se, which is that of a world.

The general theory of this earth as a world, will thus appear to be a
complex thing, which however founded upon simple principles, contains
many subjects of discussion, and requires attention to a variety of
particulars. For, not only the great features of this earth are to be
explained by the theory, but also the most minute appearance, such as
are to be found, even with microscopic observation, in every particular
part.

Thus the nature, constitution, and cause of every particular appearance
in the construction of this earth, are to be investigated in a
geological theory, as well as that general constitution of the world in
which all the particular parts are to be employed for a purpose.

If the subject here examined shall be found properly explained, there
will remain little doubt with regard to the justness of the theory,
which will then be applicable to other appearances that may occur;
although every appearance is not to be explained, in a manner equally
satisfactory, by any theory which is not perfect.

The first subject to be examined is the modern theory of primitive
mountains. I have written several chapters upon that subject, having
successively acquired more light in this interesting part of the theory,
by observations of my own in several places of this country, as well as
from the natural history of other countries. I shall give these nearly
in the order in which they occurred, or had been written.

CHAP. IV.

The Supposition of Primitive Mountains refuted.

In the theory now given, the earth has been represented as a composition
of different materials, which had existed in another form, and as the
effect of natural operations; therefore, however various may be found
the structure of our earth, and however dissimilar some parts of
its composition may be in comparison with others, no part should be
considered as original, in relation to the globe, or as primitive, in
relation to second causes, _i.e._ physical operations by which those
parts should have been formed. But it is pretended by naturalists, that
there are certain primitive mountains in the earth, bodies which have
had another origin than that of the general strata of the globe and
subsequent masses; an origin, therefore, which cannot be considered as
having been produced from natural operations, or as effected in the
course of known causes. Now, if it can be made to appear, that there is
no solid ground f