The Journals of the Lewis and Clark Expedition, Volume 1When the Corps of Discovery left the vicinity of St. Louis in 1804 to explore the American West, they had only sketchy knowledge of the terrain that they were to crossexisting maps often contained large blank spaces and wild inaccuracies. William Clark painstakingly mapped every mile of the journey, drawing from both direct observation and from the reports of Indians and a few fur traders. On their return Lewis and Clark directed the execution of new