1. A map of Lewis and Clark's track, across the western portion of North America from the Mississippi to the Pacific Ocean; by order of the executive of the United States in 1804, 5 & 6. Maps Pennsylvania State University Public content 1964. Lewis, Samuel, 1753 or 1754-1822. Lewis and Clark Expedition (1804-1806)--Maps. [Bradford and Inskeep], Iowa City, State Historical Society of Iowa.