mines, whose development has but just commenced. This species of mineral riches lies in that region where the auriferous quartz has been discovered of nearly uniform richness, from the 40th to the 35th degree of latitude, upon the waters of the Feather river, and on the American, the Mokelumne, the Mariposa, and the desert upon the south-eastern borders of California, east of the Sierra Nevada. In all these localities, within a range of three hundred and fifty miles, it is already known to exist, and the strongest analogy would carry it through the remaining distance. An assay of the ore of the Mariposa mines, now worked with a Chilian mill, afforded an average yield from washing, of forty cents per pound avoirdupois; and afterwards, by the fine process, produced eighty cents to the pound additional; making one dollar and twenty cents per pound as the average. Other assays exhibit results from ores in various sections of California, ranging from twenty-five cents to five dollars per pound, and that, too, in specimens where no gold is visible to the naked eye. Rocks examined even within two miles of San Francisco, have yielded gold to the amount of ten cents per pound. The result at the Mariposa mine has been at the rate of two thousand five hundred dollars for every ton!
These facts, stated upon grave authority, may be regarded as positive information applicable to the whole extent of the gold producing quartz. If we apply the results of the working of a British mining company,—The San Juan del Rey,—in Brazil, to these assays and conclusions, we may estimate the consequences upon the destiny of California and of the world. The work of this British company has increased annually for twenty years, and its last report dates on the 1st of March, 1850. In this it is stated that 69,000 tons of ore were crushed and the gold extracted therefrom;—applying this to the average yield of the mines in California, the result would be over one hundred and seventy millions of dollars!4
Various speculations have been made as to the gross numerical summary of all these discoveries and labors in a broiling sun, in icy streams and