40 ROMANCE OF THE BEAVER 
length, while the height is in accordance with the 
demands of the stream. The more rapid the 
current the higher the dam. In very flat country, 
where the waterways are sluggish, and these are 
the most sought after by the beaver, they are 
usually not more than a foot or two in height. 
Few streams are too large, and none too small for 
dams. I have seen a stream less than two feet 
wide on which there were no less than seven 
within a distance of scarcely one hundred yards. 
Their chief object, apparently, was to keep the 
water from draining out of a flat alder swamp, 
from which the beavers were busily engaged in 
getting their winter supply of food. To have 
hauled branches through the tangled undergrowth 
would have been a difficult task, but by keeping 
the water only a few inches above its normal level 
they could make channels among the hummocks 
through which they could with comparative ease 
swim with the branches and sticks. 
In selecting the site for the dam, the beaver 
shows a remarkable power of discrimination, .and 
one wonders how it is that so short an animal can 
possibly make any survey of the country and get 
any appreciation of the conditions. They have 
two principal objects in view when selecting the 
site for a new house; an abundance of water, and 
trees whose bark is suitable for food. These are 
their needs, but the question of obtaining and 
controlling them requires serious consideration and 
