384 Prof. Curistison on the Poisonous Properties of Hemlock, 
and it was not till 1831 that its active principle was detected 
and detached by Professor Gricer 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 zaveov 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 Coniwm 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 GricEr. 
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 Gricrr, it was 
* Magazin fiir Pharmacie, xxxv. 72 and 259. 
