﻿IIICHMOND, 
  

  

  Fig. 
  III. 
  — 
  Variation 
  of 
  the 
  striation 
  with 
  variation 
  ot 
  

   electrical 
  conditions. 
  

  

  (a) 
  

  

  ■68 
  mm. 
  

  

  (i) 
  

  

  •61 
  mm. 
  

  

  (0) 
  

  

  •84 
  mm. 
  

  

  {d) 
  

  

  •80 
  mm. 
  

  

  (e) 
  

  

  I'l 
  mm. 
  

  

  Figures 
  (a) 
  to 
  (e) 
  were 
  obtained 
  from 
  circuits 
  the 
  frequencies 
  of 
  the 
  oscillations 
  

   from 
  which 
  are 
  in 
  descending 
  order 
  of 
  magnitude. 
  The 
  mean 
  strioe-di 
  stances 
  are 
  

   written 
  on 
  the 
  right, 
  

  

  