Dr. A. von Planta o)i the Constitution of Bebeerine. 115 



introduced into the water-bath, it at first loses weight, but after 

 a few hours begins to acquire a slight yellow coloui', and by re- 

 maining longer in the water-bath it passes gradually into a dark 

 brown, and now in place of losing, gradually increases in weight 

 as its colour becomes darker. This phsenomenon was obviously 

 dependent on a slowly advancing decomposition of the impurity 

 still retained by the base, and rendered it necessary to seek for 

 some other and better method of purification, such as might 

 permit a more intimate contact between the oxide of lead and 

 the matter which adheres with such obstinacy to the bebeerine. 

 And nothing seemed more likely to answer the purpose than to 

 mix both substances, bebeerine and oxide of lead, in solution, 

 and then to precipitate them simultaneously from the fluid. 



To this end the already partially pu^rified bebeerine was dis- 

 solved in acetic acid, in which, however, it proved not to be en- 

 tirely soluble, but left behind a not inconsiderable quantity of 

 organic matter. [Pwre bebeerine is easily and completely soluble 

 in acetic acid.] The filtered solution was mixed with an excess 

 of solution of acetate of lead, and caustic potash gradually added 

 so long as a precipitate of bebeerine and oxide of lead was ob- 

 tained. The precipitate was thoroughly washed with cold water, 

 extracted with absolute aether, and the extraction continued as 

 long as the aether, on distillation, continued to give a residue of 

 bebeerine in the form of a pale yellowish syrupy mass. The 

 method used for bringing this mass into a state in which it could 

 be easily washed and di-ied, was the same as that I had before 

 successfully employed for the preparation of aconitine, and de- 

 pends upon the behaviour of bebeerine with absolute alcohol, in 

 which it dissolves easily, and cold water, in which it is almost 

 totally insoluble. A concentrated solution of the syrupy mass 

 in absolute alcohol was poured, drop by drop, into a sufficient 

 quantity of water, which was kept in constant motion by stirring, 

 so as to prevent the precipitated bebeerine from getting into 

 lumps. In this way there is formed an abundant flocky preci- 

 pitate, which, when collected on a filter, washed, dried and pul- 

 verized, forms a perfectly white powder. If the process be re- 

 versed, and water poured into the alcoholic solution of bebeerine, 

 it is impossible to prevent its running into lumps, which prevents 

 the thorough washing of the precipitate. 



Bebeerine prepared by this process is a perfectly colourless 

 and inodorous powder, persistent in the air, and highly electrical. 

 Heated on the phitinuni knife it melts easily, and yields a coal, 

 which, though very difficultly combustible, at length disappears 

 without leaving a residue. Heated in the oil-bath, it fuses at the 

 temperature of 350° F. into a glassy mass, the weight of which is 

 the same as that of the substance dried at 250'^. It presents 



12 



