﻿390 Prof. H. A. McTaggart on the Electrification 



No. 3. 



Sign of 

 charge. 



Concentration. 



Equivalents 



per c.c. 



i~ 9 X5-7 



Diameter of 

 sphere 

 in mm. 



0-62 





0-53 





0-39 





0-17 





0-08 



No. 4. 



Concentration. 



Equivalents 



per c.c. 



Diameter of 

 sphere 

 in mm. 



Sign 

 charg 



»~ 9 X5-7 



0-71 









0-53 



— 





0-44 



— 





0-35 









0-32 



+ 





0-23 



+ 



Concentration. 



Equivalents 



per c.c. 



10- 9 x5-7 



No. 5. 



Diameter of 

 sphere 

 in mm. 



0-28 



0-17 



O08 



005 



Sign of 

 charge. 



It will be seen from the first four examples given that at 

 a concentration of 10~ 9 x 5*7 the change of sign occurs in 

 every case. Rarely, as in No. 5, and then only when the 

 original sphere was small, did the sign remain the same. 

 Even then the charge grew steadily less. In practically 

 every case the negative charge slowly decreases as the 

 bubble gets smaller, passes through zero, and increases to a 

 small positive value. 



