﻿682 
  

  

  Dr. 
  W. 
  F. 
  G. 
  Swann 
  on 
  a 
  Case 
  of 
  

  

  It 
  will 
  be 
  noticed 
  from 
  the 
  curves 
  in 
  figs. 
  2 
  and 
  3, 
  which 
  

   are 
  drawn 
  to 
  correspond 
  to 
  the 
  observations, 
  that, 
  for 
  example, 
  

   when 
  C 
  is 
  positively 
  charged, 
  A 
  rises 
  in 
  potential, 
  while 
  

  

  

  

  

  

  

  

  F 
  

  

  Lg.2. 
  

  

  

  

  

  

  

  

  

  

  

  

  1 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  ■£ 
  t>o 
  

  

  w 
  

   '■J 
  

  

  ^ 
  So 
  

  

  

  \ 
  

  

  \ 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  ( 
  

  

  iirirC- 
  

  

  (or 
  plate 
  A 
  

  

  

  C 
  l-einq 
  

  

  c/iaraed 
  

  

  bosi 
  

  

  tiveh 
  

  

  

  

  

  \ 
  

  

  

  

  J 
  J- 
  i 
  J 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  \ 
  

  

  K 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  Tim 
  

  

  in 
  

  

  hoars 
  

  

  

  

  

  

  

  

  

  

  — 
  -e— 
  

  

  

  72 
  

  

  

  

  

  

  

  h- 
  

  

  

  

  1 
  

  

  

  

  

  

  

  / 
  / 
  

  

  e 
  

  

  ! 
  

  

  

  

  

  

  --9 
  

  

  

  

  

  $ 
  '° 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  ^ 
  so 
  

  

  

  

  

  A 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  / 
  

   1 
  

  

  1 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  Curvt 
  for 
  plait 
  'B 
  , 
  

  

  C 
  .lei 
  no 
  ckcLraed 
  positively 
  

  

  ^ 
  SO 
  

  

  

  

  1 
  

  

  

  

  | 
  | 
  

  

  

  

  

  

  

  

  s: 
  70 
  

  

  

  \ 
  

  

  

  

  

  

  

  

  

  

  

  

  

  B 
  falls 
  ; 
  the 
  electrometer 
  readings 
  being 
  practically 
  of 
  the 
  

   same 
  magnitudes 
  but 
  of 
  opposite 
  sign 
  for 
  the 
  two 
  plates. 
  

   The 
  reason 
  for 
  this 
  will 
  readily 
  appear 
  when 
  we 
  consider 
  the 
  

   theory 
  of 
  the 
  experiment, 
  which 
  we 
  will 
  now 
  proceed 
  to 
  do. 
  

  

  (2) 
  Theory 
  of 
  the 
  Experiment. 
  — 
  In 
  the 
  first 
  place 
  we 
  may 
  

   remark 
  that 
  if 
  the 
  conductivity 
  is 
  due 
  to 
  ions 
  existing 
  in 
  the 
  

   dielectric 
  which 
  are 
  not 
  produced 
  by 
  the 
  field, 
  or 
  in 
  fact 
  if 
  

   the 
  conductivity 
  is 
  brought 
  about 
  by 
  any 
  action 
  taking 
  place 
  

   in 
  conformity 
  with 
  Ohm's 
  law, 
  neither 
  the 
  plate 
  A 
  nor 
  the 
  

   plate 
  B 
  should 
  alter 
  in 
  potential 
  as 
  time 
  goes 
  on. 
  For, 
  if 
  V 
  

   is 
  the 
  potential 
  of 
  0, 
  A 
  and 
  B 
  being 
  both 
  initially 
  zero, 
  and 
  

  

  