2 4-6 
STRANGE DWELLINGS. 
mark, or, at all events, to prevent it from sinking below the ( 
requisite level. 
If any modern engineer were asked how to attain such an 
object, he would probably point to the nearest water-mill, and 
say that the problem had there been satisfactorily solved, a dam 
having been built across the stream so as to raise the water to 
the requisite height, and to allow the superfluous water to flow 
away. Now, water is as needful for the Beaver as for the miller, 
and it is a very curious fact, that long before millers ever in- 
vented dams, or before men ever learned to grind corn, the 
Beaver knew how to make a dam and insure itself a constant 
supply of w r ater. 
That the Beaver does make a dam is a fact that has long been 
familiar, but how it sets to work is not so well known. Engrav- 
ings representing the Beavers and their habitations, are common 
enough, but they are generally untrustworthy, not having been 
drawn from the natural object, but from the imagination of the 
artist. In most cases the dam is represented as if it had been 
made after the fashion of our time and country, a number of 
stakes having been driven into the bed of the river, and smaller 
branches entwined among them. The projecting ends of the 
stakes are neatly squared off, and altogether the work looks 
exactly as if it had been executed by human hands. One artist 
seems to have copied from another, so that the error of one man 
has been widely perpetuated by a series of successors. 
Now, in reality, the dam is made in a very different manner, 
and in order to comprehend the mode of its structure, we must 
watch the Beaver at work. 
When the animal has fixed upon a tree which it believes to be 
suitable for its purpose, it begins by sitting upright, and with its 
chisel-like teeth, cutting a bold groove completely round the 
trunk. It then widens the groove, and always makes it wide in 
exact proportion to its depth, so that when the tree is nearly cut 
through, it looks something like the contracted portion of an 
hour-glass. When this stage has been reached, the Beaver looks 
anxiously at the tree, and views it on every side, as if desirous 
of measuring the direction in which it is to fall. Having 
