166    ON  IDENTITY  OF  PEUCEDANINE  WITH  IMPERATORINE. 
soluble,  but  it  still  retains  a  burning  taste.  The  author  there- 
fore boiled  it  with  thick  milk  of  lime,  when  a  lime-compound  is 
produced,  which  forms  caseous  flakes ;  this  is  decomposed  by 
acetic  acid,  and  the  imperatorine,  which  is  precipitated  in  brown 
flakes,  is  purified  by  recrystallization  from  cold  alcohol.  It  is 
then  perfectly  tasteless. 
The  author  afterwards  gives  the  following  process  of  his  own 
for  the  preparation  of  imperatorine,  by  which  a  greater  propor- 
tion is  obtained.  In  this  way  he  prepares  imperatorine  both  from 
the  root  of  Imperatoria  Ostruthium  and  from  Peucedanum 
officinale.  For  this,  1  kilogrm.  of  finely-cut  air-dried  root  is  ex- 
tracted, in  a  displacement  apparatus,  with  3  litres  of  alcohol  of 
spec.  grav.  0-876,  at  the  ordinary  temperature.  Through  the 
extracted  root  1  more  litre  of  alcohol  is  then  passed ;  and  this 
is  followed  by  a  litre  of  water,  so  as  completely  to  remove  the 
alcohol.  The  extracts  are  mixed  and  evaporated  on  the  water- 
bath,  or  in  a  retort,  at  a  temperature  of  about  140°  F.,  until 
about  1  litre  of  fluid  remains.  The  fluid,  when  left  to  stand, 
separates  into  two  strata, — a  thicker,  pale  brown,  watery  one  at 
the  bottom,  which  has  a  sweet  and  aromatic  taste  ;  and  a  superior 
resinous  one,  of  a  brown  color.  The  latter  is  separated  from  the 
watery  stratum,  and  placed  in  a  broad  porcelain  saucer.  In  a 
few  days  it  becomes  converted  into  a  granular  crystalline  mass, 
which  is  pressed  between  blotting-paper  to  remove  the  fatty  oil, 
which  has  the  greatest  affinity  to  linseed  oil,  acquires  a  yellow 
color  with  potash,  at  the  same  time  evolving  the  characteristic 
odor  of  linseed-oil.  The  granular  mass  thus  obtained  is  purified 
by  treatment  with  milk  of  lime  and  recrystallization  from  cold 
alcohol.  In  this  process  only  a  small  quantity  of  the  fatty  oil  is 
dissolved ;  this  being  a  good  solvent  for  imperatorine,  produces  a 
loss. 
The  watery  fluid  contains  besides  a  great  deal  of  grape-sugar, 
a  small  quantity  of  a  nitrogenous  body,  which  when  heated  with 
potash  evolves  an  odor  like  that  of  coniine. 
The  author  has  compared  the  product  prepared  by  him  with  a 
sample  sent  to  him  by  Prof.  Wackenroder ;  the  differences  which 
occur  in  the  properties  attributed  to  peucedanine  and  impera- 
torine arise  from  adherent  impurities.  The  pure  substance  is 
tasteless.    Prof.  Wackenroder  has  informed  the  author  that  im- 
