^°*Nov.%888^'^°^*}    Permanent  Syrup  of  Ferrous  Iodide.  547 
PEEMANENT  SYEUP  OF  FEEEOUS  IODIDE. 
By  Joseph  England,  Ph.  G. 
Read  at  the  Pharmaceutical  Meeting,  October  16. 
Within  the  ever  widening  circle  of  modern  pharmaceutical  thought, 
there  is  probably  no  preparation  in  galenical  pharmacy  which  from 
universal  use  and  high  medicinal  value  has  been  so  fertile  in  criticisms 
and  papers  as  syrup  of  iodide  of  iron.  It  would  be  trite  and  of  little 
value  for  the  writer  to  traverse  ground  so  thoroughly  familiar  to  you 
all,  had  he  not  secured  what,  in  his  opinion,  was  a  perfectly  practica- 
ble method  of  preserving  this  easily  oxidizable  liquid ;  a  method 
against  which  there  could  be  raised  not  the  slightest  objection  on  the 
score  of  chemical  incompatibility  or  the  introductioon  of  objectionable 
compounds,  and  in  favor  of  which,  in  this  instance,  everything  could  be 
fairly  claimed  as  an  ideal  preservative. 
Some  months  ago  attention  was  attracted  by  the  strong  reducing 
action  exercised  by  glucose  upon  ferric  salts.  If  ferric  salts,  in  aque- 
ous solution,  be  slightly  heated  with  glucose,  especially  syrupy  glu- 
cose, they  are  quickly  reduced  to  the  ferrous  state.  A  well  known 
pharmacist  of  this  city  states  that  he  has  observed  that  pills  of  cal- 
omel, made  with  glucose,  as  an  excipient,  become  reduced  to  black 
mercurous  oxide.  This  property  of  reduction  possessed  by  glucose,  is 
a  powerful  and  characteristic  one,  and  is  the  one  utilized  in  its  quan- 
titative estimation. 
Such  being  the  case,  what  is  more  reasonable  than  to  assume  that  if 
it  is  opposed  to  oxidation  so  strongly,  it  would  serve  to  protect  easily 
oxidizable  substances  from  oxidation,  and  practice  bears  out  the  truth 
that  theory  teaches.  We  have  a  familiar  illustration  of  this  ap- 
plication of  glucose,  although  it  is  not  generally  recognized  as  such, 
in  the  preserving  of  ^^Vallet's  Mass''  with  honey,  and  yet  what 
ferrous  compound  is  more  prone  to  oxidation  than  ferrous  car- 
bonate ? 
Acting  upon  this  idea,  the  writer  made,  early  in  last  July,  different 
specimens  of  ferrous  iodide  syrup,  and  first  utilized,  as  more  con- 
venient, the  commercial  syrupy  glucose;  a  mixture  of  glucose  and 
dextrin.  But  this  was  found  to  be  too  powerful  in  its  action.  A 
large  quantity  caused  the  precipitation  of  ferrous  oxide,  and  a  small 
quantity  permitted  both  oxidation  and  precipitation.  Eecourse  was 
then  had  to  solid  glucose  (CgHi206),  and  this  was  found  to  be  less  re- 
