216 
GREEN  FRUIT  OP  DIOSPYROS  VIRGINIANA. 
excess  of  the  precipitant ;  and  on  adding  to  the  infusion  a  few 
drops  of  tincture  of  chloride  of  iron  it  gave  a  deep  olive  green 
color. 
2d.  An  infusion  was  made  the  same  as  before,  and  refusing  to 
filter,  I  heated  it  to  the  boiling  point,  expecting  to  find  it  pre- 
cipitate ;  no  such  effect  taking  place,  I  continued  the  evaporation 
to  dryness.  Then,  on  powdering  this  extract,  and  treating  it 
with  washed  ether,  the  ethereal  liquid  gave  me  by  evaporation 
one-twentieth  of  the  weight  of  the  extract  used,  of  nearly  pure 
tannin,  of  a  light  green  color,  still  striking  the  olive  green  color 
with  a  persalt  of  iron. 
A  portion  of  the  residue  was  incinerated  in  a  test  tube  and 
gave  an  ash  entirely  neutral  to  test  paper. 
3d.  A  portion  of  the  fruit  was  gathered  in  the  latter  end  of 
October.  They  were  now  of  their  full  size,  and  beginning  to 
turn  from  green  to  a  yellow  color,  very  juicy  and  sweet  and 
astringent. 
An  infusion  still  gave  precipitates  with  the  former  tests,  and 
the  same  olive  color  with  tincture  of  muriate  of  iron.  It  was 
much  thicker  and  more  mucilaginous  than  the  former.  It  was 
evaporated  to  the  consistence  of  an  extract,  which,  I  observed, 
absorbed  moisture  in  damp  situations  and  became  soft  and  plia- 
ble like  India  rubber.  A  portion  of  these  berries  were  sliced 
transversely  and  carefully  dried.  The  segments  were  hard  and 
brittle  in  dry  weather,  but  in  a  damp  atmosphere  became  quite 
soft  and  pliable.  They  lost  by  the  process  112j  parts  in  150, 
but  still  retained  their  astringency. 
From  the  fact  that  the  infusions  refused  to  precipitate  when 
boiled,  the  extracts  being  gummy  and  soft,  and  the  dried  fruit 
absorbing  moisture,  I  inferred  there  was  pectin  present.  Ac- 
cordingly an  infusion  of  the  dried  fruit  was  boiled  with  carbon- 
ate of  potassa,  and  then  muriatic  acid  added  gave  a  gelatinous 
precipitate  characteristic  of  pectic  acid. 
4th.  480  grains  of  the  dried  fruit  were  digested  in  alcohol, 
decanted  and  evaporated,  which  left  a  saccharine  mass,  having 
an  astringent  taste.  This  mass  amounted  to  180  grains,  par- 
tially soluble  in  water,  seemingly  decomposed  by  a  solution  of 
caustic  potassa,  giving  a  deep  brown  color.  It  was  soluble  in 
strong  sulphuric  acid,  giving  the  same  dark  color. 
