Vicissitudes of Fortune in Mining.
The vicissitudes of fortune are probably more striking in mining for silver than in any other kind of mining. In all silver-producing countries we are told of mines being again and again abandoned because it was thought their rich “bonanzas” had been exhausted, but they have again and again been reopened and new and rich bodies of ore discovered. The Valenciana Mine, on the Veta Macbee (mother vein), of Guanaguato, Mexico, was reopened in 1760, on a part of the vein where work had been done in the sixteenth century, and which had afterwards lain as worthless for 200 years, and in 1768 a bonanza was struck at a depth of only 240 feet, from which $1,500,000 was extracted annually. And from 1788 to 1810 the annual average was still $1,383,195. At a depth of 1,200 feet the ore was considered too poor for extracting, and the mine was allowed to fill with water. Afterwards it was again opened and again paid immensely by working the almost inexhaustible quantities of low-grade ore.
The Veta Grande, at Zacatecas, which from 1548 to 1832 yielded $660,000,000, occurs in propalite, as does the Comstock, and has a similar structure, the vein branching out toward the surface, and dipping at an angle of forty-five degrees. It is, however, much smaller than the Comstock. It averages only about thirty-three feet, and eighty feet is its greatest width. In the upper part the ore was found concentrated in chimneys, but at depth it was found to be distributed through nearly the whole width of the vein. At first this low grade material could not be made to pay, but since it has been profitably worked and the bullion product has reached a high figure. Scores of such examples may be found in all silver-producing countries, as chronicled by Humboldt, Ward, Von Cotta, and others.
Even when no more large deposits of rich ore are to be found on the Comstock, there are immense and almost inexhaustible areas of low-grade ore upon which to fall back. In working these small bonanzas are sure to be encountered—scattered plums in the pudding—which will assist in sending up the average. New processes for working and concentrating ores are constantly being discovered, new methods in mining are being introduced, and new labor-saving machinery is almost daily being invented. Water-power, steam, compressed air, and electricity are fast taking the place of muscle. Each year machinery guided by mind is lessening the work to be done by mere power of muscle. Already the cost of milling has been greatly reduced, as has the cost of transporting ores and the cost of wood, lumber, and mining timbers. Present expenses will shortly be still further reduced.
TOWNS OF WESTERN NEVADA.
Virginia City.
Virginia City having been sufficiently well described in connection with the Comstock Lode, it now remains to briefly mention the other towns of Western Nevada. These all lie near the Sierras within a space of territory forty-four miles long and twenty-five miles wide—under the “eaves” of the mountains.