内容简介：Towards the end of this story the readers of it will find an account of an "unknown lake" in the northern Rockies, together with a picture of its broad expanse, its glorious mountains, and of a white explorers' tent pitched beside it. She leant over the side of the observation platform, attached to the private car in which she and her brother were travelling, at the rear of the heavy Canadian Pacific train. To the left of the train a small blue lake had come into view, a lake much indented with small bays running up among the woods, and a couple of islands covered with scrub of beech and spruce, set sharply on the clear water.