''^'"AprifTssT™'}      Researches  on  the  Cinchona  Alkaloids.  165 
upon  the  addition  of  ammonia  or  caustic  soda,  a  white  voluminous 
precipitate,  which  consists  at  first  of  amorphous  flakes,  but  afterwards 
-becomes  crystalline.    The  acid  sulphate  is  obtained  by  dissolving  the 
Ibase  in  dilute  sulphuric  acid,  and  evaporating  at  about  60°C.;  it  forms 
delicate  concentrically  grouped  needles,  which  are  rather  diflicultly 
soluble  in  cold  water. 
The  dichlor hydrate  is  obtained  by  the  direct  evaporation  of  the  con- 
tents of  the  tube,  recrystallized  from  a  very  small  amount  of  water, 
:and  then  separated  from  the  motlier  liquid  by  placing  it  between  bibu- 
lous paper,  which  should  be  repeatedly  renewed.    It  is  quite  hygro- 
:SCopic;  dried  in  the  exsiccator,  it  still  lost  a  little  water  at  120  to 
130°C. 
The  eldoroplatinate  is  a  dark  yellow,  amorphous,  flocculent  precipi- 
tate. 
Hydrochlorapocinchonia,  C19H23CIN2O,  is  formed  on  treating  apocin- 
chonia,  cinchoniaor  certain  salts  of  the  latter,  with  highly  concentrated 
liydrochloric  acid;  traces  of  diapocinchonia  are  also  produced  and 
unchanged  apocinchonia  remain  dissolved  on  mixing  the  contents  of 
the  tube  with  half  the  volume  of  water,  while  the  dichlorhydrate  of 
^hydrochlorapocinchonia  separates,  and  may  be  purified  by  recrystal- 
lizing  from  water  containing  hydrochloric  acid.  If  the  pure  salt  be 
then  dissolved  in  boiling  dilute  alcohol,  and  a  sufficient  amount  of 
ammonia  added  upon  cooling,  the  base  is  obtained  in  delicate,  colorless, 
a,nhydrous  needles.  It  melts  at  197°C.  (uncorr.),  is  sparingly  soluble 
in  ether,  chloroform  and  absolute  alcohol,  almost  insoluble  iii  water, 
and  quite  insoluble  in  caustic  soda.  Its  alcoholic  solution  reacts  feebly 
alkaline,  and  is  dextrogyrate,  in  alcohol  ^205*4°,  and  in  water  with 
3HC1  -f  208*0°.  It  dissolves  very  readily  in  dilute  acids,  and  is  pre- 
cipitated from  these  solutions  by  an  excess  of  ammonia  or  sodium 
hydrate  in  white,  voluminous  flakes,  which  soon  become  crystalline  ; 
with  the  acids  it  forms  apparently  only  acid  salts. 
The  dichlorhydrate  forms  colorless,  shining,  pointed,  six-sided  prisms, 
dissolves  readily  in  pure  water,  but  slightly  in  water  containing  hydro- 
chloric acid,  and  contains  no  water  of  crystallization. 
The  cliloroplaiinate  is  a  dark  yellow,  amorphous,  flocculent  precipi- 
tate. 
V.  Action  of  Acetic  Anhydride  upon  the  hydrochlorapo-hases. — It 
remained  only  to  examine  whether  the  hydroxyl  groups  contained  in 
ih^  apo-bases  are  transferred  unchanged  by  the  conversion  of  the  latter 
