The winter at Fort Mandan passed pleasantly. Corn and other supplies were bought from the natives, and there was plenty of game. About the middle of December, a trapper named Haney arrived from Montagne à la Basse with a note from Chaboillez, in reply to the one sent by Lewis to him. He offered to render any service in his power. Later the trader Laroche came again, desiring to go with the expedition, but Lewis declined his proposition. Laroche had previously planned a journey in that direction which he had not carried out. They had other visitors, among them McKenzie, one of the principal North-west men. The intercourse with the people of the North-west Company was entirely amicable, and there was no friction except for a brief time, when they tried to prevent the interpreter from continuing in Lewis and Clark's service, and took steps to prejudice the natives. This was not sanctioned, however, by Chaboillez or McKenzie.

On Sunday the 7th of April, 1805, all being ready, the party again took up its line of travel up the river. It now numbered thirty-two, the others having been sent back. The interpreters were Drewyer (Drouillard) and Chaboneau, both Frenchmen. Chaboneau took with him one of his three Amerind wives, one who had a small child. This woman Lewis and Clark hoped to utilise as an interpreter among the Snake tribe, to whom she belonged, having been taken captive by another tribe and finally sold to Chaboneau. Her name was Sacajawea, and she was of great assistance, notwithstanding the encumbrance of the child. After eight days they passed what they called Chaboneau Creek and Sunday Island. Chaboneau had once encamped on this creek. "Beyond this no white men had ever been but two Frenchmen," says the journal. One of these, Lapage, was with them, and he could not tell exactly how far he had gone, as they had lost their way. But Captain Lewis does not explain, if this were correct, how the Roche Jaune came to have its name before he reached it, a name which could have been applied only by some one who understood the conditions near its head. Yet farther on he states that this river "had been known to the French as the Roche Jaune, or as we have called it the Yellowstone." Proceeding up the Missouri they came to the "Musselshell," which is stated to have been so called by the Minitarees. The name then seems to have been a native word and has no connection with the shells of mussels! All through this region they saw large numbers of trees which had been cut down by beaver, and as they proceeded the beaver were thick everywhere. Buffalo were plentiful, and there was no dearth of fresh meat of all kinds. Sometimes they had to take sticks to drive the buffalo out of the way. There was one kind of game that was troublesome—the huge bears, both white (grizzly) and brown. If it be remembered that the guns of the party were muzzle-loaders, that the ammunition was loose powder and ball, that the firing apparatus was the old flint-lock, with priming-pan, it will be seen that it was no small hazard to face these ferocious bears. On one occasion six of the men, all good hunters, at the same moment attacked one of the huge brown bears, and though the bullets all took effect they were obliged to fly to the river, where two escaped in a canoe, while the others hid in bushes and fired repeatedly. The only effect of this was to enrage the animal still more till the four hunters were glad to leap down the steep bank twenty feet into the river, whither the bear pursued them and was within a few feet of one when a good shot from the shore hit him in the head and at last killed him. Eight balls had passed in different directions through him.

Canyon of the Gates of the Mountains.

From The Trail of Lewis and Clark, by O. D. Wheeler.

On May 26th, from the summit of a hill, Captain Lewis had the first sight of the Rocky Mountains, which seemed to be about fifty miles away. This was from a few miles below Judith River, and the mountains seen were probably the Belt range. They were not the first to see the Rocky Mountains. The French and the Spaniards had been to them farther south. They were surrounded by immense quantities of game from here on to the sources of the Missouri, and their larder was always full of dainties. The river was 150 to 250 yards wide, and they had no difficulty in ascending. There were many signs of the aboriginal owners of the soil, particularly old lodges. This was the country of the Minitarees, who had described it to the leaders. It seems singular that they did not secure two or three of these Amerinds as guides. Had they done so, they would have been spared a good deal of labour and considerable delay. As they toiled up the Missouri they came at length to a point where it was difficult to tell which of two branches to take—that is, which was the real Missouri,—but they finally made a correct decision, and, naming the northern branch Maria's River, continued up the left or southern stream, when they soon arrived at the Great Falls. Had Fidler come down as far as this it would seem that he would have discovered these falls and would have described them, hence as he seems not to have mentioned them it is probable that he did not come much below the branches of Maria's River, and that Lewis and Clark were now in the untrodden Wilderness, untrodden by whites with the possible exception of the Verendryes or some other Frenchman of that period.

A portage eighteen miles long was imperative to surmount the falls, and it was rendered more difficult by extremely hot summer weather. A large cottonwood, the only one of the proper diameter within miles, was felled for the purpose of sawing from its trunk wheels with which to make a carriage for transporting the canoes. Sacajawea had been seriously ill since leaving Maria's River and it was fortunate for the party that she recovered, a happy event largely assisted by draughts from some sulphur springs found here. Here too she, together with Captain Clark, his negro, and her husband, was nearly lost by the flood from a cloudburst, having encamped in a deep, dry ravine. Even to this day people have not learned to avoid camping in the Great West, in the bottoms of ravines and washes which in a few minutes may become filled by roaring torrents.