186  ME.  Gr.  G-OEE  ON  THE  PEOPEETIES  OP  ELECTEO-DEPOSITED  ANTIMONY. 
kinds  of  metal  in  the  first  liquid ; but  the  most  important  are,  the  temperature  and 
density  of  the  solution,  the  strength  of  the  battery,  the  state  of  the  depositing  liquid, 
and  the  physical  condition  of  the  receiving  surface ; if  the  battery  is  nearly  exhausted 
in  power,  the  solution  unequal  in  density  from  long-continued  working  and  neglected 
stirring,  and  the  receiving  surface  rough  or  unclean,  the  deposited  metal  will  be  amor- 
phous and  smooth  in  the  lower  and  denser  part  of  the  liquid,  and  crystalline  and  warty 
in  the  upper  and  lighter  portion.  If  the  hquid  is  boiling  hot,  or  if  it  is  verj-  dilute  or 
contains  much  free  acid,  the  deposit  will  be  grey  throughout. 
5.  The  production  of  either  of  these  deposits  is  so  easy  that  the  simplest  of  conditions 
will  suffice.  To  produce  the  amorphous  variety,  take  a small  battery  consisting  of  one 
or  two  pairs  of  zinc  and  platinized  silver  plates,  charged  with  a mixture  of  one  measure 
of  sulphuric  acid  and  twenty  measures  of  water,  and  having  prepared  a small  quantity 
of  the  mixture  of  chloride  of  antimony  and  tartar-emetic,  connect  with  the  terminal 
silver  a piece  of  commercial  antimony  (“best  French  regulus”)  of  the  same  amount  of 
immersed  surface  as  one  of  the  battery -plates,  and  immerse  it  in  the  hquid  as  an  anode, 
and  for  a receiving  surface  immerse  a piece  of  clean  polished  silver  or  copper  of  about 
one-half  the  amount  of  surface  of  the  antimony ; connect  it  by  a silver  or  copper  wire 
with  the  negative  pole  of  the  battery ; suspend  it  vertically  in  the  lower  part  of  the 
depositing  liquid  at  a few  inches  from  the  anode,  and  protect  the  connecting  ufire  from 
receiving  a deposit  near  the  surface  of  the  liquid  by  a piece  of  gutta-percha  tube,  glass 
tube,  or  by  a layer  of  varnish  formed  by  dissolving  pure  gutta  percha  in  bisulphide  of 
carbon  to  the  consistence  of  treacle.  A perfectly  bright  deposit  of  amorphous  antimony 
will  immediately  be  formed,  and  will,  if  the  electric  power  is  rather  great,  exhibit  a 
scaly  surface  after  half  an  hour’s  action ; but  by  further  continuance  the  scaliness  will 
cease,  and  a firm  coherent  deposit  of  perfect  brightness,  and  of  similar  appearance  to 
highly  polished  steel,  will  be  produced.  If  the  electric  power  is  too  great,  the  deposit 
will  be  granular  and  loose.  Much  impure  matter  will  appear  upon  the  anode  dui’ing 
the  process,  especially  if  “common  bowl  regulus”  is  used,  and  may  be  removed  by 
means  of  a hard  brush  and  dilute  hydrochloric  acid.  There  is  no  depositing  liquid  with 
which  I am  acquainted,  of  any  metal,  which  will  bear  so  great  a variation  of  electric 
power  without  deteriorating  the  quality  of  the  deposit,  as  that  composed  of  taitar- 
emetic  dissolved  to  saturation  in  hydrochlorate  of  terchloride  of  antimony ; good  amor- 
phous deposits  have  been  obtained  in  it  with  batteries  varying  from  one  to  thirty-six 
pah’s  in  intensity. 
6.  To  produce  a crystalline  deposit,  prepare  a similar  quantity  of  the  second  liquid, 
and  proceed  in  exactly  the  same  manner,  except  that  a much  larger  recebiug  surface 
should  be  used  in  consequence  of  the  greater  tendency  to  a sandy  deposit ; and  the  pro- 
tecting tube  or  varnish  may  be  omitted.  In  this  case  the  deposit  is  grey,  and  frequently 
of  a dull  aspect,  or  even  a dark  loose  granular  powder  if  the  power  is  too  great ; but 
when  properly  produced  it  has  a silky  lustre  or  semi-iridescent  silver-grey  appearance, 
especially  when  viewed  within  the  liquid ; and  if  the  process  is  continued  several  days. 
