500 
{  Am.  Jour.  Pharm^ 
\      Oct.,  1882. 
filtering,  evaporating  nearly  to  dryness  and  then  boiling  with  90" 
per  cent,  alcohol.  From  the  solution,  M^hich  according  to  Wiggers 
contained,  besides  quassiin  and  coloring  matter,  some  sodium  chloride 
and  potassium  nitrate,  the  alcohol  was  distilled  off  and  it  was  then 
evaporated  to  dryness.  The  residue  was  dissolved  in  the  least  possible 
quantity  of  alcohol  and  mixed  with  a  considerable  quantity  of  ether, 
which  separated  much  coloring  matter.  The  filtrate  was  now  again 
evaporated,  and  dissolved  in  absolute  alcohol  and  ether  and  this 
repeated  until  the  residue  was  colorless  and  free  from  saline  matter. 
Lastly  the  etherial  solution  was  poured  into  a  small  quantity  of 
water  and  left  to  evaporate  spontaneously. 
Wiggers  found  for  quassiin  the  formula  Q^o^ifi^-  According  ta 
him  it  loses  1*'>  per  cent,  of  water  at  100°C.,  and  0*37  per  cent,  more 
upon  fusing.  The  melting  point,  he  says,  lies  a  little  above  that  of 
the  resin.  He  found  it  dissolve  in  220  parts  of  water  at  12°C.,  and 
it  did  not  neutralize  acids.  It  crystallized  by  spontaneous  evaporation 
from  a  solution  in  alcohol  and  ether  which  was  mixed  with  water,  and 
also  when  a  warm  saturated  alcoholic  solution  was  mixed  with  boiling 
water  and  allowed  to  cool.  The  quassiin  of  Wiggers  was  precipitated 
by  tannic  acid,  but  not  by  metallic  salts. 
In  commencing  the  present  investigation,  Herr  Christensen  first 
directed  his  attention  to  find  a  new  method  of  preparation,  since  the- 
methods  of  Winckler  and  Wiggers  yielded  it  in  a  very  impure  condi- 
tion and  the  operations  for  its  purification  would  involve  considerable  ' 
loss.  The  author  tried  two  methods  that  are  available  in  the  extrac- 
tion of  several  bitter  substances :  (1)  treatment  of  a  solution  of  the 
watery  extract  with  bone  black  and  exhaustion  of  this  with  alcohol ; 
and  (2)  precipitation  of  the  watery  extract  with  tannic  acid,  decompo- 
sition of  the  washed  precipitate,  extraction  with  alcohol,  etc.  In  both 
cases,  by  evaporating  sloAvly,  he  obtained  tabular  crystals,  having  an 
intensely  bitter  taste,  leaving  on  combustion  no  ash,  difficultly  soluble 
in  water  and  fairly  sohible  in  alcohol.  The  solutions  gave  with  tannic 
acid  a  dense  white  precipitate. 
Notwithstanding  that  the  quassiin  is  tolerably  completely  removed 
by  bone  black,  as  is  shown  by  the  fact  that  the  filtrate  tastes  only 
slightly  bitter,  the  tannic  acid  method  has  the  advantage  that  it  yields 
the  purer  product.  The  following  method  was  adopted  by  the  author 
for  the  preparation  of  quassiin  : 
Five  kilos  of  quassia  were  boiled  several  hours  with  two  successive 
