MANUFACTURE OF QUININE. 79 
certain that by surface attraction no trace of iodosulphate of 
cinchonidine has adhered to the crystals of herapathite. After 
perfect cooling, the weight of the beaker is ascertained again, the 
crystals of herapathite carefully collected on a small filter, and the 
empty beaker again weighed. The difference in weight will indi- 
cate the amount of liquid, which is added to that of the first liquid, 
and from the sum of this addition the necessary correction is cal- 
culated. If the operation is effected at a temperature of 16° C. 
(60.8° F.), the weighed quantity of the two liquids will indicate the 
correction if multiplied by 0.125 and divided by roo. If the tem- 
perature be lower or higher, the solubility of herapathite at that 
temperature must be ascertained by experiment, which can easily 
be performed by a standard solution of hyposulphite (thiosulphate) 
of sodium, as 21.58 parts of iodine found by this reagent indicate 
100 parts of herapathite. The herapathite collected on the filter 
is thoroughly washed with a saturated alcoholic solution of pure 
herapathite, and after this washing is completed the liquid retained 
by the crystals is expelled as muchas possible by slightly knocking 
the side of the funnel. The filter is then taken from the funnel 
and laid upon blotting paper, often renewed, to take away as 
quickly as possible the still adhering liquid. As soon as the filter 
is air-dry, the crystals of herapathite can be completely removed 
from the filter and dried on a water-bath in one of a couple of large 
watch-glasses closing tightly upon each other, so that the weight of 
the substance contained in the glass may be taken without the 
access of the air. If, after repeatedly weighing, the weight remains 
constant, it is noted, and to itis added the product of the calculated 
correction. The sum of this addition is the total amount of iodo- 
sulphate of quinine obtained from the mixed alkaloids subjected to 
the operation, and from this weight the amount of quinine can be 
calculated from Jérgensen’s formula: 4C,,H,,N,O, + 3H,SO, + 
2HI + 1,. According to this formula one part of herapathite, dried 
at 100° C, (212° F.), represents 0.55055 parts of pure anhydrous 
quinine. 
SECTION XV. 
MANUFACTURE OF QUININE. 
The preparation of quinine and the other alkaloids on a manu- 
facturing scale consists likewise in separating them from the com- 
pounds in which they are contained in the bark, by means of lime. 
From the moist mixture, containing lime, the bases are extracted by 
means of warm shale oil, brown coal-tar oil, or petroleum of a low 
