You must take all this, of
course, as truth from me to-night; but you may go and examine for
yourselves; and see how far your own common sense and observations
agree with those of learned geologists.
The history of this great Wealden island to the south-east of us is
obscure enough; but a few general facts, which bear upon our gravel-
pit, I can give you.
I must begin, however, ages before the Wealden island existed; when
the chalk of which its mass was composed was at the bottom of a deep
ocean.
We know now what chalk is, and how it was made. We know that it was
deposited as white lime mud, at a vast sea-depth, seemingly
undisturbed by winds or currents. We know that not only the flint,
but the chalk itself, is made up of shells; the shell of little
microscopic animalcules smaller than a needle's point, in millions
of millions, some whole, some broken, some in powder, which lived,
and died, and decayed for ages in the great chalk sea.
We know this, I say. We had suspected it long ago, and become more
and more certain of it as the years went on. But now we seem to
have a proof of it which is past gainsaying.
In the late survey of the bottom of the Atlantic Ocean, with a view
to laying down the electric telegraph between England and America,
by Lieutenant Maury of the American navy, a great discovery was
made.
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