ABnAp°ri[:ifob3arir'}       Some  Notes  on  Essential  Oils.  155 
One  has  only  to  look  back  a  few  years  and  note  how  the  demand 
for  the  rank  ether-composed  fruit-flavors  has  almost  disappeared  to 
see  that  the  popular  standard  for  flavors  is  and  must  be  a  variable 
one,  and  can  be  relied  upon  to  regulate  itself  in  accordance  with 
the  progress  of  art  and  science  in  improving  upon  the  old  and  the 
better  opportunities  for  better  foods  and  cooking  in  general. 
Boston,  Mass.,  March  1,  1903. 
SOME  NOTES  ON  ESSENTIAL  OILS. 
By  M.  I.  Wii^ERT, 
Apothecary  at  the  German  Hospital,  Philadelphia. 
Among  the  various  substances  official  in  our  national  pharmaco- 
poeia, few  have  attracted  more  attention,  as  a  class  particularly,  than 
have  the  essential  oils.  Volumes  have  been  written  on  the  subject, 
and  years  of  patient  work  and  study  on  the  part  of  a  small  army  of 
investigators  have  been  spent  in  studying  the  physical  properties 
and  determining  the  chemical  composition  of  the  different  com- 
pounds usually  classed  under  this  head. 
From  the  point  of  view  of  the  practical  pharmacist,  essential  oils 
are  of  interest  in  that  with  them,  more  than  with  any  other  class  of 
compounds,  he  is  largely  it  not  entirely  at  the  mercy  of  the  dealer 
or  manufacturer. 
It  is  true  that  the  pharmacopoeia  gives  descriptions  of  the  physi- 
cal properties,  and  usually  also  chemical  tests,  for  the  identification 
of  the  different  oils,  but  even  then  it  is  quite  possible  for  almost 
any  one  of  these  oils  to  conform  to  a  number  of  the  pharmacopoeiai 
requirements  and  still  be  adulterated  or  debased  to  a  very  consider- 
able degree. 
To  be  positive  of  the  genuineness  or  purity  of  almost  any  one  of 
the  essential  oils,  it  would  be  necessary  that  the  pharmacist  be  a 
specialist  in  this  particular  branch  of  chemistry,  and  have  at  his 
command  intricate  and  expensive  pieces  of  apparatus  for  determining 
the  specific  gravity,  boiling-point,  congealing-point,  optical  rotation 
and  refraction  of  an  oil,  to  say  nothing  of  fractional  distillation  or 
the  chemical  determination  of  the  different  constituents  by  means  of 
saponification,  esterification,  acetylization  or  any  one  of  the  other 
procedures  that  have  been  devised  for  separating,  or  recognizing  the 
nature  of,  the  various  compounds  of  which  the  essential  oils  are 
composed. 
