Through  this  inside  compartment  a  contin-
uous supply  of  water  flows,  which  takee  up
the  caustic  alkali  produced  and  is  con-
ducted off  into  collecting  tanks.  The  par-
titions are  open  below,  just  reaching  to
the  surface  of  a  layer  of  mercury  wiich
covers  the  entire  bottom  of  the  tank.  The
alkah  metal  {K  or  Na)  liberated  amalga-
mates at  once  with  the  mercury,  which,
l>iiciank  through  the  rockingof  the  tank  by  means  of

the  cam,  e,  passes  into  the  centre  compart-
the  anode  during  the  passage  of  the  current  to  the  iron  catb-
'■■ —  '"'  K)  of  the  amalgam  is  thereby  liberated,  which,  react-

-"-  '-  sodium  (or  K}  hydroxide  and  hydrogen

"  of  chlorine  gas  is  evolved  which
iddle  (cathode)  chamber


ment,  "'here  it  acts

ode,  c ;  tlie  metallic  sodium  (1

ing  with  the  water  present,  gives

From  thi;  two  end  compartment:

be  further  utilized.    The  lye  obtained  from  the


tiims  .ibout  20  per  cent.  01  caustic  soda  (or  KOH),  which,  wlien  evajxirated   yields
a  product  yg.s  lier  cent.  pure.
Of  the  processes  ot  electrolyzing  a  fused  alkaline  chloride  the  best  known  and
most  suci'essful  is  the  Acker  process  in  use  at  Niagara  Falls.  The  cathode  in  this
case  is  metallic  lead  which  alloys  with  the  metallic  sodium  set  free  in  the  decom-
pisition  of  the  fused  chloride.  This  alloy  of  lead  and  sodium  flows  intoanothcr  cell
where  the  necessary  quantity  of  superheated  steam  acts  upon  it,  forming  anhydrous
sodium  hydroxide  and  liberating  the  molten  lead,  which  again  passes  mto  the  de-
composing cell  to  serve  as  cath<^e.
