﻿in 
  Iron 
  by 
  Rapidly 
  Oscillating 
  Current-fields. 
  509 
  

  

  The 
  value 
  of 
  L 
  for 
  the 
  coil 
  thus 
  determined 
  was 
  found 
  as 
  

   a 
  mean 
  of 
  9 
  measurements 
  to 
  be 
  79 
  - 
  5 
  + 
  0*4 
  x 
  10 
  6 
  , 
  or 
  nearly 
  

   80 
  x 
  10 
  6 
  cms. 
  The 
  increase 
  of 
  self-induction 
  of 
  the 
  circuit 
  

   due 
  to 
  the 
  introduction 
  of 
  iron 
  into 
  one 
  of 
  the 
  equal 
  solenoids 
  

   was 
  also 
  determined 
  in 
  an 
  exactly 
  similar 
  manner, 
  and 
  for 
  

   different 
  frequencies 
  of 
  oscillation. 
  

  

  7. 
  The 
  full 
  results 
  of 
  a 
  series 
  of 
  observations 
  taken 
  with 
  

   the 
  bundles 
  of 
  iron 
  A, 
  B, 
  (J, 
  and 
  D 
  over 
  the 
  maximum 
  range 
  

   of 
  frequencies 
  obtainable 
  with 
  the 
  coils 
  at 
  our 
  disposal 
  are 
  

   given 
  in 
  Table 
  IV. 
  (p. 
  508). 
  In 
  this 
  table 
  S 
  H 
  represents 
  the 
  

   deflexion 
  due 
  to 
  the 
  '"current" 
  alone, 
  which 
  is 
  proportional 
  

   to 
  the 
  magnetizing 
  force, 
  S 
  M 
  represents 
  the 
  corresponding 
  

   deflexion 
  due 
  to 
  the 
  magnetization 
  induced 
  in 
  the 
  iron, 
  and 
  

   n 
  the 
  number 
  of 
  oscillations 
  per 
  sec. 
  

  

  From 
  these 
  figures 
  the 
  following 
  Table 
  V. 
  was 
  derived, 
  to 
  

   show 
  the 
  alteration 
  of 
  the 
  magnetization 
  with 
  the 
  periodicity 
  

   for 
  various 
  maximum 
  magnetizing 
  forces 
  (H 
  ). 
  The 
  values 
  

  

  Table 
  V 
  

  

  6h. 
  

  

  ir„ 
  

  

  82 
  

   C.G.S. 
  

   units. 
  

  

  66 
  

   C.G.S. 
  

   units. 
  

  

  47 
  

   C.G.S. 
  

   units. 
  

  

  41 
  

  

  C.G.S. 
  

   units. 
  

  

  c 
  M 
  for 
  the 
  bundles 
  

  

  

  A 
  

  

  B 
  

  

  C 
  

  

  69800 
  16 
  

  

  

  21 
  

  

  28-5 
  

  

  

  86200 
  21 
  

  

  

  26-5 
  

  

  34 
  

  

  

  176011 
  25 
  

  

  2(5"5 
  

  

  30-5 
  32 
  

  

  38 
  

  

  40 
  

  

  10300 
  30 
  

  

  

  38 
  

  

  46 
  

  

  

  6200 
  36 
  

  

  

  42 
  

  

  52 
  

  

  

  4200 
  42 
  

  

  

  47 
  

  

  55 
  

  

  

  54 
  

  

  

  56 
  

  

  58 
  

  

  

  . 
  82600 
  1 
  4 
  

  

  M-5 
  

  

  18 
  19 
  

  

  24 
  

  

  25-5 
  

  

  41400 
  18 
  

  

  19 
  

  

  22 
  23*5 
  

  

  265 
  

  

  28 
  

  

  31000 
  19 
  

  

  

  235 
  

  

  30 
  

  

  

  25300 
  20 
  

  

  

  24-5 
  

  

  31 
  

  

  

  12700 
  27 
  

  

  2- 
  

  

  33 
  34 
  

  

  40 
  

  

  ■JO 
  

  

  4900 
  33 
  

  

  32 
  

  

  39 
  38 
  

  

  45 
  

  

  44 
  

  

  48 
  

  

  

  50 
  

  

  52 
  

  

  

  104300 
  10 
  

  

  10-5 
  

  

  13-5 
  14-5 
  

  

  18-5 
  

  

  20 
  

  

  49600 
  13 
  

  

  

  17 
  

  

  22 
  

  

  

  18300 
  18 
  

  

  

  22 
  

  

  28-5 
  

  

  

  5540 
  25 
  

  

  26-o 
  

  

  30 
  32 
  

  

  35 
  

  

  •".7 
  

  

  3730 
  27 
  

  

  28 
  

  

  32 
  33 
  

  

  36 
  

  

  37 
  

  

  29 
  

  

  

  40 
  

  

  42 
  

  

  

  130700 
  7 
  

  

  

  10-5 
  

  

  16 
  

  

  

  60300 
  11 
  

  

  

  15 
  

  

  18-5 
  

  

  

  7000 
  22 
  

  

  21 
  

  

  26 
  25 
  

  

  30 
  

  

  29 
  

  

  34 
  

  

  

  35 
  

  

  36 
  

  

  

  Phil. 
  Map. 
  S. 
  6. 
  Vol. 
  3. 
  No. 
  17. 
  May 
  1902. 
  2 
  M 
  

  

  