Am.  Jouk.  Pharm.  \ 
Jan.  1,  1873.  J 
New  Quinimetric  Process. 
29> 
after  which  the  mass  is  gently  pressed,  dried,  and  weighed.*  If  the 
mother-liquor  is  found  to  be  very  acid,  ammonia  in  slight  excess* 
should  be  added,  for  the  purpose  of  precipitating  the  rest  of  the'  qui- 
nia. The  other  alkaloids  remain  in  solution,  and  are  next  separated 
by  precipitation,  dried,  weighed  and  tested  with  washed  ether. 
This  process  is  simple  and  expeditious,  and  yields  good  results,  the 
quinia  being  obtained  in  a  colorless  state.  I  quote  the  following  in- 
stances of  its  working  : — (1).  A  mixture  was  taken  of  pure  sulphate  of* 
quinia,  0*60  ;  cinchonia,  0*20  ;  dilute  sulphuric  acid  (1  to  10),  10  c.c.  ; 
while  hot  I  poured,  by  means  of  a  pipette,  first  concentrated  and  then 
dilute  ammonia  nearly  to  saturation  :  result  obtained — sulphate  of 
quinia,  0*59 ;  cinchonia,  0-22.  (2).  Sulphate  of  quinia,  0*50 ;, 
cinchonia,  0.25  :  acid  at  yff,  10  c.  c,  found  sulphate  of  quinia  0*52  ;. 
cinchonia,  017.  A.  Yellow  cinchona  bark,  20  grms.  has  yielded  per 
1000,  by  the  use  of  Rabourdin's  modified  process  (see  Journ.  de 
Pharrnacie,  1861),  strongly-colored  crystalline  sulphate  of  quinia, 
23.00  ;  with  Le  Maitre's  process,  somewhat  yellow-colored  sulphate- 
of  quinia,  22.30  ;  with  my  process,  colorless  sulphate  of  quinia, 
26-55.  B.  Yellow  cinchona  bark,  same  quantity,  by  Rabourdin's. 
process,  strongly  colored  crystallised  sulphate  of  quinia  (per  1000), 
29-50  ;  Le  Maitre's  process,  yellow-colored  sulphate,  26*75  ;  my  pro- 
cess, colorless  sulphate,  31*25.  Trials  with  other  kind  of  bark  yielded 
similar  results,  but  I  should  mention  that  the  separation  of  the  qui- 
nia as  sulphate  only  succeeds  well  when  the  quantity  of  quinia  in* 
the  bark  greatly  exceeds  the  cinchonia. 
To  exhibit  the  effect  of  an  excess  of  cinchonia  I  quote  the  follow- 
ing: — Sulphate  of  quinia,  0.40;  cinchonia,  0*60;  acid  10  c.c.,' 
yielded — sulphate  of  quinia,  0.58  (mixed  with  cinchonia) ;  cincho- 
nia, 0*48 :  the  impure  sulphate  of  quinia  thus  obtained  may  be 
purified,  re-crystallised  and  tested  with  ether  and  ammonia. 
As  sulphate  of  quinia  is  completely  insoluble  in  a  solution  of 
sulphate  of  ammonia,  there  is  no  fear  of  any  of  the  sulphate  of  qui- 
nia being  left  in  the  mother-liquor  if  the  saturation  with  ammonia 
is  sufficiently  complete.  To  prove  this  experimentally,  take  a  small 
quantity  of  sulphate  of  quinia,  shake  it  up  in  a  test-tube  three  parts, 
filled  with  cold  distilled  water,  filter  and  add  to  the  filtrate  a  few  crys- 
*It  is  preferable  to  dry  at  100°,  and,  after  having  weighed,  to  add  the  12  per 
cent  of  water  lost  by  the  operation  ;  in  that  condition  it  contains  75  per  cent., 
quinia. 
