ON  GRATIOLA  OFFICINALIS. 
341 
cold  water,  which  dissolves  the  greater  part,  gratiosolin  ;  the 
insoluble  residue  is  gratiolin,  which  is  entirely  freed  from  gra- 
tiosolin by  precipitating  its  concentrated  alcoholic  solution  by 
water,  and  from  gratiolacrin  by  precipitating  this  from  the  alco- 
holic solution  with  sugar  of  lead  ;  it  is  recrystallized  from  boiling 
water.    Its  composition  is  C40  H34  014. 
By  continued  boiling  with  dilute  sulphuric  acid,  it  is  decom- 
posed into  sugar  and  an  oily  liquid,  solidifying  on  cooling  to  a 
yellow  resinous  mass,  soluble  in  alcohol  and  ether,  gratioleretin, 
and  into  brilliant  white  prisms,  insoluble  in  water  and  ether, 
soluble  in  alcohol,  coloring  oil  of  vitriol  green,  gratioletin. 
2  ^40  ^34  ^14  =    ®12  H12  Ol2  +  ^34  ^28  ^6    +  ^34  H28  ^10* 
Gratiolin.  Glucose.  Gratioleretin.  Gratioletin. 
Gfratiosolin  constitutes  the  principal  part  of  the  crude  gratiolin, 
from  which  it  is  gained  by  washing  with  water,  evaporating  the 
solution  and  washing  the  product  with  anhydrous  ether  ;  its 
composition  is  C46  H42  025.  At  ordinary  temperature  it  is  de- 
composed by  alkalies  and  dilute  acids  into  grape  sugar  and  gra- 
tiosoletin  C40  H34  017,  which  is  likewise  soluble  in  water  and  pre- 
cipitated by  tannin.  When  pure  it  is  of  a  golden  yellow  color, 
very  bitter  taste,  easily  soluble  in  water  and  alcohol,  insoluble  in 
ether.  Its  aqueous  solution  when  heated  with  diluted  acid,  is 
decomposed  into  sugar  and  a  resinous  substance,  the  latter  being 
a  mixture  of  two  bodies  separable  by  ether.  Grratiosoleretin  C34 
H26  09  has  a  yellow  color,  scarcely  any  taste  or  smell,  is  inso- 
luble in  water,  easily  soluble  in  alcohol  and  ether.  Hydrogra- 
tiosoleretin  C34  H28  On  has  a  purely  yellow  color,  and  faint  re- 
sinous odor;  it  is  insoluble  in  water  and  absolute  ether,  but 
soluble  in  alcohol. 
O-ratiolacrin.  The  crude  gratiolacrin,  as  obtained  on  treating 
crude  gratiolin  with  ether,  is  a  very  bitter  acrid  resin,  containing 
a  fixed  oil  from  which  it  may  be  freed  by  solution  in  cold  abso- 
lute alcohol.  The  residue  is  partly  dissolved  by  ammonia  of 
•960  spec.  grav. ;  the  insoluble  part,  when  treated  with  cold 
alcohol,  leaves  a  white  crystalline  powder,  crystallizing  in  fine 
white  crystals  from  boiling  alcohol. 
The  cold  alcohol  solution  has  an  intensely  acrid  burning  and 
bitter  taste ;  by  precipitating  with  sugar  of  lead  and  decompos- 
