IS 
Syrup  of  Iodide  of  Iron. 
J  Am.  Jour.  Phariru 
t     January,  1901. 
determining  the  possible  formation  of  a  ferric  compound,  gave  a 
negative  result. 
Identical  results  were  obtained  with  a  syrup  containing  10  per 
cent,  of  ferrous  chloride. 
The  influence  o(  temperature  is  demonstrated  by  the  fact  that 
syrups  prepared  by  dissolving  the  sugar  in  the  iron  solution  at  a 
temperature  below  the  boiling  point,  possess  greater  stability  than 
those  heated  to  boiling. 
The  addition  of  hypophosphorous  or  other  acids  exerts  no  influ- 
ence except  to  prevent  the  liberation  of  iodine. 
Several  specimens  of  the  syrup  to  which  hypophosphorous  acid 
was  added,  originally  of  a  bright  green  color,  have  gradually  turned 
brown. 
The  premature  addition  of  an  acid  may  cause  the  syrup  to  rapidly 
change  in  color. 
In  an  instance,  where  this  possibility  was  considered,  the  addition 
of  hypophosphorous  acid  to  a  boiling  bright  green  syrup  was  fol- 
lowed by  an  immediate  change  to  dark  brown. 
This  points  to  the  necessity  of  adding  the  acid  only  to  the  per- 
fectly cold  syrup. 
This  color  change  may  also  be  noticed  if  a  small  quantity  of  the 
syrup,  either  with  or  without  an  addition  of  acid,  be  heated  to  boil- 
ing and  the  heat  continued.  Caramelization  will  be  the  consequence. 
Brief  mention  may  be  made  of  the  restoration  of  discolored 
syrups  of  iodide  of  iron. 
Specimens  containing  free  iodine  may*  be  restored  by  the  well- 
known  practice  of  digestion  with  iron  filings. 
Care  in  the  regulation  of  heat  must  be  observed,  and  addition  of 
a  sufficient  amount  of  water  to  restore  the  original  weight  of  the 
syrup  should  not  be  neglected. 
A  syrup,  in  which  the  brown  color  is  due  to  caramelization,  is 
difficult  of  restoration. 
Animal  charcoal  will  remove  some  of  the  brown  color,  but  the 
writer  has  never  been  able  to  completely  restore  the  original  bright 
green  color  by  this  method.  •  § 
It  may  incidentally  be  mentioned,  that  if  further  investigations 
should  prove  this  action  of  iron  salts  upon  saccharine  solutions  to  be 
true,  the  color  change  in  elixirs  containing  scaled  iron  salts,  which 
is  the  source  of  much  annoyance  to  the  pharmacist,  is  thereby  ex- 
plained. 
