﻿360 
  Messrs. 
  De 
  La 
  Rue, 
  Miiller, 
  and 
  Spottiswoode 
  on 
  [Apr. 
  8, 
  

  

  Eig. 
  3. 
  

   V 
  2 
  

  

  The 
  primary 
  wire 
  p 
  p' 
  of 
  a 
  small 
  induction-coil, 
  both 
  with 
  and 
  without 
  the 
  

   iron 
  core, 
  was 
  introduced 
  into 
  the 
  circuit 
  as 
  well 
  as 
  the 
  vacuum-tube 
  V 
  ; 
  to 
  

   the 
  secondary 
  wire 
  s 
  s' 
  of 
  the 
  induction-coil 
  was 
  connected 
  a 
  second 
  vacuum- 
  

   tube, 
  V 
  2 
  . 
  Under 
  these 
  circumstances 
  there 
  was 
  no 
  change 
  in 
  the 
  

   appearance 
  of 
  the 
  discharge 
  in 
  V, 
  in 
  consequence 
  of 
  the 
  introduction 
  

   of 
  the 
  induction-coil, 
  the 
  terminals 
  being 
  still 
  surrounded 
  by 
  the 
  soft 
  

   nebulous 
  light 
  before 
  spoken 
  of 
  : 
  no 
  luminosity 
  appeared 
  in 
  the 
  second 
  

   vacuum-tube 
  V 
  2 
  in 
  connexion 
  with 
  the 
  secondary 
  wire 
  of 
  the 
  induction- 
  

   coil, 
  except 
  on 
  making 
  and 
  breaking 
  the 
  connexion 
  with 
  the 
  battery. 
  At 
  

   other 
  times 
  there 
  was 
  evidently 
  no 
  fluctuation 
  in 
  the 
  continuous 
  dis- 
  

   charge, 
  no 
  periodic 
  increase 
  or 
  diminution 
  of 
  flow, 
  and 
  consequently 
  

   no 
  induced 
  current 
  in 
  the 
  secondary 
  wire 
  s 
  s' 
  of 
  the 
  induction-coil. 
  

  

  In 
  the 
  second 
  experiment 
  wires 
  were 
  also 
  led 
  from 
  the 
  terminals 
  of 
  the 
  

   battery 
  (all 
  other 
  things 
  remaining 
  as 
  before) 
  to 
  the 
  coil-accumulator 
  as 
  

   in 
  fig. 
  4 
  ; 
  then 
  immediately 
  the 
  discharge 
  in 
  Y 
  became 
  stratified 
  and 
  

   the 
  secondary 
  vacuum-tube 
  V 
  2 
  lighted 
  up, 
  clearly 
  showing 
  that 
  under 
  

   these 
  circumstances 
  a 
  fluctuation 
  in 
  the 
  discharge 
  really 
  occurs 
  on 
  the 
  

   appearance 
  of 
  stratification. 
  

  

  The 
  brilliancy 
  of 
  the 
  discharge 
  in 
  V 
  2 
  (the 
  induced 
  current 
  passes 
  through 
  

   complicated 
  vacuum-tubes 
  through 
  which 
  the 
  primary 
  current 
  cannot 
  

   pass) 
  depends 
  greatly 
  on 
  the 
  quality 
  and 
  quantity 
  of 
  the 
  discharge 
  in 
  

   the 
  primary 
  vacuum-tube 
  V. 
  Under 
  some 
  circumstances 
  the 
  secondary 
  

   discharge 
  is 
  extremely 
  feeble, 
  and 
  the 
  illumination 
  in 
  V 
  2 
  barely 
  visible 
  ; 
  

   under 
  others 
  it 
  is 
  very 
  brilliant. 
  

  

  Preparations 
  are 
  being 
  made 
  to 
  render 
  evident 
  induced 
  currents 
  in 
  the 
  

  

  