3 ANALYSISoF 



were confined in a phial containing pieces of riifted iron 

 from the 1 8th of Augulf to the 6th of Odober, when it 

 was reduced to 9 ounce meafures, and was but flightly 

 inflammable. The iron, from being red, was then be- 

 come of a very dark colour. Another quantity of inlhim- 

 mable air treated in the fame manner from, 1 beheve, the 

 6th of Oftober, was in the 2d of December found to be 

 completely phlogifticated. In thefe experiments the iron 

 and the air were confined by water. Afterwards, put- 

 ting 7 ounce meafures of inflammable air to pieces of 

 rufted iron confined by mercury, it was, in about a 

 week, almoft wholly abforbed. 1 then filled up the veffel 

 again with inflammable air, and when the diminution 

 proceeded no farther, I examined it, and found 5 ounce 

 meafures of air completely phlogifticated. 



Charcoal, as well as phlogillicated air, I have no 

 doubt, contains the element of dephlogifticated air, as 

 well as phlogirton, fince by its union with ffeam it 

 takes the form of fixed air, as well as that of inflamma- 

 ble air, and one element in the compofition of fixed air 

 is dephlogifticated air. And when I made hot charcoal 

 imbibe inflammable air by introducing pieces of it into 

 jars of this air confined by mercury, and afterwards ex- 

 pelled it by plunging the charcoal in water, that which 

 came out of it was phlogillicated air. Yet I think I re- 

 colled that the refult of this experiment has fometimes 

 been inflammable air, the fame that the charcoal had im- 

 bibed. 



1 know of no cafe of the fimple abforption of air, but 

 which, like that by water, rcfpeds all kinds of air, 

 though with a preference of that which is dephlogiftica- 

 ted ; but not fo as to take this kind only, and leave all the 

 phlogifticated air that was mixed with it. Otherwife it 

 would have been in our power to afcertain with exadnefs 

 the real proportion of both the kinds of air in the atrao- 

 4 fphere 



