new inflammable Air or Gafls , &c. 415 
drop of aether occupies, which laft ingredient, when 
pure, feems to be an efTence of the inflammable princi- 
ple of the fpirit of wine, a pure phlogifton concentrated 
in the form of a liquid? Indeed the inflammable air from 
metals feems to be rather a compound of phlogifton and 
fome kind of elaftic permanent fluid than a pure inflam- 
mable fluid ; for this air, after having loft all its inflam- 
mability, by being kept a long while upon water, occu- 
pies ftill a confiderable fpace, and is then become phlo- 
gifticated air ; that is to fay, fuch an air as is not to be di- 
minilhed by nitrous air, or to be inflamed. 
Though I have no reafon to alter my former affection, 
that the force of gunpowder is proportionable to the fud- 
den extrication of a great quantity of the elaftic fluid 
generated in the moment of conflagration, and the ex- 
panfion of this fluid by heat, communicated to it in the 
fame moment of its extrication; and that the force of in- 
flammable exploflve air can only be proportionable to the 
fudden expanflon by heat in the moment of the inflam- 
mation (for no new extrication here takes place); yet i 
did not confider enough in the account the fudden- 
nefs of this expanflon, which may make a confiderable 
difference in the force of the explofion. And indeed 
the abovementioned experiments feem to demonftrate, 
that the inflammation of the compound of pure dephlo- 
I i i a gifticated 
