﻿756 
  Mr. 
  W. 
  T. 
  Kennedy 
  on 
  the 
  Active 
  Deposit 
  

  

  Many 
  o£ 
  the 
  results 
  obtained 
  in 
  the 
  present 
  investigation 
  

   go 
  to 
  support 
  this 
  view, 
  and 
  one 
  in 
  particular 
  is 
  of 
  special 
  

   interest. 
  

  

  In 
  this 
  experiment 
  the 
  electrodes 
  were 
  2 
  mm. 
  apart, 
  the 
  

   salt 
  was 
  placed 
  1'3 
  mm. 
  below 
  the 
  electrodes 
  in 
  the 
  exposing 
  

   vessel, 
  and 
  the 
  exposures 
  were 
  made 
  under 
  different 
  voltages 
  

   in 
  air 
  at 
  a 
  pressure 
  o£ 
  9 
  mm. 
  The 
  exposures 
  were 
  made 
  

   first 
  with 
  the 
  two 
  electrodes 
  at 
  the 
  same 
  potential, 
  and 
  then 
  

   with 
  them 
  at 
  different 
  potentials 
  ranging 
  in 
  extent 
  up 
  to 
  

   1150 
  volts. 
  

  

  The 
  results 
  of 
  the 
  various 
  activity 
  measurements 
  are 
  given 
  

   in 
  Table 
  IX., 
  and 
  curves 
  drawn 
  fiom 
  these 
  numbers 
  are 
  shown 
  

   in 
  fig. 
  15 
  (PI. 
  XXII.). 
  

  

  Table 
  IX. 
  

  

  Pressure 
  9 
  mm. 
  ; 
  Electrodes 
  2 
  mm. 
  apart 
  ; 
  

  

  Distance 
  of 
  Salt 
  1 
  3 
  cm. 
  

  

  Voltage. 
  

  

  Activity 
  on 
  

  

  

  Activity 
  on 
  

  

  ]S"egative 
  Electrode. 
  

  

  

  Positive 
  Electrode. 
  

  

  . 
  

  

  11-0 
  

  

  

  10-6 
  

  

  83 
  

  

  121 
  

  

  

  10-0 
  

  

  242 
  

  

  14-9 
  

  

  

  10-2 
  

  

  ! 
  467 
  

  

  15-5 
  

  

  

  103 
  

  

  523 
  

  

  15-8 
  

  

  

  11-2 
  

  

  545 
  

  

  18-6 
  

  

  

  14-2 
  

  

  605 
  

  

  17-4 
  

  

  

  13-0 
  

  

  641 
  

  

  35-8 
  

  

  

  25-0 
  

  

  683 
  

  

  19-2 
  

  

  

  13-1 
  

  

  1 
  794 
  

  

  30-7 
  

  

  

  19-2 
  

  

  928 
  

  

  30-7 
  

  

  

  25-0 
  

  

  955 
  

  

  38-7 
  

  

  

  21-6 
  

  

  1149 
  

  

  29-4 
  

  

  

  19-2 
  

  

  Note. 
  — 
  Sparking 
  potential 
  for 
  pressure 
  9 
  mm. 
  and 
  distance 
  2 
  mm. 
  — 
  460 
  volts. 
  

   (Carr, 
  Phil. 
  Trans. 
  Eoy. 
  Soc. 
  vol. 
  cci. 
  pp. 
  403-433.) 
  

  

  From 
  these 
  results 
  it 
  will 
  be 
  seen 
  that 
  when 
  the 
  potentials 
  

   of 
  the 
  two 
  plates 
  were 
  the 
  same 
  the 
  activities 
  of 
  both 
  were 
  

   alike 
  ; 
  but 
  that 
  for 
  all 
  potential-differences 
  the 
  activity 
  of 
  the 
  

   negative 
  terminal 
  was 
  greater 
  than 
  that 
  of 
  the 
  positive. 
  For 
  

   potential 
  -differences 
  from 
  200 
  to 
  450 
  volts 
  the 
  activities 
  were 
  

   practically 
  independent 
  of 
  the 
  potential-difference 
  applied. 
  

   From 
  460 
  volts 
  upward, 
  however, 
  the 
  activities 
  of 
  both 
  

   electrodes 
  increased, 
  and 
  finally 
  at 
  about 
  800 
  volts 
  again 
  

   became 
  independent 
  of 
  the 
  applied 
  potential. 
  

  

  