J 82 1 .] M, Branded on Atropium. 2^ 



Article V. 



On Atropium, a new Alkaline Body in the Leaves of Atropa 

 Belladonna, By M.Rudolph Brandes* 



M.Brandes first states, with reference to another paper of 

 his which has not conrie to hand, that he found, in an analysis of 

 the leaves of atropa belladonna, that pure alkalies precipitated a 

 substance from the decoction of them which had alkaline 

 properties like morphium. He then boiled a filtered decoction 

 of the leaves of atropa belladonna with pure magnesia, washed 

 the powder thus obtained with water, and boiled it in alcohol^ 

 This hot solution in alcohol had likewise alkaline properties, and 

 proves, therefore, that they were not to be ascribed to the alkali 

 employed in the first experiment. He then goes on to state the 

 following experiments : 



I boiled two pounds of dried leaves of atropa belladonna in a 

 sufficient quantity of water, pressed the decoction out, and 

 ' boiled the remaining leaves again in water. The decoctions 

 were mixed, and I added some sulphuric acid in order to throw 

 down the albumen and similar bodies ; the solution is thus ren^ 

 dered thinner, and passes more readily through the filter. The 

 decoction was then supersaturated with potash, by which I 

 obtained a precipitate that, when washed with pure water and 

 dried, weighed 89 grs. It consisted of small crystals, from which, 

 by repeated solution in acids, and precipitation by alkalies, the new 

 alkahne substance, atropium, was obtained in a state of purity. 



Properties of Atropium. — The external appearance of atropium. 

 varies considerably according to the different methods by which 

 it is obtained. When precipitated from the decoction of the 

 herb by a solution of potash, it appears in the form of very small 

 short crystals, constituting a sandy powder. When thrown 

 down by ammonia from an aqueous solution of its salts, it 

 appears in flakes like wax, if the solution is much diluted ; if 

 concentrated, it is gelatinous like' precipitated alumina; when 

 obtained by cooling of a hot solution in alcohol, it crystahizes in 

 long, acicular, transparent, brilliant crystals, often exceeding one 

 inch in length, which are sometimes feathery ; at other times 

 starhke in appearance, and sometimes they are single crystals. 

 Atropium, however, is only obtained in such a crystalline state 

 when rendered perfectly pure by repeated solution in muriatic 

 acid, and precipitation by ammonia : a solution of impure 

 atropium which I made by boiling the decoction of the leaves 

 of atropa belladonna with magnesia, and dissolving the precipi- 

 tated alkali in hot alcohol, has not, during half a year, deposited 

 any crystals but merely flakes. 



^ Rom Schweigger'g Journal, vol xxviii. p. 1. 



