r always
tranquil would be left in quite distant beds.... Every dry part of
the earth's surface, when the presence or the abundance of marine
fossils prove that formerly the sea has remained in that place, has
necessarily twice received, for a single incursion of the sea,
littoral shells, and once deep-sea shells, in three different
deposits--this will not be disputed. But as such an incursion of the
sea can only be accomplished by a period of immense duration, it
follows that the littoral shells deposited at the first sojourn of
the edge of the sea, and constituting the first deposit, have been
destroyed--that is to say, have not been preserved to the present
time; while the deep-water shells form the second deposit, and there
the littoral shells of the third deposit are, in fact, the only ones
which now exist, and which constitute the fossils that we see."

He again asserts that these deposits could not be the result of any
sudden catastrophe, because of the necessarily long sojourn of the sea
to account for the extensive beds of fossil shells, the remains of
"infinitely multiplied generations of shelled animals which have lived
in this place, and have there successively deposited their debris." He
therefore supposes that these remains, "continually heaped up, have
formed these shell banks, become fossilized after the lapse of
considerable time, and in which it is often possible to distinguish
different beds." He then continues his line of anti-catastrophic
reasoning, and we must remember that in his time facts in biology and
geology were feebly grasped, and scientific reasoning or induction was
in its infancy.

"I would again inquire how, in the supposition of a universal
catastrophe, there could have been preserved an infinity of delicate
shells which the least shock would break, but of which we now find a
great number uninjured among other fossils. How also could it happen
that bivalve shells, with which calcareous rocks and even those
changed into a silicious condition are interlarded, should be all
still provided with their two valves, as I have stated, if the
animals of these shells had not lived in these places?

"There is no doubt but that the remains of so many molluscs, that so
many shells deposited and consequently changed into fossils, and
most of which were totally destroyed before their substance became
silicified, furnished a great part of the calcare