"The beaver dams differ in shape, according to the nature of the place in which they are built. If the water in the river or creek have but little motion, the dam is almost straight; but, when the current is more rapid, it is always made with a considerable curve, convex toward the stream. The materials made use of are drift-wood, green willows, birch, and poplars, if they can be got; also mud and stones, intermixed in such a manner as must evidently contribute to the strength of the dam. In places which have been long frequented by beavers undisturbed, their dams, by frequent repairing, become a solid bank, capable of resisting a great force both of water and ice; and as the willow, poplar, and birch generally take root, and shoot up, they, by degrees, form a kind of regular planted hedge, in some places so tall that birds build their nests among the branches. The beaver-houses are constructed of the same materials as their dams, and are always proportioned in size to the number of inhabitants, which seldom exceeds four old and six or eight young ones. The houses are of a much ruder construction than their dams: for, notwithstanding the sagacity of these animals, it has never been observed that they aim at any other convenience in their house than to have a dry place to lie on; and there they usually eat their victuals, such as they take out of the water. Their food consists of roots of plants, like the pond-lily, which grows at the bottom of the lakes and rivers. They also eat the bark of trees, particularly those of the poplar, birch, and willow. "The instinct of the beavers leading them to live in associations, they are in an unnatural position, when, in any locality, their numbers are so much reduced as to prevent their following this instinct. The beaver near the settlement is sad and solitary: his works have been swept away, his association broken up, and he is reduced to the necessity of burrowing in the river-bank, instead of building a house for himself. Such beavers are called 'terriers.' One traveller says that these solitaries are also called 'old bachelors.'" THE WHITE, BROWN, OR GRISLY BEAR. "April 29.--All these names are given to the same species, which probably changes in color with the season, or with the time of life. Of the strength and ferocity of this animal, the Indians give dreadful accounts. They never attack him but in parties of six or eight persons, and, even then, are often defeated with the loss of some of the party.