Ionization by Spraying. 



389 



Potassium iodide, potassium sulphate, silver nitrate, 

 fluorescene and water, and cineol, gave effects small com- 

 pared with distilled water. 



The relationship between ionization and strength o£ solution 

 is given in fig. 6, where abscissae denote percentage strength 

 of solution, and ordinates the total ionization. A similar 

 curve was obtained for solutions of salt (NaCl) . It is true 

 for spraying, as J. J. Thomson also found when bubbling air 

 through gases, that the presence of minute quantities of salt 

 diminishes appreciably the number of ions obtained from 

 water. 



Fig. 6. 



E EL 1 1 ! 



Percent, strength salt 



solution, co u stic soda 



I have sent a powerful air-current through cotton-wool, 



soaked with water or ether, in order to detect ionization due 



to evaporation. None was found, and the test was delicate. 



y Rays and Spray. 



The joint effect of the y rays from radium, and of spray 



from distilled water, was next tested. 



Water sprav alone 10*1 -,. r ■ • . 



\ J . n >ob divisions a minute 



7 rays alone 46 J 



Spray and rays together ... 60 „ „ 



Again with spray from methyl alcohol, and with y rays, 



the readings obtained were in the following proportions : — 



Spray alone 114~1 -. ~ ~ 



y rays alone 51 J 



Spray and rays 140 



It will be seen that the effects of spray and y rays together 



are almost the sum of their independent ionization. 



