When 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 cross -- existing 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 maps detailing with remarkable accuracy the features of the country that they had traversed.

Volumes 2-7: Gary E. Moulton, editor; Thomas W. Dunlay, assistant editor.

Volume 1 : Atlas of the Lewis & Clark Expedition -- Volume 2 : August 30, 1803-August 24, 1804 -- Volume 3 : August 25, 1804-April 6, 1805 -- Volume 4 : April 7-July 27, 1805 -- Volume 5 : July 28-November 1, 1805 -- Volume 6 : November 2, 1805-March 22, 1806 -- Volume 7 : March 23-June 9, 1806 -- Volume 8 : June 10-September 26, 1806 -- Volume 9 : The journals of John Ordway, May 14, 1804-September 23, 1806, and Charles Floyd, May 14-August 18, 1804 -- Volume 10 : The journal of Patrick Gass, May 14, 1804-September 23, 1806 -- Volume 11 : The journals of Joseph Whitehouse, May 14, 1804-April 2, 1806 -- Volume 12 : Herbarium of the Lewis & Clark Expedition -- v. 13. Comprehensive index.