Crossing the south-western extremity of the _Lake of the Hills_, they entered the _Slave river_, and steered, along that river, in a northerly direction. On the ensuing day they arrived at the foot of a succession of rapids; and, in the course of twelve miles, were obliged five times to unload the canoes, and carry the luggage considerable distances overland. One of the Indian canoes was borne, by the fury of the current, down the last of the cataracts, and was dashed to pieces. The hunters here killed seven geese, four ducks, and a beaver. The progress of the boats was much impeded by ice. The banks of the river, both above and below the rapids, were covered with wood. This was more particularly the case on the western side, where the land was low, and had a black and rich soil. The eastern banks were somewhat elevated; and the soil was a yellow clay, mixed with gravel. At a little distance from the banks were extensive plains, frequented by numerous herds of buffaloes; and the woods, adjacent to the river, were inhabited by elks and rein-deer. The habitations of beavers were seen in all the small lakes and rivers; and the swamps adjacent to the Slave-river, were sometimes covered with wild-fowl. In the morning of the 9th the voyagers arrived at the _Great Slave Lake_. Here they experienced a most uncomfortable change in the weather, which became extremely cold. The lake was still frozen; and they were obliged to delay their progress for several days, until they could effect a passage across it. In the mean while they occupied themselves in fishing and hunting, for the purpose of adding to their stock of provisions. They had more or less rain almost every day. On the 20th the ice had somewhat given way, and they recommenced their voyage, in a north-westerly direction. A few days after this, they landed on the main land, at three lodges of _Red-knife Indians_, so called from the copper knives which they use. M. le Roux purchased, of these Indians, some packs of beaver and marten-skins; and Mr. Mackenzie had several consultations with them concerning the country he was about to traverse; but he could obtain from them no information that was important to the objects of his expedition. He, however, engaged one of them, as a guide, in navigating the bays of the lake. The musquitoes were now so troublesome as to occasion the voyagers much inconvenience. After having, with considerable difficulty, navigated the northern side of the lake, they entered the mouth of a river, which lay in a westerly direction. On the 2d of July, they perceived, at a distance before them, a high mountain, or rather a cluster of mountains, which stretched southward, as far as the view could reach, and had their tops lost in the clouds. The declivities of these mountains were covered with wood; and they were sprinkled with glistening patches of snow, which, at first, Mr. Mackenzie mistook for white stones.