Early in October the travelers entered the districts occupied by the Mandans, a native tribe holding some very peculiar notions with regard to the powers of the Great Spirit, whom they also called the Great Medicine, recognizing his agency in every cure of ill, whether physical, mental or temporal. Unfortunately, in spite of this strangely advanced creed, the Mandans were a degraded and dissolute race, ready to give and equally ready to take offense; the tomahawk being the usual weapon resorted to for revenge. In spite of the unpromising character of the people among whom they found themselves, the American leader resolved, as the season was now so far advanced, to build a fort in the Mandan country in which to spend the winter, and to resume their task with fresh ardor in the ensuing spring. The friendship of the Mandans and of the Minnetarees, dwelling in the highlands of Minnesota on the east, was conciliated by presents, etc., and a site chosen for the fort in N. lat. 47°. Aided by the advice and assistance of a number of the English Hudson’s Bay Company, and of a Canadian Frenchman who had spent some time among the Cheyenne Indians, the soldiers quickly constructed, not only a fort for their protection, but a number of cabins for their comfort; and the whole of the winter was passed in studying the ways of the natives, hunting, etc., the monotony of the residence in the spot being often relieved by visits from French or Canadian fur-traders, from whom much valuable information was obtained. Early in April of the ensuing year, 1805, the camp at Fort Mandan, as the temporary settlement had been called, was broken up, and the party, now numbering thirty-two, and with their means of navigation increased to eight boats and canoes, once more embarked on the Missouri. To aid in intercourse with the Shoshone or Snake Indians of Montana, Idaho, and Oregon, two interpreters were secured, namely, George Drewyer and Toussaint Chabornæan, the latter of whom was accompanied by his wife, a young Snake woman who had been taken prisoner by his tribe some time before. Illustration: YELLOWSTONE LAKE.