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Interior Dept. - Bureau of Mines, [Washington, DC], between 1910 and 1920. Scientist using a bunsen burner to heat a glass instrument. The United States Bureau of Mines (USBM) was the primary US government agency conducting scientific research and disseminating information on the extraction, processing, use, and conservation of mineral resources. Interior Dept. - Bureau of Mines, between 1910 and 1920. Creator: Harris & Ewing. (KEYSTONE/HERITAGE IMAGES/HERITAGE ART)