List of mines in California surveyed from October, 1870, to January, 1872.

Total claims surveyed, 72. Placer, 34; quartz, 33; quicksilver, 4; copper, 1. Many of these have been patented, and on the others patents are pending.

Statistics of quartz-mills and mining ditches.-By the laws of California it is made the duty of the county assessors to return each year to the surveyor general of the State, among other statistics, a list of the quartz-mills and mining ditches in their respective counties. This duty is very imperfectly and carelessly performed, as will appear from an examination of the returns for the years 1867-'68 and 1869–270, on page 15 of the Mining Commissioner's Report for 1870, where. the errors in these tables are pointed out and commented on. I believe the following table, compiled from the surveyor general's report for 1871, though evidently more accurate than the two others referred to, is open to much criticism, and with this explanation I give it for what it is worth. It will be observed that there are no returns from two of our leading quartz-mining counties, Tuolumne and Plumas. According to Langley's Pacific Coast Directory, the former of these counties has 41 mills, with an aggregate of 445 stamps, and the latter 19 mills, with an aggregate of 233 stamps. Returns from those counties would have materially run up the total under the heading of "tons crushed," and shown, by comparison with the table of 1867-68, a great increase in this branch of mining. The table of 1869–’70, (page 15, report of 1870,) is so manifestly erroneous under this heading in the amount credited to Placer County, as to be useless for comparison.

Table of quartz-mills and mining ditches, as reported by surveyor general of California, for the years 1870 and 1871.

Great discrepancies exist between these returns and the list prepared by Mr. Langley for his directory, published in last year's report, (pages 463-469.) For instance, Langley gives Amador County 36 mills, or 9 more than the surveyor general's report; Mariposa County 29 mills, being 5 less than the surveyor generals report. He gives Nevada 74 mills, to 60 in this table, and Placer County 32 mills, while the assessor's returns show only 14. So in Sierra County, Langley 36 mills, and the assessor returns only 21. I cannot reconcile this difference except on the hypothesis that the assessors have not returned some mills which have not run for several years, while Langley has kept them on his list.

THE SOUTHERN MINES.

The term "southern mines" is an indefinite one, but is generally understood to embrace the country between the Cosumnes River on the north and the Chowchilla River on the south, a distance of one hundred miles, and include the counties of Mariposa, Tuolumne, Calaveras, and Amador. In width the mineral belt extends from the eastern edge of the San Joaquin Valley to an average altitude of 2,500 on the Sierras, a distance of forty miles east and west, thus embracing an area of 4,000 square miles.

This region of country was the scene of the earliest mining operations in California, as the surface placers were here more accessible and productive than further north; and within its limits are found the once populous and thriving mining towns of Mokelumne Hill, Columbia, Sonora, and Mariposa. Its population, as estimated in 1851, by Abbé

Alric, then parish priest of Sonora, was not less than 50,000, nearly all of whom were engaged in mining.

This extensive territory is cut and eroded to great depths by four principal streams, running from east to west, and crossing the course of the ancient streams, viz: the Merced, Tuolumne, Stanislaus, and Mokelumne rivers, which, with their tributaries, have acted as distributors of the auriferous deposits, and carried the gold from its original place of deposit to the banks and bars which yielded such enormous sums during the early days of mining. The waters of these rivers have since been diverted into ditches and flumes for mining purposes, and their principal tributaries run dry in the summer, giving the country a parched and desolate appearance during the greater part of the year. Within the area above described, scarcely a square mile can be found in which, even at this late day, a "prospect" cannot be obtained, although placer mining as a business has ceased to yield large returns, except in the opening of new ground at points where water has been lately brought in, or in the development of the ancient channels. Superficial placer, as well as river and bar-mining may be considered as practically exhausted, although operations are still prosecuted, on a small scale, on the limestone belt, and on the rivers during the short season of abundant water.

The principal mineral resources of the southern mines, at the present time, are vein-mining in the gold-bearing quartz belts and gravel-mining on the ancient channels. Within the limits of this region are found the rich and extensive copper belt, of which the town of Copperopolis is the central point; the Mother lode of California, one of the most thoroughly developed veins of gold bearing quartz in the world; and a system of veins running in the granites, high up in the Sierras, which are comparatively undeveloped. Other systems of veins, unconnected with either of the above, and on which extensive and profitable mining operations have been carried on for several years, occur near the contact line of the slates and granites. All these lodes and systems of veins have a general course of northwest and southeast, and are evidently true fissures. At many localities, among which we may instance Bald Mountain, east of Columbia, in Tuolumne County, smaller veins occur, with an east and west course, generally in the slates. This latter class have the peculiarities of gash-veins, most of them "pinching out" at a depth of from fifty to one hundred feet, and being generally richest above the water-line and near the surface. This class is known as "pocketveins." Although many so-called pocket-veins exist near to and parallel with the Mother lode, as at Angel's Camp, Calaveras County, where this class of mining is extensively carried on, it is generally believed they are outlying "stringers" of the main lode.

Copper mining.—An extensive belt of copper veins exists in the slates in the western part of Calaveras and adjoining counties, at an elevation above sea-level of about 1,000 feet. These veins were discovered in 1861, and subsequently developed to a depth of 500 feet, at Copperopolis, Calaveras County, maintaining their character for width of vein and grade of ore at lowest levels opened; but in 1867 operations ceased in consequence of the depreciation in the price of copper, and have not since been resumed. Up to the cessation of work the copper mines of California (the most productive of which are in the southern mining region) had exported 68,631 tons of ore and 847 tons of metal in bars. Up to that period nine smelting-furnaces had been erected in California at an aggregate cost of $236,000, all of which proved financial failures, and a majority of which were technical failures. When the copper mines of

Copperopolis were in operation, the price of freight to Stockton, the nearest shipping point, was $8 per ton, the distance being thirty-six miles. From that point it cost $2 per ton to San Francisco, whence it was sent to Swansea, Wales, at a further cost of $15 per ton. The total cost on each ton, mining, etc., included, when landed at Swansea, has been estimated at $50. Labor was then $4 per day. At this rate only firstgrade ores paid a profit; and with increasing depth, second-rate ores predominated. The consequence was the suspension of operations and the decay of the once flourishing town of Copperopolis. The principal mines are the Union, owned by Glidden & Williams, of Boston, Massachusetts, and the Keystone, the title of which is in litigation. Both of these claims are opened to a depth of from 400 to 500 feet, and have expensive and powerful hoisting and pumping-works.

The reopening of these mines will depend on the price of copper. This has been steadily decreasing in England since 1864, but the prospects of the trade are now much better than they were one year ago. The production of Chile, in 1869, reached the enormous amount of 55,000 tons, but it has since diminished to 49,000 tons, with prospects of a continued diminution. On the other hand, the demand for this metal is increasing.

Should the Stockton and Copperopolis Railroad be completed to Copperopolis, it is believed that with present prices of labor ($2 to $3 per day) these mines could be re-opened, and the second-class ores, of which large quantities are in sight in the mines, could be extracted and shipped with profit, as it is believed that the price of freight to Stockton would not exceed $1.50 per ton, and the total cost of laying down ores in San Francisco would not exceed $20 per ton, instead of $32 per ton, as heretofore. The re-opening of the mines, however, would require a large outlay of capital, and perhaps involve the erection of new hoistingworks. The Stockton and Copperopolis Railroad was completed as far as Milton, at the base of the Sierras, when operations were suspended in consequence of the closing of the mines. Ten miles more would complete the road, but its completion will depend very much on the price of copper in the marts of the world.*

The Mother lode.-The Mother lode of California is a vein, or, more properly, a series of veins of quartz which has been traced on a longitudinal line, with occasional interruptions, for a length of about seventyfive miles, from Bear Valley, Mariposa County, to Amador City, Amador County. Throughout the entire distance it has a general northwest and southeast course, and an almost uniform dip to the northeast of eighty degrees.

Whether this singular formation is a "lode or a mere accidental occurrence of a series of veins on a longitudinal line in the same belt of slates, is a question on which eminent mining engineers have differed. It has been discussed in the report of J. Ross Browne of 1868, and in my report of 1869. Mr. Skidmore considers it as a defined lode, believing that recent developments, at various points, have a tendency to confirm this theory.

The most southerly well-defined outcrop of this remarkable vein is at the Pine Tree and Josephine mines, or the Mariposa estate, at an elevation of about 2,500 feet above sea-level. From this point it takes a northwest direction, striking across the numerous spurs of the Sierras which form the divides between the Tuolumne, Stanislaus, and Moke

* Since writing the above, I learn that operations have been resumed on the Unica Mine, at Copperopolis.

lumne Rivers and their tributaries, and terminates in the foot-hills of Amador County, the most northerly deep-developed claims being the original Amador and Keystone at Amador City, although many locations between these mines and the Cosumnes River are supposed to be on the same lode. Beyond the Cosumnes the lode is not traceable.

Between its southern and northern extremities it is frequently broken up and lost, (invariably so at the intersection of the principal rivers,) making its appearance again at a distance of several miles, frequently in the form of a solid wall of quartz on the summits of isolated hills on the line of its strike, these croppings being visible for many miles. The most prominent of these hills are Piñon Blanco, Quartz Mountain, Whisky Hill, and Carson Hill. At these points the lode has widened with the "blossom" of the mountain, and presents the appearance of a system of parallel veins separated on the surface, and to an indefinite depth, by "horse" matter, composed of nearly equal parts of slate and broken quartz. Locations have been made in the majority of such instances on the croppings, parallel to each other, one on the hanging wall and another on the foot-wall of the lode, these walls being sometimes separated, as at Quartz Mountain, Tuolumne County, by a distance of from 200 to 250 feet; but recent deep developments at various points would seem to indicate a tendency of these walls to narrow, which, at depths of from 1,000 to 1,200 feet, and in some cases less, would shut out the "horse" and develop a permanent fissure of from fourteen to eighteen feet in width.

The principal points at which mining has been prosecuted on the Mother lode, are Bear Valley, Princton, and Mariposa, in Mariposa County; Quartz Mountain and vicinity, near Jamestown, Tuolumne County; Rawhide and Tuttletown, in same county; Carson Hill, Angel's Camp, and Paloma, in Calaveras County; and Jackson, Sutter Creek, and Amador City, in Amador County; the deepest development having been made at Sutter Creek, where, at the Amador mine, a shaft has been sunk, and levels opened to a depth of 1,300 feet.

The entire length of locations made on the Mother lode is estimated at 180,000 feet, equal to half the distance between its northern and southern extremity. Many of these locations, however, run parallel to each other, and the ground continuously located would not exceed 100,000 feet, while the ground now in process of development (including only those claims on which work has been done in 1871) will not exceed 40,000 feet, exclusive of the Mariposa estate, on which operations are temporarily suspended owing to financial difficulties and litigation.

The longest break of the lode is between Angel's and Jackson, a distance of twenty-three miles, on which only one mine, the Paloma, near the south bank of the Mokelumne River, is generally acknowledged to be on the lode, though recent discoveries tend to prove the continuity of the lode between these points. At various other points the lode "dives" for several miles, and at one point, between Whisky Hill and the Rawhide mine, it is covered by the lava flow which constitutes Table Mountain.

Throughout the entire course of the lode we find many instances of failure, manifested by abandoned works and idle mills, but these are to be attributed either to mismanagement or to the injudicious location of works at points where no pay-chimneys exist. The early locations were made at any point where croppings appeared, and deep shafts were sunk, and mills erected on barren ground, without any effort to find the chimneys of the vein. In this way thousands of dollars have been uselessly squandered by men utterly ignorant of mining, and these H. Ex. 211— 4