From this band to the North Sea, on the east, and the Channel, on the
South, the chalk is largely hidden by other deposits; but, except in the
Weald [60] of Kent and Sussex, it enters into the very foundation of all
the south-eastern counties.
Attaining, as it does in some places, a thickness of more than a
thousand feet, the English chalk must be admitted to be a mass of
considerable magnitude. Nevertheless, it covers but an insignificant
portion of the whole area occupied by the chalk formation of the globe,
which has precisely the same general characters as ours, and is found
in detached patches, some less, and others more extensive, than the
English.
Chalk occurs in north-west Ireland; it stretches over a large part of
France,--the chalk which underlies Paris being, in fact, a continuation
of that of the London basin; it runs through Denmark and Central Europe,
and extends southward to North Africa; while eastward, it appears in the
Crimea and in Syria, and may be traced as far as the shores of the Sea
of Aral, in Central Asia.
If all the points at which true chalk occurs were circumscribed, they
would lie within an irregular oval about three thousand miles in long
diameter--the area of which would be as great as that of Europe, and
would many times exceed that of the largest existing inland sea--the
Mediterranean.
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