DEPORTMENT  OF  ALKALOIDS  WITH  REAGENTS,  ETC.  549 
the  reaction  or  impair  its  delicacy.  It  is  therefore  always 
advisable  to  free  the  strychnia  first,  as  far  as  practicable,  from 
all  foreign  matters  before  proceeding  to  try  this  reaction.  If 
the  solution  colored  red  (by  binoxide  of  manganese)  is  mixed 
with  from  four  to  six  times  its  volume  of  water,  and  ammonia  is 
then  added  until  the  reaction  is  nearly  neutral,  the  fluid  shows 
a  magnificent  violet-purple  tint ;  upon  addition  of  more  ammonia 
the  color  becomes  yellowish-green  to  yellow,  (J.  Erdmann.)  I 
have  found,  however,  that  this  reaction  is  seen  only  where 
larger,  though  still  very  minute,  quantities  of  strychnia  are 
present. 
9.  Strong  chlorine  water  produces  in  solutions  of  salts  of 
strychnia  a  white  precipitate,  which  dissolves  in  ammonia  to  a 
colorless  fluid. 
10.  Concentrated  nitric  acid  dissolves  strychnia  and  its  salts 
to  a  colorless  fluid,  which  turns  yellow  upon  the  application  of 
heat. 
+ 
b.  Brucia,  or  Brucine  (C46  H26  N2  08  =  Br.) 
+ 
1.  Crystallized  brucia  (Br.  +  8  aq.)  appears  either  in  the  form 
of  transparent  right  rhombic  prisms,  or  in  that  of  crystalline 
needles  aggregated  into  stars,  or  as  a  white  powder  composed  of 
minute  crystalline  scales.  Brucia  is  difficultly  soluble  in  cold, 
but  somewhat  more  readily  in  hot  water.  It  dissolves  freely  in 
alcohol,  both  in  absolute  and  dilute,  also  in  cold,  but  more 
readily  still  in  hot,  amyl-alcohol ;  but  it  is  almost  insoluble  in 
ether.  Its  taste  is  intensely  bitter.  When  heated,  it  fuses 
with  loss  of  its  water  of  crystallization. 
2.  Brucia  neutralizes  acids  completely.  The  salts  of  brucia 
are  readily  soluble  in  water,  and  of  an  intensely  bitter  taste. 
Most  of  them  are  crystallizable. 
3.  Potassa  and  carbonate  of  soda  throw  down  from  solutions 
of  salts  of  brucia  a  white  precipitate  of  brucia,  which  is  insoluble 
in  an  excess  of  the  precipitant.  Viewed  under  the  microscope, 
immediately  after  precipitation,  it  appears  to  consist  of  very 
minute  grains ;  but  upon  further  inspection,  these  grains  are 
seen — with  absorption  of  water — to  suddenly  form  into  needles, 
which  latter  subsequently  arrange  themselves  without  exception 
