﻿Positive 
  Electricity, 
  

  

  833 
  

  

  phosphorescent 
  patch 
  they 
  produce 
  on 
  the 
  %villeinite 
  screen 
  

   T 
  ; 
  Irom 
  the 
  mao-netic 
  and 
  electric 
  deflexions 
  the 
  values 
  o£ 
  

   ei'm 
  and 
  v 
  can 
  be 
  deduced 
  in 
  the 
  usual 
  way. 
  Observations 
  

   were 
  made 
  simultaneously 
  of 
  the 
  deflexions 
  of 
  the 
  spots 
  on 
  

   the 
  screens 
  S 
  and 
  T 
  when 
  the 
  pressure 
  was 
  varied 
  from 
  the 
  

   largest 
  value 
  at 
  which 
  both 
  rays 
  produced 
  phosphorescence 
  

   on 
  the 
  screen 
  to 
  a 
  very 
  high 
  vacuum. 
  The 
  deflexion 
  of 
  the 
  

   cathode 
  rays 
  under 
  a 
  constant 
  magnetic 
  field 
  was 
  8 
  mm. 
  at 
  

   the 
  highest 
  pressure 
  and 
  2 
  mm. 
  at 
  the 
  lowest; 
  thus 
  the 
  

   velocity 
  of 
  the 
  cathode 
  rays 
  was 
  4 
  times 
  greater 
  at 
  the 
  lower 
  

   pressure 
  than 
  at 
  the 
  higher, 
  but 
  in 
  spite 
  of 
  this 
  large 
  change 
  

   in 
  the 
  cathode 
  rays, 
  there 
  was 
  no 
  appreciable 
  change 
  in 
  the 
  

   deflexion 
  of 
  the 
  Canalstrahlen 
  over 
  the 
  whole 
  range 
  of 
  

   pressure. 
  

  

  The 
  results 
  of 
  two 
  sets 
  of 
  experiments 
  with 
  different 
  tubes 
  

   are 
  shown 
  in 
  the 
  following 
  table. 
  

  

  By 
  equivalent 
  spark-gap 
  is 
  meant 
  the 
  distance 
  between 
  

   two 
  large 
  electrodes 
  placed 
  in 
  parallel 
  with 
  the 
  tube 
  and 
  

   adjusted 
  so 
  that 
  the 
  sparks 
  passed 
  about 
  equally 
  readily 
  

   through 
  the 
  tube 
  or 
  across 
  the 
  air-gap. 
  

  

  Deflexion 
  of 
  Canalstrahlen. 
  

  

  

  

  

  Deflexion 
  of 
  

   Cathode 
  Eays. 
  

  

  Equivalent 
  

   Spark- 
  Gap. 
  

  

  Magnetic. 
  

  

  Electrostatic, 
  

  

  mm. 
  

  

  mm. 
  

  

  mm. 
  

  

  cm. 
  

  

  6 
  

  

  6 
  

  

  6 
  

  

  •5 
  

  

  6 
  

  

  6 
  

  

  4-5 
  

  

  

  5 
  5 
  

  

  6-5 
  

  

  2-5 
  

  

  

  6-5 
  

  

  6 
  

  

  2 
  

  

  3-8 
  

  

  mm. 
  

  

  mm. 
  

  

  mm. 
  

  

  

  6 
  

  

  4 
  

  

  6-5 
  

  

  

  6 
  

  

  4-5 
  

  

  5 
  

  

  

  6 
  

  

  4 
  

  

  3 
  

  

  

  5-5 
  

  

  35 
  

  

  2 
  

  

  

  The 
  numbers 
  in 
  one 
  horizontal 
  line 
  were 
  observed 
  simulta- 
  

   neously, 
  one 
  observer 
  reading 
  the 
  deflexion 
  of 
  the 
  cathode 
  

   rays, 
  another 
  those 
  of 
  the 
  Canalstrahlen. 
  At 
  the 
  very 
  

   highest 
  pressures 
  at 
  which 
  Canalstrahlen 
  appear 
  their 
  

   deflexions 
  seem 
  greater 
  than 
  those 
  at 
  lower 
  pressures, 
  thouo-h 
  

   the 
  difference 
  is 
  on 
  quite 
  another 
  scale 
  to 
  that 
  of 
  the 
  cathode 
  

  

  