midday
It was the month of August , near its end , when they reached the Great Slave Lake , in the latitude of 62 degrees . The days had now become very short , and their journeys grew short in proportion . They already experienced weather as cold as an English winter . There were slight frosts at night -- though not yet enough to cover the water with ice -- and the midday hours were hot , sometimes too hot to be comfortable . But this only caused them to feel the cold the more sensibly when evening set in ; and all their robes and skins were necessary to keep them warm during the night . The Great Slave Lake , like the Athabasca , is very long and very narrow . It extends full 260 miles from east to west , but at its widest part is not over thirty , and in some places much less .