﻿58 
  

  

  Mr. 
  W. 
  G. 
  Hormell 
  on 
  the 
  

  

  The 
  same 
  quantity 
  may 
  be 
  secured 
  by 
  subtracting 
  the 
  first 
  

   reading 
  from 
  the 
  third 
  and 
  the 
  second 
  from 
  the 
  fourth. 
  

  

  Summary 
  of 
  the 
  Line 
  Constants. 
  

   (1) 
  58-94-58-14 
  = 
  '80 
  cm. 
  = 
  tube 
  effect. 
  

   58-14 
  + 
  -3 
  

   2 
  

  

  (2) 
  

  

  29*22 
  cm. 
  = 
  1/2 
  tube 
  wave. 
  

  

  (3) 
  58*94 
  + 
  -3 
  + 
  *80 
  + 
  1*80 
  = 
  61*84 
  cm. 
  = 
  wave-length 
  in 
  air. 
  

   (4)89-49-27-80... 
  =61*69 
  cm. 
  = 
  

   (5)120-61-58-94... 
  =61*67 
  cm. 
  = 
  „ 
  „ 
  

  

  61*73 
  cm.= 
  average 
  wave- 
  

   length 
  in 
  air. 
  

  

  It 
  will 
  be 
  seen 
  that 
  the 
  wave-length 
  in 
  air 
  determined 
  by 
  

   the 
  first 
  method 
  (3) 
  is 
  very 
  approximately 
  the 
  same 
  as 
  that 
  

   secured 
  by 
  the 
  second 
  method 
  (4) 
  and 
  (5). 
  

  

  (b) 
  Determination 
  of 
  the 
  Dependence 
  of 
  the 
  Wave-length 
  

   upon 
  the 
  Distance 
  between 
  the 
  Primary 
  and 
  the 
  

   Secondary 
  Coils. 
  

   In 
  this 
  experiment 
  the 
  coils 
  were 
  5 
  cm. 
  in 
  diameter. 
  The 
  

   primary 
  semicircles 
  were 
  made 
  of 
  3 
  mm. 
  wire, 
  and 
  had 
  dis- 
  

   charging 
  balls 
  5 
  mm. 
  in 
  diameter. 
  The 
  pitch 
  of 
  the 
  screw 
  

   controlling 
  the 
  primary 
  was 
  1*27 
  mm. 
  The 
  primary 
  was 
  

   removed 
  and 
  replaced 
  a 
  number 
  of 
  times 
  in 
  order 
  to 
  test 
  the 
  

   accuracy 
  with 
  which 
  the 
  relative 
  positions 
  of 
  the 
  coils 
  could 
  

   be 
  reproduced. 
  In 
  all 
  the 
  cases 
  the 
  agreement 
  of 
  the 
  wave- 
  

   lengths 
  was 
  very 
  satisfactory. 
  

  

  Table 
  II. 
  

  

  Distance 
  between 
  

   centres 
  of 
  coils. 
  

  

  Wave-length. 
  

  

  2-84 
  millim. 
  

  

  89-80 
  millim. 
  

  

  3-15 
  „ 
  

  

  87-25 
  „ 
  

  

  3-46 
  „ 
  

  

  84-80 
  „ 
  

  

  3'77 
  „ 
  

  

  80-20 
  „ 
  

  

  4*08 
  „ 
  

  

  76-10 
  „ 
  

  

  4-39 
  „ 
  

  

  73-05 
  „ 
  

  

  4-69 
  „ 
  

  

  71-15 
  „ 
  

  

  