Of the Columbia[4] nothing certain was known. More was known, even in America, about the Nile. It was thought, however, that its highest streams would be found interlocked with those of the Missouri, about the feet of the same great mountain chain. Should this prove true, a practicable passage from one to the other through these mountains might be discovered; yet while nothing actual was known about them the difficulties were felt to be so uncommon, that none but men of tried courage would be found equal to them. Clearly it was to be no holiday journey. Just what obstacles lay in the explorer's way, what means of living the country would afford, what sort of people would be met with, were questions no one had so far attempted to solve. Mr. Jefferson set about solving them. He looked about him for the man to do the work. His first choice fell upon his own secretary, Captain Meriwether Lewis,[5] "of courage undaunted," at whose request Captain William Clarke[6] was invited to make one of the party. Clarke accepted the offer with great glee. Both were young men, both had seen service on the frontiers, both were Virginians, and both gave heart and soul to the enterprise in hand. Though its objects were less scientific than political, the young explorers were commanded to carefully note down every thing of interest about the countries and nations they were going to pass through—what were the natural products of the one, or the numbers, disposition and manners of the other. It was to be a long voyage to begin with—two thousand miles at the least. The best the Government could do was to provide a keel-boat, fifty-five feet long, drawing three feet, carrying one large square sail and twenty-two oars. A half deck at bow and stern formed forecastle and cabin, the middle being left open for the rowers. This vessel, we see, was but a modification of the galley of ancient times, and quite like those used by the Spaniards in exploring our coasts two centuries before. Thus equipped the party started down the Ohio on their long journey to the Pacific. The Spaniards had not yet given up St. Louis to us when the expedition reached there, in the autumn of 1803. It therefore went into winter quarters on the American bank of the Mississippi, opposite the mouth of the Missouri. [Illustration: A MANDAN.] It was the middle of May before the voyage up the Missouri could begin. With sail and oars, the deeply laden keel-boat was forced slowly along against a swift yellow tide, which ever and anon hurled floating trees athwart its course, or brought it to a standstill on some hidden sand-bar. Compared with it, the navigation of the Ohio was but a pleasure-trip. The Platte, however, was reached late in July. Not far above, the explorers landed to hold a council with the Otoes, for which reason they gave the place the name of Council Bluff.