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ought to be done at the mines, where wood is much cheaper than in Eureka. 3. The furnaces must be differently constructed, i. e., the walls must come down straight to the hearth, or contract gradually about one foot in the whole height from top to bottom, like the Raschette or the Piltz furnaces; the mouths of the tuyeres ought to be narrowed from three to one and a half inches, and pressure blowers ought to be employed instead of the fan-blowers now used. The fore-crucible ought to be closed, so as to protrude not more than four inches from the breast at the commencement of the campaign, and not wider than six inches. 4. As long as no dust chambers can be connected with the furnaces, (which would undoubtedly be the best,) the stack ought to be rather wider than. the furnaces than narrower, so that the draught may be reduced to a minimum, and thus the escape of dust be prevented as much as possible. 5. Regular charges ought to be carefully mixed on the charge-floor, before the ore goes into the furnaces, which is not done now. The quartzose silver ores from New York and Secret Cañons, and no slag, should be mixed with the carbonates, so that a slag between a singulo and bi-silicate would be produced. Such a slag being hot, light, and not inclined to stiffening, mechanical losses of lead would be prevented, and the furnace-walls and crucible would last longer.

The Eureka Consolidated have been chiefly running on Champion and Buckeye ore, which is so easily mined that the whole cost of mining and hauling over two miles to the furnaces is only $4 25 per ton. In the fifty-six days immediately preceding the 30th of June, they smelted 765 tons 368 pounds of ore, which gave 238 tons of bullion, gross returns, for which, from New York, gave $348 per ton. The quantity of charcoal consumed was 25,832 bushels, worth 30 cents per bushel, delivered. From these figures it will be seen that it took about three and a quarter tons of ore to make one ton of bullion, and required, say, thirty bushels of charcoal to smelt one ton of ore. Ores from some twenty-five or thirty other mines have been smelted in the various furnaces, and the results show about the same figures. It may therefore be safely noted that in the Eureka district three and one quarter tons of ore make a ton of bullion, and thirty bushels of charcoal are required to smelt one ton of ore.

The above account was prepared for this report in August, 1870. Since then the Piltz furnace, in the course of erection at that time, has been completed by the Eureka Consolidated Company, and has proved a perfect success. Much of the former loss, occasioned by the unsuitable construction of the older furnaces, is entirely avoided in this one, and the consequence is a cheaper smelting and a higher yield in lead and silver.

The following article from the pen of Mr. Guido Kuestel, which appeared lately in the Scientific Press, gives a sufficiently clear idea in regard to the construction and working of the Piltz furnace, to answer all purposes for the present:

The want of furnaces so constructed as to permit the smelting of larger quantities of ore than hitherto effected with the old styles, led first to the introduction of the “Raschette" system, an arrangement by which the tuyeres, the form of the smelting space being rectangular, are placed in two rows, one of seven or eight on each long side, and are so arranged that the blast of one side strikes between that of the tuyeres of the other side. The figure, which gives a section of the furnace, explains this. The discharge of metal and slag takes place on the two narrow sides. The smelting result of these furnaces is greatly superior to that of the old-fashioned ones with one or two tuyeres, not only with reference to the larger quantity of ore smelted, in a given time, but also in saving a greater percentage of metal and fuel. The treatment of such a furnace, however, is delicate, and it required many months running before, by gradual improvement, a long smelting campaign was secured.

It is surprising that the rectangular shape was preferred to a circular one, for in

stance, one like the old iron-assay furnace of Sefstroem, with blast holes at equal distances on the periphery, the very effective result of which was well known. Mr. Aubel

gave an elaborate description of Raschett's furnace, alluding in the same to the circular shape. By theoretical reasoning he tried to prove that a circular form does not admit of a uniform smelting region, and that the consumption of fuel in the center would be a useless one. Notwithstanding this theory, Mr. Piltz, of Freiberg, Saxony, constructed a circular furnace, 5 feet in diameter in the clear, and with eight tuyeres, which has proved very successful, and which it is now proposed to describe.

For the sake of greater convenience in building, an eight-sided shape was chosen.

The first furnace of this kind was built, if I am not mistaken, about four years ago, at Halsbrucke, near Freiberg. From the start, the result was so favorable and so superior to Raschett's that, with slight modifications in regard to dimensions and number of tuyeres, at this time no other furnaces are in use at Freiberg. Aubel's theory did not prove to be correct. In a properly regulated smelting operation, no so-called "pigs" are formed either in the center or elsewhere; the slag runs con

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The Raschette Furnace-section through the tuyeres. tinually, undisturbed by crowbar opera

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The figures show a horizontal and vertical section of one of Piltz's furnaces. Ata is represented a cast-iron box, in which the brickwork, c, is placed, and the remaining space beaten ont with a composition, varying with the nature of the ore, generally being composed of one part of clay or loam and one part (volume) of charcoal, coke or anthracite, all powdered, mixed and moistened slightly. This compo sition is beaten in as hard as possible by means of wooden or iron pestles, and either the space is entirely filled and the crucible or receiver, b, then cut out, or the crucible is shaped during the stamping. The first method is preferable. There are two, sometimes three, tap-holes, da dog leading the metal into the do kettle, c. Above the crucible are seven tuyeres, g. The distance from g to the bottom of the hearth is 3 feet, and from g to the feeding-hole, 1, 10 feet. In case eight tuyeres are used, the last one is placed in front at i, a few inches higher than the rest, having at the same time a small inclination, so as to direct the blast to the same point in the center toward which are directed the other seven, which lie in a horizontal position. The breast, i, rests on a hollow cast-iron pipe, cooled by a constant current of water, as are the tuyeres. suspended in a cast-iron mantle. The advantage of this arrangement lies in the The upper part of the wall, k, is convenience and facility with which the fire-bricks above the tuyeres, which are mostly exposed to the action of heat and of dissolving substances, can be removed

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The Piltz Furnace-horizontal section.

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and replaced without interfering with the upper part. Being suspended, there is also free access to the furnace from all sides. In place of the "hanging suspension," other furnaces of the kind are provided with three or more iron pillars on which the upper masonry rests. The height above the tuyeres differs often greatly up to 20 feet. The section of the furnace widens always toward the feeding-hole, as this has a beneficial

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effect on the result of smelting. The force of the blast, finding a larger space in the upper region, is diminished as well as the heat, and the ore dust carried out does not amount to more than 1 per cent. The feeding aperture is at l. The gases, etc., enter dust-chambers before escaping through the chimney.

One of these furnaces is attended by one smelter, two slag-wheelers and three men to feed. Ore and fuel are regularly charged. The metal is tapped, from 18 to 20 times in 24 hours, into one of the two or three tap-kettles alternately. The slag runs continually into a slag-pot of cast iron of a pyramidal shape, the base being up. This cone is 29 inches high and 22 inches in diameter on the top. Matte, or globules of metal sink through the yet liquid slag to the bottom, in case any should be carried out. When stiff, the pot is turned over, the end of the slag-cone (where the metal or matte collects) broken off and melted over with the ore.

The blast or quantity of wind required is not very great-for each nozzle, about 125 cubic feet per minute, or for seven tuyeres 875 cubic feet, at a pressure of 1 inch quicksilver.

In the year 1868, a Piltz furnace, 20 feet high, smelted in 28 days:

Lead ores..

Piritous ores....

Tons.

545.00 50.30

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The slag contained 1.56 per cent. of lead and 0.71 oz. of silver per ton. The above 1,219 tons of smelting material (which are put into the furnace mixed together) consumed 109.8 tons of coke, (middling quality,) or 9 per cent., while the old Freiberg double-furnaces consumed 14 per cent., and other furnaces 20 per cent. and over.

According to the census returns the mines and smelting works at Eureka produced up to June 1, 1870, the following:

Eureka Consolidated Company, with 25 men, in six months
Buttercup Company, with 15 men, in four months..

Jackson Company, with 23 men, in five months.

Page & Corwin, (milling ores,) with 20 men, in twelve months...

Total.....

$295,000

50,000

120,600

135,000

600,000

This is, however, the product of seven furnaces and one mine, which sends her ores to Reno and Austin to be amalgamated; and of only a part of the year. The actual yield of the Eureka mines for the calendar year 1870 is not less than $1,200,000. Toward the latter part of the fall Messrs. Ogden & Dunne commenced the construction of cupelling works at Eureka, which were expected to be ready for work in December. The yield of the district increased steadily, and the bustle of active and prosperous business was apparent on all sides. In October, the Eureka Consolidated produced 222 tons bullion, worth $300 per ton. The two Buttercup furnaces produced 6 tons bullion per day. The Jackson Company's furnaces produced in October 923 tons bullion, worth $350 per ton. In the mean time new mines were discovered continually in the neighborhood, and at present it may be truly asserted that Eureka is one of the foremost districts on the Pacific slope. This view is sup ported not only by the number of good mines already known, but principally by the fact that these mines carry base metal ores, which all over the globe have been found to be the most permanent.

The total population of Lander County, according to the late census, is 2,815; 218 of which are Chinese.

NYE COUNTY.

Silver Bend or Philadelphia district, which attracted so large a share of the attention of mining men a few years ago, and was soon after almost deserted, has taken a fresh start during the last year.

This is principally due to the Transylvania and El Dorado lodes, from both of which rich ore has been extracted and worked, partly at Belmont, in Mr. Canfield's 10-stamp mill, and partly at Austin, in the Manhattan Mill. The Combination mill and mines have been idle. The Arizona and the northern extension of the El Dorado are spoken of as rich mines, but, so far as I am informed, work has not yet been resumed on them. The El Dorado South is described by Mr. W. F. Leon, the

agent of the company, in a recent publication in detail. I quote his account with slight alterations:

The claim is 1,000 feet lineal measurement in length, and covered by a patont from the United States Government to the present owners, making the title perfect. The property is owned by the following persons: W. F. Leon, 5334 feet, of which W. P. Buford has a small portion; Robert Mullen, 2334 feet; and C. F. Singletary, 2331 feet. The mining department is under the immediate supervision of Mr. Robert Mullen. As the value and importance of a mineral property depends so much or entirely upon the quantity and quality of the supply of ore, a closely detailed description of the El Dorado South lode cannot prove otherwise than interesting and acceptable to all parties engaged in mining. The deposits occur in a rather highly disturbed zone, extending in a northerly and southerly direction, with granite rocks close at hand on the west, and on the east slate and quartzite. The vein is a true fissure, and the gangue and selvage are similar in character to those of the most celebrated silver mines in Mexico, Peru, and Europe. Excepting about 250 feet at the southern extremity, the vein is plainly traceable throughout the entire property-in places by magnificent croppings, which rise three and four feet above the surface. Such outcrops are of an unusually massive character, and consist of a white, rather compact quartz, richly clouded with black and antimonial sulphurets of silver. Some of the most interesting and splendid specimens of surface silver ores are obtained from the exposed portions of the El Dorado South lode. Only a portion, however, of the vein-matter is in the solid condition represented by the prominent outcrops just described. In such solid portions of the ledge the silver most generally pervades the quartz in the form of sulphurets. Nearly the entire contents of the vein above water-level are more or less decomposed, and much of the ore occurs as chloride. The lode varies from 15 to 40 feet in width. The productive portion of the vein, the pay stratum, varies from 9 to 23 feet. It is found at times permeating the entire vein; at other times near the hanging wall. The vein has been opened at four different places along the lode for 600 feet by incline shafts and cuts. Shaft No. 1, at the northeast end, 132 feet deep; No. 2, at 80 feet south from first, 172 feet in depth; No. 3, the main incline or working shaft, 276 feet in depth, 220 feet south of No. 2; No. 4, at 300 feet from third, 60 feet deep, with cut-off 75 feet; making 640 feet of shafting.

At the depth of 240 feet in the main working shaft, at water line, a level is being run north in the solid ledge which is now in 60 feet, proving it to be over 11 feet in width, so far displaying one of the finest bodies of ore ever discovered, and impregnating the whole vein; beautiful crystallizations, including metallic silver, a combination of silver and antimony, horn silver or chloride of silver, stromeyerite, sulphuret of silver, stetefeldtite, the carbonate of copper, etc. Much of the best ore is associated with the oxides of copper and iron. In such cases the percentage of silver ore is very great, amounting at times to 25 and even 30 per cent. of the entire mass. A few assays of this body of ore have been made, varying from $53 to $1,866 per ton of 2,000 pounds. Recent reduction of ore from the solid ledge in main shaft, at water level, yielded per ton as follows:

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At the south workings an enormous mass of chloride ore, colored with iron, overrides the solid lode, which has worked at the mills in this place and Austin from $130 to $562 per ton. There are now on the different dump-piles 1,000 tons of first and second class ore. That being taken out from the main shaft, and added daily to the present large amount, proves the ore in sight above water line worth alone at least a quarter of a million of dollars. The improvements on this mine in the way of shafts, levels, houses, etc., have cost over $100,000, and nothing has been done but of a useful nature. At present a whim is being used for hoisting which will be replaced by steam-hoisting works recently purchased. The engine has a capacity of thirty horse-power. The policy pursued by the owners has been rather to prospect this famous lode than to seek for profit. Already over $130,000 has been the yield of ores reduced from this property, at an average of $175 per ton. After the steam-hoisting works get in motion, sinking on the ledge will be continued for permanent work, and at certain distances in depth different levels will be run north and south the entire length of the claim, So soon as the mine is properly opened reduction works of sufficient capacity will be erected to work all classes of ore taken from the mine by the company.

The latter part of Mr. Leon's article expresses a sound policy, one which, if it had been followed by more mining companies in Nevada, would have prevented many an ignominious failure.

Mr. Canfield intends to erect a new mill furnished with a Stetefeldt H. Ex. 10-9

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