256 



WHITEHEAD— HIGH VOLTAGE CORONA IN AIR. 



termining the constancy of circuit and other experimental condi- 

 tions. The observations were all collected in groups corresponding 



■l-KlLOVOLTS PER CeNTIMETER 



Fig. 7. 



to approximately the same values of 8 for each particular size of 

 corona rod, and the values of £/8 and i/yjhr were calculated in 

 each case. Obviously E, the value of the surface electric intensity 



