AD4cembef,hi9oa'}    Recent  Literature  Relating  to  Pharmacy.  593 
normal  iodine,  and  from  the  difference  in  the  titration  figures  of  the 
two  solutions  the  amount  of  berberine  is  reckoned  by  the  following 
factors  : 
One  cubic  centimetre  T^  n.  iodine  =0  00262  gramme  potassium 
^-naphtalin  thiosulphonate. 
One  gramme  potassium  ' /9-naphtalin  thiosulphonate  —  16927 
grammes  berberine  hydrochlorate. — (Troeger  and  Linde,  Arch.  Ph., 
1900,4.)  H.V.  A. 
THE  DYESTUFF  OF  ANNATTO. 
This  product  yields  bixin,  which  is  best  extracted  by  treatment 
with  chloroform  (using  an  invert  condenser),  the  dried  extract 
freed  from  fat  by  extraction  in  Soxhlet  apparatus  with  ligroin,  and 
the  residue  extracted  in  same  apparatus  with  chloroform. 
The  crystals,  obtained  by  evaporation  and  always  finally  dried, 
first  on  air-bath,  then  on  .vater-bath,  are  further  purified  by  successive 
treatment  with  ligroin  and  chloroform. 
The  pure  crystals  are  violet-red,  melt  at  187-5°  C,  and  have 
composition  C28H3405.  Zeissel's  method,  confirmed  by  Beckman's, 
shows  that  bixin  contains  one  methoxyl  group  (OCH3),  but  none  of 
the  hydroxyl  group  tests  are  answered. 
Both  reduction  and  oxidation  break  it  into  substances  of  no  value 
in  establishing  its  structural  formula ;  the  same  being  true  of  fusion 
tests  (with  potassa,  etc.),  and  of  treatment  with  concentrated  nitric 
acid.  Curiously  enough,  superheated  steam  splits  palmitic  acid 
from  it. 
It  yields  a  phenyl  hydrazine  compound  and  a  di-potassium*  salt, 
results  so  conflicting  with  analytical  formula  that  its  structure  can- 
not be  safely  established  as  yet.  Annatto  contains  no  yellow  dye- 
stuff,  hence  the  so-called  orellin  of  the  earlier  investigators  is  purely 
imaginary. — (K.  G.  Zweck,  Arch.  Ph.,  1900,  58.)  H.  V.  A. 
'     THE  EMODINS  OF  ALOES  AND  FRANGULA. 
These  two  bodies  are  isomeres,  both  being  C15H10O5,  that  is, 
trioxymethylanthraquinone. 
Aloe  emodin  melts  at  223°  C,  dissolves  in  concentrated  sulphuric 
acid  with  a  red  color,  which  gives  a  green-yellow  color  to  water  by 
pouring  therein.  A  drop  of  the  sulphuric  acid  solution  added  to 
water  supersaturated  with  ammonia  gives  a  reddish-violet  color. 
Baryta  water  yields  a  rose-colored  liquid  with  aloe- emodin.  The 
