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Selected Articles. 
plant to an acid which retains it on a distillation with water 
alone, but allows it to pass over if a solution of potash be 
used. Its odour, he continues, is extremely penetrating, pun- 
gent, and disagreeable, resembling that of mice. This alkaloid 
is easily decomposed, and it appears probable, says the author 
of the article in question, that coneine exists only in the fresh 
plant, as he has never been able to detect it when in a dried 
state. The coneine contained in the extract made from the 
fresh plant, is soon decomposed. The seeds, however, retain 
it for a long time, as the author detected it in some that were 
sixteen years old. 
It is difficult to conceive how this principle which is retained 
so strongly by an acid, as to require a high temperature and 
a powerful base to extract it, can disappear by the mere pro- 
cess of drying. There must be some other cause than mere 
temperature to occasion this. I thought at one time that hu- 
midity might perhaps aid in this decomposition. 
To investigate this phenomenon, I began by endeavouring 
to obtain the coneine of M. Geiger. After having subjected 
the fresh plant to a prolonged distillation with water, to de- 
prive it of its essential oil, I placed the plant and the liquid re- 
maining in the still, in an earthen retort, and having added 
some caustic potash, adapted a worm to the retort and distilled. 
The liquid that was obtained reddened turmeric paper, and 
restored the blue colour to litmus reddened by an acid. The 
colour of these tests was also changed when they were held 
over the vials containing the fluid. These characters evi- 
dently were characteristics of alkalinity and volatility. The 
smell resembled that of mice. These properties being noted, 
I supersaturated the liquid with acetic acid, and continued 
the distillation, and then evaporated the whole by a very 
gentle heat. I obtained a dark brown extract of a very dis- 
agreeable odour. A portion of this extract was placed in 
water, in ether, and in ley, and left to macerate for several 
days, then introduced into a retort and subjected to distilla- 
tion. The product which was collected in a receiver, kept 
cold by a freezing mixture, was ether containing a volatile, 
alkaline principle, having a strong smell of cantharides. This 
