when caribou-hunting was
wonderfully well placed. No engineer could have chosen better. It was
made by the same colony the lynx was after, and just below where he
went through his pantomime for my benefit; his tracks were there too.
The barrens of which I spoke are treeless plains in the northern
forest, the beds of ancient shallow lakes. The beavers found one with
a stream running through it; followed the stream down to the foot of
the barren, where two wooded points came out from either side and
almost met. Here was formerly the outlet; and here the beavers built
their dam, and so made the old lake over again. It must be a
wonderfully fine place in summer--two or three thousand acres of
playground, full of cranberries and luscious roots. In winter it is
too shallow to be of much use, save for a few acres about the beavers'
doorways.

There are three ways of dam-building in general use among the beavers.
The first is for use on sluggish, alder-fringed streams, where they
can build up from the bottom. Two or three sunken logs form the
foundation, which is from three to five feet broad. Sticks, driftwood,
and stout poles, which the beavers cut on the banks, are piled on this
and weighted with stones and mud. The stones are rolled in from the
bank or moved considerable distances under water. The mud is carried
in the beaver's paws, which he holds up against his chin so as to
carry a big handful without spilling. Beavers love such streams, with
their alder shade and sweet grasses and fringe of wild meadow, better
than all other places. And, by the way, most of the natural meadows
and half the ponds of New England were made by beavers. If you go to
the foot of any little meadow in the woods and dig at the lower end,
where the stream goes out, you will find, sometimes ten feet under the
surface, the remains of the first dam that formed the meadow when the
water flowed back and killed the trees.

The second kind of dam is for swift streams. Stout, ten-foot brush is
the chief material. The brush is floated down to the spot selected;
the tops are weighted down with stones, and the butts left free,
pointing down stream. Such dams must be built out from the sides, of
course. They are generally arched, the convex side being up stream so
as to make a stronger structure. When the arch closes in the middle,
the lower side of the dam is banked heavily with earth and stones.
That is shrewd policy on the beaver's part; for once the ar