410         ON  THE  SOLUBILITY  OF  PHOSPHATE  OF  IRON. 
Liquor  Arsenici  et  Hydrargyri  Iodidi. 
In  preparing  this,  we  have  sometimes  had  a  red  instead  of 
pale  straw-colored  product,  this  we  believe  arises  from  free 
iodine  contaminating  the  iodide  of  arsenic  ;  it  can  be  removed  by 
boiling  in  an  evaporating  dish,  but  believe  not  without  loss, 
owing  to  the  volatility  of  the  arsenic  salt. 
Vinum  JEJrgotce 
We  have  prepared  by  first  treating  the  ergot  in  fine  powder 
with  pure  ether,  until  deprived  of  its  fixed  oil,  and  then  after  the 
removal  of  the  absorbed  ether,  by  evaporation,  carefully  dis- 
placing with  Madeira  wine.  The  preparation  has  certainly 
more  taste,  but  we  have  had  no  evidence  that  it  is  therapeu- 
tically improved. 
Tinctura  Myrrhce. 
The  use  of  sand  in  the  manufacture  of  this  preparation  by 
displacement  we  have  found  to  be  entirely  unnecessary,  as  there 
is  sufficient  gum  in  myrrh  to  prevent  the  resin  from  adhering 
and  becoming  clogged.  The  operation  is  also  more  satisfactorily 
conducted. 
"  Thuja." 
SOME  FACTS  IN  RELATION  TO  THE  SOLUBILITY  OF  PHOS- 
PHATE OF  IRON. 
By  John  M.  Maisch. 
Philadelphia,  August  lOih,  1859. 
Editor  of  Amer.  Journ.  Pharm. : 
Dear  Sir, — In  Vol.  xxix.,  page  404,  you  have  given  a 
formula  for  the  preparation  of  a  syrup  of  pyrophosphate  of  iron, 
in  accordance  with  the  recommendation  of  E.  Robiquet,  by  dis- 
solving this  ferruginous  salt  by  means  of  a  solution  of  citrate  of 
ammonia.  I  have  repeatedly  prepared  it  in  the  way  there  indi- 
cated, but  within  a  few  days  I  have  come  to  the  conclusion  that 
the  preparation  of  the  pyrophosphatic  salt  is  entirely  unneces- 
sary for  the  purpose. 
If  a  solution  of  citrate  of  sesquioxide  of  iron  is  mixed  with  an 
alkali,  no  precipitation  takes  place,  since  the  newly  formed 
double  salt  is  easily  soluble  in  water ;  the  same  behaviour  as  the 
alkalies,  has  a  solution  of  pyrophosphate  of  ammonia,  and  also 
