240 QUIXINE AND CINCHONINE. 
difficulty. On cautiously heating some in a glass tube, a 
sublimate of crystals wasobtained,Vhich were exactly like 
those formed under similar circumstances from cinchonine. 
Tiie peculiar odour of quinoile,. which is perceived on heat- 
ing crystallized and amorphous quinine, could not be ob- 
served. From solutions of the same amount of the two 
substances in muriatic acid, the author obtained the same 
weight of the insoluble platinum double salt, when an ex- 
cess of chloride of platinum was poured into the solutions, 
which precipitated the whole of the organic substance from 
the liquids; however, the salts differed somewhat in their 
state of aggregation ; that from qninoidine was of a bright 
yellow and loose, that from cinchonine was darker and 
more pulverulent crystalline. The double salt from cincho- 
nine left on ignition 24.15 per cent., that prepared from qui- 
noidine 23.35 per cent, of platinum. The author is thence 
led to believe that quinoidine (amorphous quinine and cin- 
chonine) is formed by the action of acids upon the alka- 
loids in their ])reparation. He believes that quinine 
is not so readily converted by acids into amorphous 
quinine, as cinchonine, and a quinoidine containing but 
little or no amorphous quinine, is probably obtained in 
})reparing a sulphate of quinine from barks containing both 
alkaloids. ^ , 
Hyposulphite of soda immediately precipitates hyposul- 
phite of quinine, in the form of a dazzling white crystalline 
precipitate, from the solution of the muriate of quinine: 
cinchonine separates under similar circumstances in four- 
sided needles. Both salts disengage sulphuretted hydrogen 
and sulphurous acid, when concentrated sulphuric is poured 
over them. When treated with dilute sulphuric acid, they 
are converted into sulphates, with evolution of sulphurous 
acid and elimination of sulphur. The amorphous alkaloids, 
when saturated with muriatic acid, do not yield these pre- 
cipitates. The author turns this reaction to account in de- 
