32  Leaves  of  Strychnos  Nux-Vomica.  {^'zml'vm*™' 
Five  grams  of  the  powdered  leaves  were  exhausted  with  boiling 
chloroform  and  alcohol  for  one  hour,  using  a  reflux  condenser.  The 
extract  evaporated  to  dryness  was  heated  with  water  acidulated 
with  sulphuric  acid,  and  when  cold  was  filtered  and  the  filter  washed. 
The  light  colored  liquor  was  treated  with  freshly  prepared  Mayer's 
reagent  (i  cc.  indicating  0  0197  gram  of  anhydrous  brucine)  and 
required  0-9  cc.  for  complete  precipitation,  equivalent  to  0-354  per 
cent,  of  brucine. 
The  estimation  was  repeated,  and  exactly  the  same  amount  of 
Mayer's  reagent  was  required  to  precipitate  the  alkaloid  from  the 
acid  solution  obtained  from  5  grams  of  the  leaves.  The  precipitates 
were  collected  on  a  filter,  washed,  dried  and  weighed  together. 
Calculating  from  the  formula  of  the  brucine  iodide  with  mercury 
iodide,  C23H0(5N.,04HI,  Hgl2,  containing  40-37  per  cent,  of  brucine, 
the  united  precipitates  from  the  10  grams  of  leaves  showed  the 
presence  of  0-368  per  cent,  of  alkaloid. 
A  larger  quantity  of  the  leaves  was  worked  up  for  alkaloid,  and 
the  residue,  purified  by  chloroform,  was  converted  into  acid  sul- 
phate, and  its  solution  treated  with  ferrocyanide  of  potassium,  as 
described  in  Messrs.  Dunstan  and  Short's  method  for  separating 
strychnine  and  brucine.  The  very  slight  precipitate  that  fell  was 
not  characteristic  of  strychnine  ferrocyanide,  and  upon  testing  it 
further  with  sulphuric  acid  and  potassium  bichromate,  the  violet 
color  was  not  developed.  A  neutral  solution  of  the  alkaloid  was 
tested  with  potassium  chromate,  but  no  precipitate  appeared  until 
the  liquor  was  concentrated,  and  the  precipitate  gave  no  color  reac- 
tion with  the  oxidizing  mixture.  Wynter  Blyth  considers  potas- 
sium chromate  a  very  delicate  test  for  strychnine.  On  the  other 
hand,  the  alkaloid  obtained  from  the  leaves  responded  to  the  more 
important  reactions  of  brucine.  The  action  of  nitric  acid  was  spe- 
cially studied,  and  among  the  products  were  detected  crystals  of 
kakotelin,  and  the  mother  liquor  contained  oxalic  acid. 
Other  constituents  of  nux-vomica  leaves  are  an  acid  resin  soluble 
in  spirit  and  aqueous  alkalies,  and  dissolved  by  sulphuric  acid  with 
a  green  color  changing  to  reddish-brown,  and  a  caoutchouc-like 
substance  dissolved  by  benzol,  but  not  by  spirit  or  alkalies.  An 
organic  acid,  probably  the  strychnic  or  igasuric  acid  of  older  writers, 
is  associated  with  the  alkaloid  in  both  the  alcoholic  and  aqueous 
extracts.    It  strikes  a  green  color  with  ferric  chloride,  and  is 
