How Animals Work. 



which at the approach of autumn are well filled with 

 a supply of winter fodder. Outside, the whole fabric 

 measures from twelve to twenty feet in diameter and 

 some six or eight feet in height. In front of the 

 lodge, according to Audubon, the Beavers scratch away 

 the mud of the bottom of the stream until they make 

 the water of sufficient depth to enable them to float 

 their pieces of timber to this point, even when the 

 water is frozen ; and communicating with this a ditch 

 surrounds the lodge, which is also made so deep that 

 it will not readily freeze to the bottom. It is into this 

 ditch or moat, and the deep water in front of the lodge, 

 that the passages from the living chamber always open, 

 and thus the Beavers can at any time make their way 

 out unobserved. 



For the building of the lodge, and for food, the 

 Beavers cut down the trees on the edge of the stream 

 by the aid of their strong chisel-like teeth. This is 

 accomplished by gnawing all round the trunk for a 

 certain distance, and gradually working deeper and 

 deeper into the substance of the tree in such a manner 

 that just before its fall the tree stands upon quite a 

 slender waist of wood, with the trunk both above and 

 below this tapered off into the form of two cones whose 

 points are united by the waist. The Beavers work in 

 such a way as to weaken the side nearest to the water, 

 so that when the tree falls it descends in that direction. 

 The tree felled, its trunk and branches are cut up into 

 lengths of from five to six feet, which, after the bark 

 has been stripped off and eaten, are employed in the 

 construction of the lodge, or the formation of the dam 

 which may be thrown across the stream to keep the 



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