1821.] M. Brandes on Atropium. 265 



often reaching down to the middle of the prism. These trian- 

 gular planes appear frequently on the crystals of sulphate of 

 atropium, and are distinguishable by their great lustre. 



The sulphate of atropium is soluble in four to five parts of cold 

 water ; it seems hkewise to be soluble in alcohol ; for when J. 

 had poured the remaining liquid from the crystals, and begun to 

 wash them with spirit of 90 per cent, alcohol, a quantity of the 

 salt seemed to disappear, and this cold solution in alcohol, when 

 ammonia was added, became milky by the precipitation of 

 atropium. 



It does not attract moisture from the air, when as much as 

 possible freed from its adhering sulphuric acid, but, on the con- 

 trary, it loses its water of crystallization. It is decomposed' 

 when strongly heated, and becomes black. 



The salts of barytes deprive this salt of its sulphuric acid, and 

 the carbonated as well as the pure alkalies precipitate atropium 

 from the solution. 



Composition of Sulphate of Atropium. — (A.) Three grains 

 were exposed on a watch glass to a moderate heat. While the 

 water of crystallization was evaporating, it became slowly opaque, 

 assumed a milk-white colour, on a few places it had begun to 

 blacken, and resembled enamel in appearance. When it had 

 ceased to lose weight by heat, the loss amounted very nearly to 

 three-fourths of a grain, or 25 per cent, which is to be considered 

 as water of crystallization. Ihe salt was only in a very slight 

 degree decomposed, and vv^as almost entirely soluble in water. 



(B.) Three grains of the same salt were dissolved in water, 

 and ammonia was added to the solution. The precipitate, when 

 collected on a filter, weighing 3^^ grs. washed and dried amounted 

 to a little more than 1^ gis. 



(C.) The filtered liquid from (B.) after being supersaturated 

 by acetic acid was mixed with a solution of muriate of barytes. 

 There was as much sulphate of barytes obtained after heating it 

 red, as would indicate almost 36 per cent, of sulphuric acid. 



The sulphate of atropium, therefore, is composed of 



Atropium 39 



Sulphuric acid 36 



Water 25 



Too [ 



I must confess I had some doubts as to the correctness of 

 this analysis, for on comparing it with that of the sulphate of 

 strychnium by Pelletier and Caventou, and that of sulphate 

 of picrotoxium by Boullay, and my own analysis of sulphate of 

 morphium, it appears that all these three alkaline substances are 

 very low in saturating power ; while the atropium would, accord- 

 ing to my analysis, neutralise a much larger quantity of sulphuric 



