DEPORTMENT  OF  ALKALOIDS  WITH  REAGENTS,  ETC.  453 
of  the  bark  becomes  perceptible.  It  is  nearly  insoluble  in  cold 
water,  and  dissolves  only  with  exceeding  difficulty  in  hot  water  ; 
it  dissolves  sparingly  in  cold  dilute  spirit  of  wine,- more  readily 
in  hot  spirit  of  wine,  and  the  most  easily  in  absolute  alcohol. 
From  hot  alcoholic  solutions  the  greater  portion  of  the  dissolved 
cinchonia  separates,  upon  cooling,  in  a  crystalline  form.  Solu- 
tions of  cinchonia  taste  bitter  and  manifest  alkaline  reaction. 
Cinchonia  is  insoluble  in  ether. 
2.  Cinchonia  neutralizes  acids  completely.  The  salts  have  a 
bitter  taste  of  the  bark  ;  most  of  them  are  crystallizable ;  they 
are  generally  more  readily  soluble  in  water  and  spirit  of  wine 
than  the  corresponding  quinia  compounds.  Ether  fails  to  dis- 
solve them. 
3.  Cinchonia,  when  treated  cautiously,  fuses  without  loss  of 
water ;  subsequently  white  fumes  arise  which,  like  benzoic  acid, 
condense  upon  cold  substances  in  the  form  of  small,  brilliant 
needles  or  a  loose  sublimate,  a  peculiar  aromatic  odor  being 
exhaled  at  the  same  time.  If  the  operation  is  conducted  in  a 
stream  of  hydrogen  gas,  long,  brilliant  prisms  are  obtained. 
(Hlawety.) 
4.  Potassa,  ammonia  and  the  neutral  carbonates  of  the  alkalies 
produce,  in  solutions  of  salts  of  cinchonia,  a  white,  loose  precipi- 
tate of  cinchonia,  which  does  not  redissolve  in  an  excess  of  the 
precipitants.  If  the  solution  is  concentrated,  the  precipitate 
does  not  exhibit  a  distinctly  crystalline  appearance,  even  though 
viewed  through  a  lens  magnifying  200  times  ;  but  if  the  solution 
was  so  dilute  that  the  precipitate  formed  only  after  some  time, 
it  appears  under  the  microscope  to  consist  of  distinct  crystalline 
needles,  aggregated  into  star-shaped  tufts. 
5.  Bicarbonate  of  soda  and  bicarbonate  of  potassa  precipitate 
cinchonia  in  the  same  form  as  in  No.  4,  both  from  neutral  and 
acid  solutions,  but  not  so  completely  as  the  simple  carbonates  of 
the  alkalies.  In  solutions  containing  one  part  of  cinchonia  to 
200  parts  of  water  and  acid  the  precipitate  still  forms  immedi- 
ately ;  its  quantity  increases  after  standing  some  time. 
6.  Concentrated  sulphuric  acid  dissolves  cinchonia  to  a  color- 
less fluid,  which,  upon  application  of  heat,  first  acquires  a  brown, 
and  finally  a  black  color.    Addition  of  some  nitric  acid  leaves 
