16 



Proceedings of the Royal Irish Academy. 



by time, while the percentage of the total charge carried by that ion increases 

 rapidly. The total ionisatiou falls off very rapidly with time. This effect 

 may be ascribed to reeombiuation, which will of course be more active among 

 the more mobile ions. An increase in the percentage of the slowest ion is 

 therefore to be expected. 



Determination of the Mobilities. 

 The results of all experiments for the determination of the mobilities 

 of the first five classes are given in the following table. They are set down 

 without distinction of sign. In arriving at the mean values which are given 

 in the last line all numbers marked doubtful are excluded. Apart from these 

 the values found for classes 1 and 2 may be regarded as having all the same 



Table III. 

 Mohilities of Ions of First Five Classes. 





1 



2 



3 



4 



5 



•00031 



•00087 



•0036* 



•013* 





•04.5* 





31 



88 



39* 



•013* 





•048* 





33 



88 



43* 



■ -013* 





•040? 





33 



88 



45* 



•010? 





•060? 





34 



88 



45* 



•Oil? 









37 



88 



48* 



■016? 









37 



88 



31 











3S 



90 



33 











38 



93 



44 











39 



95 



53 











40 



107 



58 











40 

 40 



116 

 1-20 



52? 

















40 



131 











40 



131 



Ur 



classified Mobilities 







43 



88? 





•00065* 







44 







•00065* 







38? 







•00059? 







44? 











Means, 



•00038 



' •ooion 



■0G43 



•013 



•046 



