We have stated that Peter Pond had prepared a map of the north country, with the purpose of presenting it to the Empress of Russia. Being a man of great energy, he was not deterred from this undertaking by the fact that he had no knowledge of astronomical instruments and little of the art of map-making. His statements were made on the basis of reports from the Indians, whose custom was always to make the leagues short, that they might boast of the length of their journeys. Computing in this way, he made Lake Athabasca so far from Hudson Bay and the Grand Portage that, taking Captain Cook's observations on the Pacific Coast four years before this, the lake was only, according to his calculations, a hundred or a hundred and fifty miles from the Pacific Ocean. The effect of Pond's calculations, which became known in the Treaty of Paris, was to stimulate the Hudson's Bay Company to follow up Hearne's discoveries and to explore the country west of Lake Athabasca. They attempted this in 1785, but they sent out a boy of fifteen, named George Charles, who had been one year at a mathematical school, and had never made there more than simple observations. As was to have been expected, the boy proved incompetent. Urged on by the Colonial Office, they again in 1791 organized an expedition to send Astronomer Philip Turnor to make the western journey. Unaccustomed to the Far West, and poorly provided for this journey, Turner found himself at Fort Chipewyan entirely dependent for help and shelter on the Nor'-Westers. He was, however, qualified for his work, and made correct observations, which settled the question of the distance of the Pacific Ocean. Mr. Roderick McKenzie showed him every hospitality. This expedition served at least to show that the Pacific was certainly five times the distance from Lake Athabasca that Pond had estimated. [Illustration: SIR ALEXANDER MACKENZIE.] After coming back from the Arctic Sea, Alexander Mackenzie spent his time in urging forward the business of the fur trade, especially north of Lake Athabasca; but there was burning in his breast the desire to be the discoverer of the Western Sea. The voyage of Turner made him still more desirous of going to the West. Like Hearne, Alexander Mackenzie had found the want of astronomical knowledge and the lack of suitable instruments a great drawback in determining his whereabouts from day to day. With remarkable energy, he, in the year 1791, journeyed eastward to Canada, crossed the Atlantic Ocean to London, and spent the winter in acquiring the requisite mathematical knowledge and a sufficient acquaintance with instruments to enable him to take observations. He was now prepared to make his journey to the Pacific Ocean. He states that the courage of his party had been kept up on their reaching the Arctic Sea, by the thought that they were approaching the Mer de l'Ouest, which, it will be remembered, Verendrye had sought with such passionate desire.