280 Analyfts of the Air. 
particles, as appears by Experiment 74, where 
224 times its bulk of air arofe from a quan- 
tity of Sal Tartar And for the fame reafon 
it is that common Nitre , when thrown into 
the Fire, flames, tho’ its Spirit will not, viz* 
becaufe there is much elaftick air in it, a$ 
appears from Experiment 72, as well as from 
the great quantity of it, generated in the 
firing of Gun-powder. 
The reafon why SalTartar , when thrown 
on li xt'Coahy does not detonize and flame 
like Nitre , (notwithftanding by Experiment 
7.4 plenty of elaftick particles did arife from 
it) is this, viz , becaufe by the fame Experi- 
ment, compared with Experiment 72, it is 
found, that a much more intonfe degree of 
heat was required to extricate the elaftick 
air from Sal Tartar , the more fix’d body 
than from Nitre 5 the great degree of Fire 
with which Sal Tartar is made, rendering 
the cohefion of its parts more firm : For it is 
well known that fire, inftead of difuniting, 
does in many cafes infeparably unite the parr s 
of bodies : And ‘hence it is that Tulvis 
Fulminans? which is a mixture of SalTartar , 
Nitre and fulphur, gives a greater cxplofion 
than Gunpowder : Becaufe the particles of 
ihc Sal Tartar , cohering more firmly in a 
fix’d 
