﻿Positive 
  Electricity. 
  835 
  

  

  Experiments 
  were 
  also 
  made 
  with 
  the 
  retrograde 
  rajs, 
  and 
  

   it 
  was 
  found 
  that 
  the 
  velocity 
  o£ 
  these 
  was 
  also 
  practically 
  

   independent 
  o£ 
  the 
  strength 
  o£ 
  the 
  field 
  and 
  very 
  nearly 
  the 
  

   same 
  as 
  that 
  of 
  the 
  Canalstrahlen. 
  

  

  The 
  small 
  range 
  of 
  velocities 
  in 
  the 
  Canalstrahlen 
  is 
  

   explicable 
  if 
  we 
  suppose 
  that 
  the 
  rays 
  we 
  are 
  measuring 
  

   exist 
  originally 
  as 
  neutral 
  doublets 
  which 
  are 
  formed 
  by 
  the 
  

   combination 
  of 
  a 
  positive 
  unit 
  and 
  a 
  negative 
  corpuscle 
  ; 
  

   these 
  doublets 
  moving 
  towards 
  or 
  away 
  from 
  the 
  cathode, 
  

   the 
  direction 
  of 
  motion 
  being 
  approximately 
  at 
  right 
  angles- 
  

   to 
  the 
  cathode. 
  These 
  doublets 
  could 
  not 
  have 
  more 
  than 
  a 
  

   certain 
  amount 
  of 
  energy 
  ; 
  for 
  if 
  the 
  relative 
  velocity 
  of 
  the 
  

   carriers 
  of 
  the 
  positive 
  and 
  negative 
  charges 
  when 
  uncombined 
  

   exceeded 
  a 
  certain 
  value, 
  the 
  charges 
  would 
  fly 
  past 
  each 
  

   other 
  without 
  entering 
  into 
  combination 
  and 
  they 
  would 
  

   remain 
  dissociated 
  : 
  it 
  is 
  only 
  when 
  the 
  kinetic 
  energy 
  of 
  the 
  

   two 
  falls 
  below 
  a 
  certain 
  value 
  that 
  combination 
  will 
  take 
  

   place 
  ; 
  thus 
  there 
  will 
  be 
  a 
  superior 
  limit 
  to 
  the 
  energy 
  of 
  

   the 
  doublets. 
  The 
  doublets 
  which 
  we 
  investigate 
  when 
  we 
  

   measure 
  the 
  velocity 
  of 
  the 
  cathode 
  rays 
  are 
  those 
  vv^hich 
  

   dissociate 
  again 
  into 
  positive 
  and 
  negative 
  charges. 
  J^ow,, 
  

   as 
  the 
  kinetic 
  energy 
  of 
  the 
  doublet 
  decreases 
  it 
  gets 
  more 
  

   and 
  more 
  stable 
  and 
  less 
  likely 
  to 
  dissociate^ 
  and 
  when 
  it 
  

   ceases 
  to 
  dissociate 
  we 
  cannot 
  measure 
  the 
  velocity. 
  Thus 
  

   doublets 
  are 
  not 
  formed 
  possessing 
  energy 
  greater 
  than 
  a 
  

   certain 
  value 
  ; 
  on 
  the 
  other 
  hand, 
  they 
  are 
  not 
  split 
  up 
  if 
  the 
  

   energy 
  is 
  less 
  than 
  a 
  certain 
  value. 
  Thus 
  the 
  doublets 
  whose 
  

   velocity 
  we 
  can 
  determine 
  will 
  have 
  velocities 
  between 
  

   definite 
  limits 
  which 
  are 
  independent 
  of 
  the 
  strength 
  of 
  the 
  

   electric 
  field. 
  The 
  case 
  is 
  analoo-ous 
  to 
  that 
  of 
  a 
  gas 
  which 
  

   dissociates 
  as 
  the 
  temperature 
  is 
  raised 
  : 
  there 
  is 
  a 
  certain 
  

   range 
  of 
  temperature 
  in 
  which 
  there 
  is 
  appreciable, 
  but 
  not 
  

   complete 
  dissociation 
  ; 
  beyond 
  the 
  upper 
  limit 
  of 
  this 
  range 
  

   of 
  temperature 
  the 
  undissociated 
  molecules 
  are 
  too 
  few 
  to 
  be 
  

   detected 
  ; 
  beneath 
  the 
  lower 
  limit 
  the 
  products 
  of 
  dissociation 
  

   are 
  not 
  numerous 
  enough 
  to 
  be 
  appreciable. 
  

  

  The 
  properties 
  both 
  of 
  the 
  Canalstrahlen 
  and 
  the 
  retrograde 
  

   rays 
  could 
  also 
  be 
  explained 
  on 
  the 
  view 
  that 
  neutral 
  doublets 
  

   moving 
  with 
  high 
  velocities 
  are 
  given 
  out 
  by 
  the 
  molecules 
  

   of 
  the 
  gas 
  in 
  the 
  discharge-tube, 
  that 
  these 
  break 
  up 
  into 
  

   the 
  Canalstrahlen 
  and 
  the 
  retrograde 
  rays 
  ; 
  these 
  doublets 
  

   are 
  supposed 
  to 
  be 
  of 
  the 
  same 
  character 
  from 
  whatever 
  

   kind 
  of 
  gas 
  they 
  may 
  originate. 
  We 
  should, 
  however, 
  

   expect 
  that 
  these 
  doublets 
  shot 
  out 
  from 
  the 
  molecules 
  by 
  

   explosions 
  would 
  be 
  found 
  moving 
  in 
  other 
  directions 
  than 
  

   just 
  along 
  the 
  lines 
  of 
  force 
  in 
  the 
  tube, 
  which 
  seems 
  to- 
  

  

  