Outline sketch map of the United States west of the Mississippi River designed to show the relationship of the proposed railroad routes. First edition of the map appears in U.S. War Department, Report of the Secretary...Communicating the Several Pacific Railroad Explorations (Washington, 1855). [From published bibliography]
Very detailed map of the United States west of the Mississippi River indicating drainage, relief by hachures, cities and towns, forts, trails, wagon roads, and routes of exploration. An important map of western expansion, it utilized and lists 45 major exploration and mapping reports from the Lewis & Clark to the U.S. General Land Office Surveys.