﻿218 
  Wellisch 
  and 
  Woodrow 
  — 
  Columnar 
  Ionization. 
  

  

  culated 
  that 
  the 
  cone 
  of 
  rays 
  emerging 
  from 
  the 
  slit 
  would 
  fall 
  

   entirely 
  within 
  the 
  electrodes 
  and 
  that 
  no 
  alpha 
  particle 
  could 
  

   reach 
  an 
  electrode 
  except 
  by 
  scattering. 
  

  

  The 
  values 
  obtained 
  for 
  r 
  x 
  and 
  r 
  % 
  for 
  different 
  values 
  of 
  the 
  

   electric 
  field 
  X 
  are 
  given 
  below, 
  and 
  the 
  corresponding 
  curves 
  

   i"n 
  fig. 
  2. 
  The 
  values 
  given 
  for 
  the 
  ratio 
  r 
  are 
  for 
  

  

  Fig. 
  2. 
  

  

  Ratio 
  : 
  r. 
  

  

  

  

  

  

  

  — 
  Q 
  

  

  

  C 
  

  

  

  

  

  

  

  

  r 
  

  

  

  

  

  

  

  

  

  

  

  A= 
  LONGI 
  

   B 
  = 
  TRAN 
  

  

  TUDINAL 
  

   SVERSE 
  

  

  HELD 
  

  

  

  

  

  

  

  

  

  

  

  

  

  2 
  

  

  DO 
  

  

  AC 
  

  

  )0 
  6C 
  

  

  )0 
  8C 
  

  

  

  

  10 
  

  

  oo 
  

  

  1200 
  

  

  1400 
  

  

  160 
  

  

  Volts 
  per 
  cm. 
  

  

  the 
  ratio 
  of 
  the 
  current 
  at 
  a 
  pressure 
  of 
  760 
  mm 
  to 
  that 
  at 
  a 
  

   pressure 
  of 
  284 
  mm 
  . 
  The 
  distance 
  d= 
  2-68 
  cm 
  is 
  that 
  from 
  the 
  

   polonium 
  to 
  the 
  middle 
  of 
  the 
  ionization 
  vessel. 
  This 
  nota- 
  

   tion 
  will 
  be 
  used 
  throughout 
  the 
  present 
  paper. 
  The 
  current 
  

   is 
  in 
  scale 
  divisions 
  per 
  second. 
  

  

  Table 
  I. 
  

   d=2 
  , 
  68cm.; 
  r=i 
  7 
  eoA'28t- 
  

  

  

  Longitudinal 
  Field. 
  

  

  Transverse 
  Field. 
  

  

  p 
  

  

  mm. 
  

  

  X 
  

  

  volts/cm. 
  

  

  ih 
  

  

  77. 
  

  

  X. 
  

  

  iu 
  

  

  77. 
  

  

  160 
  

  

  284 
  

  

  770 
  

   770 
  

   770 
  

   770 
  

   770 
  

   770 
  

  

  1565 
  

  

  1565 
  

  

  25 
  

  

  50 
  

  

  105 
  

  

  525 
  

  

  1045 
  

  

  1575 
  

  

  0-65 
  

   1-22 
  

   3-51 
  

   3-88 
  

   4-05 
  

   4-46 
  

   4-53 
  

   4-61 
  

  

  2-88 
  

   3-18 
  

   3-32 
  

   3-66 
  

   3-71 
  

   3-78 
  

  

  625 
  

  

  625 
  

  

  4 
  

  

  20 
  

  

  42 
  

  

  125 
  

  

  210 
  

  

  625 
  

  

  0*43 
  

   0-82 
  

   1-91 
  

   2-53 
  

   2-80 
  

   2-99 
  

   2-96 
  

   2-98 
  

  

  233 
  

   3-09 
  

   3 
  42 
  

   3-65 
  

   3-62 
  

   3-64 
  

  

  