On the Coneine of Geiger. 
245 
to atmospheric variations, disengage ammonia when treated 
with potash. 
2d. That the odorous principle which accompanies the 
ammonia, is not alkaline, that it does not saturate acids, and 
unites with charcoal like a colouring matter. 
3d. That the coneine of M. Geiger owes its alkalinity to 
ammonia. 
4th. That if the active principle of conium is an alcaloid, it 
is still to be discovered. 
5th. That the extrication of carbonic acid, resulting from 
the action of potash on the extract, by the addition of nitric 
acid, and the disengagement of ammonia, indicates that these 
bodies are formed under the influence of the potash, at the ex- 
pense of a peculiar body, as yet unknown. 
6th. That the alteration of the acetic extract of conium 
tends to prove that the acetic acid, after having taken up this 
principle, and destroyed its natural combinations, again 
abandons it, from its property of forming unstable combina- 
tions only, and that this body, thus set at liberty, is decom- 
posed. 
7th. That the action of hydrochloric and acetic acids on 
the extracts, are thus explained. 
8th. That the seeds have less activity than the plant. 
9th. That the extract without chlorophylline, and the alco- 
holic extract prepared with fresh conium, and alcohol at 35° B. 
are the most active preparations. 
10th. That the method of M. Caventou is liable to destroy 
some of the properties of the conium. 
The advantage of his extract, if its greater efficacy be ad- 
mitted, would reside in the combination of the active, volatile 
principle with the acetic acid. If this be the case, it is evi- 
dent that the fresh plant is preferable to the dried, and that 
the whole preparation might be reduced to pounding the 
plant, extracting the juice, freeing it from the chlorophylline 
and albumine, adding acetic acid 3i. to the lb. evaporating 
and preserving the extract in a close vessel. This mode of 
preservation ought to be adopted with all extracts which 
