304 An itly/is of the Air. 



So that the 8 5 cubick inches of air, Experi- 

 ment 96, which I found upon meafuring was 

 abforbed by the Walton mineral and com- 

 pound Aquafortis , was the excefs of what 

 was abforbed by thofe fumes above what 

 was generated by the fermenting mixture. 



And the reafon is the fame in filings of 

 Iron and Spirit of Nitre, Experiment 94, 

 which alfo abforbed more than they generat- 

 ed, whether with or without v/ater : The rea* 

 fon of which will appear prefentiy. 



Hence alfo we fee the reafon why filing* 

 of Iron and compound Aquafortis in the 

 fame 94 Experiment abforbed air j and why 

 when mixed with an equal quantity of water 

 it moftly abforbed, but did fometimes gene- 

 rate, and then abforb again : And it was the 

 fame with Oil of Vitriol, filings of Iron and 

 Water, and New-caftle Coal and compound 

 Aquafortis and others : viz. At firft, when 

 the ferment was brisk, the abforbing fumes 

 lofe fafteft, whereby more air was abforbed 

 than generated 5 but as the ferment abated, to 

 fuch a degree as to be able ftili to generate 

 elaftick air, but not to fend forth a propor- 

 tionable quantity of fumes, in that cafe more 

 air would be generated than abforbed. 



And 



