 24 hours. Work inthe main shaft will he immediately commenced, ainking to aud running out two uew levele, both east and west, at a depth of 240 feet and 320 feet. In the 160-foot levele are heavy hreasts of rich ore. The etopes are yielding shipping ore worth $400 per ton. The mining force will prohahly he iucreased to 100 men. Concentrating works are in course oferection, The company have on dump ahout 750 fons of ore preparing to ship to Frieherg, Germany, Coat was last week discovered on the bank of Bear river, Placer county. Amalgamation of Silver Ores. Aaron’s Method as Practiced in Mono County. This method of amalgamation, introduced ahout five years ago, hy C. H. Aaron, is a modification of the Mexican ‘‘fondo,’’ and ia somewhat similar to the ‘‘Ohilian process,”’ descrihed a short time since in the Press. The latter, howsver, in which, according to the desoription, neithsr steam nor metallic copper is used, is not fonnd to answer with the ores of Blind Spring district, whioh cousist in grsat measure of ‘‘Partzite.”” The ore is orushed fine, either wet or dry, and is amalgamated in barrels similar to Frieburg barrels, excspt that steam is intrnduced throngh the journal. From 15 to 40 pounds of sulphate of irou, ahout 50 pounds of salt, aud from two to 10 pounds of iron borings are put with a ton of ore into the harrsl. Also a quantity of copper in the form of halls or small bars. Steam is applied tillthe pulp is boiling hot, and theu the quicksilver is put in. The amalgamation, inclusive of charging aud discharging the harrsls, occupiss from 12 to 24 hours, at the end of which the pulp is passsd to the separators as usual, The object of usiug sulphate of irou is to produce, with the aid of the salt, dichloride of copper from the copper contained iu the ore. The dichloride of copper is the chief agent in this, as iu ths Chilian method, andif there were no Gopner if the ore it would be uecessary touse bluestone. , An improvement, invented and partsnted by Mr. Aaron, consists 10 using a solution of sulphurous acid in water, in place of aulphate of . ¥ iron, by which the dichloride of co},per alone is produced, directly from the ore; while the aulphate of iron produces also protochloride of oopper, which must then be reduced to dichloride at the expense of time and coneumption of the metallic copper and iron turrings. It also injures suoh quicksilver ae remains in the harrel at the time of charging. This improvement is not yet worked on a large scale. The losaof quicksilver, which in the ‘‘fondo”’ is very heavy, it ie claimed is now reduced, hy proper arrangemeut of the settlers, to 174 lbs. per ton of ore. . The results attained by this procese are such as to tax the credulity of the San Franoisco metallurgists, eome of whom decline to helieve that 90 per cent. ie averaged in Mack’s mill at Benton; but we are assured itcan he done. Indeed, Mr. Aaron asserts that he has himself worked rich ore to 97 per cent. of the mint assay, and has averaged 85 per cent. on all-gradee from $70 per ton upwards, with very imperfect means of crushing. . The mill above alluded to crushee the ore dry, throngh a 60-mesh screen, and worke the barrela 24 houre The Pioneer mill at Montgomery crushee dry, through a 40-meah ecreen, worke the barrel 12 houre, and extracts 85 per cent. Formerly thie mill crushed wet iu au arrastra, with results varied from 70 to 97 per ceut. Mr. A. B. Williama ie uow huilding a new mill at Beuton, to work the ore from the Diana mine, and as heisa millman and mechanic, and has had several years experience with thie procees, he will undoubtedly produce firat-class results. If the ore were passed through a screen of 100 meshes to the liuear inch, it is thought that at leact 95 per cent. of the silver could be ohtained from these ores; while the time consumed in workiug them in the barrel would he lesseued. From experiments made some years eince, it appears that the ores of the Comstock vein can be worked to 90 per cent. with great care, hy a elight change in the process, and the bullion would be fiue; but ae the process cannot he worked in pana, there might hesome difficulty in gettiug it adopted, though the inconvenjeuces of barrela will probably eoon be surmounted by a uew machine invented, and about to be tried hy Mr. Aaron, which comhiues the mechanical convenieuce of the iron pan with the chemical possibilities of the wooden harrel. Tue Frexce Gurana Mrves.—Thsse mines, which afew months ago were attracting coneiderable attentiou, have not proved what was expected by the sanguine prospectors, A miner who has returned to Salt Lake City from French Guiana, gives a most discouraging account of hie experience in that conutry. He saye the climate precludes the possihility of successful white labor, and the stories of the richnese of the gold placers are highly overdrawn. It would he a miracle almost fora North Americau to run the gauntlet of the poisonous water and atmosphere of the mining dietrict and come out alive. Most of the Utah party are heartily sick of their venture, and are trying to get hack. We did our best at the time of the excitement to warn miners about the climate of the country and its general unhealthiness, but some men are never contented unless they are looking up uew fields; the further off the better. Tux company orgauized last fall for manufacturiug iron at Ogdeu, will commence huilding inafew daye, and expect to have their works ruuniug by September. Native Alloy on the Comstock. On calling to rsturn a book to our old friend

aud correspondent, Mr. Melville Attwood, we fouud him eugaged prepariug some objects for the microscops; aud ou enquiry of what they consisted, he informed us it was the nativs alloy or argsntiferous gold of the Comstock lode. He had devoted much time to the investigation, and made numbsrless assays; and the result was, that he fouud the gold of that great lode ocourrsd in the form ofa native alloy— diffsrent from any he had ever,jheard of—aud was composed of nearly oqual parts of gold and silver. Hs showed ,us epecimens taken from ths lode to the north of Virginia and southward heyond Gold Hill, and from the croppiugs dowu to the deepest workings, all haviug the same character and composition. Mr. Attwood’s researches provs to him that this alloy exists iu all parts, and at all depths of the Comstook, in an unchangsd form. The altoyis fiuely dis. seminatsd in, and intimately mixed with the mineralized silver, having the following charters: hardness, 3; epecific gravity after melting, from 13 571 to 13 7; color, white, with a pale yellowish tinge; aftsr melting, a grayish white, with a shade of yellow; contains 55.37 per csut. of gold, 42.87 of silver, and 1.74 of suhstances as yet undetsrmined. The great difficulty in getting a fair sample of the alloy, was in freeing it from the minsralized silver. In Dana’s Systsm of Mineralogy, page 9, is msntioned an ore named Kustelite, viz: Auriferous Kustelite (1866) coutains from 10 to 30 per cent, of silver; color, whits to pale hrassellow. There is a gradusl passage to ergeutiferous gold. (See gold,) The name Kustelite was given to an ore from Nevada having the following character: H = 2—2'4. 11.32 —18.10; color silver-white, somewhat darker thau native silver on a fresh surface. Richter found init silver, lead aud gold, the first much predominating; from the lode of the Ophir mine, Nevada, in hean-shaped grains. This is so different in character from that now nuder examination, that we think it can hardly he the came. Asit appeare, however, to be named after Mr. Guido Kustel, the ahle metallurgiet of this coast, to whom California and Nevada owe 50 much, Mr. Attwood feels auxious that the alloy should etill hear his name. Mr, Attwood ie indebted to Mr. H. G. Hanks, for assistance rendered iu checking the reeults arrived at in assays, etc. Mr. Hanke is now getting ready a paper for tbe Microscopic Society, describiug the various forms of the mineralized silver found iu the Comstock Lode. Value of Silver and Gold. The basis ypon which the value of silver is oomputed in the U. 8. mint and its branches, is as followe: 99 ounces of pure silver is worth $128 00; or 11 ounces of etaudard silver (900 fiue) is worth $12.80; hence one ounce of pure eilver io worth $1.29.29, and oue ounce of standard eilver is worth $1.16.36. The premium or discount on eilver varies with the eupply and demand. One grain of pure silver is worth $0.0026936; one ouuce Troy of pure eilver is worth $1.292929; ons pound avordupoise of pure silver is worth $18.8547; one ton (2,000 pounds — 29,166.6 ounces Troy) equale $37,709.50; one cubic inch ie worth $7.15; one cubic foot 1s worth $12,355.20. It is presumed that many people do not understand the expreseion of ‘‘finenees’’ in connection with gold aud silver. In speaking of hullion, what we usually call ‘‘finenees’’ is eimply the weight of fine metal contained in a giveu quantity of mixed metals and alloys. For inetance, in a gold or silver bar, which is expected to be 850 fine, it ie simply meant that iu 1,000 parts by weight, 850 are fine gold or jine ailyer, ae the case may be, In our miute the value of gold is computed from standard weight; that ie, gold which is 900 fine, that being the fineness of our gold coiu ae required by law. Of pure gold (1,000 fine) 387 ounces are worth $8,000. Hence one ounce is worth $20.6718334625, and the oue-thousandth part of an ounce, decimally expreseed ae .001 fine, ie worth $0.020671834625. The gold of this State yields on an average 880-thousaudths of the pure metal; that of Auatralia 925-thousandths. ‘This of course varies greatly with the locality. We know of placea only two miles apart where the gold from the upper minea was sold to etorekeepere for $16 per ounce, while that from the lower mines only hrought $11.50 and $12 per ounce. The reacon of this variation in value ie very eimple. The gold from the upper minee coutained very little silver, while that from the lower contained a large proportion of silver, bringing it down invalue according to equal weights. Fine gold 1,000 fine is denominated 24 carata fine. Gold containing two parte of alloy in 24 ie eaid to be 22 carats fine. Jewelry ia generally made of 18 carat gold. MerzornoLooy.—Asa strong argument against the terrihle destructiou of our forests, it hae been predicted that the rainfall would fall off from yearto year. California differs radically in many thinga from our Atlantic States, where thie is an accepted theory. But we were not prepared to see this meteorological law so completely reversed in the Pacific States. This wiuter seems to proclaim that as our forests ! disappear our wiuter rains will increase, Society of Engineers of California. The Socisty of Engineers hsld their first ordinary mseting on Tuesday evening, at the Mechanics’ Institute, Prssidsnt Goorge F. Allardt, C. E., inthe chair, Those pressnt, who had not already signed the rulss of the society, did so, and Mr. Hanscom then read a paper ou the objects and influenos of ths society and the duty of members toward it, which elicited an animated discussion on the many subjects of importance in engineering which should be taken up and ventilated hy the society, Among these are our water supply, harbor proteotion, drainage, roadways, inter-communication by land and water, irrigatiou and kindred subjects of importanose to ths State. The eocisty is a n8w ons and will hs of great benefit to the memhers and the community. Mr. Hanscom's papsr on the ‘ Objects of the Socisty’’ was as follows: . “Jn reading the soisntific and practioal snginesring journals of the day, one may wonder at the rapid strides which hays besn mads in the inoreasiug number of designe and constructions which are at any ous tims hsiug developed and completed. From every quarter of the civilized world we rsad of almost countless projeots in the various hranches of suginsering scisnce which increase in boldness and utility, so that we may almost wonder where will science and skill finally reach. And at the praseut time the various journals are eagerly songht, for almost daily information as to some usw aud grand piecs of construction, or the development of some wonderful design. Eveu the daily newspapers oonsider it important to chroniole in their telegraphic despatchss the progrsss, almost stsp hy stsp, of soms new triumph of learning for the beuefit of humanity. How many sngiueers have watched with the closest attentiou the reports, from week to week, of the construction of the Eact river hridge, from the caissons and their form and strength to resist the pressure of air, through all the various arrangements for placing in positiou—the removal of earth for a proper hed—the appliances for maintaining an atmosphere underneath in which meu could live and work—to the gradual raising of the stoue-work for its cables, which are to constitute one of the arteries of living New York, over which humanity will pulsate daily. There is information for the architect, the hydraulic, and may we add pneumatio engineer, the gas engineer, the mechanicel aud civil engineer, each of itself requiriug the most extensive knowledge and practice in its own particular branch; and I helieve it is a fact that uo eugineering project in the world ie looked upon with so much interest; and why? because from the experience developed iu the construotion of the undertaking. Scientific engineering knowledge ie developed and disseminated in every lace. Ls Thue we see that the grand effort is to obtain knowledge, and that so much the more is information imparted, eo muoh ie the standard of qualification raised among people of all classes and branches of professione., Can we not from this understand that the interohange of ideas, communication of thoughte and theories from study and practice, emulate and insplre us with more effort and intelligence to operate in our varioue positione in life? It is the natural desire for companionship that makes ue agreeable in oompany, and a natural decire for information that makes two of a profession interchange ideas. By our gradual but wonderful means of rapid communication throughout the world we are all becomiug familiar with each other, and by this means are mutually increasing our store of knowledge and daily applyiug new learued priuciples to immediate practice. It ie from such considerations that the effort has heen made to organize and develop the Society of Engineere of California. All acknowledge its necessity and value; and not even those immediately connected with it, hut the community at large. Who does not know the necessity of able and public discussion of the water supply of thie city; or the gas; or the drainage; or railwaye? and do not all commercial men iu the community recognize the importance of protection to our water front? And of no lece imortance ie our communication with each other in the State hy fand aud water. Are not our agriculturiste aware of the vital importance of irrigatiou iu certain portions of our nohle State? All these, and many others of much importauce, are suhjecta on which oue and all desire iuformation; aud here ie the place for each to add hie efforte for the benefit of others, from hie study and experience. It eeems a duty, theu, that we owe each other, to give to all wko may be interested such kuowledge as we may possess, aud can without injury to ourselves. ow often do we in common conversation catch eome new idea, which in some future time develops into a portion of eome work which it seems exactly to fit. Then let each and all endeavor to bring some result of study or practice on hie particular branch for the discussion and benefit of othere, and we chal] have a society which will be of value and honor to ourselves and the community eurrounding wa,” The paper on boiler preesures by Mr. Jamea Spiers wae poetponed on account of illness of the author, until the uext ordinary meeting, which will he held on the first Tuesday in May. Mr. C, H. Louges gave some very iuteresting acoounte of his experieuce in submarine diving in China, iu making examinations of the U. §. steamer Oneida, which was sunk in one hundred and forty feet of water. After which a general discussion took place until ten o’clock, when the meeting adjourued,