Series IX. Photographic prints, negatives, slides, and glass plate negatives, approximately 1900 to 1974

The photographic prints, negatives, slides, and glass plate negatives series (1900-1974) consists of black-and-white and color prints and negatives of geological features, predominately in southern Nevada, California, and Arizona but including other locations in the United States, Europe, and Asia. Also included are photographs taken of the moon by the Mt. Wilson Observatory telescope, numerous negative albums, photographic slides used for instructional purposes, glass plate negatives, and several letters and documents associated with the photographic prints.