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ROYAL SOCIETY OF CANADA 



(a) The Charcoal Surface Exposed ta the Emanation. 



The ratio of tJtie surface to the mass of a particle of any material 

 increases as the size of the particle decreases; hence, one lot of char- 

 coal, equal in mass to a second lot, will have a greater or less absorbing 

 surface than the second, according as the size of its grains is smaller 

 or larger than the size of the grains of the second. 



TABLE L (Fig. 2). 



Multiply current by 616 x 10~^ for amperes. 



In an experiment, the results of which are given here in Table I and 

 Fig. 2, the i-q curves were taken for three equal mi.sses, 2.17 gms., of 

 the same sample of cocoanut charcoal of différent size grains. I is the 

 cuiTe of non-absorption, II is the curve for grains which were just 



