"Map of a Reconnaissance for a Military Road from the Dalles of the Columbia River to Great Salt Lake under the command of Capt. H.D. Wallen. 4th Inf. By Lieut. Joseph Dixon, T. Engrs", U.S. War Department
Subject: Western United States
Period: 1859 (dated)
Publication: Sen. Doc #34, 36th Congress, 1st Ses.
Detailed map of the region between Mt. Hood and the Great Salt Lake. Shows the Snake River drainage in detail. Forts Wallah Wallah, Dalles, Boise and Hall are shown along with wagon roads and proposed routes. Locates many geographical features, and shows L. Scholl's route of the same year. Excellent topo and watershed detail.