Public domain
Science and research. Studies of non-coking coals. V.F. Parry, supervising engineer of the Golden, Colorado field station of the U.S. Bureau of Mines is "sighting a coke bubble." This procedure is used to determine if a given coke has changed its properties or it is similar to another coke. One gram
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Credit lineScience and research. Studies of non-coking coals. V.F. Parry, supervising engineer of the Golden, Colorado field station of the U.S. Bureau of Mines is "sighting a coke bubble." This procedure is use. 1942-01-01. United States. Office Of War Information, Feininger, Andreas. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.