They were "certainly the most gigantic men we have ever seen," Jefferson wrote to Secretary of the Treasury Albert Gallatin on 12 July 1804. A dozen Osage men and two boys, the first of three Indian delegations to visit Mr. Jefferson during his two administrations, had arrived in Washington City the previous day, escorted by Peter Chouteau, a prominent St. Louis fur trader and the government's first agent to the Osages.
In his paraphrase of the captains' journals, Nicholas Biddle somewhat expanded Clark's journal entry concerning the event that took place early on the morning of August 11, 1804. The boats came to at the foot of a hill on the west side of the Missouri River some eight miles northwest of Blue Lake, Iowa. The two captains and ten of the enlisted men climbed the hill to visit the grave of one of the most notorious and controversial leaders of the Omaha Nation, whose name was Washinga Sahba—Blackbird.
The visit to Spirit Mound was among the more bizarre sidelights of the whole expedition, but evidently it was not entirely unexpected. Seventy-six years earlier, explorer Pierre La Véndrye called the place the "Dwelling of the Spirits" and reported sparkling stones and gold-colored sand . . . .