3i6 
Syrups. 
/Am.  Jour.  Pharm. 
I       July,  1909. 
glycerin,  orange  flower  water,  and  300  c.c.  of  distilled  water  to 
saturate  and  leave  a  layer  above.  Then  cork  up  the  percolator  and 
cover  and  macerate  for  two  days.  Then  percolate  slowly,  using  the 
remainder  of  the  mixture  and  then  distilled  water  till  700  c.c.  of 
percolate  is  obtained ;  in  this  dissolve  the  sugar,  using  a  water 
bath  heat  if  necessary,  and  strain,  make  up  the  product  to  1000  c.c. 
with  distilled  water. 
Syrupus  Pruni  Virginians  U.S. P. — Each  of  the  writers  has 
independently  made  up  samples  of  this  syrup  by  the  method  of 
U.S. P.,  1890,  and  by  the  present  official  method.  One  has  moist- 
ened the  wild  cherry  and  packed  it  at  once  in  a  percolator  and  then 
added  sufficient  water  to  leave  a  layer  above,  tightly  covered  and 
corked  up  the  percolator,  macerated  for  twenty-four  hours  before 
continuing  the  process.  The  ether  has  followed  the  direction  of  the 
U.S. P.  to  pack  in  percolator  twenty-four  hours  after  moistening. 
Determinations  made  showed  that  the  process  of  U.S. P.,  1890. 
yielded  the  greater  amount  of  astringent  principle,  but  that  the 
syrups  made  U.S. P.,  VIII,  contained  a  greater  percentage  of  hydro- 
cyanic acid,  and  from  this  we  concluded  that  the  presence  of 
glycerin  in  the  menstruum  exerted  an  inhibitive  action  on  its  genera- 
tion. The  experiment  with  immediate  packing  and  a  layer  of  water 
as  above  stated  gave  a  higher  percentage  of  hydrocyanic  acid.  In 
no  case  does  the  amount  of  hydrocyanic  acid  present  in  the  syrup 
compare  favorably  with  that  shown  to  be  present  in  the  bark  by 
direct  distillation  and  determination.  It  is  apparent  that  the  bark 
is  not  entirely  exhausted  and  we  propose  to  make  further  investi- 
gations to  determine  the  percentage  of  such  extraction  and  amount 
left  in  the  marc,  and  at  a  later  date  will  record  the  analytical  data. 
Our  experiments  warrant,  however,  the  following  recommen- 
dations :  That  the  present  official  method  be  modified  to  direct  that 
the  moistened  powder  be  packed  and  macerated  in  the  percolator  for 
twenty-four  hours  with  sufficient  water  to  keep  it  submerged,  and 
that  the  percolation  be  then  continued  until  the  liquid  in  the  re- 
ceiving vessel  containing  the  glycerin  measures  at  least  600  c.c.  It 
is  to  be  noted  in  this  connection  that  in  U.S. P.,  VIII,  an  error  in 
this  formula  has  inadvertently  crept  in.  The  1890  Pharmacopoeia 
percolated  with  a  menstruum  containing  150  c.c.  of  glycerin  until 
450  c.c.  of  percolate  was  obtained.  The  present  official  directions 
are  that  the  percolation  with  water  be  continued  until  the  liquid  in 
the  receiving  bottle  measures  450  c.c.    As  150  c.c.  of  glycerin  is 
