﻿258 
  Pierce 
  — 
  Applicatio7i 
  of 
  the 
  Radio- 
  Micrometer 
  

  

  intensity 
  at 
  a 
  point 
  is 
  inversely 
  as 
  the 
  square 
  of 
  the 
  distance 
  

   from 
  the 
  source, 
  we 
  obtain 
  from 
  a 
  linear 
  source 
  and 
  a 
  parabolic 
  

   receiving 
  reflector 
  an 
  integral 
  that 
  is 
  difficult 
  to 
  treat, 
  In 
  the 
  

   second 
  place, 
  we 
  cannot 
  eliminate 
  the 
  difficulties 
  arising 
  from 
  

   diffraction. 
  

  

  I 
  have 
  attempted 
  in 
  another 
  way 
  to 
  get 
  experimental 
  evi- 
  

   dence 
  of 
  the 
  significance 
  of 
  the 
  deflections 
  of 
  the 
  receiving 
  

   instrument. 
  With 
  the 
  oscillator 
  and 
  the 
  resonator 
  both 
  armed 
  

   with 
  their 
  parabolic 
  reflectors, 
  the 
  effect 
  was 
  measured 
  of 
  turn- 
  

   ing 
  the 
  oscillator 
  to 
  an 
  angle, 
  a, 
  with 
  the 
  resonator 
  about 
  the 
  com- 
  

   mon 
  optical 
  axis 
  of 
  the 
  two 
  reflectors. 
  The 
  oscillator 
  was 
  

   directly 
  in 
  front 
  of 
  the 
  resonator 
  at 
  a 
  distance 
  of 
  52 
  cm 
  , 
  and 
  the 
  

   angle 
  of 
  turning 
  was 
  read 
  off 
  in 
  degrees 
  on 
  the 
  scale 
  at 
  the 
  

   back 
  of 
  the 
  reflector 
  of 
  the 
  former. 
  The 
  headings 
  of 
  the 
  

   respective 
  columns 
  are 
  the 
  angles 
  of 
  turning. 
  In 
  the 
  columns 
  

   are 
  the 
  corresponding 
  deflections 
  of 
  the 
  receiving 
  instrument 
  

   in 
  millimeters. 
  Alternate 
  readings 
  were 
  taken. 
  

  

  30' 
  

  

  12-2 
  

  

  9-8 
  

  

  11-9 
  

  

  10-1 
  

  

  11-0 
  

  

  9 
  4 
  

  

  11-6 
  

  

  S-9 
  

  

  11-0 
  

  

  8-7 
  

  

  10-5 
  

  

  8-5 
  

  

  10-6 
  

  

  8-5 
  

  

  10-3 
  

  

  

  11-14 
  

  

  9-13 
  

  

  Ratio 
  

  

  •819 
  

  

  0° 
  

  

  45° 
  

  

  0° 
  

  

  60° 
  

  

  0° 
  

  

  90° 
  

  

  12-4 
  

  

  6'9 
  

  

  11-2 
  

  

  4-2 
  

  

  10-4 
  

  

  15 
  

  

  12-2 
  

  

  6-4 
  

  

  11-6 
  

  

  4-2 
  

  

  9'5 
  

  

  1-1 
  

  

  12-0 
  

  

  6-6 
  

  

  12-5 
  

  

  3-9 
  

  

  

  1-2 
  

  

  11-9 
  

  

  6-6 
  

  

  11-3 
  

  

  3-7 
  

  

  

  

  11-6 
  

  

  

  106 
  

  

  4-2 
  

  

  

  

  12-0 
  

  

  6-62 
  

  

  11-4 
  

  

  4-04 
  

  

  10-0 
  

  

  1-3 
  

  

  

  •552 
  

  

  

  •355 
  

  

  

  ( 
  "13 
  

  

  Other 
  values 
  obtained 
  for 
  the 
  last 
  ratio 
  

  

  Averaging 
  

  

  16 
  

  

  17 
  

  

  15 
  

  

  Now 
  if 
  the 
  wave 
  is 
  plane-polarized 
  and 
  we 
  neglect 
  the 
  effect 
  

   of 
  the 
  second 
  metallic 
  reflection 
  on 
  the 
  nature 
  of 
  the 
  polariza- 
  

   tion, 
  we 
  should 
  have 
  for 
  the 
  component 
  of 
  the 
  intensity 
  in 
  the 
  

   direction 
  of 
  the 
  resonator 
  the 
  formula 
  

  

  JJJ 
  2 
  = 
  COS 
  2 
  a. 
  

  

  Bat 
  when 
  the 
  instruments 
  were 
  at 
  right 
  angles 
  there 
  was 
  a 
  small 
  

   deflection 
  remaining 
  which 
  was 
  not 
  accounted 
  for 
  by 
  this 
  form- 
  

   ula. 
  This 
  was 
  shown 
  to 
  be 
  due 
  to 
  the 
  waves, 
  for 
  a 
  metallic 
  screen 
  

   interposed 
  nullified 
  it 
  completely. 
  Whether 
  this 
  effect 
  is 
  due 
  

   to 
  a 
  mixed 
  polarization 
  of 
  the 
  waves 
  or 
  due 
  to 
  the 
  action 
  of 
  

   the 
  waves 
  on 
  the 
  short, 
  fine 
  wires 
  perpendicular 
  to 
  the 
  resonat- 
  

   ing 
  cylinders 
  in 
  the 
  thermal-junction, 
  it 
  shows 
  a 
  component 
  of 
  

  

  