At top of map: 'Reconnaissance Maps, Department of California.' In lower right corner: 'Photolith. by the N.Y. Lithg. Engrg. & Prtg. Co.' 'In charge of, Lieut. Geo. M. Wheeler, U.S. Engineers; assisted by Lieut. D.W. Lockwood, Corps of Engineers,U.S.A., 1969.' 'P.W. Hamel, chief topographer and draugthsman.' 'Officially compiled and published at the Engineer Office, Head Quarters Department of California in 1869 and 70 by order of Brigadier General E.O.C. Ord. Comm'dg. [signed] Geo. M. Wheeler, Lieutenant of Engineers In Charge, Head Quarters Dept. of Cal. Oct. 26th, 1870.' Includes information from railroad maps, the United States Geological Survey of the 40th parallel and from Lieutenant Ives' explorations along the Colorado. Map includes camps, astronomical stations, good and bad wagon roads, trails, springs, settlements, mining districts, state and county boundaries and the watershed between the Humboldt and Colorado Basin. Shows most of eastern half of Nevada. Relief shown by hachures and spot heights. Scale: [1:760,320]. 1 in. to approx. 12 miles. (W 117°00´--W 113°00´/N 41°45´--N 35°45´). Series: Reconnaissance maps. Military map / Department of Californiano. 1.miles. Library's copy has counties hand-outlined in colored markers.