The Adulteration of Quinine. 
301 
Fifty grains more well boiled in four ounces of water, and the 
clear solution poured off, the precipitate was again boiled in 
a fresh portion of water ; washed on a filter and dried ; the 
precipitate weighed grains. 
In water acidulated with sulphuric acid, nearly the whole 
dissolved on boiling it a few minutes. 
With a view to ascertain the precise quantity of pure qui- 
nine contained in the article, 50 grains were dissolved in boil- 
ing water ; when nearly cold, water of caustic ammonia was 
added until all the quinine was precipitated, which being col- 
lected on a filter, washed with a small quantity of water, and 
carefully dried with a gentle heat gave 33^ grains, indicating 
84 per cent, sulphate of quinine, or 16 of impurities. Taking 
M. Robiquet's analyses of sulphate of quinine as correct, 
which the decomposition of 3 or 4 different portions justify 
me in doing, the two articles will stand as follows : — 
Pure Sulphate Quinine. Delondre's. 
It is gratifying to me to learn, that my friend Mr. Durand, 
to whom a portion of this article was sent, confirms the re- 
sults of most of my experiments. 
While manufacturers or venders, can be tempted by the 
hope of gain to vend impure or adulterated articles, the only 
remedy for the evil must be found with the retail apothecary, 
through whose hands the articles finally pass: let him ac- 
quaint himself with, and apply, the test, and the evil cannot 
long exist. To enable every apothecary to test the purity of 
sulphate of quinine, I would suggest the following simple ex- 
periments: First, try its solubility in boiling alcohol, 50 grains 
if pure will dissolve perfectly in one ounce of boiling alcohol. 
Should it be found to dissolve perfectly, and not. speedily depo- 
site crystals, the result is satisfactory. Then let 50 grains more 
Quinine, 79 
Acid, 11 
Water, 10 
Quinine, 67 
Acid, 9.3 
Water, 8.5 
Impurities, 15.2 
100 
100 
