548 
ON  CYTISINA, 
pletely  with  soda.  The  concentrated  liquid  is  now  precipitated 
with  tannin  with  the  precaution  of  keeping  it  neutral  or  faintly 
alkaline  by  the  addition  of  soda,  the  precipitate  is  rapidly  washed 
with  water,  pressed,  then  dissolved  in  water,  again  precipitated 
by  subacetate  of  lead,  the  lead  removed  by  sulphuric  acid,  the 
liquid  concentrated,  rendered  alkaline  by  soda  and  precipitated 
by  tannin.  The  filtrate  is  again  treated  the  same  way  ;  the 
precipitates  are  decomposed  by  oxide  of  lead,  the  mixture  ex- 
siccated and  exhausted  with  85  per  cent,  alcohol.  The  residue 
after  the  evaporation  of  the  alcohol  is  acidulated  vfith  nitric 
acid,  treated  with  6  or  8  volumes  of  absolute  alcohol  and  the 
solution  decanted  from  a  resinous  mass,  when  it  separates  crys- 
tals of  nitrate  of  cy tisina.  This  salt  is  not  completely  decom- 
posed by  oxide  of  lead  or  baryta  ;  on  boiling  with  concentrated 
potassa  solution,  the  alkaloid  separates  as  an  oil  which  solidifies 
on  cooling.  After  washing  with  little  water,  it  is  kept  in  an 
atmosphere  of  carbonic  acid  to  convert  the  adhering  potassa  into 
carbonate,  and  then  crystallized  from  absolute  alcohol.  . 
Cytisina  G^'FL^'j^fi^  foi'i^is  white  radiating  crystals  of  a  bitter- 
ish, faintly  alkaline  taste,  sublimable  on  careful  heating,  par- 
ticularly in  a  current  of  hydrogen,  in  long  needles  and  plates, 
fusible  at  about  154 -5° C,  very  freely  soluble  in  water  and  al- 
cohol, little  or  not  in  ether,  chloroform,  benzol  and  bisulphide 
of  carbon.  It  is  one  of  the  strongest  vegetable  bases,  and  pre- 
cipitates not  only  the  earths  and  oxides  of  the  heavy  metals,  but 
it  liberates  also  in  the  cold  ammonia  from  its  salts  ;  it  does  not 
dissolve  those  oxides,  and  if  present  m  excess,  prevents  the  re- 
duction of  oxide  of  copper  by  grape-sugar. 
The  nitrate  C4oH27N302i2NHOg  4-4HO  is  the  only  salt  which 
crystallizes  readily;  upon  the  slide  under  the  microscope  it 
forms  crystallizations  resembling  fir-branches ;  it  has  an  acid  re- 
action and  is  sparingly  soluble  in  absolute  alcohol,  freely  in  water 
and  diluted  alcohol,  insoluble  in  ether. 
Corrosive  sublimate  yields  with  the  alkaloid  a  precipitate  of  a 
double  salt.  The  chlorides  of  platinum  and  of  gold,  iodohydrar- 
gyrate  of  potassium,  potassio-iodide  of  cadmium,  biniodide  of 
potassium  and  picric  acid  produce  with  dilute  solutions  of  the 
salts  crystallizable  precipitates.     Bromine  water  yields  with 
