It is plain that this astute judge of men reposed perfect confidence in his friend. From January, 1803, when Congress sanctioned the undertaking, until May, 1804, when the party set out from St. Louis, the young officer had full charge of the intricate and difficult details of preparation. It was he who superintended the building of boats and the making of arms, accoutrements, scientific apparatus, and all equipment; and, what was of more importance, he selected the men who were to form his command. That was a nice matter. It would have been worse than useless to lead a company of fretful dissenters. The expedition was to be conducted on a military basis; but it was not ordinary field service; it was a mission for picked men. Much would depend upon each man's natural aptitude for his task; much more would depend upon the integrity of the corps as a whole. The consummate wisdom of Lewis's selection of his aids shines from every page of the journals. None of the men seemed to need instruction in the cardinal elements of conduct; each was as sensible of his trust as Lewis himself. It was in this spirit of the subordinates, rather than in the absolute authority of the captain, that success was to lie. To guard against untoward accident, that might thwart the work, Lewis wished to have a companion in command. This pleased Mr. Jefferson, and the choice fell upon Captain William Clark. William Clark was the ninth of a family of ten children. His father was John Clark, second, who, like his father before him, was a Virginian, living in King and Queen County. The pioneering spirit was strong in the family,--the _Wanderlust_, that keeps man's nature fluid and adaptable. This led John, second, to remove first to Albemarle County, and later to Caroline County, where William was born on August 1, 1770, not far from the birthplace of Meriwether Lewis. When the boy was about fourteen years of age, the family moved once more, into the dim West, settling at the place now known as Louisville, in Kentucky. William's elder brother, George Rogers Clark, had preceded the others, and had built the first fortification against the Indians at the Falls of the Ohio, around which were clustered a few of the rude dwellings of the frontiersmen. At this place, amidst the crudest conditions of the Kentucky border, the lad grew to maturity. That was not an orderly life; it was rather a continuing state of suspense, demanding of those who shared in it constant hardihood and fortitude. For the right-minded man, however, it had incalculable value. Many of the strongest examples of our national character have been men who owed the best that was in them to the apparently unkindly circumstances of their youth. What was denied to Clark in easy opportunity had ample compensation in the firmness and self-reliance which came from mastering difficulties.