Am.  Jour.  Pharm. ) 
August,  1899.  / 
Aralia  Nudicaulis. 
377 
Found. 
Calculated  for 
c  = 
H  = 
88-22 
11*62 
I. 
88-21 
1 1 70 
11. 
(CioH16)a 
88-23 
11-77 
99-84 
99-91 
iocroo 
Here,  then,  the  oxygen  was  eliminated,  and  the  nature  of  a  terpene 
established  for  the  oil. 
In  order  to  ascertain  the  molecular  weight  a  vapor  density 
determination  after  Victor  Meyer's  method  was  made.  The  amount 
of  oil  under  examination  was  -0269;  anthracene  was  used  in  the 
outer  bath,  as  it  was  necessary  to  obtain  a  temperature  of  over  2700. 
After  volatilizing  the  oil,  a  volume  of  gas  of  6-8  c.c.  was  observed 
at  a  temperature  of  21*5°. 
After  making  the  necessary  corrections  as  to  pressure  and 
temperature,  a  molecular  weight  of  198-36  was  calculated.  Taking 
the  formula  (C10H16)n  and  making  n  =  iy2,i.  e.y  C15H24,  we  have  : 
Ci5  =  15  X  12  =  180 
H24=  24  X  1  =   24 
This  figure  agrees  within  the  limit  of  experimental  error  with  the 
figure  198-36,  so  that  the  nature  of  a  sesquiterpene,  C15H24,  is  estab- 
lished for  this  larger  part  of  the  volatile  oil  of  aralia  nudicaulis. 
The  following  color  tests  were  observed.:  One  drop  of  the  sesqui- 
terpene dissolved  in  5  grammes  of  chloroform  showed,  on  addition  of 
one  drop  of  sulphuric  acid,  a  purple  red  color,  gradually  turning 
darker.  One  drop  dissolved  in  5  grammes  of  glacial  acetic  acid 
showed,  on  addition  of  one  drop  of  sulphuric  acid,  a  light  wine-red 
color,  darkening  on  standing.  In  both  cases  the  darkening  of  the  colors 
was  accelerated  by  addition  of  more  sulphuric  acid  and  on  warming. 
One  part  of  the  terpene  was  dissolved  in  three  parts  of  glacial 
acetic  acid  and  mixed  with  equal  parts  of  glacial  acetic  acid  pre- 
viously saturated  with  dry  hydrochloric  acid.  A  rose  color  was 
observed,  gradually  turning  purple,  and  later,  in  about  ten  minutes, 
a  beautiful  sky-blue.  This  color  remained  permanent.  On  distil- 
ling this  blue  compound  in  vacuo,  a  blue  liquid  passed  over  at  140°^ 
too  small  a  quantity,  however,  to  subject  it  to  further  examinations. 
The  sesquiterpene  was  dissolved  in  three  parts  of  ether  and  dry 
hydrochloric  acid  gas  conducted  into  the  mixture,  which  soon 
turned  purplish-red,  gradually  growing  darker,  almost  black.  The 
Together 
