© PHYSICAL ann LITERARY. 329 
for the oil of ‘vitriol expels any other acid, 
‘but canuot be diflodged by any of the reft. 
A volatile alcaline falt is expelled from its 
‘union with an acid, by a fixt alcaline, but not 
contraryways. 
General Scholium. 
We can have no other idea of a folid or 
‘confiftent body in general, as diftinguifhed 
from a fluid, than that the parts of a folid 
cohere together by fome power, which re- 
tains the particles in their fituations, with re- 
{pect to one another, and makes them to 
a their feparation or divifion, till that 
power is overcome by a fuperior force. 
*) WueEw we obferve that a certain fluid, as 
“water, poured upon a hard folid body, asa 
lump of falt- -petre, in fome hours, makes 
fach achange upon the lump, that it whol- 
ly difappears, if the glafs is fhaken a little, 
that i is, the falt is divided into particles, fo 
foal, that they efcape our fight, and are 
equally diftributed through the liquor, and 
Aulpended i in it; when we obferve this, I fay, 
owe cannot but conclude, that the particles of 
| es water 
