﻿292 
  Mr. 
  McClung 
  on 
  the 
  Rate 
  of 
  Recombination 
  of 
  

  

  mately 
  *125 
  ; 
  and 
  therefore 
  the 
  above 
  expression 
  is 
  a 
  fair 
  

   value 
  for 
  the 
  first 
  approximation. 
  

  

  •■•2 
  v^v 
  i+ 
  2^ 
  <* 
  ■ 
  

  

  • 
  -i( 
  i+ 
  ^)( 
  T+ 
  vB' 
  

  

  2d 
  + 
  Z 
  U 
  

  

  4:d\/q 
  cL 
  2d— 
  I 
  

  

  l_/2d 
  + 
  l 
  

   V 
  q 
  a 
  "2d 
  — 
  I 
  

  

  2d 
  N 
  2d 
  + 
  Z 
  

  

  2d 
  + 
  l 
  Q 
  2^ 
  — 
  2 
  

  

  2^ 
  N 
  

   2d-h 
  Q' 
  * 
  • 
  

  

  by 
  equations 
  (4) 
  and 
  (6) 
  ; 
  

   • 
  (8) 
  

  

  This 
  gives 
  a 
  fairly 
  close 
  approximation 
  for 
  the 
  time 
  taken 
  

   for 
  the 
  number 
  of 
  ions 
  in 
  the 
  given 
  volume 
  in 
  the 
  cylinder 
  to 
  

   fall 
  to 
  half 
  of 
  their 
  maximum 
  value. 
  

  

  Having 
  discussed 
  the 
  mathematical 
  theory, 
  we 
  are 
  now 
  in 
  

   a 
  position 
  to 
  give 
  some 
  experimental 
  results 
  in 
  support 
  of 
  the 
  

   above 
  theory. 
  

  

  Experimental 
  Proof 
  of 
  the 
  Law 
  of 
  Recombination. 
  

  

  We 
  have 
  endeavoured 
  to 
  establish 
  the 
  foregoing 
  theory 
  at 
  

   the 
  various 
  pressures 
  by 
  obtaining 
  experimental 
  curves 
  showing 
  

   the 
  relation 
  between 
  the 
  number 
  of 
  ions 
  and 
  the 
  corresponding 
  

   time-interval 
  after 
  the 
  cessation 
  of 
  the 
  rays 
  and 
  then 
  com- 
  

   paring 
  them 
  with 
  the 
  theoretical 
  values, 
  as 
  deduced 
  from 
  

   equation 
  (2). 
  Curves 
  were 
  obtained 
  for 
  different 
  pressures, 
  

   varying 
  from 
  three 
  atmospheres 
  to 
  '125 
  of 
  an 
  atmosphere. 
  

   A 
  considerable 
  number 
  of 
  such 
  experimental 
  curves 
  were 
  

   obtained, 
  some 
  of 
  which 
  are 
  shown 
  in 
  rigs. 
  4, 
  5, 
  6, 
  and 
  7. 
  

  

  In 
  these 
  curves, 
  the 
  ordinates 
  represent 
  deflexions, 
  which 
  

   are 
  proportional 
  to 
  n, 
  while 
  the 
  abscissae 
  represent 
  the 
  corre- 
  

   sponding 
  times 
  in 
  seconds. 
  The 
  experimental 
  points 
  in 
  each 
  

   curve 
  are 
  marked 
  with 
  a 
  cross, 
  while 
  the 
  theoretical 
  points 
  

  

  