﻿34:2 
  Trowbridge 
  and 
  Richards 
  — 
  Temperature, 
  etc. 
  

  

  Assuming, 
  then, 
  that 
  the 
  red 
  spectrum 
  of 
  hydrogen 
  is 
  due 
  

   to 
  the 
  sudden 
  occurrence 
  of 
  the 
  reaction 
  

  

  H=H-f-H 
  

  

  it 
  is 
  very 
  interesting 
  to 
  note 
  that 
  our 
  results 
  agree 
  with 
  the 
  

   necessary 
  deductions 
  from 
  the 
  law 
  of 
  mass 
  action 
  as 
  applied 
  to 
  

   this 
  case. 
  If 
  the 
  reaction 
  is 
  supposed 
  to 
  take 
  place 
  isotherm- 
  

   ally 
  at 
  a 
  very 
  high 
  temperature, 
  it 
  is 
  manifest 
  that 
  the 
  progress 
  

   of 
  the 
  reaction 
  from 
  right 
  to 
  left 
  must 
  increase 
  as 
  the 
  concen- 
  

   tration 
  of 
  the 
  hydrogen 
  — 
  in 
  other 
  words, 
  the 
  tension 
  of 
  gas 
  — 
  

   is 
  diminished. 
  This 
  we 
  find 
  to 
  be 
  the 
  case: 
  the 
  resistance 
  of 
  

   the 
  gas 
  increases 
  and 
  the 
  purity 
  of 
  the 
  " 
  four-line 
  " 
  spectrum 
  

   diminishes 
  as 
  the 
  tension 
  of 
  the 
  gas 
  increases, 
  except 
  when 
  the 
  

   gas 
  is 
  exceedingly 
  rarified. 
  In 
  this 
  last 
  case 
  it 
  is 
  probable 
  that 
  

   the 
  number 
  of 
  atoms 
  present, 
  even 
  if 
  all 
  were 
  free, 
  would 
  be 
  

   insufficient 
  to 
  carry 
  all 
  the 
  current. 
  Hence 
  we 
  should 
  expect 
  

   to 
  find 
  this 
  minimum 
  at 
  a 
  lower 
  pressure 
  when 
  the 
  capacity 
  of 
  

   the 
  condenser 
  employed 
  was 
  less 
  ; 
  but 
  unfortunately 
  the 
  spark 
  

   is 
  too 
  uncertain 
  at 
  these 
  very 
  low 
  temperatures, 
  even 
  with 
  

   twenty 
  thousand 
  volts 
  from 
  the 
  complete 
  battery, 
  to 
  give 
  defi- 
  

   nite 
  results. 
  

  

  Since 
  hydrogen 
  undoubtedly 
  requires 
  a 
  very 
  large 
  amount 
  

   of 
  heat 
  for 
  its 
  dissociation, 
  it 
  follows 
  that 
  when 
  the 
  tempera- 
  

   ture 
  is 
  raised 
  while 
  the 
  pressure 
  is 
  kept 
  constant, 
  more 
  atoms 
  

   should 
  be 
  set 
  free. 
  We 
  find, 
  as 
  a 
  matter 
  of 
  fact, 
  that 
  the 
  

   resistance 
  diminishes 
  as 
  we 
  increase 
  the 
  capacity 
  of 
  the 
  con- 
  

   denser 
  — 
  that 
  is 
  to 
  say, 
  the 
  heat 
  of 
  the 
  discharge. 
  The 
  case 
  is 
  

   exactly 
  analogous 
  to 
  the 
  dissociation 
  of 
  nitric 
  peroxide 
  observed 
  

   by 
  E. 
  and 
  L. 
  Natanson."* 
  

  

  Our 
  work 
  leads 
  one 
  to 
  infer 
  that 
  since 
  a 
  very 
  high 
  tempera- 
  

   ture 
  is 
  needed 
  to 
  produce 
  the 
  " 
  four-line" 
  spectrum 
  of 
  hydro- 
  

   gen, 
  this 
  high 
  temperature 
  must 
  be 
  present 
  wherever 
  this 
  

   spectrum 
  appears; 
  for 
  example, 
  in 
  the 
  solar 
  prominences 
  and 
  

   in 
  many 
  fixed 
  stars. 
  The 
  higher 
  the 
  tension 
  of 
  the 
  gas, 
  the 
  

   higher 
  the 
  temperature 
  required 
  ; 
  hence 
  one 
  must 
  know 
  the 
  

   atmospheric 
  pressures 
  in 
  these 
  heavenly 
  bodies 
  before 
  attempt- 
  

   ing 
  to 
  guess 
  at 
  the 
  actual 
  temperature 
  attained; 
  but 
  there 
  can 
  

   be 
  no 
  doubt 
  that 
  this 
  temperature 
  is 
  in 
  any 
  case 
  far 
  beyond 
  

   the 
  reach 
  of 
  any 
  earthly 
  means 
  except 
  the 
  electric 
  discharge 
  

   which 
  we 
  have 
  been 
  considering. 
  

  

  * 
  Wied. 
  Ann., 
  xxiv, 
  454, 
  and 
  xxvii, 
  606. 
  

   Harvard 
  University, 
  Feb. 
  23d, 
  1897. 
  

  

  