Am.  Jour.  Pilar m.  \ 
March,  1887.  J 
Hyd i  -a  i igea  Arboi 'escen s. 
123 
In  order  to  obtain  a  larger  quantity  500  grams  of  the  drug  were 
prepared  and  percolated  to  exhaustion  with  95  per  cent,  alcohol.  The 
greater  portion  of  the  alcohol  being  recovered  by  distillation,  the 
concentrated  extract  was  allowed  to  evaporate  spontaneously,  which 
left  a  viscid  brownish  red  mass.  After  shaking  with  petroleum 
spirit  to  remove  a  fixed  and  volatile  oil,  the  residue  was  treated 
with  a  slightly  acidulated  water  and  chloroform  to  remove  the  red 
coloring  matter.  The  acidulated  solution  was  shaken  with  ether 
several  times,  the  ethereal  washings  on  evaporation  deposited  the 
bodv  in  stellate  clusters  in  fair  state  of  purity. 
CRYSTALS  OF  HYDRANGIN  (Natural  Size). 
After  confirming  its  glucosidal  character,  the  name  hydrangin  is 
proposed  for  it.  On  addition  of  an  alkali  to  the  aqueous  solution  a 
very  distinct  and  strong  opal  blua  fluorescence  is  observed,  which  is 
destroyed  in  acidifying.  This  characteristic  fluorescent  property  was 
noticed  in  all  the  solvents  used  in  exhausting  the  drug  except  the 
petroleum  spirit  and  dilute  hydrochloric  acid. 
From  its  fluorescent  property  it  was  thought  to  be  similar  to  or 
identical  with  aesculin,  a  glucoside  prepared  from  horse  chestnut,  but 
on  comparison  they  were  found  to  be  distinct  bodies.  The  fluor- 
escence of  hydrangin  is  opal  blue,  while  that  of  sesculin  is  sky  blue. 
Hydrangin  also  differs  from  sesculin  by  its  ready  solubility  in  ether, 
its  insolubility  in  strong  hydrochloric  acid  and  by  its  not  being  pre- 
cipitated by  argentic  nitrate,  mercuric  chloride,  nor  neutral  lead 
acetate.  Hydrangin  is  not  charred  by  concentrated  sulphuric  acid, 
but  dissolves  without  color ;  also  with  nitric  acid.  A  characteristic 
reaction  for  hydrangin  is  obtained  on  dissolving  it  in  sulphuric  acid 
and  adding  a  small  crystal  of  potassium  bichromate  when  a  dark 
purple  color  is  produced  which,  after  some  minutes,  fades  to  violet ; 
and  on  addition  of  a  few  drops  of  water  an  olive  green  is  produced 
which  gradually  fades. 
Hydrangin  melts  at  235°  C.  and  on  increasing  the  temperature 
slightly,  sublimes  without  decomposition,  forming  in  stellate  clusters, 
