Their fate, again, is what was to be expected if the glacier ends, as
it commonly does in Arctic regions, in the sea. The ice grows out to
sea-ward for more than a mile sometimes, about one-eighth of it being
above water, and seven-eighths below, so that an ice-cliff one
hundred feet high may project into water eight hundred feet deep. At
last, when it gets out of its depth, the buoyancy of the water breaks
it off in icebergs, which float away, at the mercy of tides and
currents, often grounding again in shallower water, and ploughing the
sea-bottom as they drag along it. These bergs carry stones and dirt,
often in large quantities; so that, whenever a berg melts or
capsizes, it strews its burden confusedly about the sea-floor.
Meanwhile the fine mud which is flowing out from under the ice goes
out to sea likewise, colouring the water far out, and then subsiding
as a soft tenacious ooze, in which the stones brought out by the ice
are imbedded. And this ooze--so those who have examined it assert--
cannot be distinguished from the brick-clay, or fossiliferous
boulder-clay, so common in the North. A very illustrious
Scandinavian explorer, visiting Edinburgh, declared, as soon as he
saw the sections of boulder-clay exhibited near that city, that this
was the very substance which he saw forming in the Spitzbergen ice-
fiords.
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