on the Vapour of Acids « > 
Diftilled vinegar fubmitted to this procefs yielded air two- 
thirds of. which was fixed air, and the reft inflammable : ex- 
pending 2 oz. 19 dw. o gr. of the acid, I got 1 oz. 19 dw. o gr* 
of a liquor which had a more pungent fmejl than it had before 
diftillation. It had alfo fome black matter in it, and fome of 
the fame remained at the bottom of the retort when the liquor 
was evaporated to drynefs. The air I received was 90 oz« 
meafures. 
Alkaline air is converted into inflammable air in this procefs 
as well as by the electric fpark, but by no means* I think, in 
fo great a degree, I put 2 oz. 10 dw. o gr. of water pretty 
ftrongly impregnated with alkaline air into the retort, and 
heating it, fent the vapour through the hot tube ; when I col- 
lected 2 oz. 3 dw. o gr. of liquor, which had a difagreeable 
empyreumatic fmell, as w^ell as that of a volatile alkali, and it 
was quite opaque with a black matter , which fubfided to the 
bottom of the v.eflel. Alfo the tube through which the air 
and vapour had been conveyed was left quite black, as men- 
tioned above. One of the junctures of the apparatus not 
having been air-tight, I did not colleCt all the air, but it came 
only at the beginning of the procefs, and before the tube be- 
came black, or any liquor was diftilled, and it was all ftrongly 
inflammable. 
I (hall now recite a few experiments of a different kind from 
thofe that have been mentioned above, and more immediately 
relating to the doCtrine of phlogifton. 
It is faid, by thofe who do not admit the doCtrine of phlo- 
gifton, that the metals are Ample fubftances, which, having a 
ftrong affinity to dephlogifticated air, imbibe it when they be- 
come calces, without parting with any thing. But that fome- 
thing is really parted with in the calcination (as they will call 
U u 2 it) 
