414 Proceeding's of* the Royal Society of Edinburgh. 



kind-hearted conduct, and cheerful conciliatory behaviour of Mr Richard 

 Cunningham, Colonial Botanist in New South Wales, has not been able 

 to protect him from the ferocious hostility of excited savages, and, we 

 have reason to believe, I fear almost from official authority, that he has 

 suffered a violent death when with an exploring party in the interior of 

 New Holland ; — a party which we know by letters from himself he joined 

 with the warmest anticipations of contributing largely to our knowledge 

 of Australian vegetation. Within two years, Douglas has been lost by 



an attack from a wild bull — Drummond, we believe, from climate and 



Cunningham, from what is worse than both, and less under restraint than 

 either, the madness of his fellow men. 



Proceedings of the Royal Society of Edinburgh. 



1825, December 7.— Dr Hope, V. P. in the Chair. The fol- 

 lowing communications were read : — 



1. On the Poisonous Properties of Hemlock, and its lately 

 discovered alkaloid, Conia. By Dr Christison. 



The author commenced by stuting, that he had repeated the 

 greater part of the analysis of hemlock lately executed by Profes- 

 sor Geiger of Heidelberg, and had obtained precisely the same re- 

 sults. According to his analysis, hemlock contains a peculiar prin- 

 ciple, alkaloidal in its nature, but differing from the previously disco- 

 vered alkaloids in its form, which is that of an oily-like liquid, vo- 

 latile at a moderate elevation of temperature, and capable of being 

 readily distilled over with water. It neutralizes acids, without 

 however forming crystallizable salts. It contains a considerable 

 proportion of azote. It quickly undergoes decomposition when ex- 

 posed to the air, giving out ammonia, and becoming a dark, resin- 

 ous-like substance. 



The discoverer inferred, from a few experiments chiefly made 

 on birds, that this principle, which may be termed Conia^ from the 

 genus of plant whence it is obtained, possesses active poisonous 

 properties ; that it produces coma, convulsions, and depressed ac- 

 tion or even paralysis of the heart ; and that its poisonous qualities 

 are greatly impaired by combination with acids. The author, how- 

 ever, has been led to conclude, from an extensive set of experi- 

 ments on the higher orders of animals, — that the effects of Conia on 

 the body are increased rather than diminished by neutralization 

 with an acid, such as the muriatic ; that it does not produce coma 

 when administered either free or combined ; that it does not act at 

 all on the heart ; that it possesses a local irritant action, and that 

 its remote action consists simply in the productiou of swiftly in- 

 creasing paralysis of the muscles, ending fatally by asphyxia from 

 palsy of the muscles of respiration. He farther found it to be a 

 poison of exceeding activity, scarcely inferior indeed in that respect 

 to hydrocyanic acid. Two drops applied to a wound, or introduced 

 into the eye of a dog, rabbit, or cat, will sometimes occasion death 

 in ninety seconds ; and the same quantity injected in the form of 



