526 
CATHARTIN  FROM  RHAMNUS  CATHARTICA. 
For  the  detection  of  a  smaller  proportion  of  picric  acid  in  beer 
than  that  above  mentioned,  it  is  necessary  to  concentrate  the 
liquid  before  adding  the  reagents  Lond.  Pharm.  Journ.,  Sept., 
1853,  from  Journal  de  Chimie  Medicate. 
ON  CATHARTIN  OBTAINED  FROM  THE  BERRIES  OF  RHAMNUS 
CATHARTICA. 
By.  F.  L.  Winkle  r. 
To  obtain  the  purgative  principle  of  these  berries,  fifteen 
pounds  of  them,  when  quite  green,  (collected  in  September,) 
were  bruised  and  expressed.  The  juice  had  a  dark  violet  color, 
an  extremely  bitter  taste,  and  evaporated  by  means  of  a  water 
bath,  remained  as  a  dark  brown  syrup.  This  was  then  exhausted 
several  times  by  boiling  hot  alcohol  (absolute)  until  the  latter  had 
but  a  slightly  bitter  taste.  The  united  tinctures  became  turbid 
after  cooling ;  they  were  then  filtered  and  mixed  with  four  times 
as  much  sulphuric  ether,  A  large  quantity  of  slightly  bitter, 
dark-colored,  extractive  matter  separated,  containing  no  sugar. 
The  filtered  solution  of  cathartin  in  ether  and  alcohol  was  dis- 
tilled in  a  water-bath,  the  cathartin  remaining  with  the  coloring 
matter,  then  treated  again  in  the  same  way,  and  2|  ounces  of 
pure  cathartin  were  obtained. 
The  residuum  of  the  expressed  berries  was  boiled  with  six  or  eight 
times  its  weight  of  water,  set  aside  for  several  days,  and  a  good 
quantity  of  impure  Rhamnin  obtained.  This  was  then  collect- 
ed on  a  filter  of  dense  linen,  washed  with  water,  dried,  and  ap- 
peared as  a  greenish  gray  mass,  of  a  slightly  bitter  taste,  loosely 
coherent.  This,  again  dissolved  in  alcohol,  was  decolorized  by  ani- 
mal charcoal,  separated  by  the  addition  of  water,  and  thus  ob- 
tained in  a  pure  state.  The  dry  mass  was  dissolved  again  in  ab- 
solute alcohol,  and  by  slow  evaporation  ten  drachms  of  pure 
Rhamnin,  crystallized  in  pale  yellow  crystals,  similar  to  cauli- 
flowers, of  a  peculiar  taste,  little  distinct,  almost  like  dough  ;  it  is 
not  soluble  in  cold  alcohol  nor  ether,  but  readily  soluble  in 
boiling  alcohol,  and  forms  a  mucilage,  if  boiled  in  water. 
It  is  dissolved  by  caustic  alkalies  and  their  carbonates,  with 
saffron  yellow  color,  tasting  almost  like  grape  sugar,  and  deco- 
