WEED, Walter Harvey, American geolo gist: b. Saint Louis, Mo., 1 May 1862. He was graduated as mining engineer from Columbia University, School of Mines (1883) and ap pointed assistant geologist, United States Geo logical Survey in that year. In 1883-89 he was engaged in Yellowstone Park investigating hot springs and geysers, and glacial and sedimen tary formation. To him is due the discovery that the brilliant coloring about hot springs and geysers are not mineral but due to living alga; and he also found and described Death Gulch. He also made the discovery that Death Gulch gave out carbon dioxide gas from an extinct hot spring, and it was this that killed wild ani mals that strayed there. He was occupied in general geologic exploration work in Mon tana, 18139-98. His most notable contribu non to science was the theory of second ary enrichment of mineral deposits published in 1890, now generally accepted. This was followed by the theory of enrichment by as cending alkaline waters. He was one of the first to describe contact metamorphic ore de posits, and to interpret replacement deposits correctly. He is a member of practically all
important scientific societies and was appointed special expert and commissioner on copper for 1.c.uisiana purchase exposition, 1904. In 1906 he resigned from United States Geological Survey to become chief geologist and examining engi t,eer for General Development Company, and in 1010 went into private practice as consulting engineer and mine valuer. In recent years he has been expert witness in many important mining lawsuits_ His publications include 'Copper Mines of the World' ; 'Nature of Mineral Deposits' (a textbook, a revision and translation of Beck's German treatise) - 'Geol ogy of Butte, Montana': 'Geysers': 'Second ary Enrichment': and many papers of the United States Geological Survey and in 'Trans actions' of the American Institute Mining En gineers, and the technical journals