204 Mackenzie’s Voyages the Nechaco followed in 1807. Receiving instructions to explore the ‘‘’Tacouche Tesse,” Fraser with Jules Maurice Quesnel, nineteen voyageurs, and two Indian guides, began the descent of the Great River, arriving at its mouth 2 July, 1808, after unspeakable difficulties. He found the position of the outlet to be in latitude 49° north, and realised that it was not the Columbia. David ‘Thompson, as previously stated, had crossed the Rockies in 1801-2—3. He was at first associated with the Hudson’s Bay Company as astronomer, but they intimated to him that exploring and surveying were not the services expected of him. He accordingly in 1797 transferred his allegiance to the North-West Company which welcomed him with open arms. He was instructed to determine the location of all its posts, to locate the forty-ninth parallel, to visit the Missouri, to inquire for fossils of large animals, and to search for archzological remains, and to enable him to prosecute these various activities he received an order on all the posts for what men, canoes, horses and supplies he might require. Leaving Rocky Mountain House 10 May, 1807, Thompson crossed over the divide to the Columbia which he reached 30 June. Paddling upstream to Windermere Lake, he built Fort Kootenay and wintered there. In June of the following year, while he was descending the Columbia from Kootenay Lake on his return journey to Rocky Mountain House, another North-Wester, Simon Fraser, on the fourteenth of the same month, had reached the junction of the Fraser and the Thompson in his perilous descent to the sea, so that the two were separated by about two hundred miles, both engaged in exploring new territory. Fraser heard from the Indians of the presence of Thomp- son’s party to the eastward.