Note 21 — Chapter XVII · VOYAGE FROM FORT UNION TO MUSCLESHELL RIVER, FROM THE 6TH TO THE 28TH OF JULY

Probably Red Water Creek, just above Poplar River, but on the south, not north, side of the Missouri. In the Original Journals, both Lewis and Clark speak of this creek as on the "larboard side." There is some reason to think that Maximilian was mistaken in his identification of these three rivers of Lewis and Clark—Martha's, Porcupine, and Two Thousand Mile Creek. The one called by him Martha's, or La Rivière aux Trembles, was probably the present Poplar, which would correspond to the French-Canadian name; but this was not the river named Martha's by Lewis and Clark (see ante, note 16). Maximilian speaks of Porcupine River as a "small stream," while in reality it was the largest river passed above the Yellowstone, and Lewis and Clark considered it as a possible line of communication with the Saskatchewan. Maximilian's "Porcupine" would thus be either Tulle Creek, or some of the smaller northern affluents of this stretch of the river, which would also account for his misplacing Two Thousand Mile Creek.—Ed.