ON THE PREPARATION OF QUINIA AND CINCHONIA. 199 
ART. XLVI1I. — ON THE PREPARATION OF QUINIA AND 
CINCHONIA. By M. F. C. Calvert, Preparateur du Cours de 
Chhnie, Applique an Jardin des Plants a Paris. 
M. Calvert remarks that similar amounts of the alkalies 
are not extracted with any regularity from equal weights of 
cinchona, although of the same quality of bark. This is 
due to the fact, that lime and the chloride of calcium are 
capable of dissolving quinia, and it is difficult to avoid using 
lime in excess. 
The same objection may be urged against caustic ammo- 
nia and potassa 3 but not against caustic soda, as this, when 
added in excess, dissolves neither quinia or cinchonia. Of 
this insolubility he satisfied himself by repeatedly precipi- 
tating mixed solutions of the sulphates of quinia and cincho- 
nia by caustic soda. The solutions, after filtration and satu- 
ration with hydrochloric acid, gave no indications of quinia 
with chlorine and ammonia. Similar solutions, treated in 
the same manner with soda and hydrochloric acid, gave no 
evidence of cinchonia with chloride of lime. He therefore 
concluded that the process of extracting these alkalies by 
lime was imperfect, and proposes that caustic soda be sub- 
stituted for it, as all the vegetable bases will certainly be 
precipitated by it — -an object of great importance to the 
manufacturer. 
As the adulteration of sulphate of quinia by sulphate of 
cinchonia is frequently practised, and not easily detected, it 
appeared advantageous to be able to employ tests by which 
this fraud could be easily discovered, M. Calvert recom- 
mends the seven following reagents for this purpose: 
1. The most approved is the chloride of lime. This pre- 
cipitates both sulphate of cinchonia and sulphate of quinia ; 
but, in excess, re-dissolves the quinia and not the cinchonia. 
