new how to rule it. This done, they rested in no great
anxiety, expecting the thaw to end with a stringent frost.

Then, however, came the second, and more significant, manifestation of
peril. The snow on the ice-roof had vanished; and looking up through the
ice they saw the flood eddying riotously over the naked expanse. It was
a portent which the wiser elders understood. The whole colony fell to
work strengthening the dam where the weight of the current bore down
upon it, and increasing the outlet along the farther edges.

A thaw so persistent, however, and at the same time so violent,
overpassed their cunning calculations. One night, when all had done
their best and, weary, but reassured, had withdrawn into the warm
chamber of the lodge, something happened that they had never looked for.
In their snug retreat they were falling to sleep, the rush of the
overflow and the high clamour of the side vents coming dimly to their
ears, when suddenly they were startled by the water being forced up over
the dry floor of the chamber. The pressure of water beneath the ice had
suddenly increased. They were more than startled. They were badly
frightened. If the water should rise much higher they would be drowned
helplessly, for the ice lay close all over the pond. The younger ones
scurried this way and that with plaintive squeaks, and several dashed
forth into the pond in a panic, forgetting that there was no escape in
that direction. A moment later a low crashing penetrated to the dark
chamber; and the invading water retreated down the tunnel. The ice-roof,
worn thin, honey-combed, and upheaved by the pressure from below, had
gone to pieces.

It was the older and wiser beavers who had remained in the chamber,
terrified, but not panic-stricken. When the water retreated to its
normal level,--about two inches below the chamber floor,--they were
satisfied. Then, however, a louder and heavier note in the rush of the
overflow came to their ears, and their anxiety returned with fresh
force. Thrusting their whiskered noses inquiringly down the tunnel, they
observed that the water was sinking far below its proper level. Well
they knew what that meant. The dam was broken. The water, which was
their one protection from the terrors of the forest, was escaping.

This was the kind of an emergency which a beaver will always rise to.
Shy as they are, under ordinary circumstances, when the dam is attacked
their courage is unfailing. In a moment