﻿1875.] 
  Stratification 
  in 
  Electrical 
  Discharges 
  in 
  vacuo. 
  359 
  

  

  selected 
  for 
  these 
  experiments 
  were 
  those 
  in 
  which 
  the 
  stratification 
  did 
  

   not 
  appear 
  at 
  all. 
  

  

  When 
  the 
  battery, 
  already 
  in 
  connexion 
  with 
  the 
  vacuum-tube, 
  was 
  also 
  

   joined, 
  as 
  in 
  fig. 
  2, 
  on 
  to 
  one 
  or 
  more 
  coil-condensers 
  (coupled 
  to 
  introduce 
  

   a 
  greater 
  length 
  of 
  wire) 
  in 
  the 
  following 
  manner, 
  then 
  immediately 
  well- 
  

   defined 
  stratifications 
  appeared 
  in 
  the 
  vacuum-tube. 
  

  

  Fig. 
  2. 
  

  

  S 
  Z 
  represents 
  the 
  battery, 
  V 
  the 
  vacuum-tube, 
  C 
  the 
  coil-condenser 
  ; 
  one 
  

   terminal 
  is 
  connected 
  with 
  the 
  end 
  A 
  of 
  the 
  wire 
  A 
  A', 
  and 
  the 
  other 
  terminal 
  

   with 
  the 
  end 
  B 
  of 
  the 
  second 
  wire 
  B 
  B'; 
  connexions 
  are 
  also 
  led 
  to 
  the 
  wires 
  

   of 
  the 
  vacuum-tube. 
  The 
  ends 
  A' 
  and 
  B' 
  are 
  left 
  free 
  ; 
  and 
  it 
  is 
  clear 
  

   that 
  the 
  coil 
  forms 
  a 
  sort 
  of 
  Leyden 
  jar 
  when 
  thus 
  used 
  : 
  an 
  interval, 
  

   however 
  short 
  it 
  may 
  be, 
  must 
  elapse 
  in 
  accumulating 
  a 
  charge 
  which 
  at 
  

   intervals 
  discharges 
  itself 
  and 
  causes 
  a 
  greater 
  flow 
  in 
  the 
  vacuum-tube 
  in 
  

   addition 
  to 
  that 
  which 
  passes 
  continuously. 
  It 
  may 
  be 
  stated 
  that 
  the 
  

   capacity 
  of 
  the 
  accumulator 
  has 
  to 
  be 
  carefully 
  adjusted 
  to 
  prevent 
  any 
  

   cessation 
  of 
  the 
  current, 
  to 
  avoid, 
  in 
  fact, 
  a 
  snapping 
  discharge 
  at 
  distant 
  

   intervals. 
  The 
  periodic 
  overflows, 
  so 
  to 
  speak, 
  which 
  increase 
  the 
  current 
  

   from 
  time 
  to 
  time, 
  would 
  seem 
  to 
  have 
  a 
  tendency 
  to 
  cause 
  an 
  interfer- 
  

   ence 
  of 
  the 
  current-waves, 
  and 
  to 
  produce 
  nodes 
  of 
  greater 
  resistance 
  in 
  

   the 
  medium, 
  as 
  evinced 
  by 
  the 
  stratification 
  which 
  becomes 
  apparent. 
  To 
  

   the 
  eye 
  no 
  pulsation 
  in 
  the 
  current 
  is 
  apparent 
  ; 
  and 
  in 
  order 
  to 
  convince 
  

   ourselves 
  whether 
  or 
  not 
  there 
  was 
  really 
  any 
  fluctuation 
  in 
  the 
  current 
  

   when 
  the 
  apparatus 
  was 
  thus 
  coupled 
  up 
  with 
  the 
  battery, 
  we 
  made 
  

   several 
  experiments, 
  and 
  ultimately 
  hit 
  upon 
  the 
  following 
  arrange- 
  

   ment 
  (fig. 
  3) 
  : 
  — 
  

  

  