﻿Radiation 
  in 
  a 
  Magnetic 
  Field. 
  355 
  

  

  Fig. 
  5 
  gives 
  the 
  intensity-curves 
  of 
  the 
  corresponding 
  

   spectra, 
  the 
  abscissae 
  being 
  expressed 
  in 
  tenth-metres 
  t« 
  

  

  Folio 
  wins: 
  is 
  a 
  list 
  of 
  the 
  radiations 
  examined 
  and 
  their 
  

   classification 
  : 
  — 
  

  

  Mercury 
  Yellow 
  lines. 
  Type 
  !• 
  

  

  Green 
  line. 
  Type 
  III. 
  

  

  Violet 
  line. 
  Type 
  II. 
  

  

  Cadmium 
  Red 
  line. 
  Type 
  I- 
  

  

  Green 
  line. 
  Type 
  III. 
  

  

  Blue 
  line. 
  Type 
  II. 
  

  

  Zinc 
  Red 
  line. 
  Type 
  T. 
  

  

  Green 
  line. 
  Type 
  III. 
  

  

  Blue 
  line. 
  Type 
  II. 
  

  

  Sodium 
  Yellow 
  lines. 
  Type 
  II. 
  

  

  Thallium 
  Green 
  line. 
  Type 
  II. 
  (doubtful). 
  

  

  Lithium 
  Red 
  line. 
  (Too 
  broad 
  to 
  determine.) 
  

  

  Hydrogen 
  Red 
  and 
  blue 
  lines. 
  (Too 
  broad 
  to 
  determine.) 
  

  

  Helium 
  Yellow 
  and 
  green 
  lines. 
  (Too 
  broad 
  to 
  determine.) 
  

  

  The 
  following 
  table 
  shows 
  that 
  the 
  law 
  A 
  2 
  is 
  only 
  approxi- 
  

   mately 
  true. 
  

  

  In 
  fact, 
  owing 
  to 
  the 
  complexity 
  of 
  the 
  spectra, 
  there 
  is 
  

   considerable 
  latitude 
  in 
  the 
  choice 
  of 
  the 
  distance 
  between 
  

   the 
  outer 
  groups. 
  If 
  this 
  correspond 
  to 
  the 
  brightest 
  com- 
  

   ponents, 
  the 
  law 
  can 
  hardly 
  be 
  said 
  to 
  hold 
  at 
  all 
  ; 
  but 
  if 
  the 
  

   distance 
  be 
  taken 
  between 
  the 
  centres 
  of 
  gravity 
  of 
  the 
  light 
  

   areas, 
  a 
  fair 
  agreement 
  is 
  found. 
  The 
  table 
  gives 
  separation 
  

   in 
  tenth-metres 
  for 
  a 
  field 
  10,000. 
  The 
  lines 
  marked 
  with 
  

   an 
  asterisk 
  are 
  less 
  accurate 
  than 
  the 
  others, 
  on 
  account 
  of 
  

   broadening. 
  

  

  ♦Hydrogen 
  Red 
  048 
  

  

  ♦Lithium 
  Red 
  060 
  

  

  Cadmium 
  Red 
  0-42 
  

  

  Zinc 
  Red 
  042 
  

  

  Mercury 
  . 
  Yellow 
  0-36 
  

  

  ♦Sodium 
  Yellow 
  050 
  

  

  ♦Helium 
  Green 
  0-37 
  

  

  Mercury 
  Green 
  0'4Q 
  

  

  Cadmium 
  Green 
  041 
  

  

  Zinc 
  Green 
  0-40 
  

  

  ♦Thallium 
  Green 
  036 
  

  

  Cadmium 
  Blue 
  040 
  

  

  Zinc 
  Blue 
  033 
  

  

  Mercury 
  Violet 
  033 
  

  

  Taking 
  into 
  account 
  the 
  uncertainty 
  alluded 
  to, 
  the 
  results 
  

   show 
  on 
  the 
  whole 
  a 
  fair 
  agreement, 
  from 
  which 
  it 
  may 
  be 
  

   concluded 
  that 
  the 
  separation 
  is 
  independent 
  of 
  the 
  radiating 
  

   substance 
  and 
  of 
  the 
  colour. 
  

  

  It 
  is 
  possible 
  that 
  some 
  of 
  the 
  resemblances 
  in 
  the 
  preceding 
  

  

  t 
  For 
  this 
  the 
  abscissae 
  of 
  the 
  curve 
  drawn 
  by 
  the 
  analyser 
  are 
  

   multiplied 
  by 
  the 
  square 
  of 
  the 
  wave-length. 
  

  

  