perpetual occupations have in part prevented, and may continue to prevent,
as long as he may be capable of revising it; he therefore begs of the
candid reader to accept of it in its present state, and to excuse any
inaccuracies of expression, or of conclusion, into which the intricacy of
his subject, the general imperfection of language, or the frailty he has in
common with other men, may have betrayed him; and from which he has not the
vanity to believe this treatise to be exempt.

* * * * *

ZOONOMIA.

* * * * *

SECT. I.

OF MOTION.

The whole of nature may be supposed to consist of two essences or
substances; one of which may be termed spirit, and the other matter. The
former of these possesses the power to commence or produce motion, and the
latter to receive and communicate it. So that motion, considered as a
cause, immediately precedes every effect; and, considered as an effect, it
immediately succeeds every cause.

The MOTIONS OF MATTER may be divided into two kinds, primary and secondary.
The secondary motions are those, which are given to or received from other
matter in motion. Their laws have been successfully investigated by
philosophers in their treatises on mechanic powers. These motions are
distinguished by this circumstance, that the velocity multiplied into the