37 x 49 cm. Relief shown by hachures and spot heights. Prime meridians: Greenwich and Washington, D.C. "Atlas sheet no. 70(A)." "Issued May 7th, 1877." "Expeditions of 1874, 1875 & 1876 under the command of 1st. Lieut. Geo. M. Wheeler, Corps of Engineer, U.S. Army." "Weyss, Herman & Mahlo, del." "By order of the honorable the Secretary of War." "Under the direction of Brig. General A. A. Hunphreys, Chief of Engineers, U. S. Army." Original publisher: U.S. Geographical Surveys West of the 100th Meridian, Scale: 1 inch to 4 miles or 1: 253440.