nd an outlet
on the shore.
The western slope of the great Scotch range is no less remarkable for
its glacier-traces. The heads of Loch Long, Loch Fyne, Loch Awe, and
Loch Leven everywhere show upon their margins the most distinct glacial
polish and furrows, while from the trend of these marks and the
distribution of the moraines, especially about Ben Cruachan, it is
obvious that in this part of the country the glaciers moved westward and
southward. About Aberdeen, on the contrary, they moved eastward, while
in the vicinity of Elgin they advanced toward the north.
It thus appears that the whole range of the Grampians formed a great
centre for the distribution of glaciers, and that a colossal ice-field
spread itself over the whole country, extending in every direction
toward the lower lands and the sea-shore. As the glaciers which now
descend through all the valleys of the Alps, along their northern as
well as their southern slopes, and in their eastern as well as their
western prolongation, though limited, in our days, within the
valley-walls, nevertheless once covered the plain of Switzerland and
that of Northern Italy, so did the ice-fields of the Grampians during
the greatest extension of the Scotch glaciers spread over the whole
country. They also were, in course of time, reduced to local glaciers,
circumscribed within the higher valleys of the more mountainous parts of
the country, until they totally disappeared, as those of Switzerland
would also have done, had it not been for the greater elevation of that
country above the level of the sea. Scotland nowhere rises above the
present level of perpetual snow, while in Switzerland the whole Alpine
range has an altitude favorable to the preservation of glaciers. In the
range of the Jura, however, which had at one time its local glaciers
also, but which nowhere now rises above the line of perpetual snow, they
have disappeared as completely as in the Grampian Hills.
It would lead me too far, were I to give here a special account of all
the investigations I made in 1840 upon the distribution of glaciers in
Great Britain. I will therefore only point out a few of the more
distinct areas of distribution. The region surrounding Ben Wyvis formed
such a centre of dispersion from which glaciers radiated, and we have
another in the Pentland Hills about Edinburgh. In Northumberland, the
Cheviot Hills present a glacial centre of the same kind, and in the
Westmoreland Hills we
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