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  Trowbridge 
  and 
  Richards 
  — 
  Multiple 
  Spectra 
  of 
  Gases. 
  

  

  As 
  Crookes 
  and 
  others 
  have 
  already 
  pointed 
  out, 
  since 
  many 
  

   gases 
  yield 
  different 
  spectra 
  under 
  the 
  influence 
  of 
  varying 
  

   electrical 
  conditions, 
  it 
  is 
  evident 
  that 
  the 
  fact 
  of 
  the 
  existence 
  

   of 
  two 
  well-marked 
  spectra 
  of 
  argon 
  gives 
  not 
  the 
  slightest 
  

   presumption 
  in 
  favor 
  of 
  the 
  hypothesis 
  that 
  the 
  new 
  gas 
  is 
  a 
  

   mixture. 
  In 
  order 
  to 
  discover 
  if 
  argon 
  possesses 
  a 
  dual 
  nature, 
  

   the 
  gas 
  must 
  be 
  split 
  up 
  in 
  such 
  a 
  way 
  that 
  its 
  components 
  

   give 
  different 
  spectra 
  under 
  like 
  electrical 
  conditions 
  ; 
  then 
  

   alone 
  would 
  the 
  evidence 
  of 
  the 
  spectroscope 
  be 
  of 
  weight 
  in 
  

   proving 
  the 
  dissimilarity 
  of 
  the 
  several 
  parts. 
  

  

  The 
  results 
  of 
  this 
  work 
  are 
  thus 
  far 
  only 
  those 
  which 
  were 
  

   to 
  have 
  been 
  expected 
  from 
  a 
  high 
  tension 
  galvanic 
  battery, 
  

   reasoning 
  from 
  the 
  work 
  of 
  other 
  investigators 
  with 
  the 
  Toep- 
  

   ler-Holtz 
  machine. 
  The 
  battery, 
  however, 
  gives 
  a 
  current 
  so 
  

   admirably 
  constant 
  and 
  so 
  easily 
  regulated 
  as 
  to 
  its 
  tension, 
  

   that 
  we 
  hope 
  to 
  be 
  able 
  to 
  use 
  it 
  as 
  a 
  means 
  of 
  determining 
  

   whether 
  the 
  oscillatory 
  discharge 
  produces 
  its 
  effect 
  simply 
  by 
  

   increasing 
  the 
  temperature, 
  or 
  because 
  of 
  some 
  inherent 
  prop- 
  

   erty 
  in 
  the 
  manner 
  of 
  the 
  discharge. 
  

  

  It 
  is 
  our 
  intention 
  to 
  extend 
  the 
  investigation 
  by 
  the 
  sys- 
  

   tematic 
  photographic 
  study 
  of 
  the 
  action 
  of 
  the 
  varying 
  dis- 
  

   charge 
  upon 
  all 
  the 
  elementary 
  gases 
  in 
  the 
  purest 
  condition, 
  

   as 
  well 
  as 
  upon 
  mixtures 
  under 
  widely 
  varying 
  conditions 
  of 
  

   temperature 
  and 
  pressure. 
  

  

  Harvard 
  University. 
  

  

  