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about two days the fermentation feemed intirely over. 
The liquor fmelt very putrid, and was found to have 
loft 1 1 1 grains of its v¥eight. The fope leys had 
acquired a brcwnifh colour from the putrid vapours, 
and a mufty fmell. The air forced into the inverted 
bottle, and not abforbed by the fope leys, meafured 
6280 grains : the air left in the bent tube and ferment- 
ing bottle was 1100 grains; almoft all of which 
muft have been forced into the inverted bottles : fo 
that this unabforbed air is a mixture of about one part 
of common air and 4JL. of factitious air. 
This air was found to be inflammable; for a fmall 
phial being filled with 109 grain meafures of it, and 
301 of common air, which comes to the fame thing 
as 90 grains of pure factitious air, and 320 of com- 
mon air, it took fire on applying a piece of lighted 
paper, and went off with a gentle bounce, of much 
the fame degree of loudnefs as when the phial was 
filled with the laft mentioned quantities of inflam- 
mable air from zinc and common air. When the phial 
was filled with 297 grains of this air, and 113 of 
common air, i. e. with 245 of pure factitious air, and 
165 of common air, it went off with a gentle bounce 
on applying the lighted paper; but 1 think not fo 
loud as when the phial was filled with the laft- 
mentioned quantities of air from zinc and common 
air. 
55°° g rain meafures of this air, /. e. 4540 of pure 
factitious air, and 960 of common air, were forced 
into a piece of ox-gut furnifhed with a fmall brafs 
cock, which I find more convenient for trying the 
fpecific gravity of fmall quantities of air, than a 
bladder: the gut increafed 4*- grains in weight on 
2 forcing 
