﻿CJiarr/e 
  of 
  the 
  Ions 
  emitted 
  by 
  Hot 
  Bodies 
  

  

  759 
  

  

  considerable. 
  The 
  general 
  character 
  of 
  the 
  discrepancies 
  

   was 
  such 
  as 
  might 
  arise 
  if 
  the 
  orientation 
  of 
  the 
  platinum 
  

   strip 
  was 
  subject 
  to 
  slight 
  changes 
  produced 
  by 
  alternate 
  

   heating 
  and 
  cooling. 
  It 
  seems 
  probable 
  that 
  some 
  such 
  

   effect 
  as 
  this 
  was 
  the 
  worst 
  source 
  of 
  error 
  to 
  which 
  the 
  

   measurements 
  were 
  subject. 
  

  

  All 
  the 
  measurements 
  of 
  e/m 
  for 
  the 
  positive 
  ions 
  from 
  

   hot 
  platinum 
  which 
  arrived 
  at 
  a 
  satisfactory 
  termination 
  are 
  

   represented 
  in 
  the 
  following 
  table. 
  The 
  first 
  was 
  that 
  

   already 
  described 
  as 
  obtained 
  by 
  the 
  zero 
  deflexion 
  method 
  ; 
  

   the 
  others 
  were 
  all 
  obtained 
  by 
  the 
  maximum 
  method. 
  The 
  

   values 
  of 
  the 
  ratio 
  m/B. 
  of 
  the 
  mass 
  of 
  the 
  ions 
  to 
  that 
  of 
  an 
  

   atom 
  of 
  hydrogen, 
  on 
  the 
  assumption 
  that 
  both 
  carry 
  identical 
  

   charges, 
  is 
  also 
  given. 
  

  

  - 
  (cm.). 
  

  

  H 
  (lines 
  

   per 
  cm.-). 
  

  

  V 
  (volts). 
  

  

  x. 
  

  

  (1 
  = 
  -0635 
  cm.) 
  

  

  e/m 
  (EM. 
  

   units). 
  

  

  m/H. 
  

  

  •688 
  

  

  1200 
  

  

  55 
  

  

  1-00 
  

  

  310 
  

  

  31-2 
  

  

  •6165 
  

  

  4630 
  

  

  300 
  

  

  1-25 
  

  

  276 
  

  

  35-2 
  

  

  •640 
  

  

  4630 
  

  

  341 
  

  

  1-42 
  

  

  357 
  

  

  27-2 
  

  

  •5:34 
  

  

  4670 
  

  

  78 
  

  

  1-85 
  

  

  275 
  

  

  35-2 
  

  

  •634 
  

  

  4670 
  

  

  78-1 
  

  

  171 
  

  

  235 
  

  

  41-2 
  

  

  •534 
  

  

  4670 
  

  

  324 
  

  

  •97 
  

  

  317 
  

  

  306 
  

  

  •534 
  

  

  3000 
  

  

  78-5 
  

  

  1-04 
  

  

  211 
  

  

  45-8 
  

  

  •534 
  

  

  3000 
  

  

  783 
  

  

  •97 
  

  

  184 
  

  

  526 
  

  

  

  Mean 
  values 
  e/i 
  

  

  »=271, 
  r/ifH. 
  = 
  c 
  

  

  >7'4 
  

  

  

  The 
  shape 
  of 
  the 
  distribution 
  curves 
  obtained 
  in 
  the 
  last 
  

   experiment, 
  and 
  to 
  a 
  smaller 
  extent 
  in 
  the 
  one 
  which 
  preceded 
  

   it, 
  indicated 
  that 
  for 
  some 
  reason 
  or 
  another 
  the 
  mean 
  kinetic 
  

   energy 
  of 
  the 
  ions 
  had 
  diminished 
  very 
  considerably 
  (by 
  a 
  

   factor 
  of 
  about 
  four 
  in 
  fact). 
  This 
  diminution 
  may 
  have 
  

   been 
  accompanied 
  by 
  a 
  real 
  change 
  in 
  the 
  nature 
  of 
  the 
  ions, 
  

   so 
  that 
  the 
  last 
  two 
  comparatively 
  high 
  values 
  of 
  m/'H 
  may 
  

   be 
  real 
  and 
  not 
  due 
  to 
  experimental 
  error. 
  Leaving 
  them 
  

   out 
  of 
  account, 
  the 
  means 
  of 
  the 
  first 
  six 
  determinations 
  are 
  

   e/m 
  = 
  29o 
  and 
  ?n/H 
  = 
  33'4. 
  The 
  greatest 
  disagreement 
  of 
  

   any 
  observation 
  from 
  this 
  value 
  is 
  a 
  little 
  over 
  20 
  per 
  cent., 
  

   if 
  we 
  regard 
  the 
  last 
  two 
  measurements 
  as 
  exceptional. 
  

  

  