138 ESSAYS ann OBSERVATIONS 
fined to fluids, but is fuppofed to be an uni- 
verfal law of matter; a fmooth level furface 
muft not only be the confequence’ in fluids, 
but in folids, equally. Here then is a fair 
dilemma. We muft either acknowledge a 
{mooth level furface to be always found in 
fand, powder, and indeed in all loofe bodies, 
as well as in fluids; or confine this law of 
gravity to fluids. Can we remain a moment 
in doubt betwixt thefe two oppofites? we 
are certain that a fmooth level furface is not 
a neceflary property of folids. The gravity 
of a whole hill of fand, is but an affertion 
without evidence. What remains then, but 
that we adhere to the former, and rejeét the 
latter, except as to fluids? And thus our 
author luckily, tho’ without intention, has 
furnifhed a very convincing argument againft 
the univerfality of this fuppofed law of gravi- 
tation. Ifa f{mooth level furface is an effet | 
of this law, it follows clearly, that this law 
takes not place in folids, at leaft not univer- 
fally, as in fluids. 
It hath been judged a fubje& worthy “ to 
«be regreted that natural philofophers and 
«© mathematicians are not always well fkilled 
‘© in logics.” A fair comparifon alone can 
. fhow, 
