CINCHONA. : ORD. XIV. Rubdiacex. 33 
then obtains, by distillation, a brown viscid matter, which becomes brittle 
when cold, and is very bitter; this matter he digests in hot water, acidulated 
by sulphuric acid; and the liquor, when cold, gives pure sulphate of qui- 
nine, in the form of perfect white crystals. These crystals are soluble in 
boiling water, especially if it be weakly acidulated ; they are but little solu- 
ble in cold water, without the addition of an acid. We are told by Dr. 
Paris, that five or six drachms of the sulphate* may be obtained from two 
pounds of bark, by boiling it for half an hour, in sixteen pints of distilled 
water, acidulated with two fluid ounces of sulphuric acid. The quantity of 
lime necessary to be used is half a pound, or sufficient to render the solution 
of a dark brown, and to produce a reddish brown precipitate.+ 
Chemical Properties of Cinchonine and Quinine. Cinchonine is white, trans- 
lucent, crystallizable in needles, and soluble only in seven hundred parts of 
cold water. If dissolved in alcohol or an acid, its taste is powerfully bitter, 
and resembles that of the grey-bark. . Itis dissolved in very smal] quantities 
by the fixed or volatile oils, and sulphuric ether. _ With acids it forms salts 
which are more or less soluble. According to the analysis of Mr. Brande, 
cinchonine consists of about— 
CAsOON ee ee ee 80,20 
Nitroget oS ra ee eee 
Hiyvatogen. 2 re re ee ee 
99,90 
Quinine is white, incrystallizable ;{ it is as little soluble in water as cin- 
chonine, much more bitter to the taste, as are also most of its salts, which 
* Eight grains of which are equal to an ounce of bark. 
+ M. Robiquet, by adopting a somewhat different mode of aoudinis: obtained a sul- 
phate of quinine, the characters of which are different from those we have described. He 
obtained a sulphate, in solid transparent prisms, of a flattened, quadrangular form, and 
soluble even in cold water: by comparative trials he found also, that this difference arose 
from the prismatic sulphate being acid, and the other alkaline. He is satisfied of the 
stability of the characteristics ; for the salts preserve them without alteration after several 
crystallizations, although the sub-sulphate lost each time a small portion of its acid. 
t MM. Pelletier and Dumas have succeeded in giving to quinine a crystalline form 
by Sbatibaiens it to a state of fusion in vacuo, and allowing it to cool in a slow manner. 
Under this treatment, instead of preserving its resinous aspect and transparency, it con- 
tracts, becomes opaque, and forms at its surface centres of — which radiate 
on all sides ; the fracture of the mass is crystalline. 
VOL. V. r 
