ANALYSIS OF HEDGE HYSSOP; gQ^ 



water in so large proportion as it exists in the juice of the 

 plant. 



The consistence of this sort of resinoid is that of a soft Its properties, 

 paste: but if it be exposed some time to the open air, it 

 dries, and becomes friable. Its extraordinarily bitter taste 

 has nutch resemblance to that of colocynth, thoughthe plant 

 that furnishes it is not of the same family : it differs from it 

 however by a saccharine taste preceding the bitter. 



After having expressed the juice of the hedge hyssop, and Solid substance 

 exhausted the magma by water and alcohol, I left it three g^^j^j^ij^e^^ 

 days in diluted nitric acid. I then pressed the acid strongly 

 through a cloth, washed the magma with water, and added 

 ammonia to the united liquors, in which it formed a floccu- 

 lent yellow precipitate. As this precipitate showed some 

 traces of vegetable matter, I calcined it lightly ; after which 

 it dissolved with effervescence in muriatic acid, and from the 

 solution ammonia threw down a yellow precipitate which 

 consisted of phosphate of lime, and oxide of iron. It also 

 yielded, on the addition of oxalic acid, a certain quantity 

 of oxalate of lime. 



The magma of the hedge-hyssop still contained oxalate of 

 lime, phosphate of lime, and iron, which also was probably 

 united with phosphoric acid. 



Lastly, the magma, having been burned, left ashes con- 

 sisting for the most part of silex, with a little calcareous 

 earth and iron. 



From what has been said there appears no doubt, that The active 

 the active and cathartic principle of hedge hyssop is the sub- P""ciple. 

 stance soluble in alcohol, which I have called a resinoid ; 

 since it is the only one in it, that has any taste. Its solu- 

 bility in water, which is increased by the gum and the salts 

 that accompany it, explain why the infusion, and still 

 more the decoction of the plant, are purgative, and even 

 drastic. 



The violent action of hedge hyssop on the animal economy Formerly pro- 

 has long been known to physicians; and this no doubt is hibited, for its 



V 10161106 



the reason, why the sale of this plant has formerly been pro. 

 hibited. This prudent measure, which has fallen into dis- 

 use, ought to be revived ; for accidents frequently happen 

 Supplement. — Vol. XXX.. B b from 



