[ x86 ] 
Firft, It is pretty univerfally allowed, that the 
add Particles have the Figure of fmall Needles } and 
that Alkali’s are fpheroidal or polyhedrous Bodies 
with a vaft Number of Bodies proper to admit the 
add Needles. 
Secondly , Experience fhews, that Salts are alka- 
lifcd by Fire, and that our Juices arc a! kalifed by 
Hear, &c. What can the iepeated Action of the 
Fire produce on Salts, in order to alkalife them ? It 
calcines them, blunts their Points, and hollows them 
with a vaft Number of Pores j and we fee with the 
naked Eye, that Calcination has this Effect on all 
Bodies. In a word, it converts an angular very folid 
Body into a very porous and light Spheroid ; and this 
Body is an Alkali by thefirft Suppofition. 
Thirdly , Calcination introduces, and generally 
leaves in the Pores of the calcined Body, after the 
Operation, a great Quantity of igneous Matter. This 
Matter is perceptible to the Senfes in the Lapis Bo 
nonienfis , which becomes a Phofphorus by Calcina- 
tion } in Lime-Stone, which by Calcination is fur- 
nifhed with fo great a Quantity of igneous Matter, 
that in the Effcrvefcence, which is raifed in it by 
throwing a* little Water on this Stone, you may 
kindle Sulphur or a Match by it. The Alcaline, or 
alcalized Salts alfo, that is, thofe which are calcined, 
have their Pores full of the igneous Matter. 
Fourthly , Such is the Nature of the igneous Mat- 
ter, that it tears afunder whatever oppofes its Paf- 
fage. 
