402 
GLEANINGS — PHARMACEUTICAL,  ETC. 
However,  such  a  mixture  contains  too  large  a  proportion  of 
pyrophosphate  of  soda,  which  gives  it  a  disagreeable  saline  taste, 
and  does  not  prevent  it,  after  a  larger  or  shorter  interval,  from 
blackening  on  exposure  to  the  air,  and  acquiring  a  more  and 
more  decided  metallic  taste.  It  was,  therefore,  necessary  to 
seek  for  another  solvent.  That  which  I  have  found  to  succeed 
best  is  the  citrate  of  ammonia,  a  salt  which  has  the  double 
advantage  of  being  capable  of  employment  in  very  small  quan- 
tity, and  of  chemically  concealing  iron  from  reagents." 
"  The  solution  of  pyrophosphate  of  iron  in  a  citro-ammon- 
iacal  liquor  keeps  for  whole  months  without  undergoing  any 
change,  and  yields  a  syrup  free  from  the  intolerable  taste  of 
ferruginous  compounds.  Potash,  ammonia,  and  the  alkaline  car- 
bonates do  not  give  with  pyrophosphate  of  iron,  so  dissolved,  the 
reaction  peculiar  to  the  salt  of  iron." 
M.  Kobiquet  further  observes,  "  the  latent  state  in  which  it 
exists  in  this  new  salt,  enables  us  to  mix  it  with  wine  of  bark, 
and  to  obtain  from  it  a  powerful  tonic,  without  having  to  fear 
the  blackish  discoloration  and  inky  taste,  which  are  always  pro- 
duced when  a  salt  of  iron  is  brought  into  contact  with  fluids 
more  or  less  highly  charged  with  tannin." 
"  In  whatever  mode  the  citro-ammoniacal  pyrophosphate  of 
iron  be  administered,  it  has  absolutely  no  taste,  and  patients  not 
only  bear  it  readily,  but  feel  the  best  effects  from  its  use.  I  have 
seen  it  particularly  useful  in  well  marked  cases  of  anemia, 
chlorosis,  and  chronic  urethritis." 
M.  Robiquet  says,  that  dry  pyrophosphate  of  iron  contains 
21.11  per  cent,  of  iron,  that  its  therapeutic  qualities  entitle  it 
to  the  first  rank  among  ferruginous  compounds,  and  gives  the 
following  formula  for  preparing  the  syrup,  viz. : 
SYRUP  OP  PYROPHOSPHATE  OF  IRON.* 
"Take  of  Pyrophosphate  of  iron  two  drachms  and  a  half; 
Simple  Syrup  twenty-nine  ounces  ; 
Syrup  of  Orange  flowers  three  ounces ; 
make  a  syrup  by  simple  solution,  and  color  with  a  sufficient  quan- 
tity of  tincture  of  cochineal  or  alkanet.    Each  drachm  of  the 
syrup  contains  about  six  tenths  of  a  grain,  and  a  tablespoonful 
about  three  grains  of  the  salt  of  iron." 
*  See  page  404. 
