254  On  the  Bark  q/Juglans  Cinerea.  {A%iTiJs^ 
bath,  exhausted  by  alcohol,  and  the  alcoholic  solution  evaporated  in 
the  drying  closet  to  a  resin-like  extract.  This  was  redissolved  in 
alcohol,  and  set  aside  in  a  cool  place.  After  a  few  days  small  acicu- 
lar  crystals  were  found  floating  on  the  liquid.  These  crystals  were 
in  small  quantity,  colorless,  and  colored  litmus  red. 
The  filtrate  was  freed  from  lead  by  hydrosulphuric  acid,  and  evap- 
orated to  dryness  on  a  water-bath ;  the  residue,  exhausted  by  alcohol 
and  evaporated,  yielded  a  bitter  extract  like  mass,  soluble  in  both 
alcohol  and  water. 
These  results  not  proving  satisfactory  by  the  isolation  of  an  acid 
in  quantity  sufficient  for  further  examination,  the  peculiar  solvent 
properties  of  true  benzole  were  brought  into  requisition. 
A  portion  of  the  freshly  dried  and  powdered  bark  was  macerated 
in  this  menstruum  for  four  days.    The  benzole,  which  at  first  was 
colorless,  after  separation  from  the  refuse  matters  by  expression  and 
filtrationT  was  of  a  decided  bright  yellow  color.    This  was  set  aside 
and  allowed  to  evaporate  spontaneously.    After  the  evaporation  had 
been  carried  on  until  the  residue  ceased  to  lose  weight,  the  capsule- 
was  found  to  contain  a  thick  oily  substance,  and  the  sides  were  cov- 
ered by  short  acicular  crystals  of  a  bright  orange-yellow  color.  These 
exhibit  decided  acid  properties  to  litmus,  are  soluble  in  alcohol  and 
ether,   but  scarcely  so  in  water.     They  volatilize  without  fusing^ 
in  solution  are  reddened  by  ammonia,  and  are  turned  pale  violet  by 
potassa,  afterwards  becoming  red.    The  oily  residue  remaining  after 
the  evaporation  of  the  benzole,  was  exhausted  with  alcohol,  and  the 
alcoholic  solution  by  spontaneous  evaporation  yielded  crystals  similar 
in  form,  size  and  reaction  to  those  deposited  on  the  side  of  the  cap- 
sule. The  residue  insoluble  in  alcohol  was  taken  up  by  ether,  allowed 
to  evaporate  spontaneously  to  a  syrupy  consistence,  and  spread  on 
bibulous  paper;  thin  tabular  crystals  were  obtained  which  were  colorless^ 
acid  to  litmus,  insoluble  in  water,  scarcely  so  in  alcohol,  but  readily 
taken  up  by  ether,  which  solution  was  not  precipitated  by  chloride  of 
calcium  and  not  affected  in  color  by  ammonia  or  potassa.    They  are 
fusible,  but  being  farther  heated  partly  volatilize,  leaving  behind  a 
charred  mass,  which  burns  without  residue.    The  crystals  when  fused 
are  changed  to  a  dark  red  liquid,  which  when  treated  by  ether  be- 
comes decolorized. 
Chrysophanic  acid  is  soluble  in  benzole,  and  since  from  juglans,  by 
the  use  of  the  same  solvent,  a  product  is  obtained  which  exhibits  some* 
