correcting their early mistakes by fresh facts, till they have
at last got hold of the true key to the mystery, and are as certain
of the existence of the great island of the Weald, and its gradual
destruction by the waves and currents of an ancient sea, as if they
had seen it with their bodily eyes. 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. It was found that the floor of the Atlantic Ocean, after you
have left the land a few hundred miles, is one vast plain of mud, of
some thirteen hundred miles in breadth. But here is the wonder; it
was found that at a depth, averaging 1,600 fathoms--9,600 feet--in
utter darkness, the sea floor is covered with countless millions of
animalcule-shells, of the same families, though not of the same
species, as those which compose the chalk.

At the bottom of a still ocean, then, the chalk was deposited. But
it took many an age to raise it to where Odiham chalk-pit now
stands.

But how was it raised?

By the upheaving force of earthquakes. Or rather, by the upheaving
force which causes earthquakes, when it acts in a single shock,
cracking the earth's crust by an explosion; but which acts, too,
slowly