The journey was carefully prepared for. With the characteristic shrewdness of the North-West Company, it was so planned as to require little expenditure. Thompson was to be accompanied chiefly by free-traders, i.e. by men to whom certain quantities of goods would be advanced by the Company. By the profits of this trade expenses would be met. The guide and interpreter was René Jussaume (a man of very doubtful character), who had fallen into the ways of the Western Indians. He had lived for years among the Mandans, and spoke their language. Another free-trader, Hugh McCracken, an Irishman, also knew the Mandan country, while several French Canadians, with Brossman, the astronomer's servant man, made up the company. Each of the traders took a credit from Mr. McDonnell of from forty to fifty skins in goods. Ammunition, tobacco, and trinkets, to pay expenses, were provided, and Thompson was supplied with two horses, and his chief trader, Jussaume, with one. The men had their own dogs to the number of thirty, and these drew goods on small sleds. Crossing the Assiniboine, the party started south-westward, and continued their journey for thirty-three days, with the thermometer almost always below zero and reaching at times 36 deg. below. The journey was a most dangerous and trying one and covered 280 miles. Thompson found that some Hudson's Bay traders had already made flying visits to the Mandans. On his return, Thompson's itinerary was, from the Missouri till he reached the angle of the Souris River, seventy miles, where he found abundant wood and shelter, and then to the south end of Turtle Mountain, fourteen miles. Leaving Turtle Mountain, his next station was twenty-four miles distant at a point on the Souris where an outpost of Assiniboine House, known as Ash House, had been established. Another journey of forty-five miles brought the expedition back to the hospitable shelter of Mr. McDonnell at Stone Indian House. Thompson now calculated the position of this comfortable fort and found it to be 49 deg. 41´ (nearly) N. latitude and 101 deg. 1´ 4´´ (nearly) W. longitude.