﻿680 
  

  

  Prof. 
  J. 
  J. 
  Thomson 
  on 
  

  

  - 
  

  

  Y=10. 
  

  

  V=15. 
  

  

  V=20. 
  

  

  V=25. 
  

  

  V 
  = 
  :;0. 
  

  

  1 
  11 
  

  

  1 
  75 
  

  

  2 
  56 
  

  

  n 
  

   82 
  

   62 
  

  

  43 
  

   27 
  

  

  n 
  

   81 
  

   68 
  

   50 
  

   43 
  

  

  n 
  

   81 
  

   72 
  

   58 
  

   50 
  

  

  n 
  

  

  SO 
  

   72 
  

   61 
  

   56 
  

  

  4 
  28 
  

  

  

  V=40. 
  

  

  N=100. 
  

  

  V=200. 
  

  

  V=300. 
  

  

  V=400. 
  

  

  82 
  

  

  81 
  

  

  81 
  

  

  81 
  

  

  81 
  

  

  78 
  

  

  80 
  

  

  80 
  

  

  80 
  

  

  81 
  

  

  68 
  

  

  78 
  

  

  76 
  

  

  79 
  

  

  80 
  

  

  63 
  

   1 
  

  

  76 
  

  

  79 
  

  

  80 
  

  

  80 
  

  

  The 
  figures 
  in 
  this 
  case 
  are 
  quite 
  different 
  from 
  those 
  for 
  

   hvdrogen. 
  AVe 
  see 
  that 
  for 
  voltages 
  over 
  100 
  the 
  charge 
  on 
  

   the 
  disk 
  is 
  not 
  appreciably 
  diminished 
  when 
  the 
  current 
  

   through 
  the 
  electromagnet 
  is 
  raised 
  from 
  1 
  up 
  to 
  4 
  amperes; 
  

   this 
  shows 
  that 
  the 
  number 
  of 
  ions 
  with 
  masses 
  comparable 
  

   with 
  those 
  of 
  a 
  hydrogen 
  atom 
  is 
  too 
  small 
  to 
  be 
  detected, 
  for 
  

   such 
  ions 
  under 
  a 
  field 
  of 
  100 
  volts 
  would 
  have 
  been 
  able 
  to 
  

   make 
  their 
  way 
  to 
  the 
  disk 
  against 
  a 
  magnetic 
  field 
  due 
  to 
  

   1 
  ampere, 
  but 
  not 
  that 
  due 
  to 
  2 
  amperes 
  or 
  more; 
  thus 
  if 
  

   these 
  had 
  been 
  present 
  in 
  any 
  considerable 
  number, 
  the 
  

   number 
  reaching 
  the 
  disk 
  when 
  i=l 
  would 
  have 
  been 
  appre- 
  

   ciably 
  greater 
  than 
  when 
  t 
  = 
  2. 
  

  

  The 
  fact 
  that 
  20 
  per 
  cent, 
  under 
  these 
  voltages 
  reach 
  the 
  

   Faraday 
  cylinder 
  is 
  due, 
  I 
  think, 
  to 
  the 
  obliquity 
  of 
  the 
  ions 
  

   as 
  they 
  come 
  through 
  the 
  hole, 
  and 
  to 
  the 
  diffusion 
  they 
  

   suffer 
  in 
  passing 
  through 
  the 
  gas. 
  Under 
  the 
  smaller 
  

   voltages 
  the 
  effect 
  of 
  the 
  magnitude 
  of 
  the 
  magnetic 
  field 
  is 
  

   very 
  apparent; 
  thus 
  until 
  the 
  voltage 
  is 
  above 
  20 
  the 
  majority 
  

   of 
  them 
  are 
  stopped 
  by 
  a 
  field 
  of 
  4 
  amperes, 
  indicating 
  that 
  

   the 
  mass 
  of 
  the 
  majority 
  of 
  the 
  ions 
  is 
  not 
  greater 
  than 
  

   480/20 
  or 
  24 
  times 
  the 
  mass 
  of 
  an 
  atom 
  of 
  hydrogen. 
  In 
  

   fact 
  that 
  the 
  majority 
  of 
  the 
  ions 
  have 
  masses 
  comparable 
  

   with 
  that 
  of 
  the 
  molecule 
  of 
  oxygen, 
  and 
  are 
  not 
  aggregates 
  

   of 
  several 
  molecules. 
  

  

  Though 
  the 
  preceding 
  list 
  shows 
  that 
  the 
  number 
  of 
  ordinary 
  

   hydrogen 
  ions 
  in 
  this 
  gas 
  was 
  too 
  small 
  to 
  be 
  detected, 
  yet 
  

   when 
  the 
  Canalstrahlen 
  produced 
  in 
  a 
  tube 
  in 
  direct 
  con- 
  

   nexion 
  with 
  the 
  one 
  in 
  which 
  the 
  ionization 
  occurred 
  were 
  

   investigated 
  they 
  were 
  found 
  to 
  be 
  well 
  developed, 
  and 
  to 
  

  

  