﻿Ionization 
  in 
  va^noiis 
  Gases, 
  889 
  

  

  Thus 
  the 
  contribution 
  of 
  the 
  carbon 
  atom 
  to 
  molecular 
  

   ionization 
  is, 
  in 
  this 
  series 
  of 
  compounds, 
  only 
  '42. 
  

  

  The 
  ionizations 
  of 
  three 
  alcohols 
  are 
  given 
  by 
  Kleeman 
  : 
  — 
  

  

  Compound. 
  Ionization. 
  Difference. 
  

  

  CH3HO 
  1-74T 
  .^.^ 
  

  

  CoHsHO 
  2-46^ 
  

  

  1 
  1-94 
  

  

  C4H9HO 
  4-40 
  J 
  

  

  Mean 
  value 
  of 
  contribution 
  of 
  (C 
  + 
  2H)= 
  '89 
  

  

  Reference 
  back 
  to 
  the 
  number 
  deduced 
  for 
  the 
  contribution 
  

   of 
  the 
  same 
  group 
  to 
  the 
  ionization 
  of 
  the 
  paraffins 
  (i. 
  e, 
  '92) 
  

   shows 
  good 
  agreement. 
  

  

  But 
  the 
  ionization 
  values 
  of 
  the 
  two 
  alkyi 
  iodides 
  CH3l(3*43) 
  

   and 
  02^51(4-00) 
  indicate 
  a 
  contribution 
  by 
  the 
  group 
  (C 
  + 
  2H) 
  

   of 
  only 
  '57. 
  

  

  In 
  the 
  case 
  of 
  the 
  series 
  O2, 
  2]Si 
  0, 
  2N2O, 
  no 
  simple 
  additive 
  

   law 
  is 
  followed. 
  

  

  The 
  conclusions 
  to 
  be 
  drawn 
  seem 
  to 
  be 
  (1) 
  that 
  the 
  con- 
  

   tribution 
  of 
  a 
  constituent 
  atom 
  to 
  the 
  molecular 
  ionization 
  

   of 
  the 
  compound 
  is 
  not 
  constant, 
  but 
  depends 
  on 
  the 
  chemical 
  

   bond 
  or 
  on 
  the 
  proximity 
  of 
  its 
  companion 
  atoms, 
  or 
  on 
  both; 
  

   (2) 
  that 
  in 
  a 
  series 
  of 
  compounds 
  in 
  which 
  each 
  member 
  is 
  

   formed 
  by 
  adding 
  the 
  same 
  atom 
  or 
  group 
  of 
  atoms 
  to 
  the 
  

   molecule 
  of 
  the 
  preceding 
  member, 
  a 
  sort 
  of 
  additive 
  law 
  is 
  

   sometimes 
  closely 
  followed 
  ; 
  (3) 
  but 
  that 
  the 
  contribution 
  of 
  

   the 
  same 
  atom 
  or 
  group 
  of 
  atoms 
  in 
  different 
  series 
  is 
  not 
  

   usually 
  the 
  same. 
  

  

  Before 
  more 
  definite 
  statements 
  can 
  be 
  made, 
  still 
  further 
  

   data 
  are 
  required. 
  A 
  promising 
  source 
  of 
  information 
  would 
  

   seem 
  to 
  be 
  a 
  systematic 
  study 
  of 
  ionization 
  in 
  other 
  simple 
  

   homologous 
  series 
  such 
  as 
  those 
  of 
  the 
  defines 
  and 
  acetylenes. 
  

   Such 
  an 
  investigation 
  would 
  prove 
  useful 
  in 
  developing 
  a 
  

   subject 
  which 
  may 
  add 
  considerably 
  to 
  our 
  knowledge 
  of 
  

   the 
  mechanism 
  of 
  ionization. 
  

  

  The 
  writer 
  is 
  under 
  the 
  greatest 
  obligation 
  to 
  Professor 
  

   Sir 
  J. 
  J. 
  Thomson 
  both 
  for 
  his 
  interest 
  in 
  the 
  work 
  and 
  

   for 
  his 
  kind 
  permission 
  to 
  carry 
  it 
  out 
  in 
  the 
  Cavendish 
  

   Laboratory. 
  

  

  Bangalore, 
  18th 
  Feb. 
  1909. 
  

  

  