This beautiful and costly skin, when its history is known, will furnish a striking proof of the importance which they attach to these propitiatory offerings. But a few weeks since, a party of Mandans returned from the Mouth of the Yellow Stone, two hundred miles above, with information that a party of Blackfeet were visiting that place on business with the American Fur Company; and that they had with them a white buffalo robe for sale. This was looked upon as a subject of great importance by the chiefs, and one worthy of public consideration. A white buffalo robe is a great curiosity, even in the country of buffaloes, and will always command an almost incredible price, from its extreme scarcity; and then, from its being the most costly article of traffic in these regions, it is usually converted into a _sacrifice_, being offered to the Great Spirit, as the most acceptable gift that can be procured. Amongst the vast herds of buffaloes which graze on these boundless prairies, there is not one in an hundred thousand, perhaps, that is white; and when such an one is obtained, it is considered great _medicine_ or mystery. On the receipt of the intelligence above-mentioned, the chiefs convened in council, and deliberated on the expediency of procuring the white robe from the Blackfeet; and also of appropriating the requisite means, and devising the proper mode of procedure for effecting the purchase. At the close of their deliberations, eight men were fitted out on eight of their best horses, who took from the Fur Company’s store, on the credit of the chiefs, goods exceeding even the value of their eight horses; and they started for the Mouth of the Yellow Stone, where they arrived in due time, and made the purchase, by leaving the eight horses and all the goods which they carried; returning on foot to their own village, bringing home with them the white robe, which was looked upon by all eyes of the villagers as a thing that was vastly curious, and containing (as they express it) something of the Great Spirit. This wonderful anomaly laid several days in the chief’s lodge, until public curiosity was gratified; and then it was taken by the doctors or high-priests, and with a great deal of form and mystery consecrated, and raised on the top of a long pole over the _medicine-lodge_; where it now stands in a group with the others, and will stand as an offering to the Great Spirit, until it decays and falls to the ground. This Letter, as I promised in its commencement, being devoted to some of the customs peculiar to the Mandans, and all of which will be new to the world, I shall close, after recording in it an account of a laughable farce, which was enacted in this village when I was on my journey up the river, and had stopped on the way to spend a day or two in the Mandan village.