394 



On Ionization by Spraying. 



the outer cylinder was charged to 360 volts, the following 

 results were obtained : — 



Table III. 



Electrometer. 



, Potential difference 360 volts. 





+ions. 



—ions. 



| 



Eatio. 



Water 



Ether 



Chloroform ... 

 Acetic acid ... 

 Benzine 



82 



420 



120 



600 



3 



112 

 730 

 120 

 630 



2 



1-3 

 1-7 



ro 



10 



These results agree in the main with those found with the 

 electroscope. The negative ions from ether and water are in 

 excess of the positive, and to the same extent as before. The 

 low ionization of benzine spray is again remarkable. The 

 figures for chloroform are lower in proportion than those 

 found with the electroscope, but I have found chloroform 

 rather erratic, possibly on account of impurity. The liquids 

 used have not been dehydrated, and therefore there may be 

 present some of the mobile ions due to water. I have not 

 yet discovered the cause of the inequality in the number of 

 negative and positive ions of water. It does not seem pos- 

 sible to attribute it to the different velocities of the two ions. 

 The inequality of the number of negative and positive ions 

 in the atmosphere, as detected by Ebert's apparatus, is well 

 known. 



On another occasion with a different testing vessel the 

 results obtained were 



Table IV. 





-f ions. 



—ions. 



Ratio. 



Water 



31 



235 



420 



730 



too small to measure 



42 

 295 



470 

 750 



1-3 



1-25 



11 



1-0 



Ether 



Arnyl Alcohol . . . 

 Ethyl Alcohol ... 

 Cineol 





In this case it will be seen that the ionization from amyl 

 alcohol was 10 times as great as from water, and from ethyl 

 alcohol 20 times as great. 



