e who
knew thoroughly what he was about.

The size of a dam depends entirely upon the wishes of its builders and
location and general conditions of land and water. Sometimes the more
ambitious beavers build a dam a quarter of a mile in length. They employ
exactly the same principle as is used in making a mill-dam. Beavers,
however, were building dams long before millers came into existence, and
their methods are fully as scientific as those of man. Mill-dams usually
run straight across a stream, while beaver-dams are so curved that the
water is gently turned to each side. In this way the beaver-dams are
capable of resisting immense quantities of water which in its impetuous
rush would carry away the ordinary mill-dam. Many scientific thinkers
claim that the beaver employs this principle of construction without
knowing it. How absurd! Who can be sure that he doesn't know it?
Scientists of the old school desire proof before they will accept
anything as a fact, yet they themselves repeatedly make wild statements
without proper substantiation.

It is not unusual for a beaver family to select a home on the bank of a
pond, lake, or stream whose waters are sufficiently deep and abundant
for all their needs. In such a case dams are not needed, and regulation
beaver houses are rarely constructed. Instead, apartment houses are
hollowed out from the banks. But in the ease of a town-site on shallow,
narrow waters, dams are absolutely necessary to insure sufficient depth
to conceal the beavers, and to prevent obstruction by ice. The entrance
to the beaver's home is almost always under the water. This arrangement
safeguards the home from predatory enemies.

During the summer months, beavers are inclined to live alone, except
when a new home occupies their attention; but when autumn comes, the
various families of a neighbourhood meet and remain together through the
following spring. In the latter part of August the busy season begins,
and each and every beaver, old and young, aids in repairing the dam and
dwellings, which have been allowed to fall into decay. The cutting and
felling of trees is the first important work to be done.

These interesting "tree-cutters" usually work in pairs, and are
sometimes assisted by younger beavers; thus the family works together in
cutting and felling the trees, but in other forms of labour it seems
that several families work together. If only two are engaged in felling
a tree, they work by turns