188 



THE ROYAL SOCIETY OF CANADA 



Figure 1 



turned and the lignite exposed to the gas until the pressure, read on 

 the manometer L, became constant. Since its density had been 

 determined, the volume of the lignite in the tube X could be calcu- 

 lated. Subtracting this from the volume of the empty apparatus, 

 which had been previously determined, the volume of the unadsorbed 

 gas in the apparatus is found which, together with the pressure will 

 give the amount not absorbed. The difference between this amount 

 and the amount of gas admitted was considered to be the amount 

 adsorbed. 



In all measurements given below, the volumes of gas are reduced 

 to standard temperature and pressure. 



1. Time Required for Equilibrium 



In order to obtain some idea as to the time required for equilib- 

 rium between the adsorbed and unadsorbed gas to be attained, a 

 measured amount of dry air was admitted to the apparatus and al- 



