History of Amador County, California: With Illustrations and Biographical Sketches of Its Prominent Men and Pioneers. E-book. Formato PDF Jesse D. Mason   -  Forgotten Books, 2017  - 

The chapters on geology and mining,' will, it is hoped, furnish interesting and profitable reading to all, especially those engaged in mining. The facts and theories are the result of years of Observation, and many miles of travel, and are not retailed at second hand from W'hitney or other scientists. The Observations on mining have been compiled from the statements, Opinions and experiences, of hun dreds of intelligent miners. Thanks are due to all the superintendents, especially to those of the Ama dor Consolidated, the Keystone, the Oneida, the Empire, the Downs and the Zeile mines for valuable information on gold mining, and to Edward Johnson of the Newton mine, for statistics and methods of copper mining.