Vol. Ill, No- 5.] Note on the absorption of gases, etc. 237 



[N.S.-] 



exact determinations of the relationship between the pressure and 

 the quantity of gas absorbed had been made, I was obliged to 

 make some measurements for myself. The details of these experi- 

 ments will be found in the "Proceedings" of the Royal Society, 



Vol. 78, A. , 



The relationship between pressure and ' concentration/ the 

 latter expressed as the quantity of carbon dioxide pe7' cent, absoibed 

 by the charcoal, at 100'', 6r, 35°, 0°, and -78° C are represented 

 by the curves in Fig. 1, The equation for these curves may con- 

 veniently be wtntten in the form 



^ 



n^^p/x = Constant, 



where p is the pressure of the gas, and x is the concentration. The 

 value of n increases as the temperature falls, and tends towards 

 unity at moderately high 'temperatures, when the e xpression 

 becomes 



p/x 5= Constant. 



C 



J 



s 



"St 



1 



Fig. 2. — Absorption of water by cotton and wool. 



