14G Analysis of the Atropa Belladonna, 



up, and exhales pungent acrid vapours, in which ammonia 

 cannot be distinguished. 



We may conclude from the effects produced in the so- 

 lution oF the extract of belladonna by the various re-agents 

 above employed .- 1st, that it contains a free acid; 2d, an al- 

 kaline muriate; 3d, a small quantity of an ammoniacal salt. 



The nature of the acid which exists in this substance 

 can be nothing but acetic acid, since the sulphuric acid 

 develops the smell of it, and the acetate of lead does not 

 form any precipitate in it, which would take place if it were 

 malic, tariarous, or oxalic acid. A part of this acid ought 

 to be combined with the potash, and it is without doubt 

 this combination which communicates to the extractive 

 mass the property of attracting humidity from the air. 



But it is neither these salts nor these acids which give 

 poisonous qualities to the matter; these certainly reside in 

 the vegetable substance itself: what then is the order of 

 composition, which thus forms out of the same principles 

 both our food and our poison ? This is a difficulty which 

 chemistry has not yet overcome, and unfortunately it is 

 behind this barrier that secrets the most important to hu- 

 manity are retained. 



For want of the means of ascertaining accurately the dif- 

 ferences which exist between vegetable compounds whose 

 properties are diametrically opposite, we shall have recourse 

 to their effects. , 



One of the means resorted to as the most proper for 

 guiding us as to the nature of the substance of belladonna 

 •soluble m alcohol, was its decompostion by means of heat. I 

 'introduced therefore two grammes and seven-tenths into a 

 gla*s retort, and administered the heat by degrees 3 until the 

 water of solution was distilled: there passed over a yellow 

 ammoniacal liquid, afterwards a thick oil which had a very 

 singular disagreeable smell. 



The examination of the liquid product enabled me to 

 •recognise a good deal of ammonia, partly free and partly 

 combined ; for the addition of some drops of caustic potash 

 rendered the ammoniacal smell much stronger, and the oil 

 was thick, black, and very acrid. 



The charcoal remaining in the retort weighed one gram- 

 me, and had an alkaline and prussialed taste: when washed 

 in boiling water, it yielded a ley which when mixed with 

 •sulphate of iron furnished a quantity of prussian blue very 

 considerable with respect to trie small quantity of matter 

 xM*mloved. ' This charcoal after having been lixiviated and 

 dried still weighed -fa of a gramme. 



The 



