The Deep Lying Auriferous Gravels and Table Mountains of California (Classic Reprint)

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Excerpt from The Deep Lying Auriferous Gravels and Table Mountains of California The object of this paper is not to disprove the opinions of others, but to record some of the results of my study of a very interesting subject, and perhaps to add something to a controversy still claiming the attention of geologists. It has not been written at random, but by request from a source worthy of consideration, at a time when I had the leisure and inclination to comply, and I have selected from a gathering of many years such facts and theories as I thought might be of general interest. The placer gold mines of California are by nature divided into two general classes, the shallow and the deep, the former were first discovered and worked, when the gold crop diminished, prospecting tunnels were driven into low "table mountains, " revealing extensive and rich deposits, and a new system, called "drift mining, " followed. Some of these adit levels were more than a mile in extent. In many cases shafts were sunk from the surface several hundred feet in depth, from the bottom of which tunnels were driven in search of gold. These tables cover strata of undoubted sediments varying in texture from bowlders weighing tons, to silts, so finely divided that they will not wholly settle in still water for several days. These are the "auriferous gravels" described by Professor Whitney and others. Since the discovery of gold in them they have been called "deep placers, " in contradistinction to "shallow" or surface placers, under table mountains, they have remained intact since the time of their placement. Elsewhere, not so protected, they have been subjected to more recent vicissitudes of nature, uncovered in places and again buried, crosscut by cations born of mountain torrents, shifted and disturbed many times until they have somewhat lost their original character, the result of which is the shallow placers from which so vast an amount of gold has been gathered by panning, by ground sluicing, and finally by hydraulic washing. I find the following among my historical notes: "In 1852 Mr. A. Bateman, in Tuolumne county, was engaged in placer mining, he and associates followed outcropping gravel under Table Mountain and discovered a dipping rim rock. He believed this tunnel to be the first one driven." About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.