Archival objects in this container: Hoover Dam's downstream face, approximately 1936-1940 Hoover Dam's downstream face, approximately 1936-1940 Hoover Dam's downstream face at night, approximately 1936-1940 Hoover Dam's downstream face at night, approximately 1936-1940 Hoover Dam with rainbow over the Colorado River, approximately 1936-1940 Lake Mead behind Hoover Dam, approximately 1936-1940 Hoover Dam, approximately 1936-1940