200  Alcoholic  Extract  of  the  Root  of  Atropa  Belladonna.  { Am^f  $g*m- 
To  determine  to  what  extent  the  reaction  can  be  used  as  a  test  for 
atropine,  and  the  best  conditions  for  applying  it,  I  made  some  experi- 
ments, of  which  the  following  gave  the  best  result : — Dissolve  0*208 
gm.  of  fresh  precipitated  mercurous  oxide  very  carefully  in  dilute 
nitric  acid,  avoiding  excess ;  it  is  better  to  leave  a  trace  of  oxide  un- 
dissolved; now  dilute  the  product  to  78  c.c.  with  water,  which  gives 
a  solution  containing  nearly  one-third  per  cent,  mercurous  nitrate. 
Prepare  a  1  per  cent,  solution  of  atropine,  by  dissolving  the  pure 
alkaloid  in  a  mixture  of  20  volumes  alcohol  and  80  volumes  water. 
On  mixing  drops  of  each  of  the  solutions  on  a  watch  glass,  resting  on 
a  sheet  of  white  paper,  a  black  precipitate  is  at  once  produced,  conse- 
quently indicating  less  than  O001  gm.  of  atropine.  If  the  test  be 
done  in  a  test  tube  with  1  c.c.  of  each  solution,  the  blackening  is  ren- 
dered more  apparent,  owing  to  the  greater  volume  of  precipitate.  That 
the  alcohol  has  no  influence  on  the  reduction  was  proved  by  a  negativ- 
experiment,  also  by  the  fact  that  a  hot  simple  aqueous  solution  of 
atropine,  made  by  boiling,  reacts  powerfully  with  mercurous  nitrate. 
Experiments  made  with  mercurous  acetate  did  not  give  such  good 
results  as  the  nitrate. — Phar.  Jour,  and  Trans.,  March  6, 1886,  p.  762. 
THE  ALCOHOLIC  EXTRACT  OF  THE  ROOT  OF  ATROPA 
BELLADONNA.1 
By  Professor  Wyndham  Dunstan  and  Francis  Ransom. 
Since  the  completion  of  the  last  part  of  this  inquiry2  an  alcoholic  ex- 
tract of  the  root  of  Atropa  Belladonna  has  been  made  official  in  .the  new 
British  Pharmacopoeia.  In  the  present  paper  the  results  of  chemical 
experiments  are  described,  which  were  instituted  for  the  purpose  of 
(i.)  devising  a  satisfactory  method  of  estimating  the  total  alkaloid,  and 
(ii.)  determining  whether  the  extract  as  met  with  in  commerce  varies 
1  Read  at  an  Evening  Meeting  of  the  Pharmaceutical  Society,  Wednesday, 
March  10, 1886. 
2  The  papers  already  published  are  "  The  Assay  of  Atropa  Belladonna.  Part 
I.  The  Estimation  of  the  Alkaloids  in  the  Root  of  Atropa  Belladonna."  Part 
II.  "  The  Estimation  of  the  Alkaloids  in  the  Leaves  of  Atropa  Belladonna." 
"  Chemical  Report  on  the  Pharmaceutical  Preparations  of  Atropa  Belladonna. 
Part  I.  The  Alcoholic  Extract  of  the  Leaves  of  Atropa  Belladonna." — See 
Amer.  Jour.  Pharm.,  1884,  p.  279,  and  1885,  pp.  532  and  534. 
