Am.  Jour.  Pharm.  > 
September,  1908.  J 
Natural  Salicylates. 
peppery,  woody  odor,  yet  not  so  sharp  as  the  synthetic  methyl  sali- 
cylate. Methyl  salicylate  has  a  rather  sharp,  even  more  agreeable, 
odor  than  the  others.  The  difference  in  the  odors  can  be  more 
readily  recognized  by  taking  accurately  I  c.  c.  of  each,  and  mixing 
with  separate  portions  of  100  grammes  of  powdered  sugar,  or  by 
dissolving  I  c.c.  in  50  c.c.  of  alcohol  and  pouring  into  I  liter  of 
water.  Another  thing  that  should  be  noted  is  the  relative  turbidity 
of  these  mixtures.  Synthetic  methyl  salicylate  will  usually  become 
clear  before  either  oil  of  birch  or  oil  of  wintergreen.  These  solu- 
tions may  be  diluted  with  a  larger  amount  of  water  and  the  relative 
odor  intensity  of  the  very  dilute  solutions  noted. 
(/)  Cone's  Test.  This  test  is  of  much  value  in  passing  on  the 
quality  of  an  oil.  We  believe  it  is  reliable  within  certain  limits  if 
certain  details  are  very  carefully  complied  with.  The  test  has  been 
published  in  the  American  Journal  of  Pharmacy,  1903,  page  406. 
Two  stock  solutions  are  required : 
Place  6  c.c.  of  the  oil  in  a  500  c.c.  round  bottomed  flask  and  add 
25  c.c.  of  solution  No.  1  and  25  c.c.  of  water.  Boil  till  clear.  Pour 
in  350  c.c.  of  hot  water  and  bring  to  a  boil.  Now  add  25  c.c.  of 
solution  No.  2  and  boil  for  a  few  moments,  then  set  aside  in  a  moder- 
ately warm  place,  so  that  crystallization  will  be  slow. 
A  pure  oil  will  give  the  characteristic  large,  square-ended,  laminar, 
opaque  crystals  which  occupy  comparatively  little  space.  Methyl 
salicylate  under  same  conditions  will  give  fine,  needle-shaped,  vol- 
uminous, opaque,  fluffy  crystals,  which  occupy  nearly  all  of  the 
flask. 
Mixtures  of  the  pure  oil  with  synthetic  methyl  salicylate  give 
gradations  between  these  extremes,  and  by  making  tests  on  admix- 
tures of  known  strength,  crystals  from  a  given  sample  may  be  com- 
pared and  an  intelligent  idea  obtained  of  the  proportion  of  adultera- 
tion. 
Several  trials  should  be  made  with  each  sample.  We  have  found 
that  certain  details  must  be  carefully  watched ;  namely,  having  a 
No.  1. 
Caustic  soda 
Water  q.  s. 
320  c.c. 
4,000  c.c. 
No.  2. 
Hydrochloric  acid 
Water  
1,280  c.c. 
4,000  c.c. 
