1879. Jenney, Walter Proctor, 1849-1921.; Mahlo, Emil, 1851-1904.; Geographical and Geological Survey of the Rocky Mountain Region (U.S.). 1 in. = 4 miles. Relief shown by hachures and spot heights. "Geology of the Black Hills by Henry Newton E.M."--Upper right. Dimensions: 74 x 89... Dept. of the Interior, U.S.G. and G. Survey (Washington, D.C.).