THE BEAVER. 13 
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 com- 
pletely 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 some- 
thing 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 
settled this question, it goes to the opposite side of the 
tree, and with two or three powerful bites cuts away the 
wood, so that the tree becomes overbalanced and falls to 
the ground. 
This point having been reached, the animal proceeds 
to cut up the fallen trunk into lengths, usually a yard or 
so in length, employing a similar method of severing the 
wood, In consequence of this mode of gnawing the timber, 
both ends of the logs are rounded and rather pointed, as 
may be seen by reference to the frontispiece. In the 
Zoological Gardens may be seen many excellent examples 
of timber which has been cut by the Beaver: the logs 
and cut stumps which are given in the frontispiece were 
sketched from those objects. 
The next part of the task is, to make these logs intu 
a dam. Now, whereas some persons have endeavoured 
to make the Beaver a more ingenious animal than it 
really is, and have accredited it with powers which only 
belong to mankind, others have gone to the other ex- 
treme, and have denied the existence of a regularly built 
dam, saying that it is entirely accidental, and caused by 
