Lewis and Clark’s Corps of Discovery was the first major expedition launched by the United States to explore new lands with an emphasis on scientific inquiry. Lewis spent months being tutored in both physical and biological sciences in preparation for the expedition, and Jefferson instructed Lewis and Clark to bring home scientific, anthropological, and geological information and to record their observations with great pains and accuracy, making multiple copies of their notes to guard against accidental loss. Many plants and animals familiar to American Indians in the West were unknown to people in the eastern United States before the Lewis and Clark Expedition in 1804, and Jefferson even instructed Lewis to watch for mastodons. The expedition kept detailed journals of new species they observed and sent bird skins, furs, and even live animals—four magpies, one sharp-tailed grouse, and one prairie dog—from Fort Mandan, North Dakota, back to Jefferson in Washington, D.C. The expedition camped here on September 12, 1805.