﻿476 
  Mr. 
  J. 
  S. 
  Townsend 
  on 
  Applications 
  oj 
  

  

  when 
  the 
  gas 
  is 
  contained 
  between 
  two 
  parallel 
  plates 
  at 
  a 
  

   distance 
  a 
  apart 
  ; 
  

  

  when 
  the 
  gas 
  is 
  contained 
  inside 
  a 
  cylinder 
  of 
  radius 
  a 
  ; 
  

   and 
  

  

  7r-ra- 
  

  

  Kt 
  

  

  e 
  «' 
  J 
  

  

  7T 
  2 
  _._. 
  M 
  2 
  

  

  n 
  = 
  \ 
  

  

  ir 
  

  

  when 
  the 
  gas 
  is 
  contained 
  inside 
  a 
  sphere 
  of 
  radius 
  a, 
  

  

  , 
  300/) 
  V 
  

   where 
  /<•= 
  — 
  ^ 
  

  

  These 
  equations 
  show 
  how 
  much 
  more 
  rapidly 
  the 
  con- 
  

   ductivity 
  is 
  destroyed 
  in 
  smaller 
  vessels 
  than 
  in 
  larger 
  

   ones. 
  

  

  Let 
  us 
  take 
  the 
  case 
  of 
  oxygen 
  which 
  has 
  been 
  made 
  a 
  con- 
  

   ductor 
  by 
  Rontgen 
  rays 
  ; 
  let 
  the 
  charge 
  on 
  each 
  carrier 
  be 
  

   x 
  times 
  the 
  charge 
  that 
  an 
  atom 
  of 
  oxygen 
  carries 
  in 
  electro- 
  

   lysis, 
  which 
  we 
  will 
  denote 
  by 
  E. 
  

  

  One 
  electromagnetic 
  unit 
  of 
  quantity 
  evolves 
  1*2 
  cub. 
  cent, 
  

   of 
  hydrogen 
  and 
  "6 
  cub. 
  cent, 
  of 
  oxygen 
  from 
  an 
  electrolytic 
  

   cell, 
  at 
  ordinary 
  temperature 
  and 
  pressure 
  ^o 
  =10 
  6 
  . 
  

  

  The 
  number 
  of 
  atoms 
  in 
  '6 
  cub. 
  cent, 
  is 
  2Na, 
  (6), 
  and 
  the 
  

   quantity 
  of 
  electricity 
  that 
  they 
  carry 
  is 
  \ 
  an 
  electromagnetic 
  

   unit, 
  or 
  § 
  10 
  10 
  electrostatic 
  units. 
  

  

  Hence 
  

  

  3 
  If) 
  10 
  

  

  L2NE=g-10 
  10 
  or 
  NE 
  = 
  ±4, 
  

  

  so 
  that 
  Ne 
  = 
  

  

  2 
  — 
  ~ 
  «~ 
  . 
  8 
  

   •8 
  

  

  The 
  velocity 
  of 
  the 
  carrier 
  under 
  an 
  electromotive 
  force 
  of 
  

   a 
  volt 
  per 
  centimetre 
  is 
  (E. 
  Rutherford, 
  Phil. 
  Mag. 
  1897, 
  

   vol. 
  xliv.) 
  1*6 
  centim. 
  per 
  second 
  ; 
  so 
  that 
  

  

  300xl0 
  6 
  xl-6x-8 
  3-84 
  

   *" 
  tflO 
  10 
  " 
  x 
  

  

  6. 
  Let 
  us 
  consider 
  more 
  particularly 
  the 
  second 
  case, 
  which 
  

   would 
  apply 
  to 
  a 
  conducting 
  gas 
  passing 
  along 
  tubing, 
  and 
  

   find 
  what 
  the 
  loss 
  of 
  conductivity 
  of 
  Rontgenized 
  oxygen 
  

   will 
  be 
  in 
  passing 
  along 
  a 
  tube, 
  10 
  centim. 
  long 
  and 
  1 
  

   millim. 
  radius, 
  at 
  the 
  rate 
  of 
  100 
  centim. 
  a 
  second. 
  

  

  For 
  simplicity 
  we 
  will 
  suppose 
  that 
  the 
  velocity 
  is 
  uniform, 
  

  

  