Volume 35 (1877) (426 pages)

138 ‘ MINING AND SCIENTIFIC PRESS [September 1, 1877. The Combination Shaft. One of the Great Mining Projects of the Day. The Chollar-Norcross-Savage shaft, or, as it ig more generally called, the Combination shaft, is now nearing the level of the Sutro tunnel. So near eachother have the workings of these two great mining projects come, says the Gold Hill News, that the hlasts in the tunnel are distinctly heard by the workmen in tbe shaft. Nor is this very wonderful when it is considered that bere remain only about 1,050 feet of rock hetween the two points, and tbat the charges used in the tunnel are very heavy, several in number and are all exploded at the same instant of time by electric exploders. The discharges of blasts in the Combination sbaft are also distinctly heard in the east drift, 1800-foot level, of tbe Chollar-Potosi, the distance between the two points being about 900 feet. The tunnel liue, it will be rememhered, bowever, is 365 feet north of the shaft. A Great Mining Project. Every day sbows more conclusively the wisdom of going half 'a mile east the main line of the present boisting works of the Comstock and of sinking a monster shaft perpendicularly to tbe ledge. Should the general dip of the Comstock be maiutained to greater depths, this monster shaft will strike the vein about 2,800 feet from the surface. The same wisdom which conceived the project is being exemplitied in carrying it on. Everything is ou a scale commensnrate with the nndertaking itself. Before a spade or pick was struck to even grade off the the locality of the present works, preparations for convenient access were made,and a side track from the Virginiaand Truckee railroad and a wagon road to the site projected. Then commenced the grand preparations, the plans of which had all heen fully matured by I. L. Reqna, the chosen Superintendent of the shaft. The Site, Shaft, Works, Ete. The site selected for the sbaft was.a most eligible one. From it the view of the city is particularly fine. 1t stands some 200 feet above tbe bottom of the ravine, and has dump room suificient for years. The site having been determined npon, a donble grade was made, the npper one of about three acres, for the hoisting works proper, and the lower one for tbe shaft, blacksmith and carpenter shops, etc. The shaft, which was started on tbe lower grade, is the largest and finest on the lode. The actual excavation is 10 feet 6 inches hy 30 feet 6 inches. The shaft, when timhered by 14 by 14 timhers of spruce, has four compartments, three heing Shy 6 in the clear, and the fonrth, or pump compartment, being 6 hy 7 feet. Its deptb is now about 1,550 feet. The main huilding is 60 hy 140 feet, 20 feet high and contains the hoistingand pumping engines. The roon is well igbted aud easy of access, being on, the wpper grade, and reached by both wagon road and side track. It extends out over the shaft room and affords ample space for offices when needed at the works. The Shaft Room and Shops Are situated on the lower grade, The former is 40 by 60 feet and 32 feet high, that heing the ditierence iu altitnde of the two grades. The east side of the room is the wall extending from the lower to the npper grade. This wall is eight feet in thickness at the hottom, 32 feet bigh, and built of hewu granite. It contains fonr vertical piers, and is pierced for the sbaft end of the pump hob. The carpenter shop is at the soutbwest corner of the sbaft room, is 40 hy 80 feet, 16 feet high, and fitted up with tbe usual facilities for preparing timbers, etc. The machine is run hy a 35 horse-power engine, The timbers, etc., are all dumped from the upper grade, right where wanted. The blacksmith shop is at the west end of the main structure, is 30 by 60 feet, and 20feet high. It contains two forges driven by a blower. The drying room is south of the main building, and is 30 by 50 feet. The boiler room is north of the main building, is 40 by 50 feet, and 20 feet high, and contains two sets of largest-size boilers. 2 The Machinery Is ‘first-class in every respect. The hoisting engine is geared to 350 horse-power, and is sutticient to do the required work after the lode is reached as wellas before. It turns two reels, on each of which are wonnd 2,900 feet of cable six inches wide aud five-eiyhths of an iuch thick. Near the boistiug eugine is a double-geared steam winch, or pump-hoist, capable of lifting 80 tons. It moves slowly aud strongly, from 60 to 75 feet per minute beiug its most rapid movements. 1¢ has windlass heads on each end, and is used by means of a snatch block for moving heavy objects anywhere about the building, Tbe cable attached is seven inches by five-eigbths of an iuch, and made by Hallicdie & Co., San Francisco, of the best steel wires, It has the strength to handle the pumpsto the depth of 3,500 feet. The Pumping Apparatus Is second to none on the lode, It stands near the shaft and has never been used, there beiug very little water m the shaft. It is, however, all ready to run, and is a vertical compound condenser of 700-borse power, capable of running a double column of 12-inch, 8-feet plunger pamps toauy required depth. 1+ is controlled vy the Davy differential valve, aud can make one -stroke in 15 minutes, or 12 strokes in one minute. It is attached directly to the hishop hgad of the bob. The initial cylinder is 32 inches by 10 feet stroke, the expansion cylinder is 64 inches + 3,000 feet of grouud. by 8 feet stroke. The engines, ppmps and bob weigh 150 tons. The beam of the bob is all iron and weighs 52 tons. There are 10 sticks for pump rods on hand, each 15 by 15 and 100 feet long, Oregon pine, and cost here $300 each. They are tbe finest sticks ever seen on the Comstock. being as straight as arrows and of the clear stuf The joints at the ends of these as they go together to form the rod will be cut square and oak keys fitted and driveu in so as to make all solid ag the uative stick. These joints will be still nore tirmly secured by iron straps 10 inches wide, one inch thick aud 36 feet long, one on each side. These sticks are all nnmbered and bored, and the plates are also numbered and perforated to correspond. In the side of tbe sbaft room panel doors bave been placed, one above another, and above a section of the floor made movable for the purpose of handling these sticks for pump rods. he pnmps are all on hand ready to be put in. The Sheaves, Skeet, Etc. The sheaves and tbe construction of the gallows frame are nnique and wortby of particular mention. The frame is built wpou the top of the stone wall above mentioned. ‘The sheaves are 18 feet in diameter, and so set as to carry the cable over to the center of the shaft below. The faces of the sheaves are eight and a balf inches wide, filled with oak wood to prevent crystalization. They are so constructed as to stand the strain of 100 touseach, At tbe end of the eable, instead of a cage, is found a skeet, an excellent inventiou of Mr. Requa, capable of holding five tons of rock, and which dispenses with all station teuders, as by an ingenious contrivance it dnmps and righte itself. It saves the bandling of au immense amount of dead weight. Itis still now most of the time, bnt brings np 100 tons of rock and 16,000 gallons of water daily, and there are reqnired to rn all the saws, machinery, éte., and do this work only 20 cords of wood per week. When the works are all completed and in running order, and three of these skeets nsed, 2,000 tons of rock can be raised per day. Miscelianeous Mention. This shaft is situated 2,327 feet east of tbe Chollar-Potosi shaft. It was recently plnmbed and found to be but one-qnarter of an inch out of the way nortb and south, and one-half an inch east and west, which shows what kind of work Mr. Reqnais doing. It is so smooth and straight that the skeets pass np ano down witbout bearing against the guides. The general arrangement of the works is as perfect as any ou the lode, and was all planned hy Mr. Requa. In bringing the pnmp rods from San Francisco they were loaded on four flat cars, the weight, bowever, heing borne principally by the end ears. In this manner all the twists and turns of the railroad were made iu safety. The rope bouse is 200 feet east of the main bnilding, so thatin case of fire the works will not be endangered. The company own 35 acres of laud where the works are situated, and every time the place is visited, the wisdom of the nndertaking, aud the excellence of the arrangements made hy Mr. Requa to carry it ont, are made more and more apparent. Nevada County Copper Interest. Down in Rough and Ready township, on the range hetween Peun Valley and the Ronud Tent House, is a portiou of an extensive copper belt which at the present time is exciting considerable interest amoug miners and capitalists, and is destined iu the near future to receive still more attention, In 1862-3 there were very lively times in the viciuity of Spenceville, and the excitement there became intense on account of the discoveries made in that section. Thousands of claims were located and shafts were sunk on them in every divectiou. It is said that the whole district for teu miles in width and twenty miles iu length was peopled with prospectors who were searching for copper lodes and talking copper. Shares in some of the claims sold for a bnndred dollars per foot, and almost any kind of a claim was considered valuable. The ore in all the ledges coutained a per cent. of copper that would pay-to mine and reduce in Europe, and many of them were said to assay from three to thirty per cent. A shipment of ore from one of the claims to Swansea 1s said to have paid $35 per ton above the expense of mining, shipping and reducing. The helt is said to be literally covered with lodes, almost all of which would pay for work if the ore could be reduced at a low cost. In 1863 that desideratum was not reached and the section was abandoned. Some years ago Mr. Deetkin, an experienced mining expert and engineer, coucluded to experiment nupon the ore, and accordingly re-located what was kuown as the **Well Lode,” at Spenceville. He cxpended considerable money and a good deal of time, but did not achieve satisfactory success. He was sneceeded in the management of the property hy Mr. C. Borger, a thoroughly scientific and experienced miner, who bas, by repeated experiments and continued practical work, at last demoustrated, heyond a doubt, that copper mining can be successfully and proftably carried ou in that section. The property is owned by an incorporated company knowu as the San Francisco Copper Mining Compauy. They own Vhe lode at the depth of 80 feet is at some places 125 feet wide. The ore averages, by working process, about six per ceut copper. ‘The balance is composed of iron, sulphur and zinc, in about the following proportions: 40 per,ceut. iron, 45 per cent. suphiur, 2 per cent, silica, from {2 to 4 per cent, zine. Mr. Borger has so perfected his method of working that $54 can be realized as protit from every ton of ore raised and reduced. Last month the expenses of the compauy were $2,500. They extracted 22 tous of copper, that sells from $300 to $320 per ton in market, which, as readily will be seen, affords a nice profit, To obtaiu this resnlt there were only 25 tons of ore reduced per day. Tbe works will be enlarged inside of 60 days, so that 40 tons per day can be worked. All that is necessary in order to obtain any given amount of money per day from these claims is to fignre how many tons of ore it will require and then extend the works so as to reduce that numbcr. The ore body is practicably inexhaustible and will increase in value as it is sank upon without a doubt. The Superintendent informs us tbat tbe ore in bis ledge is the lowest grade of any in the district, but it has the advantage of being the largest, and as it can be worked at a nice profit, is perbaps tbe most valuable. The process by which tbe ore is now successfully worked hy Mr. Borger is not claimed to be a secret, but only asuccessfnl one for reducing this class of ores. It is rude, but cheap and ettective, and to Mr. Borger tbe county is indebted for guaranteeing the certaiu development, iu the near future, of one of the most important iuterests witbim its bonndaries. The ore is raised by means of steam hoistiug works from a perpendicular shaft to a tramway ahout 20 feet above ground. From there it is pushed wn cars to the ore or roasting bouse—a large building, we should think, 250 feet in leugtb and in the neighborbood of 40 feet in widtb, the sides of which are notinclosed. Here the ore is dumped into heaps of about 30 feet in leugth, 10 or 15 feet iu width and six or eight feet high. There are two rows of these in the building. 1n the center of the heap is abrick flue. Brush and wood is placed under the ore and set on fire. In ignites the sulphur contained in the mass, which burns until the heap is thoroughly roasted. It takes abont four months for aheap to hurn ont. From the roasting beaps the ore is taken toa vat honse on the side hill above, where it is damped into a series of vats and snbmerged in water which is heated to a boiling temperature by means of steam, The liqnor from these vats is condneted automatically from point to poiut till it reaches large revolviug tubs, in which are placed scraps of old irou which precipitate the copper. Tbe pnlp is then taken ont aud put into drying pans, when the work of reduction is complete. Itis proper to state that tbe heated water does not extract but little above half the copper{ while in the vats, so it becomes necessary to dump the residue into a pile and still further jeech it. From this dump-pile a contiuual stream of liquor runs which is strongly impregnated with copper, and which is conducted into the revolving tanks by the same means as the liqnor from the vats. From this source a continnal sonree of revenue is obtained whether the other part of the works is running or not. In other words, anew mine is being formed all the time which will yicld a steady profit at no cost whatever. The ore is mined and raised to the surface on a contract for $1.10 per ton, and the contractors furnish all their own supplies. When these facts are taken into account it will readily be seen that copper mining in Nevada connty is destined at no destant day to become one of its most important interests. Tbe field is exteusive, and the success of min‘ng there is beyond question since Mr. Borger bas discovered a way to work the ore successfully. His metbod, as said before, is no secret, and he promises to explaiu it fully to any who desire to engage in working lodes in that district. The works can be erected at a .very small cost compared to the expense of erecting works for operating a qnartz mine, with the additional advantages of a certainty of a liberal profit and a lasting permanency, It will not be a great while before that section will be the liveliest and most prosperous part of the county. —Nevada Gazette. A New Mexican Process. We condense tbe following from an article in the Federalista, a Mexican journal, translated hy Mr. A. Leon Cervantes for the San Lnis Obispo Tribune, ou a new process for reducing metals: Three years ago, Senor Ignacio 8. Portugal came from the interior (State of Jalisco) to demand a privilege for a system of reducing metals, invented by bimself. Said system obtained the approval of several of our most distinguished metallurgists, to whom Senor Portngal explained bis system. It was then seen that the principles on which said system was based were perfectly adjusted to the data of science; the only thing wantiug was to search in practice the confirmation of the theory, tbat is tosay: to prove that the imagined apparatus corresponded to the proposed object. The press then occupied itself several times in this important bnsiness, and also published satisfactory reports of competent persons iu the matter. Having obtained the respective privilege, Senor P. proceeded to assay his system; hut, as frequently occurs, he met with uuexpected difficulties, by which he comprebended that the hard task of bis scientific observations had not ended.: Nevertheless, instead of dismaying at such obstacles, be attacked them with indomitable energy, succeeding finally, after two years of unremitting studies and experiments, in seeing his efforts crowned, and tbe problem which has heen the thought of all his life, resolved. The following report by persons, whose scientific anthority no one douhts, is the hest support that can be conferred on the new system, which, already perfected by its author, is destined, as we have said before, to exert an incalculable infinence for the good of-our country. Indeed, by Senor P.’s method, ores whose reduction can not he profitable by the methods now in nse can be treated profitably. As the action of the fre is hmited to beating only and not to smelting, it follows naturally a ednsiderableeconomy iu combustibles. The rapidity with which the rednction is made, the natnre of the substances employed to make it,. the instantaneons amalgamation, the loss of no precious metal, the utility of all component metals, and many other iucalcnlable advantages of this system demonstrate very clearly the great economy in time and money that can be introduced in the mineral industry, and, of course, the vast development of which this industry is susceptible. Report. “Invited by the Citizen Ignacio S. Portngal to examine bis system of reduction of argentiferons ores, we visited his laboratory and were much pleased to see the results he obtained.” . ‘The said system consists, lst. In the transformation of the snlpbnrets into oxides and in the reduction of the latter to metals. 2d. In tbe amalgamation of the metals reduced. 3d. In the separation of the same. ‘The tirst operation is effected in a furnace invented by Senor P., of which we examined a well detailed model. In this furnace the transformation and reduction of the ores can be made very rapidly and at a temperature very inferior tothe one that wonld he necessary to smelt them, To tbis cirewnstance, which implies a great saving of combnstible in comparison to the ordinary smelting system, we ought to add that tbe condition of the furnace permitts that the redneed minerals, in cooling, cede their heat to those enteriug afterwards into the furnare. Some of the advantages that we find in this system of reduction consist in the facility with which the sulphur of the sulplurets can be bad; and there being no fusion of the mineral, tbere is no loss of precious metals, as it happens in the ordinary reduction by fire.” Senor Portugal snbmmitied to our examination some portions of mineral ready prepared by his system, and we saw with satisfaction that the reduction had been perfect, as we had only to wash the earths with a little water to separate the varions metals which formed the hases of the compounds previously existing in the mineral. The amalgamation of the ores so reduced is instantaneous and complete; the mercury gathers with the greatest facility all those metals capahle of amalgamation. We examined afterwards the mass of metals and the remaining dust. In the former we eould recognize gold, silver, lead, copper, zinc and antimony, and in the latter we conld not find any vestiges of precious metals. Seuor P. showed to ns varions methods hy which he conld separate easily and economically allthe compounds of the amalgam. It is here where we saw the most notable advantages of this system, as not only the precious metals can he obtained, hut also those we mentioned before, whice are lost in the other systems. Senor P. separates tbe iron which is not capahle of a direct amalgamation by a physical operation easily executed. These are briefly the experiments that we saw in practice which demonstrated to us that the author of this system, with an nnexemplary fixedness of purpose and self-abnegation, has worked for a long time to perfect the metalurgic method which he tried to plant some time ago. Tbe chemical theory of the new system is rational and the experiments in accordance with its indications. Senor P. bas made a laborions calculation to demonstrate the economy in time and money fonnd in his system ahove all others. (Signed) GuMERINDO Menpoza, Professor of Chemistry. (Signed) Mariano Barcena, Assayer and Separator of Metals, titled. (Signed) Francisco Kasxa, Professor of Chemistry. (Signed) Jose M. CEsar. City of Mexico, March 8th, 1877. A Foupixe Boat.—A few days ago a new and ingenionsly constructed portable boat was launched and tested on the Clyde. The hoat, which is eight feet in length, and two feet eight juebes in hreadth, is composed of hickory wood and constructed in such a way as permits of its beiug folded up till it assumes the appearance of a somewhat large traveling case. When packed it contains the oars, seats, canvas covering, with sufficient space left for other necessaries, and as the whole weighs hut little over 56 pounds, it can he easily carried about from place to place. Before being put mm the water, the fraine of the hoat is drawu ont to its full length, and covered on the bottom and sides with a strong water-proof canvas covering, The process of unpacking and fitting the boat witb its covering ready for tbe water occupied only the space of three minutes. Worxine tHe Fiur Dusr.—Everything is moving along very smoothly at the Lemmon mill, The lessees were very much anuoyed when first starting up by the constant breaking down of parts of the machinery that had become impaired aud rusted by long disnse. This not only necessitated frequent stoppages, hut also a largely increased money outlay. Messrs. Clark & Wallace’s indomitable perseverance has trinmphantly overcome all these obstacles and the process is an assured snecess, and is another element in Eureka’s continued prosperity. — Eureka Sentinel.

138 ‘ MINING AND SCIENTIFIC PRESS [September 1, 1877. The Combination Shaft. One of the Great Mining Projects of the Day. The Chollar-Norcross-Savage shaft, or, as it ig more generally called, the Combination shaft, is now nearing the level of the Sutro tunnel. So near eachother have the workings of these two great mining projects come, says the Gold Hill News, that the hlasts in the tunnel are distinctly heard by the workmen in tbe shaft. Nor is this very wonderful when it is considered that bere remain only about 1,050 feet of rock hetween the two points, and tbat the charges used in the tunnel are very heavy, several in number and are all exploded at the same instant of time by electric exploders. The discharges of blasts in the Combination sbaft are also distinctly heard in the east drift, 1800-foot level, of tbe Chollar-Potosi, the distance between the two points being about 900 feet. The tunnel liue, it will be rememhered, bowever, is 365 feet north of the shaft. A Great Mining Project. Every day sbows more conclusively the wisdom of going half 'a mile east the main line of the present boisting works of the Comstock and of sinking a monster shaft perpendicularly to tbe ledge. Should the general dip of the Comstock be maiutained to greater depths, this monster shaft will strike the vein about 2,800 feet from the surface. The same wisdom which conceived the project is being exemplitied in carrying it on. Everything is ou a scale commensnrate with the nndertaking itself. Before a spade or pick was struck to even grade off the the locality of the present works, preparations for convenient access were made,and a side track from the Virginiaand Truckee railroad and a wagon road to the site projected. Then commenced the grand preparations, the plans of which had all heen fully matured by I. L. Reqna, the chosen Superintendent of the shaft. The Site, Shaft, Works, Ete. The site selected for the sbaft was.a most eligible one. From it the view of the city is particularly fine. 1t stands some 200 feet above tbe bottom of the ravine, and has dump room suificient for years. The site having been determined npon, a donble grade was made, the npper one of about three acres, for the hoisting works proper, and the lower one for tbe shaft, blacksmith and carpenter shops, etc. The shaft, which was started on tbe lower grade, is the largest and finest on the lode. The actual excavation is 10 feet 6 inches hy 30 feet 6 inches. The shaft, when timhered by 14 by 14 timhers of spruce, has four compartments, three heing Shy 6 in the clear, and the fonrth, or pump compartment, being 6 hy 7 feet. Its deptb is now about 1,550 feet. The main huilding is 60 hy 140 feet, 20 feet high and contains the hoistingand pumping engines. The roon is well igbted aud easy of access, being on, the wpper grade, and reached by both wagon road and side track. It extends out over the shaft room and affords ample space for offices when needed at the works. The Shaft Room and Shops Are situated on the lower grade, The former is 40 by 60 feet and 32 feet high, that heing the ditierence iu altitnde of the two grades. The east side of the room is the wall extending from the lower to the npper grade. This wall is eight feet in thickness at the hottom, 32 feet bigh, and built of hewu granite. It contains fonr vertical piers, and is pierced for the sbaft end of the pump hob. The carpenter shop is at the soutbwest corner of the sbaft room, is 40 hy 80 feet, 16 feet high, and fitted up with tbe usual facilities for preparing timbers, etc. The machine is run hy a 35 horse-power engine, The timbers, etc., are all dumped from the upper grade, right where wanted. The blacksmith shop is at the west end of the main structure, is 30 by 60 feet, and 20feet high. It contains two forges driven by a blower. The drying room is south of the main building, and is 30 by 50 feet. The boiler room is north of the main building, is 40 by 50 feet, and 20 feet high, and contains two sets of largest-size boilers. 2 The Machinery Is ‘first-class in every respect. The hoisting engine is geared to 350 horse-power, and is sutticient to do the required work after the lode is reached as wellas before. It turns two reels, on each of which are wonnd 2,900 feet of cable six inches wide aud five-eiyhths of an iuch thick. Near the boistiug eugine is a double-geared steam winch, or pump-hoist, capable of lifting 80 tons. It moves slowly aud strongly, from 60 to 75 feet per minute beiug its most rapid movements. 1¢ has windlass heads on each end, and is used by means of a snatch block for moving heavy objects anywhere about the building, Tbe cable attached is seven inches by five-eigbths of an iuch, and made by Hallicdie & Co., San Francisco, of the best steel wires, It has the strength to handle the pumpsto the depth of 3,500 feet. The Pumping Apparatus Is second to none on the lode, It stands near the shaft and has never been used, there beiug very little water m the shaft. It is, however, all ready to run, and is a vertical compound condenser of 700-borse power, capable of running a double column of 12-inch, 8-feet plunger pamps toauy required depth. 1+ is controlled vy the Davy differential valve, aud can make one -stroke in 15 minutes, or 12 strokes in one minute. It is attached directly to the hishop hgad of the bob. The initial cylinder is 32 inches by 10 feet stroke, the expansion cylinder is 64 inches + 3,000 feet of grouud. by 8 feet stroke. The engines, ppmps and bob weigh 150 tons. The beam of the bob is all iron and weighs 52 tons. There are 10 sticks for pump rods on hand, each 15 by 15 and 100 feet long, Oregon pine, and cost here $300 each. They are tbe finest sticks ever seen on the Comstock. being as straight as arrows and of the clear stuf The joints at the ends of these as they go together to form the rod will be cut square and oak keys fitted and driveu in so as to make all solid ag the uative stick. These joints will be still nore tirmly secured by iron straps 10 inches wide, one inch thick aud 36 feet long, one on each side. These sticks are all nnmbered and bored, and the plates are also numbered and perforated to correspond. In the side of tbe sbaft room panel doors bave been placed, one above another, and above a section of the floor made movable for the purpose of handling these sticks for pump rods. he pnmps are all on hand ready to be put in. The Sheaves, Skeet, Etc. The sheaves and tbe construction of the gallows frame are nnique and wortby of particular mention. The frame is built wpou the top of the stone wall above mentioned. ‘The sheaves are 18 feet in diameter, and so set as to carry the cable over to the center of the shaft below. The faces of the sheaves are eight and a balf inches wide, filled with oak wood to prevent crystalization. They are so constructed as to stand the strain of 100 touseach, At tbe end of the eable, instead of a cage, is found a skeet, an excellent inventiou of Mr. Requa, capable of holding five tons of rock, and which dispenses with all station teuders, as by an ingenious contrivance it dnmps and righte itself. It saves the bandling of au immense amount of dead weight. Itis still now most of the time, bnt brings np 100 tons of rock and 16,000 gallons of water daily, and there are reqnired to rn all the saws, machinery, éte., and do this work only 20 cords of wood per week. When the works are all completed and in running order, and three of these skeets nsed, 2,000 tons of rock can be raised per day. Miscelianeous Mention. This shaft is situated 2,327 feet east of tbe Chollar-Potosi shaft. It was recently plnmbed and found to be but one-qnarter of an inch out of the way nortb and south, and one-half an inch east and west, which shows what kind of work Mr. Reqnais doing. It is so smooth and straight that the skeets pass np ano down witbout bearing against the guides. The general arrangement of the works is as perfect as any ou the lode, and was all planned hy Mr. Requa. In bringing the pnmp rods from San Francisco they were loaded on four flat cars, the weight, bowever, heing borne principally by the end ears. In this manner all the twists and turns of the railroad were made iu safety. The rope bouse is 200 feet east of the main bnilding, so thatin case of fire the works will not be endangered. The company own 35 acres of laud where the works are situated, and every time the place is visited, the wisdom of the nndertaking, aud the excellence of the arrangements made hy Mr. Requa to carry it ont, are made more and more apparent. Nevada County Copper Interest. Down in Rough and Ready township, on the range hetween Peun Valley and the Ronud Tent House, is a portiou of an extensive copper belt which at the present time is exciting considerable interest amoug miners and capitalists, and is destined iu the near future to receive still more attention, In 1862-3 there were very lively times in the viciuity of Spenceville, and the excitement there became intense on account of the discoveries made in that section. Thousands of claims were located and shafts were sunk on them in every divectiou. It is said that the whole district for teu miles in width and twenty miles iu length was peopled with prospectors who were searching for copper lodes and talking copper. Shares in some of the claims sold for a bnndred dollars per foot, and almost any kind of a claim was considered valuable. The ore in all the ledges coutained a per cent. of copper that would pay-to mine and reduce in Europe, and many of them were said to assay from three to thirty per cent. A shipment of ore from one of the claims to Swansea 1s said to have paid $35 per ton above the expense of mining, shipping and reducing. The helt is said to be literally covered with lodes, almost all of which would pay for work if the ore could be reduced at a low cost. In 1863 that desideratum was not reached and the section was abandoned. Some years ago Mr. Deetkin, an experienced mining expert and engineer, coucluded to experiment nupon the ore, and accordingly re-located what was kuown as the **Well Lode,” at Spenceville. He cxpended considerable money and a good deal of time, but did not achieve satisfactory success. He was sneceeded in the management of the property hy Mr. C. Borger, a thoroughly scientific and experienced miner, who bas, by repeated experiments and continued practical work, at last demoustrated, heyond a doubt, that copper mining can be successfully and proftably carried ou in that section. The property is owned by an incorporated company knowu as the San Francisco Copper Mining Compauy. They own Vhe lode at the depth of 80 feet is at some places 125 feet wide. The ore averages, by working process, about six per ceut copper. ‘The balance is composed of iron, sulphur and zinc, in about the following proportions: 40 per,ceut. iron, 45 per cent. suphiur, 2 per cent, silica, from {2 to 4 per cent, zine. Mr. Borger has so perfected his method of

working that $54 can be realized as protit from every ton of ore raised and reduced. Last month the expenses of the compauy were $2,500. They extracted 22 tous of copper, that sells from $300 to $320 per ton in market, which, as readily will be seen, affords a nice profit, To obtaiu this resnlt there were only 25 tons of ore reduced per day. Tbe works will be enlarged inside of 60 days, so that 40 tons per day can be worked. All that is necessary in order to obtain any given amount of money per day from these claims is to fignre how many tons of ore it will require and then extend the works so as to reduce that numbcr. The ore body is practicably inexhaustible and will increase in value as it is sank upon without a doubt. The Superintendent informs us tbat tbe ore in bis ledge is the lowest grade of any in the district, but it has the advantage of being the largest, and as it can be worked at a nice profit, is perbaps tbe most valuable. The process by which tbe ore is now successfully worked hy Mr. Borger is not claimed to be a secret, but only asuccessfnl one for reducing this class of ores. It is rude, but cheap and ettective, and to Mr. Borger tbe county is indebted for guaranteeing the certaiu development, iu the near future, of one of the most important iuterests witbim its bonndaries. The ore is raised by means of steam hoistiug works from a perpendicular shaft to a tramway ahout 20 feet above ground. From there it is pushed wn cars to the ore or roasting bouse—a large building, we should think, 250 feet in leugtb and in the neighborbood of 40 feet in widtb, the sides of which are notinclosed. Here the ore is dumped into heaps of about 30 feet in leugth, 10 or 15 feet iu width and six or eight feet high. There are two rows of these in the building. 1n the center of the heap is abrick flue. Brush and wood is placed under the ore and set on fire. In ignites the sulphur contained in the mass, which burns until the heap is thoroughly roasted. It takes abont four months for aheap to hurn ont. From the roasting beaps the ore is taken toa vat honse on the side hill above, where it is damped into a series of vats and snbmerged in water which is heated to a boiling temperature by means of steam, The liqnor from these vats is condneted automatically from point to poiut till it reaches large revolviug tubs, in which are placed scraps of old irou which precipitate the copper. Tbe pnlp is then taken ont aud put into drying pans, when the work of reduction is complete. Itis proper to state that tbe heated water does not extract but little above half the copper{ while in the vats, so it becomes necessary to dump the residue into a pile and still further jeech it. From this dump-pile a contiuual stream of liquor runs which is strongly impregnated with copper, and which is conducted into the revolving tanks by the same means as the liqnor from the vats. From this source a continnal sonree of revenue is obtained whether the other part of the works is running or not. In other words, anew mine is being formed all the time which will yicld a steady profit at no cost whatever. The ore is mined and raised to the surface on a contract for $1.10 per ton, and the contractors furnish all their own supplies. When these facts are taken into account it will readily be seen that copper mining in Nevada connty is destined at no destant day to become one of its most important interests. Tbe field is exteusive, and the success of min‘ng there is beyond question since Mr. Borger bas discovered a way to work the ore successfully. His metbod, as said before, is no secret, and he promises to explaiu it fully to any who desire to engage in working lodes in that district. The works can be erected at a .very small cost compared to the expense of erecting works for operating a qnartz mine, with the additional advantages of a certainty of a liberal profit and a lasting permanency, It will not be a great while before that section will be the liveliest and most prosperous part of the county. —Nevada Gazette. A New Mexican Process. We condense tbe following from an article in the Federalista, a Mexican journal, translated hy Mr. A. Leon Cervantes for the San Lnis Obispo Tribune, ou a new process for reducing metals: Three years ago, Senor Ignacio 8. Portugal came from the interior (State of Jalisco) to demand a privilege for a system of reducing metals, invented by bimself. Said system obtained the approval of several of our most distinguished metallurgists, to whom Senor Portngal explained bis system. It was then seen that the principles on which said system was based were perfectly adjusted to the data of science; the only thing wantiug was to search in practice the confirmation of the theory, tbat is tosay: to prove that the imagined apparatus corresponded to the proposed object. The press then occupied itself several times in this important bnsiness, and also published satisfactory reports of competent persons iu the matter. Having obtained the respective privilege, Senor P. proceeded to assay his system; hut, as frequently occurs, he met with uuexpected difficulties, by which he comprebended that the hard task of bis scientific observations had not ended.: Nevertheless, instead of dismaying at such obstacles, be attacked them with indomitable energy, succeeding finally, after two years of unremitting studies and experiments, in seeing his efforts crowned, and tbe problem which has heen the thought of all his life, resolved. The following report by persons, whose scientific anthority no one douhts, is the hest support that can be conferred on the new system, which, already perfected by its author, is destined, as we have said before, to exert an incalculable infinence for the good of-our country. Indeed, by Senor P.’s method, ores whose reduction can not he profitable by the methods now in nse can be treated profitably. As the action of the fre is hmited to beating only and not to smelting, it follows naturally a ednsiderableeconomy iu combustibles. The rapidity with which the rednction is made, the natnre of the substances employed to make it,. the instantaneons amalgamation, the loss of no precious metal, the utility of all component metals, and many other iucalcnlable advantages of this system demonstrate very clearly the great economy in time and money that can be introduced in the mineral industry, and, of course, the vast development of which this industry is susceptible. Report. “Invited by the Citizen Ignacio S. Portngal to examine bis system of reduction of argentiferons ores, we visited his laboratory and were much pleased to see the results he obtained.” . ‘The said system consists, lst. In the transformation of the snlpbnrets into oxides and in the reduction of the latter to metals. 2d. In tbe amalgamation of the metals reduced. 3d. In the separation of the same. ‘The tirst operation is effected in a furnace invented by Senor P., of which we examined a well detailed model. In this furnace the transformation and reduction of the ores can be made very rapidly and at a temperature very inferior tothe one that wonld he necessary to smelt them, To tbis cirewnstance, which implies a great saving of combnstible in comparison to the ordinary smelting system, we ought to add that tbe condition of the furnace permitts that the redneed minerals, in cooling, cede their heat to those enteriug afterwards into the furnare. Some of the advantages that we find in this system of reduction consist in the facility with which the sulphur of the sulplurets can be bad; and there being no fusion of the mineral, tbere is no loss of precious metals, as it happens in the ordinary reduction by fire.” Senor Portugal snbmmitied to our examination some portions of mineral ready prepared by his system, and we saw with satisfaction that the reduction had been perfect, as we had only to wash the earths with a little water to separate the varions metals which formed the hases of the compounds previously existing in the mineral. The amalgamation of the ores so reduced is instantaneous and complete; the mercury gathers with the greatest facility all those metals capahle of amalgamation. We examined afterwards the mass of metals and the remaining dust. In the former we eould recognize gold, silver, lead, copper, zinc and antimony, and in the latter we conld not find any vestiges of precious metals. Seuor P. showed to ns varions methods hy which he conld separate easily and economically allthe compounds of the amalgam. It is here where we saw the most notable advantages of this system, as not only the precious metals can he obtained, hut also those we mentioned before, whice are lost in the other systems. Senor P. separates tbe iron which is not capahle of a direct amalgamation by a physical operation easily executed. These are briefly the experiments that we saw in practice which demonstrated to us that the author of this system, with an nnexemplary fixedness of purpose and self-abnegation, has worked for a long time to perfect the metalurgic method which he tried to plant some time ago. Tbe chemical theory of the new system is rational and the experiments in accordance with its indications. Senor P. bas made a laborions calculation to demonstrate the economy in time and money fonnd in his system ahove all others. (Signed) GuMERINDO Menpoza, Professor of Chemistry. (Signed) Mariano Barcena, Assayer and Separator of Metals, titled. (Signed) Francisco Kasxa, Professor of Chemistry. (Signed) Jose M. CEsar. City of Mexico, March 8th, 1877. A Foupixe Boat.—A few days ago a new and ingenionsly constructed portable boat was launched and tested on the Clyde. The hoat, which is eight feet in length, and two feet eight juebes in hreadth, is composed of hickory wood and constructed in such a way as permits of its beiug folded up till it assumes the appearance of a somewhat large traveling case. When packed it contains the oars, seats, canvas covering, with sufficient space left for other necessaries, and as the whole weighs hut little over 56 pounds, it can he easily carried about from place to place. Before being put mm the water, the fraine of the hoat is drawu ont to its full length, and covered on the bottom and sides with a strong water-proof canvas covering, The process of unpacking and fitting the boat witb its covering ready for tbe water occupied only the space of three minutes. Worxine tHe Fiur Dusr.—Everything is moving along very smoothly at the Lemmon mill, The lessees were very much anuoyed when first starting up by the constant breaking down of parts of the machinery that had become impaired aud rusted by long disnse. This not only necessitated frequent stoppages, hut also a largely increased money outlay. Messrs. Clark & Wallace’s indomitable perseverance has trinmphantly overcome all these obstacles and the process is an assured snecess, and is another element in Eureka’s continued prosperity. — Eureka Sentinel.