﻿THE 
  

  

  LONDON, 
  EDINBURGH 
  and 
  DUBLIN 
  

  

  PHILOSOPHICAL 
  MAGAZINE 
  

  

  AND 
  

  

  JOURNAL 
  OF 
  SC1W 
  

  

  [SIXTH 
  SERIES.] 
  

  

  OCTOBER 
  1913. 
  

  

  

  

  

  

  <)) 
  

  

  XLV. 
  The 
  Photoelectric 
  Effect.— 
  11. 
  By 
  Karl 
  T,- 
  Golii^N 
  

   and 
  0. 
  W. 
  Richardson, 
  Princeton 
  University 
  *7 
  

  

  Introduction. 
  

  

  f 
  jPHERE 
  are 
  two 
  lines 
  of 
  experimental 
  investigation 
  which 
  

   * 
  have 
  been 
  followed 
  in 
  the 
  search 
  for 
  the 
  ultimate 
  

   explanation 
  of 
  the 
  photoelectric 
  effect 
  from 
  metals. 
  Most 
  of 
  

   the 
  work 
  in 
  this 
  subject 
  has 
  had 
  to 
  do 
  with 
  the 
  velocities 
  

   of 
  the 
  emitted 
  electrons 
  and 
  the. 
  relation 
  of 
  these 
  velocities 
  

   to 
  the 
  nature 
  of 
  the 
  emitting 
  metal 
  and 
  the 
  frequency 
  and. 
  

   intensity 
  of 
  the 
  incident 
  light. 
  Numerous 
  experimenters 
  

   have 
  shown 
  that 
  the 
  velocities 
  of 
  the 
  electrons 
  are 
  independent 
  

   of 
  the 
  intensity 
  of 
  the 
  incident 
  light, 
  and 
  are 
  nearly, 
  if 
  not 
  

   entirely, 
  independent 
  of 
  the 
  photoelectric 
  fatigue, 
  except 
  in 
  

   so 
  far 
  as 
  this 
  fatigue 
  alters 
  the 
  intrinsic 
  potential 
  of 
  the 
  metal 
  f, 
  

   and 
  therefore 
  alters 
  the 
  amount 
  of 
  energy 
  lost 
  by 
  the 
  electrons 
  

   in 
  escaping. 
  It 
  has 
  therefore 
  been 
  possible 
  to 
  investigate 
  the 
  

   relation 
  between 
  velocity 
  and 
  frequency 
  without 
  having 
  to 
  

   take 
  special 
  means 
  of 
  allowing 
  for 
  these 
  two 
  factors. 
  To 
  

   this 
  extent 
  the 
  investigation 
  of 
  photoelectron 
  velocities 
  is 
  free 
  

   from 
  complications 
  which 
  are 
  troublesome 
  when 
  the 
  number 
  

   of 
  emitted 
  electrons 
  instead 
  of 
  their 
  velocities 
  is 
  being 
  studied. 
  

   This 
  line 
  of 
  investigation 
  has 
  therefore 
  received 
  the 
  most 
  

   attention. 
  

  

  * 
  Communicated 
  by 
  the 
  Authors. 
  

  

  t 
  K. 
  T. 
  Compton, 
  Phil. 
  Mag. 
  vol. 
  xxiii. 
  p. 
  579 
  (1912). 
  

  

  Phil. 
  Mag. 
  S. 
  6. 
  Vol. 
  26. 
  No. 
  154. 
  Oct. 
  1913. 
  2 
  P 
  

  

  