﻿516 
  Prof. 
  Wellisch 
  and 
  Dr. 
  Woodrow 
  : 
  Experiments 
  

  

  curves 
  are 
  given 
  in 
  fig. 
  2. 
  The 
  values 
  given 
  for 
  the 
  ratio 
  r 
  

   are 
  for 
  the 
  ratio 
  of 
  the 
  current 
  at 
  a 
  pressure 
  of 
  760 
  mm. 
  to 
  

   that 
  at 
  a 
  pressure 
  of 
  284 
  mm. 
  The 
  distance 
  ^=2*68 
  cm. 
  is 
  

   that 
  from 
  the 
  polonium 
  to 
  the 
  middle 
  of 
  the 
  ionization 
  vessel. 
  

   This 
  notation 
  will 
  be 
  used 
  throughout 
  the 
  present 
  paper. 
  

   The 
  current 
  is 
  in 
  scale-divisions 
  per 
  second. 
  

  

  Fio-. 
  2. 
  

  

  t 
  

  

  .*2 
  

  

  ^-o-B 
  

  

  

  

  

  

  

  

  C 
  

  

  (P 
  

  

  2=^= 
  — 
  

  

  ■O 
  On"" 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  A= 
  LONCI 
  

   B 
  = 
  TRAM 
  

  

  TUDINAL 
  

   SVERSE 
  

  

  FIELD 
  

  

  

  

  

  

  

  

  

  

  

  

  

  I0OO 
  1200 
  I40O 
  1600 
  

  

  //<7/As 
  per 
  c/p. 
  

  

  It 
  will 
  be 
  seen 
  from 
  fig. 
  2 
  that 
  for 
  values 
  of 
  X 
  greater 
  

   than 
  400 
  volts 
  per 
  centimetre 
  ri 
  is 
  greater 
  than 
  r 
  t 
  . 
  This 
  

   experimental 
  result 
  was 
  verified 
  in 
  several 
  subsequent 
  deter- 
  

   minations 
  and 
  appeared 
  thus 
  to 
  support 
  the 
  view 
  that 
  there 
  

   is 
  extra 
  ionization 
  produced 
  when 
  the 
  electric 
  field 
  is 
  

   longitudinal. 
  

  

  The 
  slit 
  was 
  now 
  removed 
  and 
  in 
  its 
  place 
  was 
  inserted 
  

   a 
  " 
  canal 
  " 
  system 
  consisting 
  of 
  twenty- 
  five 
  small 
  holes 
  drilled 
  

   in 
  a 
  small 
  brass 
  rod 
  6 
  mm. 
  in 
  length 
  and 
  4 
  mm. 
  in 
  diameter. 
  

   There 
  was 
  a 
  central 
  " 
  canal 
  " 
  1 
  mm. 
  in 
  diameter 
  surrounded 
  

   by 
  twenty-four 
  smaller 
  "canals/' 
  each 
  0*4 
  mm. 
  in 
  diameter. 
  

   In 
  this 
  manner 
  the 
  electric 
  field 
  was 
  more 
  rigorously 
  longi- 
  

   tudinal 
  or 
  transverse 
  to 
  the 
  alpha 
  particle 
  trajectories 
  than 
  

   when 
  the 
  slit 
  was 
  employed. 
  A 
  value 
  was 
  obtained 
  for 
  

   the 
  range 
  of 
  the 
  alpha 
  particle 
  identical 
  with 
  that 
  found 
  

   previously. 
  

  

  The 
  values 
  obtained 
  for 
  n 
  and 
  r 
  t 
  are 
  given 
  in 
  Table 
  II. 
  T 
  

   and 
  the 
  corresponding 
  curves 
  are 
  shown 
  in 
  fig. 
  3. 
  

  

  In 
  Older 
  to 
  determine 
  whether 
  the 
  scattering 
  of 
  the 
  

   alpha 
  particles 
  produced 
  any 
  effect 
  on 
  the 
  relative 
  values 
  

   of 
  n 
  and 
  n 
  when 
  the 
  canals 
  were 
  employed, 
  readings 
  were 
  

   taken 
  of 
  the 
  current 
  with 
  the 
  polonium 
  at 
  different 
  distances 
  

   from 
  the 
  middle 
  of 
  the 
  ionization 
  vessel. 
  The 
  electric 
  

  

  