﻿COHEN. 
  

  

  Fig. 
  9. 
  

  

  100 
  

  

  300 
  

  

  Effects 
  of 
  resistance 
  in 
  single 
  action 
  circuit. 
  

  

  Fig. 
  10. 
  

  

  MTO' 
  

  

  Double 
  action 
  circuit 
  wayes. 
  

  

  