ATMOSPHERICx\L AIR. i- 



clear, it f^ill yielded much more air than difrilled water. 

 Probably fome calcareous matter diffolved in the water 

 was decompofed in this procefs, and the air contained in 

 it had increafed the bulk of that which had been produced 

 by means of the water. 



Having, in the manner above -mentioned, foQnd an 

 eafy methoti of expelling from a quantity of water all the 

 air contained in it, I wiihed to know what would be the 

 refult of making it imbibe different kinds, and various 

 mixtures, of air. I had before found that water deprived, 

 of its air by boiling would imbibe any kind of air, and 

 that when this air was again expelled by heat, the quality 

 of it was not changed ; but I could now both expel the air 

 more effectually, and make it imbibe any particular kind 

 of air with more certainty and expedition. For this 

 purpofe, having fiift expelled the air, by removing the 

 preffure of the atmofphere in the manner defcribed 

 above, I inclined tbevelfel, laying it in a pofition nearly 

 horizontal, with the end of the tube immerfed in a bafon 

 of mercury ; and then having introduced the air that I 

 wiflied it to imbibe, I gently agitated the velTel, and the 

 preffure of the atmofphere being now removed, the water 

 would pretty foon faturate itfelf with the air. After this, 

 the veffel being placed upright, the air which it had im- 

 bibed was prefently difcharged, without any application 

 of heat. 



In this method, beginning wuth atmofpherical air, 

 which confifts of a mixture of dephlogiflicated and phlo- 

 gifticated air, 1 found that water imbibes the former in 

 preference to the latter, but not wholly unmixed with it. 

 Having made 45 ounces of diftilled water free from air, 

 I put to it ■z^ ounce meafures of atmofpherical air, of 

 which, by agitation, it imbibed three fourths of a mea- 

 fure, when the remaining two ounce meafures were 

 found to be of the flandard of 1.15 inflcad of i.oi 

 C which 



