﻿Rowland 
  — 
  The 
  Highest 
  Aim 
  of 
  the 
  Physicist. 
  407 
  

  

  wliere 
  molecules 
  are 
  concerned 
  and 
  when 
  the 
  period 
  of 
  vibra- 
  

   tion 
  is 
  immensely 
  great. 
  Indeed 
  the 
  experiment 
  on 
  the 
  mag- 
  

   netic 
  action 
  of 
  electric 
  convection 
  shows 
  the 
  same 
  thing. 
  By 
  

   electrifying 
  a 
  disc 
  in 
  motion 
  it 
  appears 
  as 
  if 
  the 
  disc 
  holds 
  fast 
  

   to 
  the 
  ether 
  and 
  drags 
  it 
  with 
  it, 
  thus 
  setting 
  up 
  the 
  peculiar 
  

   etherial 
  motion 
  known 
  as 
  magnetism. 
  

  

  Have 
  we 
  not 
  another 
  case 
  of 
  a 
  similar 
  nature 
  when 
  a 
  huge 
  

   gravitational 
  mass 
  like 
  that 
  of 
  the 
  earth 
  revolves 
  on 
  its 
  axis 
  ? 
  

   Has 
  not 
  matter 
  a 
  feeble 
  hold 
  on 
  the 
  ether 
  sufficient 
  to 
  produce 
  

   the 
  earth's 
  magnetism 
  ? 
  

  

  But 
  the 
  experiment 
  of 
  Lodge 
  to 
  detect 
  such 
  an 
  action 
  

   apparently 
  showed 
  that 
  it 
  must 
  be 
  very 
  feeble. 
  Might 
  not 
  his 
  

   experiment 
  have 
  succeeded 
  had 
  he 
  used 
  an 
  electrified 
  revolv- 
  

   ing 
  disc? 
  

  

  To 
  detect 
  something 
  dependent 
  on 
  the 
  relative 
  motion 
  of 
  

   the 
  ether 
  and 
  matter 
  has 
  been 
  and 
  is 
  the 
  great 
  desire 
  of 
  phys- 
  

   icists. 
  But 
  we 
  always 
  find 
  that, 
  with 
  one 
  possible 
  exception, 
  

   there 
  is 
  always 
  some 
  compensating 
  feature 
  which 
  renders 
  our 
  

   efforts 
  useless. 
  This 
  one 
  experiment 
  is 
  the 
  aberration 
  of 
  light, 
  

   but 
  even 
  here 
  Stokes 
  has 
  shown 
  that 
  it 
  may 
  be 
  explained 
  in 
  

   either 
  of 
  two 
  ways 
  : 
  first, 
  that 
  the 
  earth 
  moves 
  through 
  the 
  

   ether 
  of 
  space 
  without 
  disturbing 
  it, 
  and 
  second, 
  if 
  it 
  carries 
  the 
  

   ether 
  with 
  it 
  by 
  a 
  kind 
  of 
  motion 
  called 
  irrotational. 
  Even 
  

   here, 
  however, 
  the 
  amount 
  of 
  action 
  probably 
  depends 
  upon 
  

   relative 
  motion 
  of 
  the 
  luminous 
  source 
  to 
  the 
  recipient 
  tele- 
  

   scope. 
  

  

  So 
  the 
  principle 
  of 
  Doppler 
  depends 
  also 
  on 
  this 
  relative 
  

   motion 
  and 
  is 
  independent 
  of 
  the 
  ether. 
  

  

  The 
  result 
  of 
  the 
  experiments 
  of 
  Foucault 
  on 
  the 
  passage 
  of 
  

   light 
  through 
  moving 
  water 
  can 
  no 
  longer 
  be 
  interpreted 
  as 
  

   due 
  to 
  the 
  partial 
  movement 
  of 
  the 
  ether 
  with 
  the 
  moving- 
  

   water, 
  an 
  inference 
  due 
  to 
  imperfect 
  theory 
  alone. 
  The 
  

   experiment 
  of 
  Lodge, 
  who 
  attempted 
  to 
  set 
  the 
  ether 
  in 
  motion 
  

   by 
  a 
  rapidly 
  rotating 
  disc, 
  showed 
  no 
  such 
  result. 
  

  

  The 
  experiment 
  of 
  Michelson 
  to 
  detect 
  the 
  etherial 
  wind, 
  

   although 
  carried 
  to 
  the 
  extreme 
  of 
  accuracy, 
  also 
  failed 
  to 
  

   detect 
  any 
  relative 
  motion 
  of 
  the 
  matter 
  and 
  the 
  ether. 
  

  

  But 
  matter 
  with 
  an 
  electrical 
  charge 
  holds 
  fast 
  to 
  the 
  ether 
  

   and 
  moves 
  it 
  in 
  the 
  manner 
  required 
  for 
  magnetic 
  action. 
  

  

  When 
  electrified 
  bodies 
  move 
  together 
  through 
  space 
  or 
  

   with 
  reference 
  to 
  each 
  other 
  we 
  can 
  only 
  follow 
  their 
  mutual 
  

   actions 
  through 
  very 
  slow 
  and 
  uniform 
  velocities. 
  When 
  they 
  

   move 
  with 
  velocities 
  comparable 
  with 
  that 
  of 
  light, 
  equal 
  to 
  it 
  

   or 
  even 
  beyond 
  it, 
  we 
  calculate 
  their 
  mutual 
  actions 
  or 
  action 
  

   on 
  the 
  ether 
  only 
  by 
  the 
  light 
  of 
  our 
  imagination 
  unguided 
  by 
  

   experiment. 
  The 
  conclusions 
  of 
  J. 
  J. 
  Thomson, 
  Heaviside 
  

   and 
  Hertz 
  are 
  all 
  results 
  of 
  the 
  imagination 
  and 
  they 
  all 
  rest 
  

  

  