172  British  Pharmaceutical  Codex.        !  ^m Aprn';  imrm" 
slightly  alkaline,  is  then  divided  into  two  portions,  to  one  of  which 
is  added  a  solution  of  manganous  sulphate,  for  the  purpose  of  ascer- 
taining the  presence  or  absence  of  cinnamic  acid,  Prof.  W.  L. 
Scoville  having  recently  called  attention  to  the  fact  that  benzoic  acid 
does  not  produce  a  precipitate  with  manganous  sulphate,  while 
cinnamic  acid  does.  To  the  other  portion  is  added  solution  of  ferric 
chloride  for  the  purpose  of  confirming  the  presence  of  benzoic  acid. 
The  amount  of  benzoic  acid,  as  determined  by  the  foregoing  proc- 
ess, may  be  calculated  as  sodium  benzoate,  as  it  is  in  this  form 
when  added  to  the  catsup,  and  in  terms  of  which  it  is  stated  on  the 
label. 
This  process  is  applicable,  of  course,  only  where  benzoic  acid  is 
the  sole  preservative  used,  as  salicylic  acid  and  saccharin  are  both 
extracted  by  this  method,  and  unless  tneir  absence  was  assured, 
would  be  estimated  as  benzoic  acid. 
The  principle  upon  which  the  above  process  is  based  is  that  out- 
lined by  Prof.  F.  X.  Moerk  in  the  "  Proceedings  of  the  Pennsyl- 
vania Pharmaceutical  Association  "  for  1 905,  page  181,  in  an  article 
on  the  detection  and  estimation  of  benzoic  acid  and  salicylic  acid  in 
milk,  in  which  he  advocates  the  use  of  sodium  chloride  and  hydro, 
chloric  acid  in  assisting  in  the  extraction  of  these  preservatives  in 
the  pure  state  and  preventing  emulsiflcation  during  the  process. 
SUGGESTIONS  FROM  THE  BRITISH  PHARMACEUTICAL 
CODEX. 
By  M.  I.  Wii^bert, 
Apothecary  at  the  German  Hospital,  Philadelphia,  Pa. 
No  English-speaking  pharmacist  who  is  at  all  interested  in  the 
science  of  his  calling  can  afford  to  ignore  the  British  Pharmaceutical 
Codex,  or  even  attempt  to  conduct  an  up-to-date  pharmacy  without 
a  copy  of  this  really  valuable  compendium. 
Even  a  cursory  inspection  of  this  book  must  suggest  that  it 
promises  to  be  an  active  factor  in  encouraging  rational  prescribing 
on  the  part  of  medical  practitioners,  and  it  will  surely  prove  to  be 
a  powerful  incentive  to  the  development  of  an  active  interest  in  the 
science  of  pharmacy  on  the  part  of  the  votaries  of  that  calling. 
While  the  monographs  and  the  descriptions  of  drugs  and  chemi- 
