conspicuous in the operations of this world, and often examined by
philosophers, is a power which has been still less understood, whether
with regard to its efficient or final cause. It has hitherto appeared
more like the accident of natural things, than the inherent property of
the mineral region. It is in this last light, however, that I wish to
exhibit it, as a great power acting a material part in the operations of
the globe, and as an essential part in the constitution of this world.

We have thus surveyed the machine in general, with those moving powers,
by which its operations, diversified almost _ad infinitum_, are
performed. Let us now confine our view, more particularly, to that part
of the machine on which we dwell, that so we may consider the natural
consequences of those operations which, being within our view, we are
better qualified to examine.

This subject is important to the human race, to the possessor of this
world, to the intelligent being Man, who foresees events to come, and
who, in contemplating his future interest, is led to inquire concerning
causes, in order that he may judge of events which otherwise he could
not know.

If, in pursuing this object, we employ our skill in research, not in
forming vain conjectures; and if _data_ are to be found, on which
Science may form just conclusions, we should not long remain in
ignorance with respect to the natural history of this earth, a subject
on which hitherto opinion only, and not evidence, has decided: For in no
subject, perhaps, is there naturally less defect of evidence, although
philosophers, led by prejudice, or misguided by false theory, may have
neglected to employ that light by which they should have seen the system
of this world.

But to proceed in pursuing a little farther our general or preparatory
ideas. A solid body of land could not have answered the purpose of a
habitable world; for, a soil is necessary to the growth of plants; and a
soil is nothing but the materials collected from the destruction of the
solid land. Therefore, the surface of this land, inhabited by man,
and covered with plants and animals, is made by nature to decay, in
dissolving from that hard and, compact state in which it is found below
the soil; and this soil is necessarily washed away, by the continual
circulation of the water, running from the summits of the mountains
towards the general receptacle of that fluid. The heights of our land
are thus levelled w