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Europe and Asia, but are principally found in North America.
The general length of the animal is from two to three feet. The upper lip is cleft like that of the hare. The eyes are small, and far apart from each other. The fur is remarkably close and soft, but interspersed with long bristly hairs, which increase in quantity as the animal grows older. The legs seem short in proportion to the size of the body, especially the fore-legs but this generally is the case with all creatures whose habit it is to leap more than to walk, and to use the hind-legs for a support when in a standing position.
The tail of the beaver is the most peculiar part of its structure. It is very large, nearly half as long as the body, oval in shape, and flat, destitute of hair or fur, and marked into scaly divisions like the skin of a fish; it sometimes serves the animal as a prop when it stands erect, and uses its paws and teeth in working.
The history of the beaver, as related by Buffon and other writers, has been generally taken from the reports of the Indian hunters, whose accounts have been as contradictory as they have been exaggerated and wonderful, their object indeed not having been the study of the animal's mode of life and habits, but the seizure of his skin as a valuable article of commerce.
An authentic account of its ingenuity, skill, and perseverance, related by naturalists who have been eye-witnesses of this animal's sagacity, intelligence, and memory, will, we trust, be a subject not devoid of interest to our readers.
Beavers generally live in social companies, consisting of as many as two or three hundred individuals, and they inhabit extensive dwellings, which they build to the height of six or seven feet above the surface of the water. They select (if possible) a large pond, in which they raise their houses on piles, forming them either of a circular or oval shape, with arched tops; thus giving them on the outside the appearance of a dome, while within they somewhat resemble an oven. The number of houses is from ten to thirty. If the animals cannot find a pond to their liking, they fix on some flat piece of ground with a stream running through it, and in making this a suitable place for their habitations, they show a wonderful degree of instinct and sagacity.
Their first object is to stop the stream and to form a dam, and this they always do in the most favourable place for their purpose. They drive stakes five or six feet long into the ground, in different rows, and interweave them with branches of trees, filling up the interstices with clay, stones, and sand, which they ram down so firmly, that though the dams are frequently a hundred feet long, Captain Cartwright says he has walked over them with the greatest safety.
In various parts of the western country where beavers are now unknown, except by tradition, the dams constructed by their labours are still standing securely, and in many instances serve instead of bridges to the streams they cross. There are few states in the Union in which some remembrance of this animal is not preserved by such names as "Beaver-dam," "Beaver lake," "Beaver falls," &c.
The beaver dams are about ten or twelve feet thick at the base, and gradually diminish towards the top, which is seldom more than two or three feet across; towards the stream they are perpendicular, and sloped on the outside, where grass soon grows, and renders the earth more united. The materials used for their work are the trunks and branches of small birch, willow, poplar, and mulberry trees. The strength of their teeth and their perseverance in this work may be judged of by the size of the trees they cut down. Dr. Godman saw, while on the banks of the little Miami river, several stumps of trees of at least five or six inches in diameter, which had been evidently gnawed down by these animals. These trees are cut so as to fall into the water, and are then floated to the site of their dams or dwellings. Small shrubs they drag with their teeth to the stream. Many parts near their little colonies might be supposed to have had the aid of human industry in clearing.
Their work is always performed with much expedition and at night; they carry mud and stones, by holding them between their fore-paws and throat. The houses are constructed with the utmost ingenuity of earth, stones, and sticks, cemented together, and plastered on the inside with extraordinary neatness. As soon as any part of the material is placed where it is intended to remain, they turn round and give it a smart blow with their tail; a similar blow is struck by them upon the surface of the water when they are in the act of diving. The walls of their houses are about two feet thick, and the floors so much higher than the surface of the water, as to prevent them being flooded. Some of the houses have but one floor, others three. The number of beavers in each house is from two to ten. These sleep on the floor, which is strewed with leaves and moss, and each individual is said to have its own place. When they form a new settlement, they begin to build their dwellings in the summer, and it costs them a whole season to finish the work, and lay in their winter stock of provisions. These consist of bark and the tender branches of trees cut into certain lengths and piled in heaps under the water.