﻿784 
  

   will 
  be 
  : 
  

  

  W 
  

  

  Dr. 
  J. 
  Kunz 
  on 
  the 
  Corpuscular 
  

  

  T 
  ' 
  

   = 
  *(Q'-Q) 
  + 
  *f 
  (o- 
  6 
  -cr«)^T 
  

  

  

  ■*srJ,.--5T 
  

  

  dT 
  

  

  N.\ 
  I 
  

  

  but 
  

  

  , 
  .4ar 
  mi 
  N„1 
  T 
  4 
  a 
  f 
  T 
  ' 
  "NT 
  

  

  hence 
  W 
  = 
  2*E. 
  

  

  The 
  work 
  done 
  by 
  the 
  current 
  i 
  under 
  the 
  influence 
  o£ 
  the 
  

   electromotive 
  force 
  E 
  in 
  unit 
  time 
  is 
  equal 
  to 
  the 
  heat 
  

   absorbed 
  in 
  the 
  circuit 
  in 
  the 
  same 
  time. 
  

  

  § 
  9. 
  Resistance 
  of 
  Alloys, 
  

  

  Lord 
  Rayleigh* 
  has 
  pointed 
  out 
  that 
  in 
  the 
  case 
  o£ 
  a 
  

   mixture 
  of 
  metals 
  there 
  is, 
  owing 
  to 
  their 
  thermoelectric 
  

   properties, 
  something 
  which 
  cannot 
  be 
  distinguished 
  by- 
  

   experiments 
  from 
  resistance, 
  and 
  which 
  is 
  absent 
  when 
  the 
  

   metals 
  are 
  pure. 
  Let 
  us 
  suppose 
  that 
  the 
  mixed 
  metals 
  are 
  

   arranged 
  in 
  thin 
  layers, 
  the 
  adjacent 
  layers 
  being 
  of 
  different 
  

   metals, 
  and 
  that 
  the 
  current 
  passes 
  through 
  the 
  body 
  at 
  right 
  

   angles 
  to 
  the 
  faces 
  of 
  the 
  layer. 
  When 
  a 
  current 
  passes 
  

  

  Fie. 
  5. 
  

  

  t, 
  

  

  across 
  the 
  junction 
  of 
  two 
  metals 
  there 
  is 
  absorption 
  or 
  pro- 
  

   duction 
  of 
  heat, 
  proportional 
  to 
  the 
  current 
  passing 
  across 
  

  

  * 
  Lord 
  Rayleigh, 
  Collected 
  Works, 
  vol. 
  iv. 
  p. 
  232. 
  

  

  