t have solidity and hardness
to resist the sudden changes which its moving fluids would occasion, it
must be made subject to decay and, waste upon the surface exposed to the
atmosphere; for, such an earth as were made incapable of change, or not
subject to decay, could not afford that fertile soil which is required
in the system of this world, a soil on which depends the growth of
plants and life of animals,--the end of its intention.

Now, we find this earth endued precisely with that degree of hardness
and consolidation, as qualifies it at the same time to be a fruitful
earth, and to maintain its station with all the permanency compatible
with the nature of things, which are not formed to remain unchangeable.

Thus we have a view of the most perfect wisdom, in the contrivance of
that constitution by which the earth is made to answer, in the best
manner possible, the purpose of its intention, that is, to maintain and
perpetuate a system of vegetation, or the various race of useful plants,
and a system of living animals, which are in their turn subservient to a
system still infinitely more important, I mean, a system of intellect.
Without fertility in the earth, many races of plants and animals would
soon perish, or be extinct; and, without permanency in our land, it were
impossible for the various tribes of plants and animals to be dispersed
over all the surface of a changing earth. The fact is, that fertility,
adequate to the various ends in view, is found in all the quarters of
the world, or in every country of the earth; and, the permanency of our
land is such, as to make it appear unalterable to mankind in general,
and even to impose upon men of science, who have endeavoured to persuade
us that this earth is not to change. Nothing but supreme power and
wisdom could have reconciled those two opposite ends of intention, so as
both to be equally pursued in the system of nature, and both so equally
attained as to be imperceptible to common observation, and at the same
time a proper object for the human understanding.

We thus are led to inquire into the efficient causes of this
constitution of things, by which solidity and stability had been
bestowed upon a mass of loose materials, and by which this solid
earth, formed first at the bottom of the sea, had been placed in the
atmosphere, where plants and animals find the necessary conditions of
their life.

Now, we have shown, that subterraneous fire and heat had been