Am.  Jour.  Pharm. )     $tate  pharmaceutical  Associations.  539 
:NoYeniber,  1909.  / 
and  retained  in  the  precipitate.  This  "  detannating  "  of  the  gentian 
is  done  so  that  it  may  be  used  in  preparations  containing  iron,  par- 
ticularly with  the  other  gentian  elixirs  of  the  N.F.  containing  iron. 
The  writer  found  that  this  method  is  unnecessary.  By  using  an 
alkaline  citrate  this  tendency  of  iron  salts  to  blacken  when  used  in 
connection  with  gentian  was  avoided.  He  submits  the  following  as 
an  improvement  and  substitute  for  the  present  N.F.  formula : 
Elixir  Gentians. 
Fluidextract  of  gentian   35  c.c. 
Compound  spirit  of  cardamom   15  c.c. 
Sodium  citrate    30  Gm. 
Glycerin    50  c.c. 
Syrup  250  c.c. 
Alcohol    200  c.c. 
Purified  talc    20  Gm. 
Water,  a  sufficient  quantity  to  make  1000  c.c. 
Dissolve  the  sodium  citrate  in  350  c.c.  of  water.  Add  to  this 
solution  the  fluidextract  of  gentian  and  then  the  glycerin.  Mix 
the  compound  solution  of  cardamom  and  the  alcohol,  and  gradually 
add  to  this  the  other  solution,  shaking  well  after  each  addition. 
Then  add  sufficient  water  to  make  the  product  measure  1000  c.c. 
Add  the  talc  and  filter. 
The  author  states  that  by  this  method  elixir  of  gentian  can  be 
easily  and  rapidly  made  and  that  it  is  more  agreeable  in  taste,  with 
all  the  advantages  of  a  "  detannated  "  elixir. — Pa.  Pharm.  Assoc. 
U.S. P.  Exsiccated  Salts  and  Their  Preservation. 
By  Charles  H.  LaWall. 
The  writer  states  that  the  phenomena  of  efflorescence  and  deli- 
quescence are  now  known  to  be  due  to  vapor  tension.  That  certain 
simple  substances,  as  the  alums  for  instance,  have  a  tendency  to 
lose  water  of  crystallization  owing  to  the  high  vapor  tension  of 
the  water  of  crystallization  in  the  alum,  but  when  two  of  these 
isomorphous  alums  are  mixed  they  keep  very  well  by  reason  of 
the  vapor  tension  of  the  water  in  each  having  been  lowered  by  the 
influence  of  the  other  alum  dissolved  in  it.  Therefore  manv  official 
substances,  either  hydrated  or  anhydrous,  are  in  a  constantly  chang- 
ing condition  due  to  the  surrounding  atmospheric  conditions,  and 
in  some  instances,  probably,  to  impurities  which  may  be  present. 
