1911 Encyclopædia Britannica/Great Slave Lake
GREAT SLAVE LAKE (Athapuscow), a lake of Mackenzie district, Canada. It is situated between 60º 50' and 62º 55' N. and 108º 40' and 117º W., at an altitude of 391 ft. above the sea. It is 325 m. long, from 15 to 50 m. wide, and includes an area of 9770 sq. m. The water is very clear and deep. Its coast line is irregular and deeply indented by large bays, and its north-eastern shores are rugged and mountainous. The western shores are well wooded, chiefly with spruce, but the northern and eastern are dreary and barren. It is navigable from about the 1st of July to the end of October. The Yellow-knife, Hoar-frost, Lockhart (discharging the waters of Aylmer, Clinton-Colden and Artillery Lakes), Tchzudezeth, Du Rocher, Hay (400 m. in length), and Slave rivers empty into Great Slave Lake. The bulk of its water empties by the Mackenzie river into the Arctic Ocean, but a small portion finds its way by the Ark-i-linik river into Hudson's Bay. It was discovered in 1771 by Samuel Hearne.