﻿Recomhination 
  of 
  Ions 
  in 
  Air 
  at 
  Dif 
  event 
  Temperatures. 
  329 
  

  

  constant, 
  on 
  the 
  assumption 
  that 
  the 
  ionizing 
  effect 
  of 
  the 
  

   rays 
  varies 
  inversely 
  as 
  the 
  square 
  of 
  the 
  distance 
  from 
  the 
  

   source, 
  mav 
  be 
  readily 
  obtained 
  as 
  follows 
  : 
  

  

  N= 
  ^^"ndv= 
  [^'\/^2i^'rT-o;)r\lr=lyyj3-^[r^ 
  

  

  4N 
  

   But 
  from 
  equation 
  (A) 
  

  

  9o 
  

  

  _ 
  (^■, 
  + 
  r0(,-/-n^)(47r-a>) 
  Q 
  _t^ 
  Q 
  

  

  where 
  Q 
  is 
  the 
  total 
  number 
  of 
  ions 
  produced 
  by 
  the 
  rays 
  

   per 
  second, 
  N 
  the 
  number 
  existing 
  in 
  the 
  gas 
  when 
  equilibrium 
  

   is 
  established, 
  and 
  o) 
  the 
  solid 
  angle 
  of 
  the 
  cone. 
  It 
  is 
  

   seen 
  that 
  K 
  is 
  a 
  constant 
  which 
  depends 
  only 
  upon 
  the 
  

   dimensions 
  of 
  the 
  chamber. 
  

  

  Experimental 
  Method 
  and 
  Arrangement 
  of 
  Apparatus. 
  

  

  The 
  method 
  used 
  in 
  this 
  investigation 
  was 
  essentially 
  the 
  

   same 
  as 
  that 
  employed 
  by 
  Hendren 
  {loc. 
  cit.), 
  

  

  Fi^. 
  1. 
  

  

  The 
  arrangement 
  of 
  the 
  apparatus 
  was 
  as 
  shown 
  in 
  

  

  fig.i. 
  

  

  