BEAVER " LODGES." 55 



zontally, and loading them witli stones and eartli until tliey 

 can resist the pressure of the water. A considerable 

 quantity are thus used ; and as fast as the water rises, 

 fresh materials are added, being obtained chiefly from the 

 trunks and branches of trees which have been already 

 stripped of their bark. 



In places where the stream runs with a slow current, 

 the dam is carried right across the river ; but when the 

 waters flow rapidly, a convex shape is given to it, that it 

 may more easily resist their force. Frequently the dam is 

 very large, measuring six to eight hundred feet in length, 

 and ten to 'twelve feet in thickness. In the wooded 

 districts of America, broad swamps have been formed 

 by the diverted waters of streams dammed up by the 

 beavers. 



It is in this way that the beavers keep up the water to 

 the required level : we must now see what use they make 

 of the reservoirs thus formed. They excavate their 

 burrows close to the brink, and communicate with the 

 water by means of underground galleries ; one entrance of 

 which opens into the house or " lodge," as it is popularly 

 called, and the other at a suflticient distance below the 

 surface of the stream to prevent it from being closed by 

 the ice. Hence the beaver can always gain access to his 

 stores, and return to his " lodge," without exposing himself 

 to view. 



The " lodge" is nearly circular in form, and bears a close 

 resemblance to the dome-shaped snow-huts of the Esqui- 

 maux. The average height is three feet, and the diameter 

 six to seven feet; the outline is that of an irregular 



