A TEST FOR CINCHONINE IN QUININE. 231 
ART. XLVL— ON A METHOD OF DETECTING THE PRE- 
SENCE OF SULPHATE OF CINCHONINE IN THE SULPHATE 
OF QUININE, AND OF ESTIMATING ITS AMOUNT. 
By 0. Henri. 
Having been requested to analyse several samples of 
sulphate of quinine from various sources, with a view to 
detect any sulphate of cinchonine, supposed to exist in them 
to a considerable amount, I had occasion to make various 
experiments, the publication of which may prove useful. 
As is well known, cinchonine always accompanies qui- 
nine in the barks. Although its medical properties have a 
certain analogy with those of quinine, they do not possess 
the same energy; and, moreover, as the proportions of sul- 
phate of cinchonine mixed with that of quinine are variable, 
and, as I have had occasion to find, frequently vary con- 
siderably, the sulphate of quinine can no longer possess the 
same intensity in its medical action nor the same constancy 
in its effects. In the preparation on a large scale of the 
sulphate of quinine, that of cinchonine, being far more solu- 
ble, remains in the mother-ley, and mere traces can adhere 
to the former. Now when we find sulphate of cinchonine, 
to the amount of 4, 6, 8, 10, 15, &c. per cent., there can be 
no doubt that it has been added fraudulently. 
To detect the presence of sulphate of cinchonine in sul- 
phate of quinine, I first tried the processes proposed by Mr. 
Calvert and by M. Oppermann. The first of these pro- 
cesses consists in adding to a solution of the suspected sul- 
phate of quinine a solution of chloride of lime (hypochlo- 
rite.) The sulphate of quinine gives at first a white pre- 
cipitate, but the deposit dissolves in an access of the reagent ; 
whilst the sulphate of cinchonine yields, according to the 
author^ an abundant precipitate, which is permanent. In 
the second process, that of M. Oppermann, a suitable 
