284 EXPEDITION OF LEWIS AND CLARKE TO THE WEST. [1S05. 



his suggestions having been approved, he commissioned Captains 

 Meriwether Lewis and William Clarke to explore the River Mis- 

 souri and its principal branches to their sources, and then to seek 

 and trace to its termination in the Pacific, some stream, " whether 

 the Columbia, the Oregon, the Colorado, or any other, which might 

 oner the most direct and practicable water communication across 

 the continent, for the purposes of commerce." Other persons 

 were, at the same time, appointed to examine the Upper Mississippi, 

 and the principal streams falling into that great river from the west, 

 below the Missouri, in order that exact information might, as soon 

 as possible, be procured, with regard to the channels of communi- 

 cation throughout the newly-acquired territories. 



A few days after Lewis had received his instructions as com- 

 mander of the party which was to cross the continent, the news of 

 the conclusion of the treaty for the cession of Louisiana reached 

 the United States ; and he immediately set off for the west, with 

 the expectation of advancing some distance up the Missouri before 

 the winter. He was, however, unable to pass the Mississippi in 

 that year, in consequence of the delay in the surrender of the 

 country, which was not terminated until the latter part of Decem- 

 ber; and it was not until the middle of May, 1804, that he could 

 begin the ascent of the Missouri. His party consisted of forty-four 

 men, who were embarked in three boats ; their progress against the 

 current of the mighty river was necessarily slow, yet, before the 

 end of October, they arrived in the country of the Mandan Indians, 

 where they remained until the following April, encamped at a place 

 near the 48th degree of latitude, sixteen hundred miles from the 

 Mississippi. 



On the 7th of April, 1805, Lewis and Clarke left their encamp- 

 ment in the Mandan country, with thirty men, the others having 

 been sent back to St. Louis ; and, after a voyage of three weeks up 

 the Missouri, they reached the junction of that river with the other 

 principal branch, scarcely inferior in magnitude, called by the old 

 French traders the Roche jaune, or Yellowstone River. Thence 

 continuing their progress westward on the main stream, their navi- 

 gation was, on the 13th of June, arrested by the Great Foils of the 

 Missouri, a series of cataracts extending about ten miles in length, 

 in the principal of which the whole river rushes over a precipice of 

 rock eighty-seven feet in height. Above the falls, the party again 

 embarked in canoes hollowed out from the trunks of the largest 

 cotton-wood trees, growing near the river ; and, advancing south- 



