al region is exposed to the day. The solid body being thus
gradually impaired, there are moving powers continually employed, by
which the summits of our land are constantly degraded, and the materials
of this decaying surface travelled towards the coast. There are other
powers which act upon the shore, by which the coast is necessarily
impaired, and our land subjected to the perpetual incroachment of the
ocean.

Here is a part of the Theory with which every appearance of the surface
may be compared. I am confident that it will stand the test of the most
rigid examination; and that nothing but the most inconsiderate judgment
may mistake a few appearances, which, when properly understood, instead
of forming any subject of objection to the Theory, will be found to
afford it every reasonable support or confirmation.

We have now seen, that in every quarter of the globe, and in every
climate of the earth, there is formed, by means of the decay of solid
rocks, and by the transportation of those moveable materials, that
beautiful system of mountains and valleys, of hills and plains, covered
with growing plants, and inhabited by animals. We have seen, that, with
this system of animal and vegetable economy, which depends on soil and
climate, there is also a system of moving water, poured upon the surface
of the earth[30], in the most beneficial manner possible for the use of
vegetation, and the preservation of our soil; and that this water is
gathered together again by running to the lowest place, in order to
avoid accumulation of water upon the surface, which would be noxious.

[Footnote 30: See Dissertations upon Subjects of Natural Philosophy, Part
I.]

It is in this manner that we first have streams or torrents, which only
run in times of rain. But the rain-water absorbed into the earth is made
to issue out in springs, which run perpetually, and which, gathering
together as they run, form rivulets, watering valleys, and delighting
the various inhabitants of this earth. The rivulets again are united in
their turn, and form those rivers which overflow our plains, and which
alternately bring permanent fertility and casual devastation to our
land. Those rivers, augmenting in their volume as they unite, pour at
last their mighty waters into the ocean; and thus is completed that
circulation of wholesome fluids, which the earth requires in order to be
a habitable world.

Our Theory farther shows, that in the ocean there is a s