Commonly a house is built in the pond or on the edge of it. But on a little space of raised ground, within ten feet of the lower end of the canal and the edge of the pond, the foundation for a house was being excavated. Two tunnels were made through it to the bottom of the pond. The house was made of mud dredged from the bottom of the pond, and this was reënforced with an entire clump of willows cut near by. There were also used willow roots, sods, a few stones, and a few peeled aspen sticks off which the beavers had eaten the bark, and which they dragged from their temporary home--the old house. The finished house was about ten feet across the bottom and five feet high. The walls were about two feet thick. The ventilation top was a mass of criss-crossed sticks without mud. Beavers do most of their work at night--this probably is for safety from men. It appears that at one time they may have regularly worked during the daytime. But for generations hunters with guns have made day work perilous. In out-of-the-way places where they had not been disturbed I have seen a whole colony at work during the daytime even when the work was not pressing. With exceptions they now work daytime only in emergencies. At this place no one was troubling the beavers and frequently I saw an old one, and at length I realized that it had been the same old one each time. I was sitting on the side of the beaver house one afternoon changing a roll of films when the old beaver rose on the pond and swam to a half-submerged log about twenty feet away. I stopped film changing and sat still to watch him. He had not scented me. Splendid reflections he and the surroundings made in the water; the snowy top of Mount Meeker, the blue sky, white clouds, brown willows, green, pointed pines, red birches, and a single young aspen with yellow leaves--a brilliant autochrome of autumn. The beaver rose from squatting and scratched himself behind a fore leg, combed himself with forepaws, then standing high on his hind feet held forepaws close to his breast and looked around. A fly alighted on his nose. He struck at it. Again it alighted, and he brushed it away with the other forepaw. Again he squatted on the log but facing in the opposite direction. A few minutes later he dived off showing his wide, webbed, gooselike hind feet, and striking the water a heavy, merry whack with his broad black rubbery tail, sending the ripples scurrying over the pond. The canal still remained empty, but with the completion of the house it would be filled from somewhere and used in bringing in the harvest. One day late in September I found the canal and the little basin at the south--the upper--end full of water. A spring concealed among the willows forty feet above had been used. From the spring a small ditch had been dug by the beavers and through this the water was pouring rapidly into the now overflowing canal. [Illustration: _Photo. by S. N. Leek_ _Mountain Lion_]