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Young Folks' Library: Wonders of Earth, Sea and Sky

On A Piece Of Chalk
A LECTURE TO WORKING MEN.
(Delivered in England.)
By
T.H. HUXLEY.
If a well were to be sunk at our feet in the midst of the city of Norwich, the diggers would
very soon find themselves at work in that white substance almost too soft to be called
rock, with which we are all familiar as "chalk."
Not only here, but over the whole county of Norfolk, the well-sinker might carry his shaft
down many hundred feet without coming to the end of the chalk; and, on the sea-coast,
where the waves have pared away the face of the land which breasts them, the scarped
faces of the high cliffs are often wholly formed of the same material. Northward, the
chalk may be followed as far as Yorkshire; on the [pg 172] south coast it appears abruptly in the
picturesque western bays of Dorset, and breaks into the Needles of the Isle of Wight;
while on the shores of Kent it supplies that long line of white cliffs to which England
owes her name of Albion.
Were the thin soil which covers it all washed away, a curved band of white chalk, here
broader, and there narrower, might be followed diagonally across England from Lulworth
in Dorset, to Flamborough Head in Yorkshire—a distance of over two hundred and
eighty miles as the crow flies.
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 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 character 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.
[pg 173]
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.
Thus the chalk is no unimportant element in the masonry of the earth's crust, and it
impresses a peculiar stamp, varying with the conditions to which it is exposed, on the
scenery of the districts in which it occurs. The undulating downs and rounded coombs,
covered with sweet-grassed turf, of our inland chalk country, have a peacefully domestic
 
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