﻿FOR 
  PRODUCING 
  ELECTRICITY. 
  221 
  

  

  large 
  frame. 
  Besides 
  this, 
  when 
  the 
  plates 
  are 
  once 
  entered, 
  they 
  are 
  

   not 
  required 
  to 
  be 
  entirely 
  withdrawn 
  from 
  the 
  cells 
  until 
  the 
  end 
  of 
  

   the 
  series 
  of 
  experiments 
  ; 
  since 
  the 
  acid 
  descends 
  as 
  the 
  plates 
  are 
  with- 
  

   drawn, 
  and 
  finally 
  fills 
  but 
  little 
  more 
  than 
  three-fourths 
  of 
  the 
  capa- 
  

   city 
  of 
  the 
  cells. 
  When 
  a 
  plate 
  accidentally 
  catches 
  on 
  the 
  side 
  of 
  the 
  

   cell, 
  the 
  battery 
  to 
  which 
  it 
  belongs 
  is 
  gently 
  raised 
  in 
  its 
  place 
  and 
  

   the 
  plate 
  adjusted. 
  

  

  This 
  apparatus 
  readily 
  furnishes 
  the 
  means 
  of 
  making 
  comparative 
  

   experiments 
  on 
  the 
  difference 
  produced 
  by 
  partial 
  and 
  perfect 
  insula- 
  

   tion. 
  When 
  no 
  higher 
  degree 
  of 
  intensity 
  is 
  required 
  than 
  that 
  afforded 
  

   by 
  eight 
  pairs 
  of 
  plates, 
  perfect 
  insulation 
  is 
  obtained 
  by 
  the 
  eight 
  

   separate 
  troughs. 
  In 
  higher 
  degrees 
  of 
  intensity 
  the 
  partitions 
  in 
  the 
  

   troughs 
  furnish 
  the 
  means 
  of 
  perfectly 
  insulating 
  forty-eight 
  of 
  the 
  

   elements: 
  this 
  is 
  effected 
  by 
  simply 
  charging 
  with 
  acid 
  every 
  other 
  cell 
  

   in 
  each 
  of 
  the 
  troughs, 
  and 
  connecting 
  the 
  corresponding 
  element 
  by 
  

   conductors, 
  which 
  pass 
  over 
  the 
  intermediate 
  elements 
  without 
  touch- 
  

   ing 
  them 
  : 
  with 
  this 
  arrangement 
  we 
  have 
  six 
  cells 
  in 
  each 
  trough 
  

   separated 
  from 
  one 
  another 
  by 
  a 
  cell 
  without 
  acid, 
  or 
  in 
  effect 
  by 
  a 
  

   stratum 
  of 
  air. 
  For 
  comparison 
  with 
  these 
  a 
  set 
  of 
  troughs 
  has 
  been 
  

   constructed 
  without 
  partitions. 
  

  

  The 
  want 
  of 
  perfect 
  insulation 
  is 
  not 
  very 
  perceptible 
  in 
  the 
  com- 
  

   mon 
  experiments 
  of 
  the 
  deflagration 
  of 
  large 
  and 
  perfect 
  conductors 
  ; 
  

   but 
  where 
  the 
  decomposition 
  of 
  a 
  liquid 
  is 
  attempted, 
  or 
  the 
  battery 
  

   required 
  to 
  act 
  on 
  a 
  small 
  or 
  imperfect 
  conductor, 
  the 
  loss 
  of 
  power 
  is 
  

   very 
  great, 
  the 
  apparatus 
  partially 
  discharging 
  itself 
  through 
  its 
  own 
  

   liquid, 
  and 
  the 
  intensity 
  at 
  the 
  poles 
  does 
  not 
  increase 
  with 
  a 
  short 
  

   interruption 
  of 
  the 
  current. 
  

  

  There 
  is 
  also 
  considerable 
  loss 
  on 
  account 
  of 
  imperfect 
  insulation 
  

   even 
  in 
  the 
  case 
  of 
  low 
  intensity, 
  and 
  when 
  the 
  poles 
  are 
  connected 
  by 
  

   a 
  perfect 
  conductor. 
  In 
  one 
  experiment 
  with 
  an 
  arrangement 
  of 
  five 
  

   pairs, 
  and 
  the 
  poles 
  united 
  by 
  a 
  conductor 
  composed 
  of 
  thirty 
  strands 
  

   of 
  copper 
  bell 
  wire, 
  each 
  forty 
  feet 
  long, 
  the 
  loss 
  was 
  found 
  to 
  be 
  at 
  

   least 
  one 
  seventh, 
  as 
  measured 
  by 
  the 
  quantity 
  of 
  zinc 
  surface 
  required 
  

   to 
  be 
  immersed 
  in 
  order 
  to 
  produce 
  the 
  same 
  magnetic 
  effect 
  I 
  would 
  

   infer 
  from 
  this 
  that 
  the 
  most 
  perfect 
  of 
  all 
  Dr 
  Hare's 
  ingenious 
  galvanic 
  

   arrangements 
  is 
  that 
  in 
  which 
  the 
  elements 
  dip 
  into 
  separate 
  glass 
  

   vol. 
  v.— 
  3 
  F 
  

  

  