98 BELL SYSTEM TECHNICAL JOURNAL 



140 



6 8 10 12 14 16 18 20 22 24 26 

 d IN CENTIMETERS 



Pig 15 — Breakdown-potentials vs. gapwidth, in air, at the frequencies indicated, 

 for the kinds of electrodes sketched in the figure and described in the text. (Kamp- 

 schulte.) 



