192 



ALKALOIDS. 



alkaloid ' of cinchona bark. The latter found 1 part of cincho- 

 nine dissolve in 1,100 parts of spirit of that strength, but, as the 

 solution obtained in the separation of the alkaloids is not a 

 saturated one, he recommends the addition of 0*0002 gram 

 cinchonine for every cc. of such spirit used. He also found pure 

 ether (free from water and alcohol) very suitable for the same 

 purpose, as it dissolves so little cinchonine that a correction is 

 scarcely necessary. The mixture of both alkaloids must be com- 

 pletely dried in the water-bath, and then very carefully powdered. 

 The separation of two alkaloids by means of ether may also be 

 accomplished by allowing the ethereal solution of both to evaporate 



Fig. 8. 



gradually, and, if one should separate in crystals, removing the 

 other by slow washing with ether in the form of vapour. By this 

 method I succeeded with Marquis l in separating delphinine from 

 delphindidine in perfectly colourless crystals. 



The flask , containing the mixed alkaloids (Fig. 8, A), was 

 inverted in the wide-mouthed bottle, b, into which about 10 cc. 

 of pure ether had been poured. The apparatus was then allowed 

 to stand for several days at the ordinary temperature, during 

 which ether-vapour from 5 was continually condensing in a, and 

 dropping back into b } saturated with delphinoidine. 



The apparatus figured in 8 B, allows of the process being, to a 

 certain extent, regulated ; the funnel a, containing the flask, can 

 be raised or lowered at pleasure. 



1 Archiv f. exper. Pathol. iind Pharmacol. vii. 55, 1877. 



