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ON  THE  BERRIES  AND  BARK  OF  RHUS  GLABRUM. 
Botanical  Description. 
The  Rhus  glabrum  is  an  indigenous  shrub,  belonging  to  the 
natural  order  Anacardiacese,  and  in  the  sexual  system  to  Pentandria 
Trigynia.  This  plant  is  from  four  to  twelve  feet  high,  with  a 
stem  usually  more  or  less  bent,  and  divided  into  straggling  branches, 
covered  with  a  smooth  light-gray  or  somewhat  reddish  bark.  The 
leaves  are  upon  smooth  petioles,  and  consist  of  many  pairs  of  op- 
posite leaflets,  with  an  odd  one  at  the  extremity,  all  of  which  are 
lanceolate,  acuminate,  acutely  serrate,  glabrous,  green  on  their 
upper  surface,  and  whitish  beneath.  In  the  autumn  their  color 
changes  to  a  beautiful  red. 
The  flowers  are  greenish-red,  and  disposed  in  large,  erect, 
terminal,  compound  thyrses,  which  are  succeeded  by  clusters  of 
small  crimson  berries  covered  with  a  silky  down. 
This  shrub  is  found  in  almost  all  parts  of  the  United  States, 
growing  in  old  neglected  fields,  along  fences,  and  on  the  borders 
of  woods,  seeming  to  prefer  hill  sides,  and  the  steep  banks  along 
rivers,  where  it  grows  very  luxuriantly,  and  when  the  berries  are 
ripe  presents  a  beautiful  appearance  when  seen  at  a  distance. 
Analysis  of  the  Bark  of  the  Boot. 
The  bark  of  the  root  is  of  a  light  gray  color,  with  a  tinge  of  red 
externally,  yellowish  white  internally,  having  a  very  astringent 
and  slightly  sweet  taste. 
The  specimen  examined  was  collected  in  the  latter  part  of 
April. 
A  cold  infusion  was  made  from  the  bark,  by  maceration  and 
displacement,  which  was  of  a  light  brown  color,  tinged  with  red, 
and  had  the  taste  and  odor  of  the  bark.  It  gave  an  acid  reaction 
with  litmus  paper. 
Albumen. — The  presence  of  albumen  was  evinced  in  the  cold 
infusion,  by  solutions  of  tannin  and  corrosive  sublimate,  and  also 
by  coagulating  with  heat. 
Tannic  Acid. — The  muriatic  tincture  of  iron,  when  added  to  the 
cold  infusion,  produced  a  bluish»black  precipitate;  precipitates 
were  also  produced,  with  solutions  of  gelatine  and  quiniae. 
Gum. — A  cold  infusion  was  made,  and  deprived  of  its  tannin  by 
adding  gelatine  in  excess,  filtered,  and  boiled  to  remove  the  albu- 
men, again  filtered,  and  subacetate  of  lead  added,  which  produced 
a  precipitate. 
