tions of clay form a large portion
of the present strata, all indurated and consolidated in various
degrees; but this great quantity of siliceous, argillaceous, and
other compound substances, in form of earth or impalpable sediment,
corresponds perfectly with that quantity of those same substances which
must have been prepared in the formation of so much gravel and sand, by
the attrition of those bodies in the moving waters.

Therefore, from the consideration of those materials which compose the
present land, we have reason to conclude, that, during the time this
land was forming, by the collection of its materials at the bottom of
the sea, there had been a former land containing materials similar to
those which we find at present in examining the earth. We may also
conclude, that there had been operations similar to those which we
now find natural to the globe, and necessarily exerted in the actual
formation of gravel, sand, and clay. But what we have now chiefly in
view to illustrate is this, that there had then been in the ocean a
system of animated beings, which propagated their species, and which
have thus continued their several races to this day.

In order to be convinced of that truth, we have but to examine the
strata of our earth, in which we find the remains of animals. In this
examination, we not only discover every genus of animal which at present
exists in the sea, but probably every species, and perhaps some species
with which at present we are not acquainted. There are, indeed,
varieties in those species, compared with the present animals which we
examine, but no greater varieties than may perhaps be found among the
same species in the different quarters of the globe. Therefore, the
system of animal life, which had been maintained in the ancient sea, had
not been different from that which now subsists, and of which it belongs
to naturalists to know the history.

It is the nature of animal life to be ultimately supported from matter
of vegetable production. Inflammable matter may be considered as the
_pabulum_ of life. This is prepared in the bodies of living plants,
particularly in their leaves exposed to the sun and light. This
inflammable matter, on the contrary, is consumed in animal bodies, where
it produces heat or light, or both. Therefore, however animal matter, or
the pabulum of life, may circulate through a series of digesting powers,
it is constantly impaired or diminishing in the course of t