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  DESCRIPTION 
  OF 
  A 
  GALVANIC 
  BATTERY 
  

  

  one 
  permanent 
  galvanic 
  arrangement, 
  but 
  are 
  only 
  temporarily 
  con- 
  

   nected 
  by 
  means 
  of 
  movable 
  conductors 
  and 
  cups 
  of 
  mercury. 
  The 
  

   whole 
  is 
  constructed 
  in 
  reference 
  to 
  the 
  principle 
  well 
  understood 
  of 
  

   producing 
  electricity 
  of 
  greater 
  or 
  less 
  intensity, 
  by 
  a 
  change 
  in 
  the 
  

   method 
  of 
  uniting 
  the 
  several 
  elements 
  with 
  each 
  other. 
  

  

  The 
  apparatus 
  consists 
  of 
  eighty-eight 
  elements 
  or 
  pairs, 
  composed 
  

   of 
  plates 
  of 
  rolled 
  zinc 
  nearly 
  one 
  eighth 
  of 
  an 
  inch 
  thick, 
  nine 
  inches 
  

   wide, 
  and 
  twelve 
  inches 
  long, 
  inserted 
  into 
  copper 
  cases 
  open 
  at 
  top 
  

   and 
  bottom. 
  Eleven 
  of 
  these 
  elements 
  are 
  suspended 
  together 
  from 
  

   two 
  cross 
  pieces 
  of 
  wood, 
  and 
  the 
  whole 
  number 
  is 
  thus 
  arranged 
  in 
  

   eight 
  sets, 
  of 
  eleven 
  in 
  each. 
  These 
  are 
  supported 
  by 
  the 
  ends 
  of 
  the 
  

   cross-pieces 
  in 
  a 
  strong 
  wooden 
  frame, 
  so 
  as 
  to 
  be 
  immersed 
  in 
  eight 
  

   separate 
  troughs 
  : 
  they 
  thus 
  form 
  as 
  many 
  independent 
  batteries, 
  which 
  

   can 
  be 
  used 
  separately 
  or 
  together 
  as 
  the 
  occasion 
  may 
  require. 
  Each 
  

   trough 
  is 
  divided 
  into 
  eleven 
  cells 
  by 
  wooden 
  partitions 
  coated 
  with 
  

   cement. 
  If 
  one 
  of 
  the 
  cells 
  be 
  charged 
  with 
  dilute 
  acid, 
  a 
  single 
  ele- 
  

   ment 
  may 
  be 
  excited 
  without 
  producing 
  action 
  in 
  any 
  other 
  part 
  of 
  

   the 
  battery. 
  Each 
  set 
  or 
  battery 
  may 
  also 
  be 
  lifted 
  separately 
  from 
  

   the 
  frame 
  by 
  its 
  cross 
  pieces, 
  without 
  disturbing 
  the 
  other 
  parts 
  of 
  the 
  

   apparatus. 
  

  

  The 
  elements 
  remain 
  stationary, 
  while 
  the 
  troughs 
  are 
  raised 
  to 
  them 
  

   on 
  a 
  movable 
  platform 
  by 
  the 
  common 
  application 
  of 
  a 
  wheel 
  and 
  

   pinion. 
  

  

  The 
  general 
  arrangement 
  of 
  the 
  whole 
  may 
  be 
  seen 
  at 
  once 
  by 
  a 
  

   reference 
  to 
  the 
  perspective 
  drawing, 
  fig. 
  1, 
  Plate 
  XXII. 
  a 
  a, 
  &c. 
  

   represent 
  the 
  cross 
  pieces 
  resting 
  on 
  the 
  upper 
  part 
  of 
  the 
  frame 
  of 
  the 
  

   machine 
  ; 
  c 
  c 
  is 
  the 
  movable 
  platform. 
  

  

  A 
  perspective 
  view 
  of 
  one 
  of 
  the 
  elements 
  on 
  a 
  larger 
  scale 
  is 
  given 
  

   in 
  fig. 
  3. 
  a 
  a 
  are 
  two 
  cups 
  of 
  cast 
  copper, 
  with 
  a 
  broad 
  stem 
  on 
  the 
  

   bottom 
  ; 
  one 
  soldered 
  to 
  the 
  zinc 
  plate, 
  and 
  the 
  other 
  to 
  the 
  copper 
  

   case. 
  The 
  cavity 
  in 
  these 
  cups 
  is 
  about 
  three 
  eighths 
  of 
  an 
  inch 
  

   wide, 
  a 
  little 
  more 
  than 
  an 
  inch 
  long, 
  and 
  half 
  an 
  inch 
  deep. 
  The 
  

   cups 
  being 
  well 
  amalgamated 
  and 
  partially 
  filled 
  with 
  mercury, 
  receive 
  

   the 
  ends 
  of 
  the 
  copper 
  conductors 
  which 
  unite 
  the 
  several 
  elements. 
  

  

  For 
  the 
  purpose 
  of 
  suspension, 
  a 
  slip 
  of 
  copper, 
  b 
  b, 
  with 
  a 
  hole 
  in 
  

   it. 
  is 
  soldered 
  to 
  each 
  upper 
  corner 
  of 
  the 
  copper 
  case 
  ; 
  these 
  fit 
  loosely 
  

  

  