Am.  Jour.  Pharm.  \ 
Feb.,  1878.  / 
Analyses  of  Dialyzed  Iron. 
purity  and  general  superiority  over  the  other  iron  compounds.  Fearing 
that  the  strength  of  the  solution  might  be  sacrificed  somewhat  in  attain- 
ing the  much-desired  elegance,  I  procured  of  the  leading  manufacturers 
of  Philadelphia  six  samples,  and  estimated  the  iron  and  chlorine  by  the 
following  process. 
About  five  grams  of  the  solution  were  taken,  diluted  with  waterT. 
treated  with  ammonic  hydrate  and  heated  gently  until  all  the  iron  was 
precipitated.  This  was  then  filtered  off,  washed  thoroughly,  ignited,, 
and  weighed  as  Fe203.  The  filtrate  and  washings  were  heated  to 
expel  excess  of  ammonia,  and  treated  with  hydric  and  argentic  nitrates. 
The  mixture  was  heated  and  agitated  until  the  resulting  argentic  chlo- 
ride cohered,  then  filtered  and  the  collected  precipitate  washed,  ignited 
and  weighed  as  AgCl,  from  which  the  percentage  of  chlorine  was. 
calculated. 
The  following  table,  containing  a  summary  of  the  analyses,  explains 
itself : 
Per  cent. 
Fe203. 
Per  cent. 
CI. 
Per  cent,  of 
the  salt. 
Formula. 
I. 
3'J43 
•140 
3-192 
29Fe203.Fe2Cl6. 
II. 
3 '442 
•i54 
3"497 
29Fe203.Fe2Cl6. 
III. 
2*394 
•156 
2-514 
i9Fe203.Fe2Cl6. 
IV. 
2-583 
•286 
2  804 
nFe203.Fe2Cl6. 
V. 
4  677 
•198 
4-831 
3iFe203.Fe2Cl6. 
VI. 
2-874 
•235 
3-058 
i6Fe20.3Fe2Cl6. 
There  would  be  no  criticism  to  offer  on  these  results,  were  it  not 
for  the  fact  that  the  circulars  of  these  manufacturers  state  that  the  solu- 
tions contain  five  per  cent,  of  ferric  oxychloride,  or,  as  one  asserts,  of 
ferric  oxide  free  from  hydric  chloride,  both  of  which  statements  are 
incorrect,  and  as  yet  the  latter  has  proved  impossible. 
Finally,  we  see  that  only  the  manufacturers  are  at  fault,  and  that  a 
solution  of  dialyzed  iron  can  be  and  is  prepared,  which,  compared  with 
the  iron,  contains  a  much  smaller  proportion  of  chlorine  than  has  here- 
tofore been  supposed,  three  of  the  samples  showing  this,  the  only 
objection  to  them  being  that  they  contain  too  large  a  percentage  of 
water. 
