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furnaces, about $15 per ton as freight charges by these ships, and about $4 per ton for bags in which to carry it; or $27 per ton for carrying the ore to the nearest market, a sum nearly equal to the average value of all the copper ores obtained from the mines in England and the continent of Europe. Such mines as are located further inland, or in localities removed from main travelled thoroughfares, have to meet additional costs for transportation.

This expensive transportation compels a closer examination of the ore than would otherwise be necessary, and this work has all to be done by hand, in order to select only such of it as may be sufficiently rich to warrant the expense, requiring considerable skill on the part of the laborers employed. This operation costs, at a very low estimate, $1 per ton for such ore as may be selected, and causes a waste, in some classes of ore, amounting to ten per cent. by mixing the crumbled rich ore among the slate and refuse, which is thrown on the dump pile, for want of a ready means for its separation.

The costs for bags alone, unavoidable under the present system, has been the cause of the stoppage of the work on several good mines. These bags are an enormous tax on the copper resources of this coast. There are no means, under

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this system, of avoiding this expense, as shipowners will not carry the ore to New York or Boston unless it is in bags. Occasionally, a cargo of one grade ore has been shipped to Swansea in bulk; but as it is very rarely that an entire cargo belongs to one party, or is of one grade, it is very rarely that this method of shipment is adopted. These bags are scarcely ever returned, and consequently are nearly a total loss. Meader & Co., who are largely connected with the shipping business, secure the return of a small portion of their bags, but as they have undergone the wear and tear of a six months' voyage round the Horn in a damp hold of a ship, and been subjected to the rough handling in scores of movings, they are of comparatively small value when returned.

The class of laborers employed, and the wages paid for their services, are another material condition greatly influencing the costs of copper mining on this coast. The average wages of copper miners, American or European, in California, except at Copperopolis, is about $3 per day. The Keystone and Union, the two largest companies at that place, pay $2 60 per day to all their laborers, whether they work above or below ground. Other companies in the valley pay $3 per day for drifters, and $2.50 per day for all other laborers. Many of the companies in other portions of the State employ Chinamen almost exclusively for all work done above ground, who work for $1 per diem. As these Chinamen, under proper supervision, do as much work, and as well as any other class of laborers, it follows that those companies that employ them effect an important saving of expense. The owners of the Copperopolis mines have not introduced this class of labor in that locality lest it might create disturbances among the miners, of whom there are about eight hundred in the valley. These men, as is usual with their class, have an intense hatred to the Chinese, a feeling which is not by any means allayed by the knowledge that their presence and employment would insure a reduction in the rate of wages. It is quite probable the introduction of Chinamen to work on these mines would create considerable disturbance. But it is scarcely to be expected that proprietors of mines costing millions of dollars,, the returns on which depend on the economy with which they are worked, will be deterred from availing themselves of the services of the cheapest labor in the market, through fear of the acts of any class of citizens. It being so much to the interest of the State that every facility should be afforded to those engaged in developing its mineral resources, any interference on the part of individuals or combinations to prevent the introduction of cheap labor for that purpose would be severely punished.

The mines in Oregon and in the northern portion of California pay from $2 to $3 per day for laborers.

At the mines in Arizona most of the work is done by Mexicans, who are

satisfied with about $30 per month and a certain quantity of provisions. There are a good many Chinese employed at these mines, who are paid $30 per month and board themselves. The Americans and Europeans employed are paid from $50 to 60 per month in addition to their board.

The position of the mine, the facilities it possesses for working, is another important condition connected with the costs. Mines located in the lower level of broad valleys, such as those at Copperopolis, where they have to hoist everything taken out of the mine and to lower everything put into it by machinery, and to pump the seepage water of an extensive district from a sump hole five hundred feet in depth, labor under the greatest possible disadvantage. The costs of engines, their wear and tear, and the expense of their superintendence and repair, imposes a cost of more than $5 per ton on all the ores extracted from these mines. It is a fair estimate to calculate that every ton of ore taken from the Union and Keystone mines costs $16 per ton as it reaches the surface. This calculation includes the division of all the expenses attending the conduct of the business of the mine by the quantity of ore actually shipped. These figures, explaining the costs of working the copper mines when compared with those showing the value of their products, show why so many good mines have stopped work during the past year.

The present price of fifteen per cent. ore at Swansea and New York is less than $50 per ton. To obtain this it costs the mines at Copperopolis

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This does not include any allowance for loss by broken bags or carelessness in handling after shipment, or expenses for commissions, &c. It must also be remembered that not one-half of the ore extracted from these mines will average fifteen per cent. It is known that Meader, Lalor & Co. have shipped thousands of tons of ore which did not exceed twelve per cent. These Copperopolis mines, exporting nearly three-fourths of the ore, furnish unmistakable data on which to base a calculation of the very slight margin of profits that arise from copper, mining on this coast as at present conducted.

There are some mines, such as La Victoire, in Mariposa county, and those in some of the northern counties and in Oregon, in which the costs of extraction of the ore does not exceed $4 per ton, as they are worked by tunnels and require no hoisting or pumping. But the cost of transportation is much greater from all these mines than it is from Copperopolis, and the quantity of fifteen-percent. ore costs more for selecting. The quantity of carbonates, silicates, and oxides obtainable in any locality in California and Oregon is so unimportant as not to come within range of calculations concerning the costs of regular mining.

It cannot be possible that this present condition of affairs connected with the copper resources of the Pacific coast is without remedy, as the annexed table will show. The mines on this coast within five years of their discovery, in spite of every disadvantage of inexperience in the work of their development and want of knowledge of the nature of their ores, have exported nearly eighty thousand tons of ore, valued at the very lowest estimate at upwards of $5,000,000. A national source of wealth so productive in its infancy will not be left to die of inanition for want of the fostering care of the general government. As will be explained anon, to smelt the ores on this coast, with the present price of fuel

and the metal when made, would be but a partial and temporary remedy, the final success of which is involved in doubt. The recommendation of the chairman of the national revenue commission on this very point explains the only effectual plan that will secure the extended development of the copper resources of this coast. The following is a copy of the commissioner's recommendation referred to: "The commission therefore recommend that all excise duties on domestic copper be repealed; and that the duties on imported copper ores and copper be advanced to a moderate extent, or sufficient to relieve the copper mining interests of the United States from the depressing effects of the internal taxes upon their supplies, and to give to it as good a standing in our own markets, with reference to foreign competition, as they had before the present taxes were imposed."

4.-REDUCTION OF ORES.

Processes in use for smelting and concentrating the ores.-Numerous plans have been proposed and tested for the purpose of smelting and concentrating the copper ores found on this coast, none of which, for causes to be stated, have been entirely successful, though several of them have been partially so. A detailed description of all these various processes, and of the furnaces and apparatus used, while it might be both interesting and instructive, would be out of place in this report. Most of these plans which have been tested, on the large scale, have possessed some novel principle, which might be of advantage if employed in combination with old established processes, by those who possess the necessary skill, experience, and judgment to admit innovations upon systems under which they may have been educated. This seeming digression is intended to explain the principal cause of the failure of some of the most costly works that have been erected for the purposes to which this portion of the report refers. In not a few cases, those having charge of these works appeared to labor under the impression that it was so absolutely necessary to follow the old patterns introduced from their native land, that some German, French, and Cornish operatives seemed to attribute their failure to the fact that the laborers employed, and the materials used, did not understand the German, French, or Cornish language.

Early in 1862, works of an experimental character were erected at Antioch, on the banks of the San Joaquin river, near the base of Mount Diablo, for the purpose of testing the adaptability of the coal obtained in that vicinity, for smelting purposes; many persons, supposed to be authorities on the subject, expressing the opinion that such coal was unsuited for the purpose.

These works were erected under the direction of Mr. Thomas Price, an experienced Welsh copper miner, who has for several years been acting as agent for the Swansea smelters, for the purchase of copper ores on this coast-a gentleman of considerable scientific attainments and a first-class practical chemist and metallurgist. It may be proper to state further, that this gentleman, whose opinions on this subject of fuel should have much weight, is also professor of chemistry at the most famous college on this coast, and superintendent at the assaying and refining works of Kellogg, Hueston & Co., the most extensive private establishment in that business in the United States.

These works put up by this gentleman at Antioch consisted of a reverberatory furnace and roasting kiln, built on the plan of those in use at Swansea, but on somewhat smaller scale, and with a slight change in the form of the grate, to adapt it to the fuel. The furnace has a base of thirteen feet six inches long, by nine feet four inches wide, with a chimney-stack, for the purpose of creating sufficient draft and carrying off the fumes, sixty-five feet high. All these works were built of the best available materials.

As stated above, this furnace was built as an experiment, chiefly to test the

adaptability of the Mount Diablo coal for smelting purposes-to ascertain the quality and quantity of heat it generates.

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It would occupy too much space to enter into any extended details of the nature of this coal; but it may be necessary, to make the subject plain to those who have never paid any attention to the study of such matters, to state that in a reverberatory furnace the fire in its passage up the chimney strikes the roof, and is forced down upon the ore by means of a bridge," built between it and the burning fuel. In all flames, no matter how generated, there is one portion more intensely hot than the others. This is called the "reducing flame” because of its action in reducing ores, under certain conditions, into metals. All coals do not produce a flame of the same nature or length, and the operation of the reverberatory furnace depends, in a great measure, upon its being so constructed that the "bridge" is placed so that the reducing portion of the flame is caused to strike the ore at the proper point.

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After this explanation it will not require any technical or scientific knowledge of the principles of combustion to understand that a furnace to use fuel, which burns with a short flame and little smoke, requires great modifications in its construction when it is to be used to burn fuel which produces a long flame and much smoke. The experiments at Antioch settled this point clearly, if not satisfactorily, to those interested, and proves, for general information, that furnaces built on the plan of those used at Swansea, in which the short-flamed Welsh coal is used, are not adapted for the use of the long-flamed coals of the Pacific coast. But the question whether this long-flamed coal could not be used for smelting purposes, in a suitably constructed furnace, remains still unsettled Mr. Price states this Mount Diablo coal could be economically used for that purpose in a properly constructed furnace, but thinks no attempt should be made to proceed any further than in the conversion of .the ores into regulus. The price of all descriptions of coal being so much higher on this coast than a better article can be obtained in other countries, the refining of the metal can be more profitably done in those countries.

It is much to be regretted that the company, which expended nearly $50,000 in making these experiments at Antioch, did not carry them out to a full conclusion, by permitting Mr. Price to make such changes in the form of the furnace as his skill and experience may have suggested. But in California, where money commands from 18 to 24 per cent. interest, such experiments are not considered profitable.

The first bar of metal from the Antioch smelting works was received at San Francisco on the 14th of September, 1863, and created almost as much interest as the first bar of bullion from Washoe. During the time these works were in operation they produced about 200 tons of matt, or regulus, of an average of about 50 per cent., the balance being iron, sulphur, silica, &c. This was obtained from about 2,000 tons of ores from various parts of the State, but chiefly from Copperopolis, of an average of about 10 per cent., which the company advertised to purchase at the following prices :

71⁄2 per cent...

9 per cent..

10 per cent..

11 per cent..

12 per cent..

None were accepted below 7 per cent.

$15 per ton of 2,376 pounds. 17 per ton of 2,376 pounds. 19 per ton of 2,376 pounds. 21 per ton of 2,376 pounds. 25 per ton of 2,376 pounds.

The coal used in the operations cost about $7 per ton delivered on the grounds of the company. One ton of this coal, it was estimated, would reduce two tons of ore, after the furnace had become thoroughly heated; but in consequence of the difficulty in obtaining good materials for lining it the furnace was not kept steadily heated. The best imported fire-bricks, in consequence of the acH. Ex. Doc. 29-11

tion of the sulphur in the ore, would not endure more than about fifteen days. Work had consequently to be stopped within that period, and everything cooled off, in order to re-line the furnace. This entailed a great loss in the cost of fuel and labor, as well as of metal, and as the works were only calculated to operate on about eight tons of ore in twenty-four hours, these stoppages absorbea all the profits.

A Mr. Henry Davis, another practical Welsh copper smelter, who had been in charge of an extensive smelting establishment in Chili previous to his arrival on this coast, has made a number of experiments at the works at Antioch since they were closed by the original owners. This gentleman also expresses the opinion that the Mount Diablo coal, used in a properly constructed furnace, oculd be profitably employed in the reduction to regulus of such ores as will not pay to ship in bulk.

The smelting works erected at the Union mine, at Copperopolis, are on a more extended scale than those at Antioch. They cost nearly $75,000, and consist of two cupola blast furnaces, and other buildings, which were erected under the superintendence of M. Desermeaux, a French engineer, on the plans introduced on this coast by M. D'Heirry, a very skilful French metallurgist, who has erected similar works on the Queen of Bronze mine, in Oregon. The whole establishment consists of four large kilns for roasting the ores to deprive them of a portion of their sulphur, two large blast furnaces on the most approved German plan, with a powerful blast set in motion by a 20-horse power steam engine. The kilns are each capable of roasting 500 tons of one at a batch, which required from 7 to 12 weeks to burn, according to the weather and the care taken in laying them. After burning in these kilns the ore was placed in the blast furnaces, which are capable of operating on eight tons of such materials, each, in twenty-four hours. The only flux used in any of the operations was a portion of the slag from previous meltings, or silica in the form of quartz. The ore came from the furnaces, after the first operation in them, in the form of two qualities of regulus, the one containing about 80 per cent. of copper, the other about 40 per cent. This regulus was afterwards broken up and re-melted three or four times, in order to deprive it of all the sulphur, and to oxidize the iron as much as possible. No attempts were made to refine this matt into tough copper. The costs for fuel in these operations were exceedingly heavy, as charcoal, costing from 37 to 50 cents per bushel, had to be used This, together with the necessity for handling the materials so many times by expensive and unskilful laborers, rendered the operations so unprofitable that the works were discontinued after a few months' trial-not before some 5,000 tons of ores, averaging about 8 per cent., had been converted into regulus, which sold from $200 to $250 per ton, showing that these waste ores may be rendered valuable if they can be operated upon by some cheap process.

The smelting works at the Cosmopolitan mine, at Genesee valley, Plumas county, cost about $30,000. These are constructed on the plan described by Piggott, in his work on copper, somewhat modified by Mr. J. C. Chapman, one of the proprietors of the mine, under whose directions the works were built. The blast here is generated by two double-action piston bellows, four feet in diameter, set in motion by a large water-wheel. No ores have been operated on at this place except oxides, carbonates and silicates, and as long as plenty of such ores were attainable, this company was able to obtain respectable quantities of good matt and inferior copper; but when the supply ceased, they had to close up their establishment, as it was not adapted to operate on sulphurets.

At these works the molten materials were not drawn off into rough bars and remelted, as at Copperopolis, but they were run into a sort of cauldron built in front of the furnace, in which they were kept sufficiently liquid to allow the copper to fall to the bottom by its superior specific gravity; and as the slag,

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