﻿Phil. 
  Mag, 
  Ser. 
  C. 
  Vol, 
  18, 
  PI. 
  I. 
  

  

  Fio. 
  3.— 
  Curves 
  for 
  rotation 
  on 
  transmission 
  tlirougli 
  Flnovite, 
  

   ."liowing 
  effect 
  of 
  using 
  bigli 
  and 
  low 
  dispersion. 
  

  

  

  

  ) 
  

  

  ~T, 
  

  

  

  — 
  

  

  

  ~ 
  

  

  

  — 
  

  

  n 
  

  

  

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  , 
  

  

  

  

  

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  „ 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  Fig. 
  4.— 
  Curves 
  for 
  rotation 
  on 
  reflexion 
  from 
  steel, 
  sliowin" 
  

   measurements 
  with 
  high 
  and 
  low 
  dispei-sion 
  arrangements." 
  

  

  

  r 
  

  

  

  

  

  

  

  

  

  

  

  

  n 
  

  

  n 
  

  

  r 
  

  

  r- 
  

  

  ~ 
  

  

  ^ 
  

  

  

  

  

  

  

  

  

  

  

  

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  - 
  

  

  ^4A- 
  

  

  

  — 
  

  

  

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  n 
  

  

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  - 
  

  

  - 
  

  

  jrrs 
  

  

  

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  ~ 
  

  

  

  

  ~ 
  

  

  ■y 
  

  

  

  

  

  ly^ 
  

  

  

  

  

  1 
  

  

  5- 
  

  

  

  

  

  2 
  0, 
  

  

  

  

  

  

  Fio. 
  7.— 
  

  

  Cur 
  

  

  V6S 
  

  

  for 
  film 
  1 
  

  

  7, 
  of 
  30 
  /.^thickness. 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

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  -„- 
  

  

  z^ 
  

  

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  — 
  

  

  

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  ix 
  

  

  

  

  

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  i^ 
  

  

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  o% 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  5 
  " 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

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  . 
  

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  1 
  

  

  sr 
  

  

  

  

  

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  °r 
  

  

  

  

  Wqvelength. 
  

  

  Fig. 
  11.— 
  Curves 
  for 
  partially 
  oxidized 
  film 
  7. 
  Transmission 
  curve 
  

   has 
  been 
  conected 
  for 
  the 
  rotation 
  of 
  the 
  glass. 
  On 
  the 
  

   reflexion 
  curve, 
  points 
  plotted 
  as 
  triang-les 
  were 
  deter- 
  

   mined 
  with 
  the 
  rear 
  glass 
  surface 
  covered 
  with 
  Canada 
  

   balsam 
  and 
  lanip-blaolt. 
  

  

  

  

  — 
  

  

  ~ 
  

  

  

  r 
  

  

  "~ 
  

  

  

  ~ 
  

  

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  Fig. 
  8.— 
  Cu 
  

  

  

  for 
  fim 
  2 
  

  

  2, 
  of 
  13 
  ,1/i 
  thick 
  

  

  nes 
  

  

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  • 
  no 
  

  

  

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  "/- 
  

  

  

  

  10 
  

  

  12.— 
  Curves 
  for 
  partially 
  oxidized 
  film 
  14 
  

   curve 
  has 
  been 
  corrected 
  for 
  rotation 
  due 
  

  

  Transm 
  

   to 
  glass. 
  

  

  iss 
  

  

  on 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

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  -^ 
  

  

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  1.} 
  

  

  Fio. 
  0.- 
  

  

  Curves 
  for 
  til 
  

  

  n 
  

  

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  if 
  r,s,>,. 
  thiol 
  

  

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  Fig. 
  9.— 
  Curves 
  for 
  film 
  LM, 
  of 
  8 
  ,,,, 
  thicliiios 
  

  

  WQKtknjIh. 
  

  

  Fill. 
  10. 
  

  

  

  Fio. 
  13.— 
  Curves 
  for 
  rotation 
  on 
  reflexion 
  and 
  for 
  reflecting 
  

   power 
  of 
  opaque, 
  partially 
  oxidized, 
  film 
  29. 
  The 
  

   reflecting 
  power 
  curve 
  of 
  pure 
  iron 
  film 
  lo 
  is 
  shown 
  

   for 
  comparison. 
  

  

  n 
  — 
  '■ 
  _ 
  

  

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  ~ 
  .5 
  

  

  r 
  

  

  

  

  

  

  

  

  

  

  

  

  

  M- 
  

  

  

  Fio. 
  14.— 
  Curviw 
  Bhowino; 
  the 
  rotAtion 
  on 
  reflexion 
  from 
  Hui 
  

   Kla»«.iron 
  suiliicea 
  of 
  fllm« 
  IC, 
  17, 
  22. 
  

  

  

  