196 
ON  THE  BERRIES  AND  BARK  OF  RHUS  GLABRUM. 
The  specimen  of  sumach  galls  which  I  examined,  was  an  in- 
ferior one,  from  being  collected  late  in  the  season,  and  yielded 
only  six  per  cent,  of  tannic  acid,  about  three  per  cent,  of  gallic 
acid,  together  with  albuminous  and  coloring  matter. 
Analysis  of  the  Berries, 
The  appearance  of  sumach  berries  is  familiar  to  every  drug- 
gist, they  grow  in  large  clusters,  and  are  generally  of  a  crimson 
color,  and  covered  with  a  silky  down. 
Two  specimens  of  berries  were  examined,  one  of  which  was  col- 
lected in  the  latter  part  of  August,  and  the  other  late  in  Septem- 
ber. The  specimen  collected  in  August  was  of  a  deep  red  color, 
and  slightly  acid  taste,  and  the  berries  were  completely  covered 
with  the  silky  down  peculiar  to  them.  When  examined  under 
the  microscope,  the  silky  down  appeared  to  be  a  mass  of  tubular 
hairs  of  a  white  color,  enveloped  in  a  crystalline  coating  of  bima- 
late  of  lime,  impregnated  with  red  coloring  matter,  resembling 
an  icicle  in  appearance. 
The  specimen  collected  in  September  was  of  a  crimson  red 
color,  and  very  acid  taste,  and  when  examined  under  the  micro- 
scope the  berries  were  found  to  be  nearly  devoid  of  the  peculiar 
silky  down,  but  were  covered  with  a  deep  red  coating  of  moist 
matter,  as  if  due  to  the  presence  of  a  deliquescent  salt. 
Tannic  Acid  The  presence  of  tannic  acid  in  sumach  berries 
was  determined  by  the  following  test:  the  tincture  of  muriate  of 
iron,  produced  a  bluish  black  precipitate,  when  added  to  the  cold 
infusion.  Precipitates  were  also  produced  with  solutions  of  gela- 
tine and  tartar  emetic. 
Grallic  Acid. — An  infusion  was  made  with  boiling  water,  the 
tannic  acid  removed  by  adding  gelatine  in  excess,  filtered,  and 
the  filtered  liquor  evaporated  to  an  extract,  which  was  treated 
with  ether,  and  the  ethereal  solution  allowed  to  evaporate  spon- 
taneously, when  it  yielded  a  substance  of  a  light  yellow  color 
and  slightly  crystalline  form,  which,  when  dissolved  in  water,  and 
solution  of  sesquisulphate  of  iron  added,  produced  a  greenish 
black  coloration  entirely  dissipated  by  heat. 
Fixed  Oil — One  hundred  grains  of  the  berries,  collected  late 
in  August,  were  bruised,  and  treated  with  cold  ether  by  displace- 
ment, and  the  ethereal  tincture  allowed  to  evaporate  spontane- 
