330 



OMISSIOISTS Al^D ERRATA. 



Acouitill. — Dr. C. H. A. Wright lias sliown that the use of 

 alcohol acidulated with a mineral acid, for exhausting the root of 

 Aconite, causes an alteration of the alkaloids originally })resent ; 

 hence it is recommended, according to Duquesnel's method, to 

 percolate by alcohol acidulated with tartaric acid, to evaporate at 

 a low temperature, or, better still, in vacuo, to crystallise from 

 ether after the sepai'ation of the base by sodium-carbonate, and to 

 purify by conversion into a crystalline salt, for which purpose the 

 hydrobromide is well fitted. Dr. Wright's formula for pure 

 Aconitin=C33 H43 NO12.— (Blackett). 



AlstOlliu. — Alkaloid of the bark of Alstonia constricta, F. v. M- 

 Obtained by treating the alcoholic extract with Avater and a little 

 hydrochloric acid, adding to the filtered solution a small excess of 

 ammonia, dissolving the separated flocks in ether, evapoi-ating the 

 ethereous solution, and purifying the remaining- A. by dissolving 

 again in dilute acid and repeating the above process. — Orange 

 yellow, brittle, pellucid mass, of very bitter taste, melts below 

 100°, and is cai'bonised in higher temperatures; dissolves easily 

 in alcohol, ether, and dilute acids, spaiingly in water. All its 

 solutions in the dilute state exhibit a sti-ong blue fluorescence, 

 which is not affected by acids or alkalies. Its alcoholic solution 

 has a slightly alkaline reaction. Alstonin combines with acids, 

 but does not completely neutralise them. Hydrochloric and other 

 strong acids, also alkalies, decompose it partly on eva]:)oration in 

 the water-bath to a dark-coloui-ed acid substance. The hydi'O- 

 chloride of A. gives jn-ecipitates with the chloi'ides of platinum 

 and mercury, the iodides of potassio-mercury and of potassio- 

 bismuth, bi-iodide of potassium, the phospho-molybdate and the 

 phospho-tungstate of soda, bichromate of })otash, picric acid, and 

 by the alkalies and alkaline carbonates. Tannic acid does not 

 precipitate the hydrochloiide, but does so the acetate and the pure 

 base. Concentrated nitric acid dissolves A. with crimson colour, 

 yellow on warming; sulphuric acid reddish brown, afterwards 

 dirty green ; hydrochloric only effects a yellowish solution. 

 Alstonin differs from Ditamin chiefly by its behaAiour towards 



