^'^ASS^s''^']Chemical  Examination  of  Cincho-^inine.  147 
loids,"  rendered  it  obvious  to  us  that  it  was  obtained  by  precipitation 
from  saline  combination  by  means  of  an  alkaline  base.  If,  as  the  man- 
ufacturers claim,  the  article  in  question  is  composed  wholly  of  the  cin- 
chona alkaloids,  the  task  of  determining  the  nature  of  the  acid  which 
had  held  the  alkaloids  in  saline  combination,  and  of  the  alkali  with 
which  it  had  been  precipitated  from  solution,  would  have  been  a  hopeless 
one.  In  other  words,  cincho-quinine,  being  ivholly  composed  of  quinia, 
quinidia,  cinchonia,  cinchonidia,  and  certain  not  well  determined  alka- 
loidal  principles  of  bark,"  it  cannot  contain  sulphuric,  nitric,  hydro- 
chloric or  other  acid  ;  nor  soda,  potassa,  or  ammonia,  either  free  or  in 
saline  combination.  We  preferred,  however,  to  accept  the  evidence  of 
our  chemical  experiments  rather  than  the  assertion  of  the  manufactur- 
ers, and  propose  in  the  following  to  give  the  results  of  our 
QUALITATIVE   EXAMINATION  OF  CINCHO-QUININE. 
for  which  we  used  the  sample  described  as  :  Sample  No,  i. 
This  sample  possessed  slight  alkaline  reaction  ;  a  portion,  brought  in 
contact  with  moist  red  litmus,  restoring  the  red  color  to  blue. 
It  readily  dissolved  in  water,  acidulated  with  hydrochloric  acid,  form- 
ing, practically,  a  clear  solution.  The  solution,  so  obtained,  produced 
with  solution  of  chloride  of  barium  a  copious  precipitate,  which  was 
insoluble  in  hot  nitric  acid. 
Qualitative  result  No,  i  .—  Cincho-quinine  contains  sulphuric  acid  in  re- 
latively large  quantities. 
A  second  portion  of  cincho-quinine  was  digested  with  water  for  24 
hours,  and  the  solution  filtered  from  the  undissolved  portion.  The  sol- 
ution was  evaporated  to  dryness,  and  incinerated  in  a  platinum  capsule, 
during  which  process  the  considerable  residue  melted,  became  charred, 
and  was,  finally,  entirely  dissipated. 
^alitative  result  No.  2. — Cincho-quinine  does  not  contain  a  non-volatile 
base  or  compound. 
A  third  portion  was  treated  with  boiling  strong  alcohol,  the  solution 
filtered,  and  the  small  residue  thoroughly  washed  with  hot  alcohol. 
The  residue=y/.    The  filtrate=5. 
J. — The  residue  was  readily  soluble  in  water,  and  was  neutral  to  test 
paper.  Its  solution  was  not  precipitated  by  ammonia,  but  gave  an 
abundant  precipitate  with  chloride  of  barium,  which  was  not  redissolved 
by  hot  nitric  acid.  When  a  portion  of  the  solution  was  heated  in  a 
test  tube  with  solution  of  potassa,  the  vapor  evolved  restored  the  blue 
