160  Some  Notes  on  Essential  Oils.  {^'Iv^vm^' 
to  compete  with  the  natural  oil.  According  to  one  manufacturer's 
statement  the  cost  of  production  cannot  be  reduced  beyond  a  certain 
limit;  this  is  at  the  present  time  much  beyond  the  price  of  a  good 
natural  product.  The  artificial  oil  does  compete,  however,  to  a  limited 
extent,  with  Ceylon  oil  of  cinnamon,  the  constant  composition,  light 
color  and  sweet  delicate  flavor  making  it  if  anything  superior  to  the 
best  Chinese  oil. 
In  this  connection  it  would  appear  feasible  to  obtain  absolute,  or 
nearly  absolute,  cinnamic  aldehyde,  and  if,  as  has  been  asserted,  this  is 
the  active  ingredient  of  the  commercial  oil,  there  could  be  but  little 
objection  to  its  introduction  in  medicine. 
It  might  be  mentioned  here  that,  owing  no  doubt  to  the  very 
low  price  of  oil  of  cinnamon,  or  rather  oil  of  cassia,  little  or  no  com- 
plaint is  being  made  of  any  wholesale  adulteration. 
Oil  of  Cloves. — Schimmel  &  Co.  say  that  the  market  in  this  oil 
must  be  considered  to  be  in  a  demoralized  condition ;  only  experts 
could  estimate  the  real  value  of  any  of  the  present  oils. 
Ten  samples  of  oil  of  cloves,  examined  by  Schimmel  &  Co.  re- 
cently, varied  in  specific  gravity  from  1-0287  to  1-066,  and  in  phenol 
content  from  73  to  98-75  per  cent. 
Gildemeister  and  Hoffmann  give  the  specific  gravity  of  a  true  oil 
of  cloves  as  varying  from  1*045  to  I,075»  according  to  the  method 
of  preparation.  The  eugenol  content  varies  from  70  to  85  per  cent. 
According  to  Kremers  [Phar.  Rev.,  1902,  page  499)  some  manufac- 
turers collect  the  distillate  from  cloves  in  fractions.  From  these 
fractions  a  mixture  is  made  to  conform  to  the  desired  U.S.P.  article 
for  medicinal  use.  The  latter  takes  but  a  comparatively  unimpor- 
tant portion  of  the  total  oil  produced. 
Professor  Kremers,  at  the  last  meeting  of  the  American  Pharma- 
ceutical Association,  called  attention  to  the  wide  variation  in  the 
specific  gravity  of  an  oil  of  cloves,  the  total  product  of  distillation. 
Kremers  pointed  out  that  if  the  U.S.P.  intended  to  include  the  total 
product,  greater  variation  in  the  permissible  specific  gravity  were 
necessary. 
In  addition  to  eugenol,  oil  of  cloves  has  a  number  of  constituents, 
among  them  a  small  quantity  of  methyl  alcohol,  about  3  per  cent, 
of  acet  eugenol,  a  sesqui-terpene  (caryophyllin),  acet  salicylic  acid, 
ester  of  eugenol,  methylamylketone,  vanillin  and  furfurol.  It  is  to 
the  latter  of  these  compounds  that  the  gradual  darkening  of  oil  of 
