ON  A  FALSE  CINCHONA  BARK  OF  INDIA. 
353 
cuprous  oxide  was  immediately  produced.  An  aqueous  solution 
of  the  crystals  only  precipitated  the  cupric  solution  on  prolonged 
boiling.  The  substance  therefrom  appeared  to  be  a  conjugate 
compound  of  grape  sugar. 
The  purified  crystals  were  dried  in  vacuo  over  sulphuric  acid 
for  several  days.  They  were  then  submitted  to  analysis,  and 
then  yielded  the  following  numbers : — 
I.  0-4793  grm.  burnt  with  cupric  oxide  yielded  0*9147  grm. 
carbonic  acid  and  0*2209  grm.  of  water. 
II.  0*4176  grm.  yielded  0*7937  grm.  carbonic  acid  and  0*1995 
grm.  water. 
I  found  on  comparison  that  the  foregoing  numbers  closely 
correspond  with  those  yielded  by  aesculin,  the  fluorescent  and 
crystalline  principle  of  horse-chestnut  bark  discovered  by 
Fleischmann,  and  subsequently  analysed  by  TromsdorfF  in 
1835.*    This  is  clearly  shown  by  the  following  comparison  : — 
JEsculin. 
I. 
II. 
c21  .  . 
252  . 
.    52*06  . 
.    52*04  . 
.  51-90 
K24  •  • 
24  . 
.     4*96  . 
.     5*12  . 
.  5*31 
o13 
208  . 
.    42*98  . 
.    42-84  . 
.  42-79 
414 
100*00 
100*00 
100*00 
Rochleder  and  Schwarsf  found  that  on  boiling  sesculin  with 
hydrochloric  acid  it  split  up  into  sesculetin  and  grape  sugar. 
C21H2A3+3H20=C9HA+2CGH1206. 
When  the  crystalline  substance  obtained  as  above  is  boiled 
with  hydrochloric  acid  for  a  few  minutes,  and  allowed  to  cool, 
needle-like  crystals,  having  all  the  appearance  of  aesculetin, 
separate.  When  these  latter  are  boiled  with  a  solution  of  ferric 
chloride  a  fine  green  coloration  and  precipitate  are  produced  ; 
this  reaction  is  characteristic  of  sesculetin.  I  consider  it  there- 
fore proved  that  the  crystalline  substance  obtained  from  Hyme- 
nodictyon  excelsum  is  identical  with  aesculetin. 
It  is  a  somewhat  singular  circumstance  that  the  bitter  princi- 
ple of  this  Indian  tree  should  be  the  same  as  that  of  the  horse- 
*  Annalen  d.  Chemie  und  Pharmacie,  Bd.  xiv.  198. 
f  Ibid,  lxxxvii.  186. 
23 
