﻿788 
  Corpuscular 
  Theory 
  of 
  the 
  Thermoelectric 
  Forces. 
  

  

  The 
  actual 
  electric 
  conductivity 
  o£ 
  the 
  alloy 
  considered 
  is 
  

   equal 
  to 
  13*58 
  . 
  10 
  4 
  , 
  its 
  specific 
  resistance 
  therefore 
  7*4 
  . 
  10~ 
  6 
  ; 
  

   thus, 
  the 
  actual 
  resistance 
  is 
  very 
  nearly 
  twice 
  as 
  large 
  as 
  

   that 
  calculated 
  from 
  the 
  mixture 
  formula. 
  The 
  false 
  re- 
  

   sistance 
  g>' 
  = 
  5'5 
  . 
  10 
  -11 
  is 
  exceedingly 
  small 
  in 
  comparison 
  

   with 
  the 
  difference 
  between 
  the 
  actual 
  and 
  the 
  calculated 
  

   resistance. 
  

  

  We 
  shall 
  now 
  consider 
  an 
  alloy 
  made 
  up 
  of 
  09*3 
  gr. 
  copper 
  

   and 
  0*7 
  gr. 
  zinc. 
  Using 
  the 
  same 
  notation 
  as 
  before 
  we 
  get 
  

  

  />1 
  = 
  n'ocV 
  -+- 
  =26 
  + 
  0-95, 
  

  

  p 
  3 
  =0-99, 
  Pi 
  Pa 
  

  

  ^_ 
  2-62. 
  IP-* 
  

  

  w 
  3.273* 
  26-95 
  - 
  iiJ 
  * 
  iU 
  > 
  

  

  <*/= 
  1-19. 
  10- 
  10 
  . 
  4-2. 
  10 
  7 
  , 
  

  

  o/= 
  5 
  . 
  10~ 
  3 
  absolute 
  unit, 
  

  

  a,'= 
  5 
  . 
  10- 
  3 
  . 
  10- 
  9 
  = 
  5 
  . 
  10- 
  12 
  ohm. 
  

  

  The 
  mean 
  resistance 
  would 
  be: 
  

  

  lO" 
  6 
  (1-6 
  . 
  0-99 
  + 
  6-2 
  . 
  0-01) 
  =1-64 
  . 
  10" 
  6 
  . 
  

  

  But 
  the 
  actual 
  conductivity 
  is 
  equal 
  to 
  54*56 
  . 
  10 
  4 
  ; 
  therefore 
  

   the 
  actual 
  specific 
  resistance 
  is 
  equal 
  to 
  1*84 
  . 
  10~ 
  6 
  . 
  Here 
  

   again 
  the 
  actual 
  resistance 
  is 
  found 
  to 
  be 
  larger 
  than 
  the 
  

   calculated 
  one, 
  by 
  an 
  amount 
  of 
  quite 
  a 
  different 
  order 
  of 
  

   magnitude 
  from 
  the 
  false 
  resistance. 
  

  

  The 
  last 
  example 
  may 
  be 
  an 
  alloy 
  composed 
  of 
  equal 
  

   volumes 
  of 
  copper 
  and 
  platinum. 
  The 
  thermal 
  conductivity 
  

   of 
  platinum 
  k 
  t 
  is 
  equal 
  to 
  0*17, 
  the 
  electric 
  conductivity 
  

   9-2.10 
  4 
  , 
  the 
  specific 
  resistance 
  10'8 
  . 
  10~ 
  6 
  . 
  The 
  Peltier 
  

   effect 
  between 
  the 
  two 
  metals 
  is 
  equal 
  to 
  Q! 
  = 
  8*9 
  . 
  10 
  — 
  4 
  . 
  

  

  Q! 
  2 
  = 
  79.10- 
  8 
  

  

  ^ 
  + 
  ^ 
  =0-17.2 
  + 
  0-94.2 
  = 
  2-22. 
  

   Pi 
  Pa 
  

   The 
  false 
  resistance 
  would 
  be 
  equal 
  to 
  

  

  , 
  1 
  79. 
  lO" 
  8 
  . 
  QK 
  ln 
  10 
  

   " 
  = 
  3* 
  3. 
  273. 
  2-22 
  =4 
  ' 
  35 
  ' 
  10 
  -" 
  

  

  ©' 
  = 
  4*35 
  . 
  10- 
  10 
  . 
  4*2 
  . 
  10 
  7 
  = 
  l-82 
  . 
  10" 
  2 
  , 
  

  

  o>'= 
  1-82. 
  10- 
  11 
  ohm. 
  

  

  In 
  this 
  case 
  we 
  shall 
  calculate 
  this 
  false 
  resistance 
  from 
  

   the 
  first 
  formula 
  given 
  by 
  Lord 
  Rayleigh: 
  

  

  o,' 
  = 
  273^(- 
  1 
  + 
  - 
  2 
  )" 
  1 
  

   \Pi 
  Pt 
  I 
  > 
  

  

  