﻿668 
  Prof. 
  S. 
  B. 
  McLaren 
  on 
  a 
  

  

  surface, 
  and 
  the 
  tangential 
  component 
  of 
  E' 
  is 
  zero. 
  Hence 
  

   in 
  (84) 
  

  

  E'rfr= 
  0, 
  

   and 
  therefore 
  

  

  jjHaB 
  

  

  is 
  a 
  constant. 
  Thus 
  the 
  magnetic 
  induction 
  through 
  any 
  

   aperture 
  is 
  constant. 
  

  

  It 
  is 
  evidently 
  arbitrary 
  to 
  give 
  always 
  a 
  negative 
  sign 
  

   (that 
  of 
  the 
  electron) 
  to 
  the 
  charge 
  on 
  the 
  simply 
  con- 
  

   nected 
  material 
  surface, 
  and 
  a 
  positive 
  sign 
  to 
  the 
  charge 
  of 
  

   a 
  magneton. 
  But 
  any 
  theory 
  whatever 
  must 
  be 
  in 
  this 
  sense 
  

   arbitrary. 
  What 
  is 
  important 
  is 
  to 
  notice 
  that 
  our 
  distinction 
  

   between 
  positive 
  and 
  negative 
  charges 
  suggests 
  a 
  reason 
  for 
  

   the 
  difference 
  of 
  mass. 
  

  

  Taking 
  the 
  boundary 
  condition 
  (69) 
  

  

  i 
  (W-W)+mJ= 
  V 
  m 
  -V 
  a 
  , 
  

  

  07T 
  

  

  it 
  is 
  evident 
  that 
  written 
  in 
  the 
  form 
  

  

  i 
  W 
  = 
  ^W-mJ+ 
  V 
  m 
  - 
  V 
  a 
  

  

  07T 
  07T 
  

  

  it 
  suggests 
  that 
  E 
  2 
  is 
  larger 
  in 
  the 
  magneton 
  than 
  in 
  the 
  

   electron. 
  So 
  too, 
  therefore, 
  may 
  be 
  the 
  electromagnetic 
  

   mass. 
  

  

  § 
  9. 
  The 
  Electromagnetic 
  Equations 
  in 
  

   Moving 
  ^Ether. 
  

  

  I 
  am 
  aware 
  that 
  such 
  a 
  theory 
  of 
  the 
  aether 
  as 
  is 
  main- 
  

   tained 
  in 
  this 
  paper 
  will 
  appear 
  quite 
  unsatisfactory 
  to 
  those 
  

   who 
  are 
  unwilling 
  to 
  accept 
  a 
  four-dimensional 
  universe 
  as 
  

   the 
  physical 
  reality 
  underlying 
  our 
  changing 
  experience. 
  

   It 
  will 
  appear 
  to 
  them 
  inexplicable 
  that 
  the 
  motion 
  of 
  aether 
  

   should 
  produce 
  no 
  result 
  on 
  the 
  motion 
  of 
  light. 
  I 
  shall 
  now 
  

   show 
  that 
  the 
  four-dimensional 
  theory 
  is 
  capable 
  of 
  a 
  rational 
  

   expression 
  in 
  terms 
  of 
  ordinary 
  space 
  and 
  time 
  concepts. 
  

  

  What 
  is 
  required 
  is 
  some 
  form 
  of 
  the 
  electromagnetic 
  

   equations 
  which 
  describe 
  the 
  course 
  of 
  events 
  at 
  points 
  

   moving 
  with 
  the 
  moving 
  aether. 
  The 
  time 
  variable 
  must 
  be 
  

   in 
  fact 
  local 
  to 
  points 
  of 
  the 
  aether. 
  Such 
  a 
  time 
  variable 
  is 
  

   at 
  once 
  given 
  by 
  the 
  Newtonian 
  potential 
  itself. 
  I 
  write 
  

  

  ta=~ 
  J/C 
  2 
  , 
  (85) 
  

  

  then 
  dt 
  a 
  = 
  p(dt- 
  udr/c 
  2 
  ) 
  . 
  By 
  (40) 
  . 
  

  

  