M'Clklland and Nolan — Ions produced by Bubbling Air. 59 



5 to 6 cms. of mercury was employed. The following numbers were 

 obtained : — 



Table V. 





•24 



•11 



• -044 



•013 





•24 



•12 



•043 



•020 





— 



•11 



•051 

 ■046 



•019 



• 



— 



— 



•016 





Means, 



24 



•11 



•046 



•019 



The ion of mobility "24 em. /sec. is obviously [the ion of mobility -21 of the 

 previous section. The ion of mobility - 11 corresponds to the ion of mobility 

 •12, which we were just able to detect with the apparatus used for the slower 

 ions. The other two ions of mobilities, '046 and '019, are the ions in 

 Tables I and II. 



The whole range of mobilities from i - 10 to -00015 has been examined, 

 and all the numbers can be placed in a certain definite number of classes. 

 The only effect of change of pressure or of variation in the time is to change 

 the percentages of the different classes : there is no change in the actual 

 value of the mobilities. The general means of 'all the numbers observed are 

 as follows : — 



1-10? '50 -31 -22 

 •0040 -0023 -0014 



•12 -049 -017 -0077 

 •00063 -00034 -00015 



All doubtful numbers are excluded in taking the means. About a dozen 

 observations not given in any of the previous sections are included. 



It is thought that the numbers given above represent the mobilities of all 

 the ions between the two extremes. 



Discussion of Results. 



The results obtained from these observations on the ions produced by 

 bubbling air through alcohol will be considered in conjunction with the work 

 described in the previous paper on the ionisation caused by bubbling air 

 through mercury, and also with the results of J. J. Nolan on the mobilities 

 of the ions produced by spraying distilled water.' In Table VI the mobilities 

 of the ions obtained with these three liquids are given. 



1 Proc. Roy. Irish Acad., vol. xxxiii, Sec. A (1916). Pi-oc. Roy. Soc, A, vol. xciv 

 (1917). 



R.I. A. PBOC, VOL. XXXIV, SECT. A. [10] 



