204 
THE BEAVER. 
of his Natural History, is calculated to correct 
many of those misapprehensions which formei’l)' 
prevailed respecting the beaver. From tha* 
source the following particulars are derived. 
In a state of nature, the instincts of 
beavers are exerted for two principal objects! 
to secure such a depth of water that it cann^^ 
be frozen to the bottom ; and to construe* 
huts for their winter habitations. 
If the beavers choose for their residence 
spot where the water is not of sufficient depth' 
they set about obviating the inconvenience b/ 
building a dam. The materials used in th^ 
construction of dams are the trunks 
branches of small birch, w'illow, poplar, mwb 
bony, and other trees. They begin to 
down their timber for building early in tb^ 
summer, but they do not begin building tb^ 
the middle or end of August, and their edifice^ 
are not finished until the beginning of the cob^ 
season. The strength of their teeth, and theb 
