124 
CONSTITUENTS  OP  COCA  LEAVES. 
to  a  greyish  white  transparent  mass  which  crystallizes  after  some 
days ;  the  solution  crystallizes  in  long,  tender,  radiating  crystals. 
The  sulphate  and  nitrate  dry  to  an  amorphous  colorless  mass, 
which  gradually  changes  to  crystals,  the  latter  with  great  diffi- 
culty. The  acetate  readily  assumes  the  form  of  a  crystalline, 
sometimes  herbaceous,  looking  mass. 
The  following  is  the  behaviour  of  a  diluted  solution  the 
hydrochlorate  to  reagents  : 
Fixed  alkalies :  a  white  precipitate,  slowly  soluble  in  a  large 
excess. 
Ammonia  and  carbonate  of  ammonia  :  the  same  precipitate, 
readily  soluble  in  excess. 
Carbonate  of  soda:  white  precipitate,  insoluble  in  excess^ 
becoming  crystalline. 
Sulphocyanide  of  potassium :  a  slight  turbidity, 
Protochloride  of  tin  :  a  white  curdy  precipitate,  soluble  in 
much  nitric  acid. 
Nitropicric  acid  :  a  pulverulent  sulphur-yellow  precipitate, 
becoming  resinous. 
Terchloride  of  gold,  even  in  the  most  diluted  solutions :  a  vo- 
luminous light  yellow  precipitate,  becoming  flocculent,  soluble  in 
the  heated  mother-liquor  and  crystallizing  on  cooling  in  beauti- 
ful yellow  scales,  resembling  iodoform;  it  crystallizes  from  hot 
alcohol  in  golden  yellow  scales  or  in  a  dense  granular  powder. 
Bichloride  of  platinum  :  a  dirty  greyish  yellow  precipitate, 
becoming  crystalline,  soluble  on  heating,  scarcely  soluble  in  mu- 
riatic acid. 
Tannin  :  a  very  slight  turbidity  ;  in  the  presence  of  muriatic 
acid  a  voluminous  pearly  white  precipitate,  shrinking  and  be- 
coming resinous  in  appearance. 
Bichloride  of  mercury  :  a  voluminous,  soon  flocculent  precipi- 
tate, soluble  in  muriatic  acid  and  in  chloride  of  limmonia.  It 
does  not  crystallize  from  its  solution  in  alcohol. 
lodo-hydrargyrate  of  potassium  :  a  curdy  white  precipitate, 
soluble  in  muriatic  acid  and  chloride  of  ammonium. 
Molybdate  of  ammonia  in  the  most  dilute  solutions  :  a  volumi- 
nous yellowish  white  precipitate. 
Iodine  :  a  kermes  brown  precipitate. 
Iodide  of  potassium  :  scarcely  a  faint  turbidity  :  when  con- 
