Volume 29 (1874) (428 pages)

. MINING. AND SCIENTIFIC -PRESS. [September 12, 1874. W. B, EWER.:.-0+0 ++. SENIOR EDITOR, DEWEY & Co., Publishers. A, T. NEWEY, ss GEO, H. STRONG. W. B. EWER, INO. Li. BOONE. Office, No. 224 Sansome St., 8S. E. Cnrner nf California St., San Franciscn. SuBeoRnwr0Ne payahle in advance—For one year, $4; Six months, $2.25; three monthe, $1.25. Remittances hy registered iotters or P. O. orders at our risk. ANVEERTISING RaTES.—1 week. 1month. 3months, 1 year Per line. 25 80 $2.00 $5.00 One-haif . $3.00 $7.50 24.00 One inch. 2 5.00 14.00 40.00 Large advertisements at favorahle rates. Special or reading notices, legal adver ti ti 53) ng in extraordinary type or in particular parts of the paper, inserted at special rates. San Francisco: Saturday Morning, Sept. 12, 1874. TABLE OF CONTENTS, GENERAL EDITORIALS. — The Old Soggs Mine; Mending Cracked Belle; Tripartite Chain Connector, 161. Casting a Patch: New Procees of Working Black Sand; Discovery of Sapphires; Central Pacific Hoepital; Class Exhihit—9th Induetrial Exhihition, 168. Leffel's Donhle Turhine Wheele, 169. Obromium; Academy of Sciences; Patents and Inventions, 172. ILLUSTRATIONS.—Quinian’s Chain Connector; Device for Mending Sroken Beile, 161. Leffel’s Im. proved Patent Globe Casing, 169. SCIENTIFIC PROGRESS. — Vegetation Inside an Egg: Light and Electricity; Hydrium; the Siphon; Thermometers; Yellow Glass for Photographic Purpoees; The Microxcopic Examiration of Well Water; Wilt it Work? Manufactnre of Gun Cotton, 168. MECHANICAL PROGRESS.—The Firat Tool Used hy Man; Aero-Steam Enginee; Iron Clad Vessela: Economy of Iron Cars; How Thimbles are Made; Europesn Crdnance; Double Chronometer Bank Lock, 163. MINING STOCK MARKET.—Table of Daily Sates and Prices and’Comparative Prices for the Week; Notices of Aseessments; Meetings and Dividends; Review of Stock Market for the Week, 164. MINING SUMMARY from various counties in Oalifornis and Nevada, 164-165-172. GOOD HEALTH. —Engiish Food Adulteration; Cautione Concerning the Use of Paris Green; Dog Dentistry; The Eyes ang Spectacles; Middle Age; Byes and Cold Water; Obesity and Hezith; The Teeth, 167. USEFUL INFORMATION. — Building Housee; Gilding and Siivering Silk Thread; Urnamentation of Giass; How to Make a Good Bed; Plate Polishing Powder; Test of Steei: Curriage Springe: Rawhide Journals; To Take Stains out of Ivory, 167.MISCELLANEOUS. — Indusiriat Fairs —Exhihitione of the Mechanics’ Institute; The Sonora Company; Smatl Business; Quartz Mines of Washington and Eureka; Loading Hay, 162. Machinery at the Fair; Prospect for Ciliformia Tohacco; Sorghum; Tellurets; Revival of Sineltiug at White Pine; The Howiand Tunnei; The Rye Valley Mines; Important to Inventors; From Tyho, 166. Wore of the Black Bear Company; The Mines at Bennock; Petroieum in Ventnra County: Tue New Boulder Ditch; Is Mining a Legitimate Businese? New Mill; Mining vs. Farming; A New Fume Arrester; Troy District; Gone Proepecting, 170. THE-Village of Yon Bet, situated abont eix miles northeast of Nevada city, was destroyed by fire on Wednesday last. The place contained bnt few business honses, which were totally coneumed, save Fox & Oliver’s store, and an old nnocenpied building. Tux Inter-State Induetrial Exhibition opened in Chicago on the 9th inst. Itis in every particular far superior to the exhibition of last year, since all the departments are mere complete and the decorations and fixtnres much handsomer. American InstituTE.—The fourth annual exhibition of the American Institute was formally opened in New York, on the 9th inst. The display in all departments is said to be more varied aud extensive than in former years. THE mills near Dayton are working to their full capacity, some on tailings, and others on nre from the Belcher and other Comstock minee. A large quantity of wood is piled upon the banks of the river, ready for shipment to Gold Hill and Virginia, Jamzs Connery, chief of the boiler depariment of the Baldwin Locomotive Works, has invented a new eystem of caulking boiler seams, and a naval commission has been ordered to examine and report upon its merits, It is rnmored that engineere are out to locate the line of the Southern Pacific railroad from Bukersfield to San Fernando, and that the company will soon oommence active operations in the way of road building. TuHE process of refining ie now in full blast at the smelting works at Sacramento, employing eome 20 men night and day. Smelting will be resumed at these works as soon as the new furaces are complete, which will be in a few daye. Cres. JOHNSON discovered 2 lead of stonecoal about 28 miles south of Eugene city, on the East Fork of the Willamette, one day last week. The outcroppings indicate a rich depoeit. 2 H. B. Puatr, the lessee of tbe coal mines near Tone oity, will ship 500 tons to Stockton immediately. The vein is 10 feet thick and constantly improving, A New Process of Working Biack Sand. We have received several letters of inquiry in relation to the process and machinery employed by the Perseverance Black Sand mining compsny to amalgamate the infiuitesimal particles of gold and separate’ the fine or floured quicksiiver from the black sand, which was noticed in this paper some weeks since. The President of the compsny has furnished ns . with the leading features of the process, which will enable those acqnainted with such matters to judge of its merits, The sand is first screened so as to materially reduce its bulk, and then snbjected for about twenty-four hours to 2a solution composed of canstio potash and common selt in proper quantities. This is for the purpose of remoying any coating or oxide that may be upon the gold, and destroying sulphur and other base substances which would be absorbed by the quicksilver. to its injury. The pulp is then hea’edin a pan bya jet of steam (being constantly stirred), which takes but a few minutes, as it should not be too hot, and then the quicksilver is poured in and the steam and agitation continued from fifteen to thiity minutes, when the gold becomes thoroughly amulgamated, and the pulpis discharged into a vat to cool before putting it throngh the separaling sluice. The heat has the effect of expanding or partially vaporizing the qnicksilver, and, aided by the agitation, distributes itall through the sand pulp iu very fine particles, like flour, where it meets and amatgumates with the equally flue and universally diffused particles of gold. Care must be exercised in the heating, ae too much heat flonrs the qnicksilver moie than is necessary to secure pertect amalgamation, and tbereby increasee the difficnity of collecting it. together again withont serious lose. When we consider the faotthat the amount of hext required to raise the temperatnre of one pound of water from 32° to 212° will raise that of about 30 pounds of qnicksilver throngh the same range, the reason for thie cantion is obvione. There is reason to believe that most of our millmen have fallen into the common error of nsing too much heat in amalgamating the precions metals. It is proper to state here that great oare is taken to purify the quicksilver, by proper means, before it is pnt into the puln, upon every occasion of nsing it, as euccees depends much upon having the quicksilver in good condition. Retorting alone ie not always sufficient, as some of the base metals volatilize and pass over with the mercurial vapor. The last and most difficult operation is that of sep :rating the fine particles of smalgam and quicksilver from the heavy black sand, and collecting them together again without too great loss; for it mnst be remembered that black sand cannot be treated like quartz pulp, on account of its greater sprcific gravity. The fine particles of gold and qnickeiiver cannot be wholly precipitated by agitation or a ec .ncentcating motion, because they are so minnte and light in comperison to the grains of sand, that they will not settle by their own gravity through the heavy sand, as through qnariz nlp. B This difficulty is overcome and separation secured without material loss, by this company, by means of a systeni of palvanized copper roliere, grooved spirally, and placed side by side and in layers one above the other, so asto “break joints’’ and not qnite touoh together, and extending across the sluice, which is three feet or more in width. A soreen is placed over them to distribute the sand and water as they fall upon them, and a galvanized eopper plate beneath to catch the qnicksilver asit dripsfrom them. Two or three layers of these rollers are thus arranged at two or more places a few feet apart in the sluice, and drop tiffleeor wells are sunk across the bottom a little below the copper plates, to receive and retain the quicksilver as it runs off fromthem. The rollere are one foot in length, »nd one and a half iuches in diameter and hollow, six or eight of which are lnid side by side und end to end extending across the width of the sluice. These, as also the copper plates, are kept in a highly sensitized condition and tree from verdigris, andas the pulp passes down over and between their multiplied surfaces it necessarily brings the fine particles of quickeilver into contact with some one of them to which they will adhere, before passiug through the whole of them as arrangedin the sluice. Ae the quicksilver accumulates upon the rollers it drops from the under side, and the amalgam is cleaned from them in the same,manner es from the platee. Theee amalgamating rollers and their application to both the cradle and the sluice, are the invention of William Subl:tt of this city, who has applied for a parent therefor, and have been frecly tested by the Perseverance company, who areabout to employ them in exteneive operations in black sund mining at the month of Rogue river, where they have valnable claims. Now that a practical method of treating the auriferous beach sands of onr nortbern coast appears to have been found, we hear of other parties about to engage in this class of mining, which promises to attract great attention another season, J. McM. Suarrer will deliver the annual address before the Sonoma and Marin Agricnltnral society this yoar. Discovery of Sapphires. Discoveries of varions kinds of minerals and precious stones have been made lately in the United States of Colombia, and that country will before long take a fair. place among the mineral-producing regions of the globe. ‘The placer mines in varions States are now yielding considerable gold, since the hydraulic process in vogue in this State is now extensively used there. Several American and English companies are working the hydraulic mines, and some of them are doing very well. in a conversa ion this week wilh Mr. Morales, Colombian Cousul at this port, he told us that severs] sapphires had recently been fouud in the State of Cauca. They were brought here by Dr. Weaver, and the man who found them told the doctor that there were many of these stones there. The lapidaries to whom the stones were shown pronounced them sapphires and-valuable, but not of the right color to be very valuable. They thiuk, however, that if further search is made, sapphires of proper color to he of value will be found. These stones, which we examined, are a little too clear and light colored to be handsome. The two larger ones shown us would have been worth $500 each, if of a deeper color. One of ahout half the size, the lapidaties pronounced worth $50, even with th: off color; 60 the find is a g 10d one, after all. The stonés were fouod accidentally on the surface, and tho ground will probably now be worked deeper, to eee if darker colored eapphires cannot be found. The man who found them was not aware of their real value, nor wae Dr, Weaver until they had been examined by the lapidaries. The eapphires were fonnd in the Stute of Cauca, on the interior side from the western range of the Andes, They are genuine sapphires, but not of the proper color 10 minke them very valuahle. The stones are quite lirze, and will ehortly be cut and set. Sapphires are next in hardnese to diamonds. They are found in various colore, and are much admired, heing of value according to the tints of the stone. The Central Pacific Hospital. The Central Pacific Railroad Co., that much abnsed corporation and ‘‘soulless monopoly,” ought to have more credit than it receives for some things it doee. For instance, the company hae a five hospital at Sacramento for the accummodation of the employees of the railruad, as well as for strangers who are hurt on the road. Half the time the passengers are injured by their own carlessness, or by non-compliance with ihe rulee of the company; nevertheless, they ure taken in and cared ior in the best manner possible hy the Coeutral Pacific people. The hospital is situated on G street, andthe building is sufficiently largo for the p.tients now tbere, andformauy more. There is an air of comfortubout the place not usually met with in public hoxpitals. There are no loug faces, no pititul compluiuts, and every want is met by skilltul attéudants, The library is particularly worthy of mention, and no doubt most of the convalescents bless the liberality of a company which providee for the comforte as well as the necessariee of life in such a place. The ventilation of the building, the arrangemeutsand style of beds, surgical appliances, the kitchen, dining rooms, étc., all evince skill and jndgment. The grounds are neatly laid out, and the place generally is comfort thle, olean and pleasant. Mr. Forbes, the steward, attends faithfully to hie duties, and the whole hospital is exceliently managed, furnishing a pattern which others might follow with benefit. Tue fifth anunal exhibition of Moutana, under the atispices of the Agricultural, Mineral and Mechanical Association, commences on the Territorial fair grounds, near Helena, on the 14th inst, A BAR of pure gold, weighing 312 ounces, was the result of eight days’ run of an 8-stamp mill on quartz from the Cabell ledge, in Baker conuty, Oregon. THE Virginia and Truckee railrond company will introduce the Westinghouee patent air brakes on their passenger coaches ut un early day. Tue Gilroy Consolidated Cigar Factory manufactured 200,000, and shipped 250,000 cigars for the month of August. Tue Lyou county Times reports the discove ot about 200 acres of mineral coal land in El Dorado canton. Tue Eureka mill, Carson river, worked about 6,000 tons of ore Jast month. This is the biggest run by the mull. THERE are six wagon-making establishments in Petaluma, and all are busily employed at present. . Tue water in Carson river is now very low and irregular in its flow. A bust of 700 ponnds of powder was put off in the American mine, at San Jun, on Saturday. THE Creed & Rutler mine, iu Co!orado, was recently sold to a Holland company for #3,000,~000. . Class Exhibit—9th Industrial Exhibition, Prime Movers—Water Wheels. In our ennmeration and notices of prime movers, we inadvertently overlooked ‘‘waterwheels,’’ of which there are two exhibitors. Motive machines, as steam engines, water wheels and windmills are simply contrivances: interposed between the power—the steamboiler, the waterfall or the wind—and the work to be done, Their form and combination of mechanical principles is supposed to comprise the most economio and convenient means for taking up the power at d sposil and conveying it.to the various appliances for perfurming the work required. Thus in the use of water there are various classes of wheels termed overshot, breast, undershot and turbine wheels, according to tbe manner in which the water is bronght upon them. In calenlating the power of a water wheel we multiply the weight of water by the hight throngh which it falls. Thus: 500 cubio feet of water (which weighe 30,000 pounds), falling through one foot of hight in aminute, represents, conventionally, onehorse power; 50U cnbie feet falliog through ten feet per minute, represents ten-horse power; 10v0 cubic fret falling through four feet per munnte repreeents eight-hor-e power, etc. In any water wheel the puwer actually obtained from the water passing throngh it ie only a certain proportion of the caloulated power, from the faot that much power is loet by the shocks und changes of velocity which it experiences ou entering und leaving tbe wheel, and by the friction on thejounate uf the same; aleo inthe furm of the buckets, the general conetrnction of the wheel, tbe fasteniug of the aims, the axle, etc. In prac ioal use the losses alising from the differeut torms of wheels are substantially about as tollows: In the best turbines, trom 15 to 20 per cent.; in indifferent turbiues, 25 to 40 per cent.; in overshot wuee!s, 30 tu 40 per cent.; in breast wheels, 40 to 45 per cent.; in the best uudershot wheela— hurdy-gurdies with light work—50 per cent., and 1rom 60 to 70 in others. From this it will be seen that the turbine is the most effective form uf water-wheel in nse. iis compact torm and small liability to get out of order, and ready adjuetmeut for work, are also impuitant advautayes connected with its nse. Lhere are hut two exhibitors of water wheels in the Pavilion, hoth of whom exh bit tnrhine wheels only. Mr. Myers exhibits tive of L ftel & Myers’ untbiue wheels, all of large, working dimengions; aud Baker & Hamilton exhibit a smi mudel of the Ecl.p-e Double Lu. bine. The turbine wheel was intrudnced into Europe abont foity yeurs ago, and from theuce to the United States ahout ten years later. It was fir-t known here asthe Paiker Turbine wheel, a moditicaion of the European Joinville. A turbine wheel differs «sentially from avy other in receiving and dircharging water in wil directlons around its axis; and in the fuither fact that it losce but & mere moiety of efficiency when snbmerged. ‘lhe modilcations of this wheel are very nnmerous; not less than oue hundred and twenty-five patents on such modificatiuns have been taken out in this country alone within the last ten years. The Leffel wheel shown hy Mr. Myets seems to have distanced all cumpetitors iu the reputation which it has secured, and in the numberein use. Over 3,000 are now in use in the United Statee, of which 300 are enumerated in California and Oregon, and abont 100in Utah. It is employed here for all sorte of work, as for runnivg quaitz milis, flour mills, woolen mills, saw miils, ete. It is constructed of varioue dimensions, from three or four horse-power up to turee or fuur hundred horse-power. One of these wheelsis the only power employed in driving the largest quartz mill on this coaet— tuat of the Union Mill Company, on the Carson river, This mill—a double Leffel turbine—ig only 52 inches in diameter, and 1s placed on a horizontal shaft—these wheels may be worked on either ho1izontal or vertical shafts—and nses 8,000 cubic feet of water per minuteunder 38 feet fall, which, according to the rule, gives it nominally a 600-horse power. It diives sixty 95U-pound stamps, with 26 pans, 14 eettlere, 8 amalgamators, besides pumping, hoisting ore, ete. Another, 13% inches in diameter, working in a horizontal shaft on the Truckee river, is eawing 60,000 feet of lumber, daily, for the Nevada Lumber Co., workiny under a head of 120 feet. The Uclipse wheel, exhibited in a very neat model, by Baker & Hamiiton, is also a doub 6 turbine, d ffeiiug somewhat frum the Leffel. It 1s cheaper iu price, aud, accoraiug tu the Lowell Reporte on wa'er-wheel trials, reaches @ percentage of frum 55 to 75 per cent. of the theoretical value of the water employ-d. Itis estimated that there are about 1,000 waterwheels other tban turbines in use on this coast miking in all about 1,300. But the time will eoou come when this number will be largely increased. No State in the Uvion promises such uvlimited wat -power as Calitornia, and the time is not far distant when this advantage will be sufficiently imp:oved to make this the most importaut manufacturing Stute in the Duion. Machinery and Tools. The range of industrial operatioue or mechanical processes by whioh raw materials are

. MINING. AND SCIENTIFIC -PRESS. [September 12, 1874. W. B, EWER.:..-0+0 ++.. SENIOR EDITOR, DEWEY & Co., Publishers. A, T. NEWEY, ss GEO, H. STRONG. W. B. EWER, INO. Li. BOONE. Office, No. 224 Sansome St., 8S. E. Cnrner nf California St., San Franciscn. SuBeoRnwr0Ne payahle in advance—For one year, $4; Six months, $2.25; three monthe, $1.25. Remittances hy registered iotters or P. O. orders at our risk. ANVEERTISING RaTES.—1 week. 1month. 3months, 1 year Per line. 25 80 $2.00 $5.00 One-haif . $3.00 $7.50 24.00 One inch. 2 5.00 14.00 40.00 Large advertisements at favorahle rates. Special or reading notices, legal adver ti ti 53) ng in extraordinary type or in particular parts of the paper, inserted at special rates. San Francisco: Saturday Morning, Sept. 12, 1874. TABLE OF CONTENTS, GENERAL EDITORIALS. — The Old Soggs Mine; Mending Cracked Belle; Tripartite Chain Connector, 161. Casting a Patch: New Procees of Working Black Sand; Discovery of Sapphires; Central Pacific Hoepital; Class Exhihit—9th Induetrial Exhihition, 168. Leffel's Donhle Turhine Wheele, 169. Obromium; Academy of Sciences; Patents and Inventions, 172. ILLUSTRATIONS.—Quinian’s Chain Connector; Device for Mending Sroken Beile, 161. Leffel’s Im. proved Patent Globe Casing, 169. SCIENTIFIC PROGRESS. — Vegetation Inside an Egg: Light and Electricity; Hydrium; the Siphon; Thermometers; Yellow Glass for Photographic Purpoees; The Microxcopic Examiration of Well Water; Wilt it Work? Manufactnre of Gun Cotton, 168. MECHANICAL PROGRESS.—The Firat Tool Used hy Man; Aero-Steam Enginee; Iron Clad Vessela: Economy of Iron Cars; How Thimbles are Made; Europesn Crdnance; Double Chronometer Bank Lock, 163. MINING STOCK MARKET.—Table of Daily Sates and Prices and’Comparative Prices for the Week; Notices of Aseessments; Meetings and Dividends; Review of Stock Market for the Week, 164. MINING SUMMARY from various counties in Oalifornis and Nevada, 164-165-172. GOOD HEALTH. —Engiish Food Adulteration; Cautione Concerning the Use of Paris Green; Dog Dentistry; The Eyes ang Spectacles; Middle Age; Byes and Cold Water; Obesity and Hezith; The Teeth, 167. USEFUL INFORMATION. — Building Housee; Gilding and Siivering Silk Thread; Urnamentation of Giass; How to Make a Good Bed; Plate Polishing Powder; Test of Steei: Curriage Springe: Rawhide Journals; To Take Stains out of Ivory, 167.MISCELLANEOUS. — Indusiriat Fairs —Exhihitione of the Mechanics’ Institute; The Sonora Company; Smatl Business; Quartz Mines of Washington and Eureka; Loading Hay, 162. Machinery at the Fair; Prospect for Ciliformia Tohacco; Sorghum; Tellurets; Revival of Sineltiug at White Pine; The Howiand Tunnei; The Rye Valley Mines; Important to Inventors; From Tyho, 166. Wore of the Black Bear Company; The Mines at Bennock; Petroieum in Ventnra County: Tue New Boulder Ditch; Is Mining a Legitimate Businese? New Mill; Mining vs. Farming; A New Fume Arrester; Troy District; Gone Proepecting, 170. THE-Village of Yon Bet, situated abont eix miles northeast of Nevada city, was destroyed by fire on Wednesday last. The place contained bnt few business honses, which were totally coneumed, save Fox & Oliver’s store, and an old nnocenpied building. Tux Inter-State Induetrial Exhibition opened in Chicago on the 9th inst. Itis in every particular far superior to the exhibition of last year, since all the departments are mere complete and the decorations and fixtnres much handsomer. American InstituTE.—The fourth annual exhibition of the American Institute was formally opened in New York, on the 9th inst. The display in all departments is said to be more varied aud extensive than in former years. THE mills near Dayton are working to their full capacity, some on tailings, and others on nre from the Belcher and other Comstock minee. A large quantity of wood is piled upon the banks of the river, ready for shipment to Gold Hill and Virginia, Jamzs Connery, chief of the boiler depariment of the Baldwin Locomotive Works, has invented a new eystem of caulking boiler seams, and a naval commission has been ordered to examine and report upon its merits, It is rnmored that engineere are out to locate the line of the Southern Pacific railroad from Bukersfield to San Fernando, and that the company will soon oommence active operations in the way of road building. TuHE process of refining ie now in full blast at the smelting works at Sacramento, employing eome 20 men night and day. Smelting will be resumed at these works as soon as the new furaces are complete, which will be in a few daye. Cres. JOHNSON discovered 2 lead of stonecoal about 28 miles south of Eugene city, on the East Fork of the Willamette, one day last week. The outcroppings indicate a rich depoeit. 2 H. B. Puatr, the lessee of tbe coal mines near Tone oity, will ship 500 tons to Stockton immediately. The vein is 10 feet thick and constantly improving, A New Process of Working Biack Sand. We have received several letters of inquiry in relation to the process and machinery employed by the Perseverance Black Sand mining compsny to amalgamate the infiuitesimal particles of gold and separate’ the fine or floured quicksiiver from the black sand, which was noticed in this paper some weeks since. The President of the compsny has furnished ns . with the leading features of the process, which will enable those acqnainted with such matters to judge of its merits, The sand is first screened so as to materially reduce its bulk, and then snbjected for about twenty-four hours to 2a solution composed of canstio potash and common selt in proper quantities. This is for the purpose of remoying any coating or oxide that may be upon the gold, and destroying sulphur and other base substances which would be absorbed by the quicksilver. to its injury. The pulp is then hea’edin a pan bya jet of steam (being constantly stirred), which takes but a few minutes, as it should not be too hot, and then the quicksilver is poured in and the steam and agitation continued from fifteen to thiity minutes, when the gold becomes thoroughly amulgamated, and the pulpis discharged into a vat to cool before putting it throngh the separaling sluice. The heat has the effect of expanding or partially vaporizing the qnicksilver, and, aided by the agitation, distributes itall through the sand pulp iu very fine particles, like flour, where it meets and amatgumates with the equally flue and universally diffused particles of gold. Care must be exercised in the heating, ae too much heat flonrs the qnicksilver moie than is necessary to secure pertect amalgamation, and tbereby increasee the difficnity of collecting it. together again withont serious lose. When we consider the faotthat the amount of hext required to raise the temperatnre of one pound of water from 32° to 212° will raise that of about 30 pounds of qnicksilver throngh the same range, the reason for thie cantion is obvione. There is reason to believe that most of our millmen have fallen into the common error of nsing too much heat in amalgamating the precions metals. It is proper to state here that great oare is taken to purify the quicksilver, by proper means, before it is pnt into the puln, upon every occasion of nsing it, as euccees depends much upon having the quicksilver in good condition. Retorting alone ie not always sufficient, as some of the base metals volatilize and pass over with the mercurial vapor. The last and most difficult operation is that of sep :rating the fine particles of smalgam and quicksilver from the heavy black sand, and collecting them together again without too great loss; for it mnst be remembered that black sand cannot be treated like quartz pulp, on account of its greater sprcific gravity. The fine particles of gold and qnickeiiver cannot be wholly precipitated by agitation or a ec .ncentcating motion, because they are so minnte and light in comperison to the grains of sand, that they will not settle by their own gravity through the heavy sand, as through qnariz nlp. B This difficulty is overcome and separation secured without material loss, by this company, by means of a systeni of palvanized copper roliere, grooved spirally, and placed side by side and in layers one above the other, so asto “break joints’’ and not qnite touoh together, and extending across the sluice, which is three feet or more in width. A soreen is placed over them to distribute the sand and water as they fall upon them, and a galvanized eopper plate beneath to catch the qnicksilver asit dripsfrom them. Two or three layers of these rollers are thus arranged at two or more places a few feet apart in the sluice, and drop tiffleeor wells are sunk across the bottom a little below the copper plates, to receive and retain the quicksilver as it runs off fromthem. The rollere are one foot in length, »nd one and a half iuches in diameter and hollow, six or eight of which are lnid side by side und end to end extending across the width of the sluice. These, as also the copper plates, are kept in a highly sensitized condition and tree from verdigris, andas the pulp passes down over and between their multiplied surfaces it necessarily brings the fine particles of quickeilver into contact with some one of them to which they will adhere, before passiug through the whole of them as arrangedin the sluice. Ae the quicksilver accumulates upon the rollers it drops from the under side, and the amalgam is cleaned from them in the same,manner es from the platee. Theee amalgamating rollers and their application to both the cradle and the sluice, are the invention of William Subl:tt of this city, who has applied for a parent therefor, and have been frecly tested by the Perseverance company, who areabout to employ them in exteneive operations in black sund mining at the month of Rogue river, where they have valnable claims. Now that a practical method of treating the auriferous beach sands of onr nortbern coast appears to have been found, we hear of other parties about to engage in this class of mining, which promises to attract great attention another season, J. McM. Suarrer will deliver the annual address before the Sonoma and Marin Agricnltnral society this yoar. Discovery of Sapphires. Discoveries of varions kinds of minerals and precious stones have been made lately in the United States of Colombia, and that country will before long take a fair. place among the

mineral-producing regions of the globe. ‘The placer mines in varions States are now yielding considerable gold, since the hydraulic process in vogue in this State is now extensively used there. Several American and English companies are working the hydraulic mines, and some of them are doing very well. in a conversa ion this week wilh Mr. Morales, Colombian Cousul at this port, he told us that severs] sapphires had recently been fouud in the State of Cauca. They were brought here by Dr. Weaver, and the man who found them told the doctor that there were many of these stones there. The lapidaries to whom the stones were shown pronounced them sapphires and-valuable, but not of the right color to be very valuable. They thiuk, however, that if further search is made, sapphires of proper color to he of value will be found. These stones, which we examined, are a little too clear and light colored to be handsome. The two larger ones shown us would have been worth $500 each, if of a deeper color. One of ahout half the size, the lapidaties pronounced worth $50, even with th: off color; 60 the find is a g 10d one, after all. The stonés were fouod accidentally on the surface, and tho ground will probably now be worked deeper, to eee if darker colored eapphires cannot be found. The man who found them was not aware of their real value, nor wae Dr, Weaver until they had been examined by the lapidaries. The eapphires were fonnd in the Stute of Cauca, on the interior side from the western range of the Andes, They are genuine sapphires, but not of the proper color 10 minke them very valuahle. The stones are quite lirze, and will ehortly be cut and set. Sapphires are next in hardnese to diamonds. They are found in various colore, and are much admired, heing of value according to the tints of the stone. The Central Pacific Hospital. The Central Pacific Railroad Co., that much abnsed corporation and ‘‘soulless monopoly,” ought to have more credit than it receives for some things it doee. For instance, the company hae a five hospital at Sacramento for the accummodation of the employees of the railruad, as well as for strangers who are hurt on the road. Half the time the passengers are injured by their own carlessness, or by non-compliance with ihe rulee of the company; nevertheless, they ure taken in and cared ior in the best manner possible hy the Coeutral Pacific people. The hospital is situated on G street, andthe building is sufficiently largo for the p.tients now tbere, andformauy more. There is an air of comfortubout the place not usually met with in public hoxpitals. There are no loug faces, no pititul compluiuts, and every want is met by skilltul attéudants, The library is particularly worthy of mention, and no doubt most of the convalescents bless the liberality of a company which providee for the comforte as well as the necessariee of life in such a place. The ventilation of the building, the arrangemeutsand style of beds, surgical appliances, the kitchen, dining rooms, étc., all evince skill and jndgment. The grounds are neatly laid out, and the place generally is comfort thle, olean and pleasant. Mr. Forbes, the steward, attends faithfully to hie duties, and the whole hospital is exceliently managed, furnishing a pattern which others might follow with benefit. Tue fifth anunal exhibition of Moutana, under the atispices of the Agricultural, Mineral and Mechanical Association, commences on the Territorial fair grounds, near Helena, on the 14th inst, A BAR of pure gold, weighing 312 ounces, was the result of eight days’ run of an 8-stamp mill on quartz from the Cabell ledge, in Baker conuty, Oregon. THE Virginia and Truckee railrond company will introduce the Westinghouee patent air brakes on their passenger coaches ut un early day. Tue Gilroy Consolidated Cigar Factory manufactured 200,000, and shipped 250,000 cigars for the month of August. Tue Lyou county Times reports the discove ot about 200 acres of mineral coal land in El Dorado canton. Tue Eureka mill, Carson river, worked about 6,000 tons of ore Jast month. This is the biggest run by the mull. THERE are six wagon-making establishments in Petaluma, and all are busily employed at present. . Tue water in Carson river is now very low and irregular in its flow. A bust of 700 ponnds of powder was put off in the American mine, at San Jun, on Saturday. THE Creed & Rutler mine, iu Co!orado, was recently sold to a Holland company for #3,000,~000. . Class Exhibit—9th Industrial Exhibition, Prime Movers—Water Wheels. In our ennmeration and notices of prime movers, we inadvertently overlooked ‘‘waterwheels,’’ of which there are two exhibitors. Motive machines, as steam engines, water wheels and windmills are simply contrivances: interposed between the power—the steamboiler, the waterfall or the wind—and the work to be done, Their form and combination of mechanical principles is supposed to comprise the most economio and convenient means for taking up the power at d sposil and conveying it.to the various appliances for perfurming the work required. Thus in the use of water there are various classes of wheels termed overshot, breast, undershot and turbine wheels, according to tbe manner in which the water is bronght upon them. In calenlating the power of a water wheel we multiply the weight of water by the hight throngh which it falls. Thus: 500 cubio feet of water (which weighe 30,000 pounds), falling through one foot of hight in aminute, represents, conventionally, onehorse power; 50U cnbie feet falliog through ten feet per minute, represents ten-horse power; 10v0 cubic fret falling through four feet per munnte repreeents eight-hor-e power, etc. In any water wheel the puwer actually obtained from the water passing throngh it ie only a certain proportion of the caloulated power, from the faot that much power is loet by the shocks und changes of velocity which it experiences ou entering und leaving tbe wheel, and by the friction on thejounate uf the same; aleo inthe furm of the buckets, the general conetrnction of the wheel, tbe fasteniug of the aims, the axle, etc. In prac ioal use the losses alising from the differeut torms of wheels are substantially about as tollows: In the best turbines, trom 15 to 20 per cent.; in indifferent turbiues, 25 to 40 per cent.; in overshot wuee!s, 30 tu 40 per cent.; in breast wheels, 40 to 45 per cent.; in the best uudershot wheela— hurdy-gurdies with light work—50 per cent., and 1rom 60 to 70 in others. From this it will be seen that the turbine is the most effective form uf water-wheel in nse. iis compact torm and small liability to get out of order, and ready adjuetmeut for work, are also impuitant advautayes connected with its nse. Lhere are hut two exhibitors of water wheels in the Pavilion, hoth of whom exh bit tnrhine wheels only. Mr. Myers exhibits tive of L ftel & Myers’ untbiue wheels, all of large, working dimengions; aud Baker & Hamilton exhibit a smi mudel of the Ecl.p-e Double Lu. bine. The turbine wheel was intrudnced into Europe abont foity yeurs ago, and from theuce to the United States ahout ten years later. It was fir-t known here asthe Paiker Turbine wheel, a moditicaion of the European Joinville. A turbine wheel differs «sentially from avy other in receiving and dircharging water in wil directlons around its axis; and in the fuither fact that it losce but & mere moiety of efficiency when snbmerged. ‘lhe modilcations of this wheel are very nnmerous; not less than oue hundred and twenty-five patents on such modificatiuns have been taken out in this country alone within the last ten years. The Leffel wheel shown hy Mr. Myets seems to have distanced all cumpetitors iu the reputation which it has secured, and in the numberein use. Over 3,000 are now in use in the United Statee, of which 300 are enumerated in California and Oregon, and abont 100in Utah. It is employed here for all sorte of work, as for runnivg quaitz milis, flour mills, woolen mills, saw miils, ete. It is constructed of varioue dimensions, from three or four horse-power up to turee or fuur hundred horse-power. One of these wheelsis the only power employed in driving the largest quartz mill on this coaet— tuat of the Union Mill Company, on the Carson river, This mill—a double Leffel turbine—ig only 52 inches in diameter, and 1s placed on a horizontal shaft—these wheels may be worked on either ho1izontal or vertical shafts—and nses 8,000 cubic feet of water per minuteunder 38 feet fall, which, according to the rule, gives it nominally a 600-horse power. It diives sixty 95U-pound stamps, with 26 pans, 14 eettlere, 8 amalgamators, besides pumping, hoisting ore, ete. Another, 13% inches in diameter, working in a horizontal shaft on the Truckee river, is eawing 60,000 feet of lumber, daily, for the Nevada Lumber Co., workiny under a head of 120 feet. The Uclipse wheel, exhibited in a very neat model, by Baker & Hamiiton, is also a doub 6 turbine, d ffeiiug somewhat frum the Leffel. It 1s cheaper iu price, aud, accoraiug tu the Lowell Reporte on wa'er-wheel trials, reaches @ percentage of frum 55 to 75 per cent. of the theoretical value of the water employ-d. Itis estimated that there are about 1,000 waterwheels other tban turbines in use on this coast miking in all about 1,300. But the time will eoou come when this number will be largely increased. No State in the Uvion promises such uvlimited wat -power as Calitornia, and the time is not far distant when this advantage will be sufficiently imp:oved to make this the most importaut manufacturing Stute in the Duion. Machinery and Tools. The range of industrial operatioue or mechanical processes by whioh raw materials are