﻿Energy 
  of 
  the 
  Ions 
  emitted 
  by 
  Hot 
  Bodies. 
  691 
  

  

  to 
  the 
  same 
  maximum 
  by 
  multiplying 
  all 
  tlie 
  terms 
  in 
  it 
  by 
  a 
  

   common 
  factor, 
  then 
  all 
  the 
  points 
  of 
  all 
  the 
  different 
  series 
  

   should 
  lie 
  on 
  a 
  common 
  curve 
  which 
  should 
  be 
  identical 
  with 
  

   that 
  predicted 
  theoretically. 
  To 
  test 
  this 
  the 
  results 
  of 
  the 
  

   experiments 
  recorded 
  in 
  the 
  foregoing 
  table 
  have 
  been 
  plotted 
  

   in 
  fig. 
  3. 
  The 
  method 
  adopted 
  has 
  been 
  to 
  first 
  plot 
  the 
  

   numbers 
  in 
  column 
  4 
  against 
  those 
  in 
  column 
  1. 
  The 
  points 
  

   X 
  thus 
  obtained 
  are 
  found 
  to 
  lie 
  on 
  a 
  smooth 
  curve 
  with 
  a 
  

   maximum 
  ordinate 
  of 
  l*3i) 
  at 
  204 
  turns. 
  The 
  theoretical 
  

   curve 
  

  

  which 
  passed 
  through 
  this 
  point 
  was 
  then 
  constructed, 
  the 
  

   distance 
  z 
  during 
  the 
  experiments 
  being 
  0"4 
  cm. 
  This 
  is 
  the 
  

   continuous 
  curve 
  shown 
  in 
  fig. 
  3. 
  In 
  addition 
  to 
  the 
  set 
  of 
  

   observations 
  corresponding 
  to 
  the 
  current 
  direct, 
  those 
  with 
  

   the 
  current 
  reversed 
  are 
  also 
  shown 
  in 
  fig. 
  3. 
  The 
  values 
  in 
  

   column 
  6, 
  however, 
  have 
  not 
  been 
  taken 
  as 
  they 
  stand, 
  but 
  

   have 
  all 
  been 
  multiplied 
  by 
  a 
  common 
  factor 
  so 
  as 
  to 
  reduce 
  

   the 
  maximum 
  to 
  1*39. 
  They 
  can 
  thus 
  be 
  compared 
  with 
  the 
  

   current 
  direct 
  at 
  the 
  same 
  time. 
  They 
  are 
  shown 
  by 
  the 
  

   points 
  marked 
  thus 
  O 
  in 
  fig. 
  3. 
  The 
  series 
  of 
  points 
  marked 
  

   thus 
  A 
  correspond 
  to 
  another 
  set 
  of 
  observations 
  also 
  with 
  

   the 
  current 
  reversed, 
  in 
  which 
  a 
  somewhat 
  higher 
  temperature 
  

   and 
  larger 
  capacities 
  were 
  used 
  than 
  in 
  the 
  preceding. 
  These 
  

   again 
  have 
  all 
  been 
  multiplied 
  by 
  an 
  appropriate 
  factor 
  to 
  

   bring 
  the 
  maximum 
  to 
  the 
  value 
  1*39 
  corresponding 
  to 
  the 
  

   first 
  set 
  of 
  numbers. 
  

  

  The 
  exact 
  data 
  corresponding 
  to 
  fig. 
  3 
  are 
  : 
  — 
  

  

  (1) 
  Full 
  curve 
  represents 
  the 
  theoretical 
  curve 
  

  

  (2) 
  X 
  Current 
  Direct. 
  Temperature 
  = 
  1034° 
  C. 
  Cai)a- 
  

  

  cities 
  used 
  ='3 
  microfarad 
  and 
  "01 
  microfarad. 
  

   Mean 
  deflexion 
  for 
  plates 
  and 
  slit 
  93 
  divs. 
  in 
  

   30 
  sees. 
  

  

  (3) 
  ©Current 
  Reversed. 
  Temperature 
  =1069° 
  C. 
  Ca- 
  

  

  pacities 
  -3 
  and 
  '01. 
  Mean 
  deflexion 
  53 
  divs. 
  in 
  

   30 
  sees. 
  

  

  (4) 
  A 
  Current 
  Reversed. 
  Temperature 
  =1098^ 
  C. 
  Ca- 
  

  

  pacities 
  1 
  microfarad 
  and 
  '04 
  microfarad. 
  Mean 
  

   deflexion 
  for 
  slit 
  and 
  plates 
  68 
  divs. 
  in 
  30 
  sees. 
  

   The 
  mean 
  deflexions 
  have 
  been 
  given 
  so 
  that 
  an 
  estimate 
  

  

  may 
  be 
  made 
  of 
  the 
  total 
  thermionic 
  current 
  to 
  the 
  slit 
  and 
  

  

  the 
  plates. 
  

  

  