During the winter at Fort Mandan, Clark drew the above sketch from information provided by the Mandan chief, Sheheke, or "Big White," who dined with the captains on January 7, 1805, and gave him "a Scetch of the Countrey as far as the high mountains, & on the South side of the River Rejone [Roche Jaune; Yellowstone]." Clark added, "he Says that the river rejone recves 6 small rivers on the s. Side, & that the Countrey is verry hilley and the greater part Covered with timber, Great numbers of beaver &c." Gary Moulton has concluded that some of the tributaries were added to the map after Clark covered the route in 1806.1
The comprehensive map Clark compiled at Fort Mandan that winter shows "The War Path of the Big Bellies Nation" extending westward from the mouth of the Knife River and crossing the Yellowstone at the mouth of O'Fallon Creek (Coal Creek, or Oak-tar-pon-er). It is impossible to say whether this was supposed to be identical with the route shown on Sheheke's map, because Clark drew both from Indian information before he explored the ground personally.
1. Moulton, ed., Atlas, map 31b.