ON  THE  BERRIES  AND  BARK   OF  RHUS  GLABRUM. 
197 
ously,  yielding  a  residue  weighing  thirty  grains,  which  was  shaken 
up  with  water  to  remove  the  tannic  and  gallic  acids,  and  allowed 
to  stand  for  a  short  time,  when  an  oily  matter  was  found  floating 
on  the  water.  This,  when  separated,  weighed  fifteen  grains.  It 
was  found  to  be  a  fixed  oil,  by  giving  a  greasy  stain  to  paper, 
which  did  not  disappear  by  heating  ;  it  also  burnt  with  a  smoky 
flame,  and  was  saponified  by  potash.  It  was  miscible  in  all  pro- 
portions with  chloroform,  and  but  slightly  soluble  in  alcohol.  It 
is  probable  that  the  oil  exists  in  the  kernels  of  the  seed,  as  it  can- 
not be  obtained  but  in  very  small  quantity  from  the  unbruised 
berries. 
Malic  Acid  and  Bimalate  of  Lime. — The  quantity  of  free 
malic  acid  in  the  berries  was  estimated  by  making  a  tincture 
with  cold  alcohol  (bimalate  of  lime  being  insoluble  in  cold  alco- 
hol) and  evaporating  carefully  to  dryness,  dissolving  the  alco- 
holic extract  in  water  and  adding  acetate  of  lead  to  this,  so  as  to 
obtain  the  malic  acid  as  malate  of  lead.  The  malate  of  lead  was 
afterwards  decomposed  by  means  of  sulphuretted  hydrogen,  by 
which  the  malic  acid  was  liberated,  and  it  was  isolated  by  filter- 
ing and  evaporating  the  solution  carefully  to  dryness.  The  quan- 
tity of  bimalate  of  lime  present  was  estimated,  by  burning  the 
aqueous  extract  obtained  from  a  given  amount  of  the  berries, 
treating  the  ashes  with  an  excess  of  nitric  acid,  filtering,  and  pre- 
cipitating the  filtered  liquor,  with  oxalate  of  ammonia  in  excess, 
so  as  to  obtain  the  lime  present  as  oxalate. 
Bimalate  of  lime  readily  crystallizes  from  a  concentrated  aque- 
ous solution  of  the  berries,  the  size  of  the  crystals  depending 
upon  the  mode  of  evaporation,  being  much  larger  if  evaporated 
spontaneously. 
Two  specimens  of  berries  collected  at  different  times  were  an- 
alyzed. The  first  collected  in  the  latter  part  of  August,  yielded 
7.46  per  cent  of  bimalate  of  lime,  and  0.50  per  cent  of  free  malic 
acid.  The  second  specimen,  collected  late  in  September,  yielded 
3.50  per  cent,  of  bimalate  of  lime,  and  2.75  per  cent,  of  uncom- 
bined  malic  acid. 
Which  proves  that  berries  collected  at  different  times  in  the 
season,  vary  much  in  the  quantity  of  malic  acid  and  bimalate  of 
lime  which  they  contain. 
Red  Coloring  Matter. — A  portion  of  the  berries  were  treated 
