156         ON  AN  EASY  METHOD  OP  PREPARING  ATROPINE. 
importance  to  the  general  physician,  is  generally,  I  believe,  pro- 
cured from  the  root  of  the  Atropa  belladonna  by  digestion  in 
alcohol,  so  as  to  form  a  tincture,  to  which  lime  is  added  to  preci- 
pitate the  atropine,  then  sulphuric  acid  is  dropped  in  in  slight 
excess,  and  the  sulphate  of  lime  so  formed  separated  by  filtration. 
A  portion  of  the  filtered  fluid  is  then  distilled  off,  water  added, 
and  the  rest  of  the  spirit  driven  off  by  evaporation.  Carbonate 
of  potash  is  now  added  to  precipitate  the  alkaloid,  which  is  to  be 
collected,  dried,  and  again  dissolved  in  alcohol  ;  water  is  again 
added,  and  it  is  lastly  evaporated  and  crystallized.  1000  parts 
of  root  arc  stated  to  yield  three  of  the  alkaloid  (vide  Brandes' 
Chemistry.) 
Now  as  this  is  at  the  best  a  very  tedious  process,  as  well  as 
expensive  on  account  of  the  time  and  spirit  which  are  consumed, 
perhaps  I  may  be  pardoned  for  offering  a  more  simple  but  equally 
efficacious  one  to  the  notice  of  this  Society.  It  nearly  resembles 
the  original  method  of  M.  Brandes,  the  discoverer  of  the  sub- 
stance in  question,  but  differs  from  it  in  the  circumstance  that  he 
precipitated  the  atropine  with  liquor  potassge,  I  with  liquor 
ammonise. 
A  pound  of  the  dry  leaves  of  the  belladonna  are  to  be  boiled 
in  distilled  water  sufficient  to  cover  them,  for  two  hours,  and  the 
decoction  strained  off  through  a  coarse  cloth  into  a  large  preci- 
pitating jar.  The  leaves  are  again  boiled  in  a  second  water  and 
the  decoctions  mixed,  to  which  two  drachms  of  strong  sulphuric 
acid  are  now  added ;  the  vegetable  albumen  is  precipitated,  and 
the  clear  liquor  is  drawn  off  with  a  syphon  to  a  filter.  A  clear 
sherry-colored  solution  comes  through,  which  is  either  decom- 
posed by  passing  gaseous  ammonia  through  it,  or  by  suspending 
in  it  a  lump  of  sesquicarbonate  of  ammonia.  In  either  .case,  the 
color  becomes  changed  to  black,  and  crystals  of  atropine  are 
slowly  formed.  At  the  expiration  of  a  day  or  so,  the  supernatant 
liquor  may  be  drawn  off  with  a  syphon,  and  the  crystals  thrown 
on  a  filter  to  dry. 
To  decolorise  them,  about  an  ounce  of  spirit  of  ammonia  may 
be  poured  on  the  filter,  which  washes  away  most  of  the  coloring 
matter,  leaving  the  crystals  moderately  white. 
By  this  process  I  have  generally  obtained  about  forty  grains 
from  a  pound  (avoirdupois)  of  leaves,  which  gives  5  J  grs.  to  1000 
of  plant,  instead  of  3  to  1000. 
