# The New International Encyclopædia/Lewis and Clark Expedition

Edition of 1905. See also Lewis and Clark Expedition on Wikipedia; and the disclaimer.
​LEWIS AND CLARK EXPEDITION. In American history, an expedition, under the command of Meriwether Lewis (q.v.) and William Clark (q.v.), which in 1804-06 penetrated from the Mississippi River, through territory now forming parts of Missouri, Kansas, Nebraska, South Dakota, North Dakota, Montana, Idaho, Washington, and Oregon, to the Pacific Ocean. The members of the party were the first white men to cross the continent between the Spanish possessions to the south and the British possessions to the north. The expedition was sent out by President Jefferson for the purpose of exploring the Louisiana Territory, immediately after its purchase from France. As at first organized the party consisted of 29 members: Lewis and Clark, 14 regular United States soldiers, 9 Kentuckians who had vohmteered. 2 French watermen, an interpreter and hunter, and a negro servant. At Saint Louis sixteen additional men were enlisted for the enterprise, to go, however, only part of the way. The party started from the vicinity of Saint Louis, Mo., on May 14, 1804; passed up the Missouri River; reached the mouth of the Platte on July 26th; arrived at the camps of the Mandans and Minnetarees, about 1000 miles distant from Saint Louis, late in October; wintered there; broke up winter quarters April 7, 1805, 14 men having been sent hack to Saint Louis with collections and reports and two recruits having been gained; reached the mouth of the Yellowstone River, April 26th; and on May 26th sighted the Rocky Mountains. The three forks of the Missouri River were discovered on July 25th, and named Jefferson, Madison, and Gallatin. The party proceeded up the Jefferson; crossed the Rocky Mountains in September; started down the Columbia River on October 16th; and on November 7th came in sight of the Pacific Ocean. After wintering on the coast, they started on their return, March 23, 1806, and arrived at Saint Louis September 23, 1806, having traveled altogether a distance of almost 8500 miles. At times the explorers suffered terrible hardships, and from April, 1805, to August, 1806, were shut off from all communication with the world. Lewis and Clark collected a mass of valuable information concerning the physical characteristics, the fauna and flora, the climate, and the various Indian tribes of the territory traversed. For accounts of the expedition, consult: Jefferson, Message from the President of the United States, Communicating Discoveries Made in Exploring the Missouri, Red River, and Washita by Captains Lewis and Clark, Dr. Sibley, and Mr. Dunbar (Washington, 1806; various subsequent editions); Gass, A Journal of the Voyages and Travels of a Corps of Discovery Under the Command of Captain Lewis and Captain Clark (Pittsburg, 1807; several subsequent editions); and especially Allen (Biddle ed.), History of the Expedition Under the Command of Captains Lewis and Clark to Sources of the Missouri, Thence Across the Rocky Mountains and Down the River Columbia to the Pacific Ocean (2 vols., Philadelphia, 1814), which is based on the journals kept by Lewis and Clark themselves, and has been frequently reprinted, the best edition being the one edited by Coues, History of the Expedition Under Lewis and Clark (4 vols., New York, 1893). Consult also: Brooks (ed.), First Across the Continent: Expedition of Lewis and Clark (New York, 1901); and a brief sketch by Lighton, Lewis and Clark (Boston, 1901), in the “Riverside Biographical Series.”