Am.  Jour.  Pharm 
Oct.,  1892. 
Examination  of  Eugenol. 
through  a  filter,  previously  dried  at  ioi°  C.  and  weighed,  and  the 
operation  of  washing  the  crystals  is  repeated  twice  with  50  cc.  of  water. 
To  remove  the  sesquiterpene,  contaminating  the  benzoyl-eugenol, 
the  crystals  are  washed  with  alcohol  by  adding  to  the  still  moist 
mass  in  the  beaker  25  cc.  alcohol  of  90  per  cent.,  warming  until 
solution  is  effected,  and  then  rotating  the  liquid  until  crystals  begin 
to  separate,  when  the  contents  of  the  beaker  are  allowed  to  cool  to 
170  C,  transferred  to  the  weighed  filter  and  washed  with  a  little  90 
per  cent,  alcohol  until  the  filtrate  measures  25  cc;  the  filter  and 
contents  are  now  transferred  to  the  beaker,  dried  at  1010  C.  and 
weighed.  To  the  weight  of  the  benzoyl-eugenol  thus  obtained, 
0-550  gm.  must  be  added,  representing  the  amount  soluble  in  the 
25  cc.  of  90  per  cent,  alcohol.  This  weight,  multiplied  by  164  (the 
molecular  weight  of  eugenol)  and  divided  by  268  (the  molecular 
weight  of  benzoyl-eugenol)  gives  the  amount  of  eugenol  in  5  gm. 
of  the  oil ;  to  obtain  the  percentage,  multiply  again  by  20. 
In  performing  the  experiment,  the  author  suggests  to  pour  into 
the  tared  beaker  containing  the  oil,  simultaneously  from  two  sepa- 
rate vessels,  the  sodium  hydrate  and  benzoyl-chloride,  and  then  stir 
with  a  glass  rod.    The  results  obtained  were  as  follows : 
Specific  Eugenol. 
Gravity.  Per  Cent. 
(1)  Oil  of  cloves,  distilled  by  author,    ...  *  1*0675  77*96 
(2)  commercial,   1*0514  78*74 
(3)  "                  "           ........  1-0502  75-08 
(4)  "                  "   •  1*0483  72*26 
(5)  "                  "  .    1*0490  74-22 
(6)  "  old,  distilled  by  Professor 
Remington,    1*0752  75-74 
(7)  •"  clove  stems,  distilled  by  author,   .  1*0552  87-10 
(8)  "     "     commercial,   1*0441  80*34 
(9)  "  '               "    i'°452  7778 
These  results  agree  with  the  observation  of  Dr.  Thorns  that  the 
specific  gravity  has  no  uniform  relation  to  the  percentage  of  eugenol 
present,  and  that,  besides  the  eugenol  and  terpene,  probably  a  third 
compound  is  present  in  the  oil  which  may  account  for  the  variation. 
It  will  be  observed  that  all  the  commercial  samples  are  rich  in 
eugenol,  also  that  the  oil  of  clove  stems,  although  not  so  fragrant, 
shows  a  rather  larger  percentage  of  eugenol. 
Note  by  the  Editor. — According  to  the  semi-annual  report  of 
Schimmel  &  Co.  (April,  1892,  p.  20),  the  method  yields  concordant 
