﻿172 
  Mr. 
  D. 
  E. 
  Roberts 
  on 
  the 
  Effect 
  of 
  Temperature 
  and 
  

   Table 
  II.— 
  G 
  I. 
  12 
  a. 
  Temp. 
  20° 
  C. 
  

  

  £ 
  kgss. 
  

  

  Transverse 
  Magnetization. 
  

  

  Longitudinal 
  

  

  Magnetization. 
  

  

  8U$. 
  

  

  Maximum 
  

   (E/-K)/R. 
  01 
  1|$. 
  

  

  Minimum 
  

   (R'-B)/K. 
  %L§. 
  

  

  (K 
  l 
  -E)/R. 
  

  

  573 
  

  

  0-40 
  

  

  0-008 
  

  

  0010 
  

  

  9-60 
  

  

  1-04 
  

  

  0-020 
  

  

  0-020 
  

  

  14-78 
  

  

  216 
  

  

  0040 
  

  

  0-040 
  

  

  20-3 
  

  

  391 
  

  

  0-070 
  

  

  0075 
  

  

  21-9 
  

  

  4-56 
  

  

  0-083 
  

  

  0-082 
  

  

  232 
  

  

  4-75 
  

  

  0-092 
  

  

  0-092 
  

  

  26-15 
  

  

  5-91 
  

  

  0-115 
  

  

  

  29-75 
  

  

  7-36 
  

  

  0-148 
  

  

  

  33-98 
  

  

  9-28 
  

  

  0-172 
  

  

  

  352 
  

  

  9-89 
  

  

  0-189 
  

  

  

  36-4 
  

  

  10-5 
  

  

  0-194 
  

  

  

  fields 
  the 
  agreement 
  is 
  better. 
  In 
  the 
  orientation 
  experi- 
  

   ments, 
  assuming 
  formula 
  (1) 
  to 
  be 
  true, 
  it 
  is 
  reasonable 
  to 
  

   expect 
  that 
  (R' 
  — 
  R)/R 
  should 
  now 
  be 
  given 
  by 
  an 
  equation 
  

   such 
  as 
  

  

  where 
  .0n 
  denotes 
  the 
  component 
  o£ 
  the 
  field 
  along 
  the 
  axis, 
  

   and 
  .f)x 
  that 
  at 
  right 
  angles. 
  

  

  Or 
  

  

  R 
  f 
  -R 
  

   R 
  

  

  = 
  A(.j5 
  cos 
  0) 
  m 
  + 
  A! 
  (Jo 
  sin 
  4>) 
  m 
  \ 
  

  

  and 
  this, 
  since 
  ,Q 
  is 
  kept 
  constant, 
  may 
  be 
  written 
  

   R'-R 
  

  

  R 
  

  

  = 
  2acos 
  w 
  e£ 
  + 
  2a'sin 
  m 
  '</>. 
  

  

  (2) 
  

  

  Here 
  2a 
  and 
  2a' 
  are 
  constants, 
  and 
  are 
  experimentally 
  deter- 
  

   mined 
  when 
  = 
  or 
  7r/2 
  respectively. 
  

  

  Applying 
  equation 
  (2) 
  to 
  the 
  experimental 
  points 
  given 
  in 
  

   fig. 
  2, 
  curve 
  III., 
  putting 
  2a 
  = 
  9'80 
  and 
  2a' 
  = 
  0*202, 
  it 
  was 
  first 
  

   found 
  that 
  putting 
  m 
  = 
  m' 
  = 
  l*74 
  5 
  ,fair 
  agreement 
  between 
  the 
  

   calculated 
  and 
  the 
  observed 
  values 
  for 
  intermediate 
  values 
  

  

  