t was night or day in the
wide, frozen, perilous world above the ice-roof, whether the sun shone
from the bitter blue, or the wolf-haunted moonlight lay upon the snow,
or the madness of the blizzard made the woods cower before its fury.

[Illustration: "WOULD WHISK SHARPLY INTO THE MOUTH OF THE BLACK
TUNNEL."]

As long as the cold endured and the snow lay deep upon the wilderness,
the beavers lived their happy, uneventful life beneath the ice-roof. But
in this particular winter the untempered cold of December and January,
which slew many of the wood folk and drove the others wild with hunger,
broke suddenly in an unprecedented thaw. Not the oldest bear of the Bald
Mountain caves could remember any such thaw. First there were days on
days, and nights on nights, of bland, melting rain, softer than April's.
The snow vanished swiftly from the laden branches of fir and spruce and
hemlock, and the silent woods stood up black and terrible against the
weeping sky. On the ground and on the ice of pond and stream the snow
shrank, settled, and assumed a grayish complexion. Water, presently,
gathered in great spreading, leaden-coloured pools on the ice; and on
the naked knolls the bare moss and petty shrubs began to emerge. Every
narrow watercourse soon carried two streams,--the temperate, fettered,
summer-mindful stream below the ice, and the swollen, turbulent flood
above. Then the rain stopped. The sun came out warm and urgent as in
latter May. And snow and ice together dwindled under the unnatural
caress.

The beavers, in their safe seclusion, had knowledge in two ways of this
strange visitation upon the world. Not all the soft flood of the melting
snow ran over the surface of their ice, but a portion got beneath it, by
way of the upper brooks. This extra flow disturbed both the colour and
the temperature of the clear amber water of the pond. It lifted heavily
against the ice, pressed up the tunnels to the very edge of the dry
chamber of the lodge, and thrust ponderously at the outlets of the dam.
Understanding the peril, the wise little dam-builders sallied forth in a
flurry, and with skilful tooth and claw lost no time in enlarging the
outlets. They were much too intelligent to let the flood escape by a
single outlet, lest the concentrated flow should become too heavy for
them to control it. They knew the spirit of that ancient maxim of
tyrants, "_divide et impera_." By dividing the overflow into many feeble
streams they k