Explorations and surveys south of Central Pacific R.R., War Department : preliminary topographical map embracing in skeleton a portion only of the notes from surveys made in accordance with Par.II Special Orders No. 109 War Dept., March 18th, 1871 and letUnited States. Army. Corps of Engineers1872?]"Note: This map is a hasty and partial compilation from the topographical data already received, many still remaining en route."In upper margin: ExplorationsPreliminary report of explorations in Nevada and Arizona. 1872.cartographic