The yearly production of gold in the United States, by States, from 1914 to 1917, is as fol lows: and which has attained a depth of 5,900 feet, vertically.
From the 4th to the 15th centuries or alchemy, flourished and was busied in the attempt to transmute base metals into gold and silver. The alchemists, though they failed in their main object, laid the foundations for the science of chemistry and improved the metal lurgy of the metals. The gold seekers have been instrumental also in the discovery and opening up of lands in new countries and the spreading of knowledge. The gold miner has blazed the trail for civilization in many lands. It has been well said, follows the flag, it is true, but the flag follows the pick.) Bibliography.— Mining and Mode of Occur rence and Distribution of Gold: Emmons, S. F., and Becker, G. F., Metals' (Vol. XIII of Census Reports of 1880, Wash ington 1:::5); Foster, C. LeN., 'The Ele ments of Mining and Quarrying> (1903 ; Hoover, H. C., 'Principles of Mining> (1909 ; Lindgren, W., 'Mineral Deposits> (1913 ; The richest gold and silver lode in the world was the Comstock Lode, which opened in 1859 and worked extensively for 30 to 35 years, and produced over $470,000,000, of which about $190,000,000 was gold. The work ing costs were very high. Mount Morgan Mine, in Queensland, is a great gold and copper deposit. It was started as a gold mine in 1882 as an open-cut working, in a siliceous gossan capping of a copper sulphide deposit. It is now being largely exploited for copper. It has yielded in dividends about $43,000,000. Its costs have been high. The Waihi Gold Mine, in New Zealand, started in 1887, is still work ing, and has yielded over $30,000.000. It was one of the first mines to successfully use the cyanide treatment. The Mysore mine in India has worked since 1880, has been a big producer for a narrow lode and is still operating with shafts over 4,000 feet deep. The deepest and longest-worked gold mine in the world is the Saint John del Rey, Brazil, worked since 1830, Lindgren, W., and Ransome, F. L., 'Geology and Gold Deposits of Cripple Creek District, Colorado' (U. S. Geological Survey, Pro fessional Paper No. 54, 1906) ; Lock, C. G. W., 'Economic Mining' (London 1895) ; Maclaren, J. M., 'Gold: its Geological Occur rence and Geographical Distribution> (London 1912) ; American Institute of Mining Engineers, Special Volume, 'Genesis of Ore-Deposits> by Posepny, Le Conte, Vogt, Kemp, Rickard, Van Hise, Emmons, Lindgren, Weed and others (1901) ; id., 'Volume on Ore Deposits' by S. F. Emmons and others (New York 1915).
General Metallurgy of Gold: Agricola, Georgius, 'De re Metallica> translated from Latin edition of 1556, by H. C. and L. H. Hoover (London 1912) ; Charleton, A. G., 'Gold Mining and Milling in Western Australia' (London 1903) ; Eissler, M., 'The Metallurgy of Gold> (5th ed., London 1900) ; Fulton, C. H.,
'Principles of Metallurgy' (New York 1910) ; Gowland, Wm., 'Metallurgy of the Non-Fer rous Metals) (London 1914) ; Hatch, F. H., and Chalmers, J. A., (Gold Mines of the Rand' (London 1895) ; Launay, L. de, (Les Mines d'Or du Transvaal) (Paris 1896) ; Lock, A. G., Its Occurrence and Extraction' (with a bibliography, London 1882) ; Lock, G. W., (Practical Gold (London 1889) ; Percy, John, (Metallurgy of Silver and Gold' (Vol. I, London 1880) ; Rand Metallurgists, 'Text-Book of Rand Metallurgical Practice) (2 vols., 2d ed., 1913) ; Richards, R. H., Dressing) (2 vols., 1903) ; id., 'Text Book of Ore Dressing' (New York 1911) ; Rickard, T. A., (Variations in Gold-Milling) (New York 1895) ; Rose, T. K., (The Precious Metals, comprising Gold, Silver and Platinum) (Lon don 1909) ; Rose, Sir T. K., (The Metallurgy of Gold) (1915).
Placer Mining:—Bowie, A. J., Jr., (Practi cal Treatise on Hydraulic Mining in Califor nia) (New York 1885) ; Janin, Charles, (Gold Dredging in the United States' (Bureau of Mines, Bull. 127, 1918) • Jennings, H., (History and Development of Gold Dredging in Mon tana' (Bureau of Mines, Bull. 121, 1915) • Long ridge, C. C. (Hydraulic Mining) (London 1903 and 1905); id., Dredging' (London 1905) ; Purington, C. W., (Hydraulic Elevator Work on Anvil Creek, Nome, Alaska' (London 1913) ; Weatherbe, D'Arcy, (Dredging for Gold in California) (San Francisco 1907) ; Whitney, J. D., (Auriferous Gravels of the Sierra Nevada of California' (Cambridge, 1880).
Cyanide Process: Bain, H. Foster, Recent Cyanide Practice' (San Francisco 1910) ; Clennell, J. E., 'Cyanide Handbook' (New York 1910) ; id., of Cyanide Solu tions resulting from the Treatment of Ores' (2d ed., New York 1910) ; Fulton, Chas. H., Cyaniding Process in the Black Hills, South Dakota' (Bull. 5, S. Dak. School of Mines, 1902) ; James, A., (Cyanide Practice' (3d ed., London 1903) ; Julian, H. F., and Smart, E., 'Cyaniding Gold and Silver Ores,' (2d ed., Lon don 1911) ; MacFarren, H. W., (Cyanide Prac tice' (New York and London 1912) ; Park, Jas., (The Cyanide Process of Gold Extraction' (Auckland and Melbourne 1896; London, 5th ed., 1913) ; Rickard, T. A., Cyanide Practice) (San Francisco 1907).
Statistics of Gold Production and Consump tion: Launay, L. de, (The World's Gold' (translated by O. C. Williams, London 1908) ; (Mineral Resources, United States' (U. S. Geological Survey, Washington, D. C.) ; Soet beer, A., (Materialen zur Erlauterung and Bcurteilung der wirtschaftlichen Edelmetallver haltnisse and der Wahrungsf rage' (Berlin 1886) ; Annual Reports of the Director of the Mint (Washington, D. C.) ; Annual Reports of the Royal Mint (London) ; Reports of Chamber of Mines of Transvaal.
Flotation Process:— Rickard, T. A.. and Ralston, O. C., (Flotation) (Mining and Scien tific Press, 1917).