558  Resin  of  Ginger.  {Ami°v.r;iSarm' 
Schlatter1  discovered  in  Peucedanum  officinale  a  neutral  crystalline 
principle — peucedanin.  As  the  present  analysis  was  for  the  determi- 
nation of  the  constituents  which  have  a  food  value,  and  the  supply  of 
material  by  this  work  was  nearly  exhausted,  I  was  unable  to  do  more 
than  apply  Heut's2  method  for  the  preparation  of  peucedanin,  to 
about  25  gms.  of  the  original  substance.  By  this  means,  however,  a 
small  quantity  of  a  distinct  crystalline  substance  was  obtained,  nearly 
pure,  which,  so  far  as  could  be  determined,  was  identical  with  the  above 
compound. 
RESIN  OF  GINGER, 
By  Eobert  Glenk. 
In  preparing  the  "  Liquor  Zingiberis,"  or  soluble  essence  of  ginger 
of  the  National  Formulary,  the  resin  is  separated  by  the  addition  of 
water  to  the  fluid  extract  by  the  intervention  of  pumice  in  powder, 
which  acts  as  a  nucleus  to  attract  the  precipitated  resin  and  allow  of 
more  rapid  filtration. 
On  drying  the  pumice  which  remains  on  the  filter  and  exhausting 
it  with  warm  alcohol  a  solution  of  the  resin  is  obtained.  On  the 
evaporation  of  the  alcohol  a  semi-solid  residue  is  left  of  a  black  color 
and  an  odor  slightly  differing  from  that  of  the  root.  Its  alcoholic 
solution  is  of  an  acid  reaction.  About  two-thirds  of  the  resin  is 
soluble  in  solution  of  potassa,  and  the  dissolved  portion  is  reprecipi- 
tated  on  adding  an  excess  of  HC1.  The  portion  insoluble  in  5  per 
cent.  KOH  dissolves  in  glycerin  on  slightly  warming  and  is  reprecipi- 
tated  on  diluting  with  warm  water.  It  is  almost  insoluble  in  water 
of  ammonia. 
Castor  oil,  ether,  acetic  ether,  chloroform  and  acetone  completely  dis- 
solve the  resin ;  carbon  disulphide,  turpentine  and  petroleum  benzin 
dissolve  only  partially.  On  adding  a  few  drops  of  tincture  of  chlor- 
ide of  iron  to  a  dilute  alcoholic  solution,  a  gradual  darkening  in  color 
results.  In  a  solution  in  five  per  cent.  KOH  (1-10)  on  the  addition 
of  test  solution  of  permanganate  of  potassium,  a  dark  green  color  is 
produced  which  fades  in  half  a  minute.  With  HC1  (1*160)  no  effect 
is  produced.  H2S04,  sp.  g.  1-84,  dissolves  the  resin  with  a  black 
color ;  the  solution  is  precipitated  by  the  addition  of  water,  and  after 
washing  with  water  the  mass  is  almost  insoluble  in  alcohol.  HN03 
1  Ann.  Chem.  und  Pharm.,  v,  p.  201. 
2  Dissertation,  Erlangen,  1874. 
