Anahyfts oj the Air. 279 
as I found by dropping a few drops of Spirit 
oi Nitre, oil of Fitriol, water, and fpittle 
on an Anvil s and then holding over thofe ^ 
drops a piece of Irm which had a white heat 
given it; upon ftriking down the hot Iren 
with a large Hammer, there was a very great 
cxplofion made by each of thofe liquors ; 
But frothy fpittle, which had air in it, made a 
louder explofion than water; which fhews 
that the vaft explofion of the Nitre and Sal 
Tartar, which are compofed of elaftick air 
particles, included in an acid Spirit, is owing 
to their united force. 
We may therefore from what has been 
faid, with good reafon conclude, that Fire is 
chiefly invigorated by the aftion and re-ac- 
tion of the acid fulphureous particles of the 
fuel, and the elaftick ones which arife and en- 
ter the jFire, either from the fhel in which 
they abound, or from the circumambient 
air: For by Experiment 103, and many 
others, acid fulphureous particles ad vi- 
goroufly on air ; andfinceadion and re-adion 
arc reciprocal, fo muft air on fulphur 3 and 
there is, we fee, plenty of both, as well in 
mineral as vegetable fuel, as alfo in animal 
fubftances, for which reafon they will burn. 
T 4 Bat 
