PHYSICAL ann LITERARY. 79 
impreffed upon it, and is utterly incapable of 
‘producing any kind of motion. The only 
immediate caufe of the motion, being the 
active force of the animal which prefles the 
medium one way, and its own body the o- 
ther way, as might be particularly fhown in 
every kind of progreffion, if it were thought 
needful. 
Tuus, upon the moft attentive examina- 
tion into the ftate and condition of body at 
ref{t, we have found it to be perfectly inert or 
ina@ive. Body in motion next demands our 
confideration. Suppofing a body once put in 
motion by fome agent or other, it behooves us 
to follow it out, and enquire what happens 
to it on this change of its {tate. An extend- 
ed, impenetrable, ina¢tive fubftance has re- 
ceived a motion: Will it inftantly ftop when 
the immediate influence of the active power 
ceafes? or will it perfevere in its new ftate? 
From what commonly happens in_ the 
motions of bodies, their gradual lofs of force 
and returning toa ftate of reft; people con- 
_ tract an early propoffeffion, and are ready to 
_ imagine, that reft is the proper ftate of body. 
But a diligent review of all the circumftan- 
b ces, foon difcovers, that bady is equally in- 
ey different 
