Page:Encyclopædia Britannica, Ninth Edition, v. 4.djvu/778

Rh 702 CALIFORNIA valuable localities in search of something better, always hoping that deposits of unheard-of richness would be developed. Occasionally a kind of frenzy would seem to seize on them, and thousands would flock to some new and perhaps distant locality, on the strength of newspaper reports, where many would perish from disease and starvation, the rest returning in poverty and rags. Thus, in 1855, the Kern River fever raged through the State, at least 5000 miners going to that distant region of the Sierra, only to find that the gold deposits were limited in extent, and already worked out. In 1858 the &quot; Fraser River rush&quot; occurred ; and this was more disastrous to California than the most deadly pestilence would have been ; for it caused a terrible amount of suffering. Nearly 20,000 men left the State for that remote region, where few met with even moderate success, while all suffered great privations, and many died, the survivors coming back in a state of complete destitution. The shallow &quot; placer diggings &quot; of California are now pretty well worked out, and the gold at present is chiefly obtained from the hydraulic mining operations and from the quartz veins. The deep or high gravels, as they are indiscriminately called, and which are worked by the hydraulic process, lie chiefly in Nevada, Placer, and Sierra counties, in the region extending between the branches of the American and Yuba rivers. These gravels are usually associated with heavy deposits of volcanic materials, and, indeed, they are often entirely covered by immense flows of lava, under which the work ings are carried by means of tunnels. All the operations connected with the exploitation of the large hydraulic &quot; claims &quot; are usually on a grand scale. As much as twenty-five, or even fifty, tons of powder are sometimes used in a single blast to loosen the gravel, so that it can be acted on with ease by the jet of water thrown from the &quot; pipes.&quot; To give an idea of the force of the agent thus employed, it may be stated that, when a six-inch nozzle is used, under a head of 300 feet, as is sometimes done, not less than 1 600 cubic feet of water are discharged in one minute, with a velocity of 1 40 feet per second. The water, as it thus issues from the nozzle, feels to the touch like metal ; and it retains its cylindrical form unbroken until it strikes the gravel bank at a distance of a hundred or more feet. The detritus, thus powerfully acted on, crumbles rapidly, and the disintegrated material is carried by the current into the sluice-boxes, where it leaves its auriferous particles in the &quot;rifles,&quot; which are chinks or cavities between the bars or blocks of wood or stone with which the bottom of the sluice are lined. Gold-mining in the solid rock or quartz -mining, as it is usually called, because the gangue or vein-stone which carries the gold is almost exclusively quartz is also extensively carried on in California, having been begun as early as -1851. The mines are scattered over the State from San. Diego to Plumas counties ; but the most important and productive ones are in Amador and .Nevada. The distribution of the gold in the veins is exceedingly irregular, and, consequently, the business of quartz-mining has been, in most cases, a very uncertain one. A large number of the principal workings are on, or in the neighbourhood of,. what is known in California as the &quot; Great Quartz Vein,&quot; or the &quot; Mother Lode,&quot; an immense development of quartz, which has been traced from Mariposa County to Amador, over a distance of eighty miles, not continuously, but in a series of nearly parallel belts, or lenticular masses, with barren intervals between them ; these have very nearly the same direction, and are parallel with the axis of the Sierra. It is on the Great Quartz Vein that the celebrated Mariposa mines are situated ; which, however, have not, on the whole, proved successful. In the same position are the mines of Amador County, among which the one formerly called the Hayward Mine is the best known, and for a long time- one of the most profit able. The mass of quartz worked in this mine was of great size, although of low tenure in gold. It was, for some years, the deepest mine in the country ; but several of those on the Comstock Lode in Nevada have now attained a considerably greater depth. Silver-mining has been attempted in many localities in Silver. California, and much money spent in trying to develop the argentiferous lodes which have from time to time been discovered. A few years ago, there was a great excitement on the very summit of the Sierra in regard to supposed valuable silver-bearing veins, and particularly at a locality called Meadow Lake, in Nevada County. Quite a number of mining camps and towns were built up, one of which had for a time several thousand inhabitants. Nothing permanently valuable was discovered, however, and the region was soon entirely abandoned. The most persistent efforts have been made, for the past ten years, to work argentiferous deposits in the volcanic rocks near the summit of the Sierra, in Alpine County, at and near Silver Moun tain. Although it does not appear that any mine in this region has been successful, the expenditure is still kept up. Slate Range, a little to the east of Owen s Lake, was the scene of considerable excitement some ten or twelve years ago, rich silver ores having been discovered there ; but it was found that mining could not be made profitable in .that distant region destitute of water and fuel. Quite recently, the Panamint Range, in the same vicinity, has attracted much attention. The only paying silver mines in the State seem, however, to be those in the Inyo Range, at Cerro Gordo, where the ore is chiefly galena, rich in silver, and also containing considerable gold. The yield of this district in the year 1872 was nearly a million of dollars in value, six-tenths of which was silver. Quicksilver has been extensively mined in California, the Quick mine of this metal at New Almaden, Santa Clara County, silver, having been worked previous to the gold excitement. All the workable deposits of cinnabar thus far known to exist are situated in the Coast Ranges, and they are chiefly limited to the metamorphic Cretaceous group of rocks, in, which they are associated with serpentine, imperfect jasper, horn- stone, and chalcedony. By far the most important mines are those at New Almaden, a few miles west of San Jose. These produced, in their palmy days, during the years 1853 to 1857, and 1861 to 1869, from 2,500,000 to 3,500,000 Ib of quicksilver per annum. In 1870, the production had fallen off to 1,000,000 Ib. The total production of the New Almaden mines between 1850 and 1870 was a little over 40,000,000 Ib. The New Idria Mine is in Monterey County, about ninety miles south of New Almaden. This has also been, for some years, a quicksilver-producing locality of considerable importance. Cinnabar also occurs in con siderable quantity at numerous places north of the Bay of San Francisco, in Napa and Lake counties. The most important mine in this region is the Redington, near Knoxville, in Lake County. The export of this metal from California was, in former years, very large, reaching, in 1868, the amount of 44,506 flasks, or 3,404,709 Ib; in 1870, it was only 6,359 flasks, although the production for that year was estimated at 28,600 flasks, or 2,187, 900 ft), of which 12,000 were the product of the New Almaden mine, 7600 of the New Idria, and of the remainder, about one-half was from the Redington, and the rest from various smaller mines north of the Bay of San Francisco. Copper ores occur in a great many localities within the Copper limits of the state of California, and at some of these a large amount of work has been done, although at the present time there does not seem to be a single locality where the ores of this metal are now mined. Quite large masses of nearly pure native copper, mixed with the red oxide have