iy aig 
- PHYSICAL ann LITERARY. © 137 
exceed the particular weight which it hap- 
- opens to counteract.at anytime: and the fame 
table, at. different times, may fupport very 
different degrees of weight. But ftill itis 
-true, that the force exerted by this power 
-upon the body, can neither be greater nor 
Jefs than its weight, fince the reaction. bare- 
ly fupports the body without beginning mo- 
tion in it. If this needs any illuftration, we. 
__-may fuppofe a man to have a weight hanging 
at his hand, while at the fame time he. pref 
fes that hand upwards again{ft any fix’d body ; 
the force with which the hand al ieeat to, or 
is preffed againft the body, may be greater 
or lefs at pleafure ; but the force employed 
_.againft the weight, or that which directly op- 
_ pofes and counteracts it; muft exaétly he. e- 
qual to the weight itfelf. 
_ THE argument againft the law of action and 
. reastion may be made to conclude with equal 
_ force again{t the law of gravity itfelf; and, if 
it proves any thing at all, will even prove it 
impoffible that all terreftrial bodies fhould be 
endued with weight. Muratis mutandis, the 
‘reafoning proceeds thus. Admitting the law 
of gravity, a {mooth level furface muft be the 
confequence. And as the, law is not con- 
hes fined 
