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 / copied by Samuel Lewis from the original drawing of Wm. Clark ; NeeleLewis, Samuel, 1753 or 1754-18221814Includes text.Prime meridians: London and Washington.Relief shown by hachures.cartographic