﻿Phil. 
  Mag, 
  Ser. 
  6. 
  Vol. 
  26, 
  PL 
  XVIII. 
  

   Fig. 
  5. 
  

  

  § 
  70 
  

   | 
  

  

  | 
  60 
  

  

  ^ 
  

  

  fos 
  

  

  A/EGAT/V£ 
  

  

  150 
  300 
  450 
  600 
  750 
  900 
  1050 
  1200 
  1350 
  1500 
  

  

  F/ELD 
  FOTENT/AL 
  fNl/OlTb. 
  

  

  Fig. 
  9. 
  

  

  Current 
  (a*bit*ary 
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  400 
  

  

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