ON  A  SPURIOUS  EXTRACT  OF  JALAP. 
117 
That  part  of  the  alcoholic  extract  not  soluble  in  ether,  is  a 
soft  resin,  soluble  in  caustic  potash,  and  is  precipitated  by  acids 
in  excess. 
Acetic  Acid  dissolved  the  resin,  forming  a  muddy  yellow  so. 
lution. 
Sulphuric  Acid,  concentrated,  chars  and  dissolves  the  resin. 
Hitric  Acid,  35°  B.,  when  cold,  forms  with  the  resin  a  turbid 
yellow  solution. 
The  ethereal  resin  has  a  red  color,  yellow  on  the  edges. 
Caustic  Alkalies  dissolve  the  resin  freely,  forming  a  red  solu- 
tion. 
Nitric  Acid,  35°  B.  when  hot,  decolorizes  the  resin,  rendering 
it  crisp  and  friable. 
Chloroform  dissolves  the  resin  freely,  forming  a  light  yellow 
solution. 
Pure  Benzole  dissolves  the  resin  freely,  forming  a  light  yellow 
solution. 
When  chloride  of  sodium  is  added  to  the  alkaline  solution  of 
the  resin  and  heated,  the  resin  separates  entirely. 
The  extract  contains  8  per  cent,  of  inorganic  matter,  which 
effervesces  on  addition  of  acid. 
The  hard  or  active  resin  of  Jalap  is  distinguished  from  the 
other  resins  we  have  considered,  by  not  being  precipitated  from 
its  combination  with  the  caustic  alkalies,  when  acid  in  excess  is 
added. 
Podophyllin  differs  from  the  other  resins,  by  its  solubility  in 
the  carbonated  alkalies,  and  by  dissolving  in  cold  nitric  acid  of 
35p  B.  forming  a  deep  red  solution. 
Resin  of  Scammony  is  insoluble  in  benzole,  but  soluble  in 
chloroform,  thus  differing  from  jalap  and  podophyllin  which 
are  insoluble  in  chloroform. 
Resin  of  Gamboge  differs  from  all  the  other  resins  by  its 
ready  solubility  in  pure  benzole,  and  separating  from  its  alkaline 
combination  on  addition  of  chloride  of  sodium. 
From  these  experiments  we  deduce  the  conclusion  that  the  ex- 
tract under  examination  owes  its  medicinal  qualities  to  34  per 
cent,  of  resin  of  gamboge,  equivalent  to  42  per  cent,  of  gam- 
boge contained  in  it,  and  contains  no  resin  of  jalap  or  podo- 
phyllin. 
Philadelphia,  January,  1862. 
