﻿Positive 
  Ions 
  emitted 
  from 
  various 
  Hot 
  Bodies. 
  671 
  

   charge 
  to 
  be 
  

  

  3 
  R^ 
  ^ 
  ^^ 
  ir\ 
  on 
  

  

  e= 
  ,^ 
  » 
  -^=l'ODX 
  IQ--^ 
  E.s.u. 
  

  

  This 
  value 
  o£ 
  the 
  charge 
  should 
  be 
  in 
  error 
  by 
  not 
  more 
  

   than 
  20 
  per 
  cent. 
  It 
  is 
  gratifying 
  to 
  know 
  that 
  it 
  is 
  within 
  

   about 
  20 
  per 
  cent, 
  of 
  the 
  values 
  of 
  the 
  charge 
  carried 
  by 
  ions 
  

   from 
  other 
  sources. 
  However, 
  it 
  must 
  be 
  recognized 
  that 
  

   our 
  observations 
  do 
  not 
  furnish 
  an 
  absolute 
  measurement 
  of 
  

   the 
  charge, 
  because 
  in 
  the 
  determination 
  of 
  the 
  kinetic 
  

   energy, 
  the 
  value 
  of 
  ne 
  was 
  assumed 
  to 
  be 
  of 
  the 
  same 
  value 
  

   as 
  in 
  electrolysis. 
  On 
  the 
  other 
  hand, 
  if 
  our 
  interpretation 
  

   of 
  the 
  kinetic 
  energy 
  of 
  the 
  thermions 
  is 
  accepted, 
  then 
  the 
  

   value 
  of 
  the 
  charge 
  must 
  also 
  be 
  accepted. 
  

  

  The 
  Mature 
  of 
  the 
  Positive 
  Thermions, 
  

  

  The 
  evidence 
  furnished 
  in 
  this 
  paper 
  does 
  not 
  give 
  us 
  any 
  

   proof 
  as 
  to 
  the 
  nature 
  of 
  the 
  positive 
  ions. 
  However, 
  we 
  

   may 
  point 
  out 
  certain 
  conclusions 
  which 
  are 
  consistent 
  with 
  

   the 
  results. 
  The 
  facts 
  that 
  the 
  kinetic 
  energy 
  and 
  the 
  ratio 
  

  

  of 
  — 
  , 
  as 
  measured 
  by 
  J. 
  J. 
  Thomson 
  *, 
  0. 
  W. 
  Richardson 
  t, 
  

  

  m' 
  -^ 
  ' 
  

  

  and 
  Mr. 
  E. 
  R. 
  Hulbirt 
  t, 
  are 
  approximately 
  the 
  same, 
  lead 
  

   us 
  to 
  infer 
  that 
  the 
  positive 
  thermions 
  are 
  essentially 
  of 
  the 
  

   same 
  structure, 
  if 
  not 
  identically 
  the 
  same. 
  In 
  addition 
  it 
  

   is 
  seen 
  from 
  the 
  summary 
  table 
  that 
  for 
  the 
  same 
  area 
  of 
  

   emitting 
  surface 
  and 
  at 
  the 
  same 
  temperature, 
  the 
  thermionic 
  

   current 
  has 
  about 
  the 
  same 
  value 
  in 
  all 
  cases 
  in 
  a 
  freshly 
  

   heated 
  surface. 
  The 
  first 
  mentioned 
  facts 
  may 
  be 
  in 
  agree- 
  

   ment 
  with 
  the 
  view 
  suggested 
  by 
  Prof. 
  0. 
  W. 
  Richardson, 
  

   that 
  the 
  positive 
  thermions 
  may 
  be 
  some 
  impurity 
  such 
  as 
  

   the 
  sodium 
  atom. 
  However, 
  it 
  does 
  seem 
  a 
  little 
  unlikely 
  

   that 
  such 
  an 
  impurity 
  in 
  all 
  matter 
  should 
  occur 
  in 
  about 
  

   the 
  same 
  quantity 
  in 
  all 
  metals. 
  

  

  The 
  fact 
  that 
  the 
  thermionic 
  current 
  decays 
  with 
  heating 
  

   in 
  all 
  the 
  elements 
  studied 
  is 
  added 
  evidence 
  against 
  the 
  view 
  

   that 
  the 
  positive 
  thermions 
  are 
  not 
  positive 
  electrons 
  essential 
  

   to 
  the 
  structure 
  of 
  the 
  atom. 
  Probably 
  the 
  strongest 
  evidence 
  

   heretofore 
  proposed 
  against 
  such 
  a 
  view 
  is 
  in 
  the 
  observations 
  

  

  * 
  * 
  Conduction 
  of 
  Electricity 
  througli 
  Gases,' 
  2nd 
  ed. 
  p. 
  148. 
  

   t 
  Phil. 
  Mag. 
  Nov. 
  1908, 
  p. 
  740. 
  

   X 
  Paper 
  not 
  yet 
  published. 
  

  

  