AmMi?ch,i902.rm"}    Recent  Literature  Relating  to  Pharmacy.  143 
bitter  and  persistent.  Specific  gravity,  0-925-0-955.  On  account 
of  its  dark  color  it  is  difficult  to  determine  the  optical  rotation  gen- 
erally. The  oil  itself  is  soluble  to  a  clear  solution  in  from  two  to 
four  volumes  of  80  per  cent,  alcohol.  On  submitting  the  oil  to  frac- 
tional distillation  the  first  10  per  cent,  of  the  distillate  is  soluble  in 
two  volumes  of  80  per  cent,  alcohol.  From  the  above  data  it  can 
readily  be  seen  that  numbers  1,  2,  4  and  8  are  deficient  in  a  number 
of  points,  and  careful  investigation  showed  that  these  oils  were  liber- 
ally adulterated  with  oil  of  turpentine.  The  turpentine  odor  was 
even  perceptible  to  the  nose  in  several  samples. 
Laboratory  of  Smith,  Kline  &  French  Co. 
Philadelphia. 
RECENT  LITERATURE  RELATING  TO  PHARMACY. 
estimation  of  phenols,  with  special  reference  to  oil  of  cloves. 
Verley  and  Bolsing  publish  a  paper  [Berichte,  1901,  3354)  on  the 
determination  of  alcohols  and  phenols,  especially  in  essential  oils, 
by  a  method  they  have  elaborated.  In  a  second  paper  they  deal 
with  the  special  applicability  of  the  process  to  oil  of  cloves  for  the 
determination  of  the  eugenol.  The  principle  of  the  process  is  the 
esterification  of  the  alcohol  of  phenol  with  acetic  anhydride,  with 
the  addition  of  pyridine,  which  serves  to  retain  the  acetic  acid 
formed  during  the  esterification,  thus  preventing  the  reverse  process 
of  hydrolysis  going  on.  The  actual  details  of  the  process  are  as 
follows : — 
One  hundred  and  twenty  grammes  of  acetic  anhydride  and  880 
grammes  of  pyridine  are  mixed,  care  being  taken  that  no  traces  of 
water  are  present.  No  reaction  takes  place,  but  on  the  addition  of 
water  the  anhydride  is  decomposed  with  the  formation  of  pyridine 
acetate,  which  is  easily  saponified  by  alkali.  The  acetic  value  can 
thus  be  obtained  for  the  mixtures.  From  1  to  2  grammes  of  the 
substance  to  be  examined  is  introduced  into  a  flask  holding  about 
200  c.c.,  and  25  c.c.  of  the  mixture  of  acetic  anhydride  and  pyridine 
is  added.  It  is  then  heated  for  fifteen  minutes  on  a  water-bath  with- 
out a  condenser,  which  appears  to  be  unnecessary,  and  after  cooling 
25  c.c.  of  water  is  added,  and  the  free  acetic  acid  titrated  with  potash, 
using  phenolphtalein  as  indicator. 
A  number  of  results  are  given,  some  being  of  almost  theoretical 
