EXTRACTUM  PRUNI  VIRGINIANS  FLUIDUM. 
23 
Thus  made,  fluid  extract  of  wild  cherry  bark  is  a  dark,  wine- 
red,  transparent  liquid,  not  syrupy  in  consistence,  and  possessed 
of  a  bitter,  hydrocyanic  taste.  None  of  the  oil  of  the  almonds 
is  retained,  and  probably  very  little  if  any  of  the  emulsin,  as  it 
may  be  freely  mixed  with  alcohol  without  precipitation. 
As  it  is  not  certain  that  the  preparation  made  with  lactine 
will  keep  even  with  the  assistance  of  the  hydrocyanic  acid,  it 
is  thought  best  to  give  another  formula  in  which  ordinary  sugar 
is  the  preservative  agent  should  it  not  prove  sufficiently  permanent. 
The  extract  may  be  made  with  sugar,  so  as  to  have  the  con- 
sistence of  the  ordinary  syrup,  and  the  same  strength  as  the  above, 
by  using  but  one  pint  of  water  for  the  almond  emulsion,  and 
stopping  the  washing  of  the  dregs  when  a  pint  and  a  half  of 
liquid  has  passed  the  filter,  and  dissolving  in  it  three  and  a  half 
pounds  (troy,)  of  sugar.  Made  with  sugar,  the  great  bitterness 
of  the  preparation  is  masked  by  that  substance,  and  it  is  more 
palatable  than  that  made  with  sugar  of  milk.  When  the  tonic 
properties  of  the  drug  are  mainly  sought,  an  admirable  wine  of 
ivild  cherry  bark  may  be  obtained  by  substituting  half  a  pint  of 
deodorized  alcohol  (88°)  for  the  sugar  of  milk  in  the  first  formula. 
Should  it  be  desirable,  the  preparation  may  be  made  of  double 
the  strength  indicated  above,  by  using  half  the  above  proportion 
of  water  in  making  the  almond  emulsion,  and  half  the  amount  of 
milk  sugar,  so  that  the  whole  shall  measure  a  pint  and  a  half,  yet  it 
is  believed  that  the  strength  adopted  above  is  fully  adequate  to 
the  wants  of  the"physician,  the  thorough  decomposition  of  the 
amygdaline  is  rendered  more  certain  by  the  larger  proportion  of 
water,  which  also  more  effectually  retains  the  volatile  oil  in  solu- 
tion. When  the  almond  emulsion  is  added  to  the  solution  of  ex- 
tract of  cherry  bark,  a  coagulation  occurs  from  the  formation  of 
an  albuminous  tannate,  and  probably  a  portion  of  the  tannin  is 
removed  from  solution,  yet  this  reaction  while  it  does  not  pre- 
vent the  agency  of  the  emulsin  in  decomposing  the  amygdalin, 
and  in  no  wise  effects  the  bitter  tonic  principle,  makes  the  prepara- 
tion less  astringent,  and  less  liable  to  produce  costiveness  by  con- 
tinued use.  If  it  should  be  desirable  to  make  a  preparation  free 
from  astringency,  it  can  be  readily  accomplished  by  macerating 
in  the  aqueous  solution  of  the  alcoholic  extract  of  the  bark  some 
strips  of  isinglass,  previously  softened  in  water,  which  will  re- 
move the  tannin. 
