Prepared to accompany the report of Thomas Antisell M.D., geologist of the expedition. "U.S. Pacific rail road expl. & surveys, War Dept., no. 2." Latitude lines are not identified on the map. Includes a cross section of the same area. State/territory lines not included. 1 map: hand color; 22 x 60 cm, on sheet 39 x 65 cm