the question we are considering just now. We are now
inquiring into the origin of those huge boulders that are found upon our
coasts and on the coasts of other lands--boulders which could not have
rolled down from the hills, for there are no hills at all near many of
them; and those hills that are near some of them are of different
geological formation.
This question will be answered at once, and one of the phenomena of
arctic ice and oceanic agency will be exhibited, by reference to the
recent discoveries of the celebrated arctic voyager, Dr Kane of the
American Navy.
While wintering far beyond the head of Baffin's Bay, and beyond the most
northerly point, in that direction, that had at that time been reached
by any previous traveller, Dr Kane made many interesting observations
and discoveries. He seems to have penetrated deep into the heart of
Nature's northern secrets. Among other things, he ascertained the
manner in which boulders are transported from their northern home.
The slow, creeping movement of glaciers, to which we have already
referred, is one means whereby large boulders are formed. At the lower
edge of one of the glaciers of Norway we saw boulders, thirty or forty
feet in diameter, which had been rolled and forced, probably for ages,
down the valley by the glacier, and thrust out on the sea-beach, where
they lay with their angles and corners rubbed off and their surfaces
rounded and smoothed as completely as those of the pebbles by which they
were surrounded.
Had these boulders been formed in the arctic regions, they might have
been thrust out upon the thick solid crust of the frozen sea, which in
time would have been broken off and floated away; thus rafting the
boulders to other shores. The formation of boulders, and their
positions, are facts that we have seen. Their being carried out to sea
by ice-rafts is a fact that Dr Kane has seen and recorded. On the wild
rocky shores where his ship was set fast, there was a belt of ice lining
the margin of the sea, which he termed the "ice-belt," or the
"ice-foot." This belt never melted completely, and was usually fast to
the shore. In fact it was that portion of the sea-ice which was left
behind each spring when the general body of ice was broken up and swept
away. Referring to this, he writes:
"The spot at which we landed I have called Cape James Kent. It was a
lofty headland, and the land-ice which hugged its base was covered with
rock
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