326 
ON  DAPHNINE. 
the  aqueous  liquid,  freshly  precipitated  hydrated  oxide  of  lead 
removes,  on  continued  boiling,  the  daphnine  ;  if  this  precipitate 
is  decomposed  by  sulphuretted  hydrogen,  the  filtrate  evaporated 
and  the  residue  redissolved  in  little  boiling  alcohol,  daphnine 
will  crystallize  on  spontaneous  evaporation.  The  first  process, 
however,  is  preferable. 
In  preparing  the  extr.  mezerei  asthereum  of  some  Pharmaco- 
poeias, all  the  daphnine  may  be  obtained  from  the  residue,  left 
by  treating  the  alcoholic  extract  with  ether. 
Daphnine  is  insoluble  in  ether,  little  soluble  in  cold  water, 
freely  in  hot  water  and  alcohol,  particularly  in  boiling  alcohol  ; 
on  cooling  it  separates  in  silky  needles  or  in  colorless  rectangu- 
lar prisms.  It  has  an  acid  reaction,  and  a  bitterish,  astringent 
taste  ;  at  100"^  C,  (212^  F.),  it  loses  9-3  per  cent,  water  of 
crystallization,  has,  at  a  somewhat  higher  heat,  a  faint  odor, 
reminding  of  coumarin,  fuses  at  about  200^  C,  (392^  F.),  and 
is  decomposed,  finally  giving  off  tbe  odor  of  burning  sugar.  It 
is  soluble  in  alkalies  and  their  carbonates  ;  the  golden  yellow 
solution  becomes  brown  red  by  exposure  and  boiling.  Its  solu- 
tion is  not  precipitated  by  acetate  of  lead,  is  colored  and,  on 
boiling,  precipitated  yellowish  by  subacetate  of  lead  and  by 
hydrated  oxide  of  lead  ;  nitrate  of  silver  is  reduced  on  boiling 
in  the  presence  of  ammonia ;  neutral  sesquichloride  of  iron  pro- 
duces a  bluish  color,  changing  to  yellow  on  boiling  and  sepa- 
rating, on  cooling  a  deep  yellow  precipitate.  No  alteration 
occurs  with  protosalts  of  iron,  and  a  slow  reduction  with  alka- 
line oxide  of  copper  ;  acetic  acid  dissolves  daphnine  unaltered; 
nitric  acid  colors  it  red,  dissolves  it  and  produces,  on  heating, 
oxalic  acid.     Its  composition  is  Cg2       Ogg+S  HO. 
Daphnine  is  decomposed  into  sugar  and  daphnetine  by  sul- 
phuric and  muriatic  acid,  by  emulsin,  by  yeast  in  the  presence 
of  a  little  glucose,  and  by  dry  distillation.  This  product  is  a 
weak  acid,  slightly  astringent,  very  soluble  in  boiling  water  and 
alcohol,  little  in  ether,  and  crystallizes  in  colorless  prisms.  It 
is  colored  red  by  nitric  acid,  precipitated  yellow  by  lime-  and 
baryta  water  and  by  acetate  and  subacetate  of  lead ;  it  reduces 
nitrate  of  silver  and  alkaline  solutions  of  copper,  and  produces, 
with  neutral  persalts  of  iron,  an  intensely  green  color,  disap- 
pearing by  excess  of  the  ferric  salt  and  by  free  acid ;  ferrous 
