280 On the Absorption of Gases^. 



ground-stopper; in those with the more ab- 

 sorbable of the first class, I used an Eudiometer 

 tube properly graduated and of aperture so as 

 to be covered with the end of a finger. This 

 was filled with the gas and a small portion ex- 

 pelled by introducing a §olid body under 

 .w^ater; the quantity being noticed by the 

 quantity of water that entered on withdrawin^r 

 the solid body, the finger was applied to 

 the end and the water within agitated; thea 

 removing the finger for a moment under water, 

 an additional quantity of water entered, and 

 the agitation was repeated till no more water 

 would enter, when the quantity and quality 

 of the residuary gas was examined. In fact 

 .water could never be made to take its bulk of 

 any gas by this procedure ; but if it took -^-V, or 

 any other part, and the residuary gas was -rV 

 pure, then it was inferred that water would 

 take its bulk of that gas. The principle was 

 the same in using the phial ; only a small 

 quantity of tlie gas was admitted, and the 

 agitation was longer. 



There, are two very important facts contained 

 in the second article. The first , is, that the 

 quantity of gas abs.orbed is as the density or 

 pressure. — This was dicovered.by Mr. Wm. 

 Henry, before either he or I had formed any 

 Ibeory on tht? subject. 



