QUANTITATIVE ESTIMATION OF THE ALKALOIDS. 75 
1. For Torart ALKALOIDS. 
IV. “Twenty grams of the cinchona, in very fine powder, and ° 
fully dried at 100° C. (212 F.), are thoroughly mixed with 5 grams 
of lime which has previously been made into a milk with 50 cubic 
centimeters of distilled water, and the mixture completely dried at 
a temperature not above 80° C. (176° F.). The dried mixture is 
digested with 200 cubic centimeters of alcohol, in a flask, near the 
temperature of boiling, for one hour, and, when cool, the mixture 
poured upon a filter of about 15 centimeters (6 inches) diameter. 
The flask is rinsed and the filter washed with 200 cubic centimeters 
of alcohol, used in several portions, and allowing the filter to drain 
after the use of each portion. To the filtered liquid enough diluted 
sulphuric acid is added to render the liquid acid to test-paper, any 
resulting precipitate (calcium sulphate) allowed to subside, the 
liquid decanted, in portions, upon a very small filter, and the residue 
and filter washed with small portions of alcohol. The filtrate is 
then distilled or evaporated, to expel all the alcohol, allowed to 
cool, passed through a small filter, and the latter washed _ with dis- 
tilled water, slightly acidulated with diluted sulphuric acid, until the 
washings are no longer made turbid by solution of sodium hydrate. 
To the filtered liquid, concentrated to the volume of about 50 cubic 
centimeters, when nearly cool, enough solution of sodium hydrate 
is added to render it strongly alkaline. . The precipitate is collected 
on a wetted filter, allowed to drain, and washed with small por- 
tions of distilled water (using as little as possible), until the wash- 
ings give but a slight turbidity with test-solution of barium chloride, 
and the filter drained by laying it upon blotting or filter papers 
until it is nearly dry. 3 is 
The precipitate is then carefully detached from the filter, and 
transferred to a weighed capsule ; the filter is washed with distilled 
water, acidulated with diluted sulphuric acid, the filtrate made alka- 
line with solution of sodium hydrate, and, if a precipitate results, 
this is washed on a very small filter, allowed to drain well, and also 
transferred to the capsule. The contents of the latter are now 
dried, at 100° C. (212° F.), to a constant weight, cooled in a dessi- 
cator, and weighed. The number of grams multiplied by 5 equals 
the percentage of total alkaloids in the cinchona.” _ | 
The U.S, Pharmacopeeia recognizes under “ Cinchona” the bark 
of any species of cinchona containing at least 3 per cent. of its 
peculiar alkaloids, while the “ Cinchona Flava” (Calisaya Bark) — 
and “Cinchona Rubra” (Red Bark) are required to contain at least 
2 per cent. of quinine. — oe 
