384 Prof. Christ i son on the Poisonous Properties of Hemlock, 



and it was not till 1831 that its active principle was detected 

 and detached by P?*ofessor Geiger of Heidelberg, and proved 

 by him to be one of a new order of organic alkaloids, — not fixed 

 and crystalline like those previously known, such as morphia, 

 strychnia, cinchonia, and the like, but volatile and oleaginous in 

 their physical form.* Prior to this discovery, the knowledge 

 possessed of the physiological effects of hemlock was vague and 

 meagre ; and little has since been done to supply the defect. The 

 ideas entertained by the Greek and Roman naturalists and physi- 

 cians of the poisonous properties of the ancient xavaov or cicuta, were 

 for the most part contradictory or obscure. Their statements, how- 

 ever, were long adopted by modern physiologists without examina- 

 tion, and applied to the Conium maculatum, or spotted hemlock of 

 botanists ; and the small amount of original inquiry which has 

 been attempted by late experimentalists, has added little to 

 the previous stock of knowledge. It is surprising, however, 

 that some late researches were not carried farther than they have 

 been ; for it would appear scarcely possible for any accurate ob- 

 server to attend carefully to the phenomena produced by hem- 

 lock and its alkaloid in their action on the animal body, without 

 remarking that they are in many respects among the most inte- 

 resting and extraordinary of all poisons. 



These views, and the physiological facts to be subsequently 

 related, were brought under my notice during an attempt made 

 last autumn to repeat the analytic researches of Professor Geiger. 

 As these researches are too little known in this country, or indeed 

 out of Germany, and I have had occasion to confirm almost every 

 fact advanced by the Heidelberg Professor, I have thought it not 

 inopportune to reproduce here the general heads of his analysis, 

 as introductory to the principal object of this paper, — which is, 

 " The Poisonous Properties of Hemlock, and its Alkaloid Conia." 



A short time before the analysis of Professor Geiger, it was 



* Magazin fur Pharmacie, xxxv. 72 and 259. 



