Their objective was a point on the Saskatchewan about fifty miles above the present site of Battleford. As they continued their journey westward from Cumberland House, the forest gradually gave way to open country, and they found themselves in the vast expanse of the plains, dotted here and there with clumps of trees--the country of the bison, the antelope, and the red deer. Passing the forks of the river, they came to the site which the keen eye of Longmore had selected. There, on the northern bank of the stream, they cleared the ground and ran up a series of log huts, surrounded by a wooden stockade--the future Manchester House. Except for a solitary post which the North-Westers had for three years maintained about forty miles further up stream, Thompson had now reached the limit of country at that time familiar to civilized men. To the west stretched the unknown wilderness, which it was his destiny, in considerable measure, to explore. The object of the new post was to secure the trade of the natives of the plains; and during the following winter David was busy learning the complicated ritual of Indian barter. In the course of a year he had so far mastered his duties that he was selected to lead a party of six men across country to the south branch of the Saskatchewan, in order to open friendly relations with the Piegan and Blackfeet Indians whose camps lay along the banks of that stream. Each man had a horse, and among them they carried a small assortment of goods. The duties of the young diplomat were to find the camps of the Piegans and winter among them, in order to induce them to hunt for furs and to make pemmican or dried buffalo meat for the traders. He was to persuade as many as possible to travel to the post for trade. With those who were unwilling to do so, he was to bargain for furs. The party set forth in October, under their seventeen-year-old leader. The trail they followed led through a fine rolling country, everywhere clothed with short grass, and dotted with islands of poplar and birch. For twenty-three days they rode without seeing any animals other than a chance bull-bison which they shot for food. To the south of the Bow river they found an Indian camp pitched in a spot where the tender grass afforded rich pasture for the buffalo; but the plains, which were ordinarily black with moving herds, were at this time strangely deserted. After several moves, they finally struck a large encampment of Piegans near the present site of Calgary. Sending some of his men back to Manchester House, Thompson settled down in this camp to spend the winter.