Public domain
Science and research. Mineral prospecting. Speed in metallurgical analysis, to match the rapidity with which the nation arms itself, is possible through use of the spectrograph, a marvelous new machine used for study of materials through measurements of the arc of light they emit when heated. The al
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Credit lineScience and research. Mineral prospecting. Speed in metallurgical analysis, to match the rapidity with which the nation arms itself, is possible through use of the spectrograph, a marvelous new machin. 1942-01-01. United States. Office Of War Information, Feininger, Andreas. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.
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