overing
gently-rising lands; and the breadth of continuous lake-surface
seems to be in process of diminution, in the following way. A
bank of sand is first drifted up, in the line of a chain of
rocks which may happen to lie across the mouth of an inlet or
deep bay. Carices, balsam-poplars, and willows, speedily take
root therein; and the basin which lies behind, cut off from the
parent lake, is gradually converted into a marsh by the
luxuriant growth of aquatic plants. The sweet gale next appears
on its borders, and drift-wood, much of it rotten and
comminuted, is thrown up on the exterior bank, together with
some roots and stems of larger trees. The first spring storm
covers these with sand, and in a few weeks the vigorous
vegetation of a short but active summer binds the whole
together by a network of the roots of bents and willows.
Quantities of drift-sand pass before the high winds into the
swamp behind, and, weighing down the flags and willow branches,
prepare a fit soil for succeeding crops. During the winter of
this climate, all remains fixed as the summer left it; and as
the next season is far advanced before the bank thaws, little
of it washes back into the water, but on the contrary, every
gale blowing from the lake brings a fresh supply of sand from
the shoals which are continually forming along the shore. The
floods raised by melting snows cut narrow channels through the
frozen beach, by which the ponds behind are drained of their
superfluous waters. As the soil gradually acquires depth, the
balsam-poplars and aspens overpower the willows; which,
however, continue to form a line of demarcation between the
lake and the encroaching forest. Considerable sheets of water,
are also cut off on the northwest side of the lake, where the
bird's-eye limestone forms the whole of the coast. Very
recently this corner was deeply indented by narrow branching
bays, whose outer points were limestone cliffs. Under the
action of frost, the thin horizontal beds of this stone split
up, crevices are formed perpendicularly, large blocks are
detached, and the cliff is rapidly overthrown, soon becoming
masked by its own ruins. In a season or two the slabs break
into small fragments, which are tossed up by the waves across
the neck of the bay into
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