Am,  Jour.  Pharm 
Jan.,  1879. 
Dialyzed  Iron. 
S 
separated  into  two  portions,  an  upper  transparent  solution  and  a  lower 
one  of  precipitated  oxide  or  oxychloride  of  iron,  which  latter  had  a 
very  light-brown  color. 
Again,  the  precipitate  from  3  fluidounces  of  solution  of  tersulphate 
of  iron  was  slightly  washed  and  dissolved  in  if  fluidounce  solution  of 
chloride  of  iron.  In  about  six  hours  the  solution  was  clear,  and  of  a 
rich  dark  brownish-red  color.  It  measured  8  fluidounces.  This  was 
immediately  placed  in  the  apparatus,  and  dialysis  was  completed  in  1 1 
days.  The  solution  of  dialyzed  iron  measured  19 J  fluidounces,  was 
of  a  clear  dark  brownish-red  color,  without  odor,  and  contained  5  per 
cent,  of  solid  matter.    This  did  not  spoil  with  keeping. 
A  solution  of  moist  magma  of  oxide  of  iron  in  solution  of  chloride 
of  iron,  which  is  not  of  a  syrupy  consistence,  if  kept  for  any  length  of 
time,  undergoes  the  same  change  as  the  jelly  described  above.  In  the 
first  place,  the  dull,  by  reflected  light  opaque  color  is  noticed  in  the 
solution,  and  finally  precipitation  takes  place,  leaving  it  utterly  useless 
for  dialysis. 
As  an  experiment  a  solution,  similar  to  the  one  used  in  the  defective 
apparatus,  which  did  not  contain  the  maximum  quantity  of  water  of 
ammonia,  was  subjected  to  dialysis.  4  fluidounces  of  water  of  ammo- 
nia were  added  to  4  fluidounces  of  solution  of  chloride  of  iron.  When 
the  liquid  had  become  clear,  it  was  put  in  the  dialisator.  In  1 1  days 
dialysis  was  completed.  The  solution  measured  18  fluidounces,  was 
of  a  reddish-brown  color  and  contained  5  per  cent,  of  solid  matter. 
During  the  evaporation  of  small  quantities  of  this  solution^  transparent 
longitudinal  scales  formed  on  the  margin  of  the  liquid,  and  if  the 
evaporating  dish  was  left  undisturbed,  they  gradually  grew  in  length 
towards  the  centre  of  the  dish,  the  ends  at  the  same  time  curling 
towards  the  centre.  This  phenomenon  was  not  noticed  in  solutions  of 
dialyzed  iron  prepared  from  solutions  of  iron  in  which  either  a  magma 
of  oxide  of  iron  or  water  of  ammonia  in  sufficient  quantitv  had  been 
added.  These  when  evaporated  apparently  coagulated,  and  when  not 
disturbed  the  solid  matter  was  found  in  small  brittle  heaps,  with  smaller 
or  larger  free  spaces  intervening,  but  without  the  least  sign  of  any  scaly 
formation.  This  peculiarity  might  be  used  as  a  test  to  ascertain 
whether  iron  solutions  emploved  in  dialysis  had  been  sufficiently  satu- 
rated. 
A  solution  was  next  subjected  to  the   process  to  which  water  of 
