PECULIAR  ACRID  PRINCIPLE  OF  TRLLIACEiE. 
513 
The  root,  in  coarse  powder,  was  treated  with  alcohol  in  a  dis- 
placer  and  thevtincture  evaporated,  and  water  added  as  the  alco- 
hol distilled  awaj.  Upon  cooling,  a  very  fluid  oleo-resin  was  found 
floating  upon  the  top  of  the  watery  portion,  of  a  light  brown 
color,  possessing  all  the  peculiar  oil-like  odor  of  the  root,  but 
not  the  acrid  taste.  This  was  separated  from  the  watery  portion 
by  a  separating  funnel. 
The  watery  portion  was  acrid  to  the  taste  ;  to  it  both  acetate 
and  sub-acetate  of  lead  was  added  as  long  as  a  precipitate  "was 
produced,  then  filtered  from  the  lead  precipitate,  and  the  excess 
of  lead  removed  by  the  careful  addition  of  sulph.  acid. 
I  was  surprised  to  find,  upon  tasting  the  clear  filtrate,  that 
its  acrid  taste  had  not  been  in  the  least  diminished  by  the  ad- 
dition of  the  lead  salts,  and  satisfying  me  that  the  acrid  princi- 
pl3  was  a  v,ery  different  substance  from  that  of  senega.  This 
filtrate  was  then  set  aside  until  next  day,  for  farther  examina- 
tion. Upon  looking  at  it  next  day,  I  observed  that  a  gelatinous 
precipitate  had  formed,  and  that  the  supernatant  fluid  had  en- 
tirely lost  its  previous  acrid  taste.  The  precipitate  was  collect- 
ed upon  a  filter  and  washed  with  water  ;  this  was  troublesome, 
from  the  nature  of  the  precipitate,  and  had  to  be  very  cautious- 
ly done,  as  I  found  that  it  was  again  taken  up  by  the  wash  water. 
It  was  then  allowed  to  become  almost  dry  upon  the  filter,  then 
detached  from  it,  re-dissolved  in  dilute  alcohol  and  left  to  spon- 
taneous evaporation.  It  dried  to  a  white,  amorphous  mass, 
easily  powdered,  and  had  all  the  acrid  taste  of  the  root  in  a  con- 
centrated degree.  I  subsequently  tried  its  solubility  in  alcohol ; 
it  dissolved  completely,  and  was  then  evaporated  to  a  certain  ex- 
tent, spread  out  with  a  brush  on  glass,  which,  upon  drying,  was 
easily  detached  in  glistening  scales.  This  substance,  like  saponin 
and  senegin,  has  the  peculiar  property  of  forming  with  water 
frothing  soap-like  mixtures.  Half  a  grain  of  this  to  two  ounces 
of  water,  is  sufficient  to  develope  this  peculiarity,  and  the  foam 
formed  upon  the  water  will  remain  unbroken  for  several  days. 
To  ascertain  whether  this  substance  was  the  result  of  oxida- 
tion of  the  oil  obtained  in  the  first  treatment,  it  was  submitted  to 
oxidizing  operations.  A  portion  of  the  oil  assumed  a  changed 
appearance  by  the  treatment ;  became  a  white  substance,  which 
33 
