QUANTITATIVE ESTIMATION OF THE ALKALOIDS. 69 
the structure of true Cinchona barks, but contain, however, no 
cinchona bases, but paricine. Cinchona nova surinamensis does 
not give the red tar, which, however, is afforded by Cinchona 
cuprea. 
Hesse renders Grahe’s test more delicate by extracting with 
alcohol the bark to be tested, drying the tincture with an appropriate 
amount of powder of the same bark, and first heating the latter 
product. 
SECTION XIV. . 
QUANTITATIVE ESTIMATION OF THE ALKALOIDS. 
The estimation of the alkaloids may be quite satisfactorily ac- 
complished by the following method :— 
I. Twenty grams of a well selected, average specimen of the bark 
is very finely powdered, moistened with ammonia water,’ and, after. 
standing for an hour, mixed with 80 grams of hot water; it is then 
allowed to cool, subsequently intimately mixed with milk of lime 
(prepared by triturating 5 grams of dry caustic lime with 50 grams 
of water,) and the mixture evaporated upon a water-bath until it 
is uniformly converted into small, somewhat moist, crumb-like 
particles. This is then transferred toa cylindrical glass tube (see 
figure), which at A is 2.5 centimeters (1 inch) wide, and 
from A to B 16 centimeters (6.4 inches) long. AtBa § 
small brass sieve is inserted, upon which a disc of filtering gig 
paper is secured by means of a bunch of loose cotton. ,/7/7 
The powder having been quite compactly adjusted upon 
the cotton, it is again covered at A, as in B, with a little | | 
cotton; the latter having been previously employed for a gi 
removing the last traces of the powdered bark from the fee 
capsule. At Z, a tightly-fitting cork is inserted, which is 
penetrated by the tube &, and connected with an invert- 
ed, small, glass condenser. The lower end of the appa- 
ratus, C, is tightly connected, by means of a cork, with 
the flask X, containing about 100 cubic centimeters of 
ether. The flask is then heated by means of a constantly ae 
supplied water-bath; and in the same degree as the s fas 
vapors of ether are expelled through D, they become 
again condensed in the condenser—the liquid dropping ¢\! 
through the tube R upon the powder at A, penetrating f/f 
the entire column of powder 4 JZ, and flowing at tosab i jy 
urated with alkaloid, into the flask A. To effect the com- 
plete exhaustion of the bark by the ether, the operation 
a "This effects a remarkable swelling and disintegration of the tissue. 
