Analyfis of the Aiv. 3 1 1 



Experiments, relating to the nature of dige- 

 ftion, in a warmth equal to that of the fto- 

 mach; but have been hitherto prevented by 

 purfuing other Experiments. 



Thus we fee that all thefe mixtures do in 

 fermentation generate elaftick air; but thofe 

 which emit thick fumes, charg'd with ful- 

 phur, reforb more than was generated, in pro- 

 portion to the fulphureoufnefs and thicknefs 

 of thofe fumes. 



I have alfo fhewn in many of the forego- 

 ing Experiments, that plenty of true perma- 

 nent elaftick air is generated from the fer- 

 menting mixtures of acid and alkaline fub- 

 ftances, and efpecially from the fermentation 

 and diflblution of animal and vegetable bo- 

 dies, into whofe fubftances we fee it is in a 

 great proportion intimately and firmly incor- 

 porated; and confequcntly great quantities of 

 elaftick air muft be continually expended in 

 their production ; part of which does, we fee, 

 relume its elaftick quality, when briskly 

 thrown off from thofe bodies by fermentation 

 in the diflblution of their texture. But part 

 may probably never regain its elafticity, or at 

 leaft not in many centuries, that efpecially 

 which is incorporated into the more durable 

 parts of Animals and Vegetables. However, 



X 4 we 



