conducts the work.

In taking this view of things, where ends and means are made the object
of attention, we may hope to find a principle upon which the comparative
importance of parts in the system of nature may be estimated, and also
a rule for selecting the object of our inquiries. Under this direction,
science may find a fit subject of investigation in every particular,
whether of _form_, _quality_, or _active power_, that presents itself in
this system of motion and of life; and which, without a proper
attention to this character of the system, might appear anomalous and
incomprehensible.

It is not only by seeing those general operations of the globe which
depend upon its peculiar construction as a machine, but also by
perceiving how far the particulars, in the construction of that machine,
depend upon the general operations of the globe, that we are enabled to
understand the constitution of this earth as a thing formed by design.
We shall thus also be led to acknowledge an order, not unworthy of
Divine wisdom, in a subject which, in another view, has appeared as the
work of chance, or as absolute disorder and confusion.

To acquire a general or comprehensive view of this mechanism of the
globe, by which it is adapted to the purpose of being a habitable world,
it is necessary to distinguish three different bodies which compose the
whole. These are, a solid body of earth, an aqueous body of sea, and an
elastic fluid of air.

It is the proper shape and disposition of these three bodies that form
this globe into a habitable world; and it is the manner in which these
constituent bodies are adjusted to each other, and the laws of action
by which they are maintained in their proper qualities and respective
departments, that form the Theory of the machine which we are now to
examine.

Let us begin with some general sketch of the particulars now mentioned.

_1st_, There is a central body in the globe. This body supports those
parts which come to be more immediately exposed to our view, or which
may be examined by our sense and observation. This first part is
commonly supposed to be solid and inert; but such a conclusion is only
mere conjecture; and we shall afterwards find occasion, perhaps, to form
another judgment in relation to this subject, after we have examined
strictly, upon scientific principles, what appears upon the surface, and
have formed conclusions concerning that which must have been transacted
in s