POISONING BY VEGETABLES. 
295 
when in contact with animal matters at a temperature of 
211° F., or a few degrees above it ; 2d, that ammonia pre- 
cipitates the vegetable alkalies from their acid solutions 
when present, to the extent of a thousandth part and less. 
The two processes have this in common, that at first 
whatever the matters for analysis may be, they must be 
dried in a sand-bath at a temperature not exceeding 239° F- 
They are then broken up, and afterwards powdered in a ma- 
chine described in the first volume of the author's "Traite 
des Poisons," p. 414. 
The matter thus prepared is treated, according to the 
more or less dry or coagulable'state of the products, either 
with water acidified with 0.025 — 0.05 acetic acid, or with 
absolute alcohol, to which, according to the nature of the 
proximate principle to be sought for, a small quantity of 
powdered oxalic or tartaric acid is added. This addition 
of acid, which can, or rather ought to be made either before 
or after the treatment with alcohol, serves to transform the 
vegetable alkaline base into an extremely soluble salt or 
supersalt ; because this salt has to be subsequently taken up 
by cold water, so that the base may be precipitated by am- 
monia. 
In the analysis of the urine, the treatment must be special; 
but it is easily described. The liquid should be evaporated 
to the consistence of an extract, this completely dried by 
adding powdered alumina, and the solid, when perfectly 
pulverized, treated with cold water acidified with 0.02- 
0.05 acetic acid. The solution is precipitated by ammonia, 
the precipitate washed and collected. 
In using these processes, it is no longer the extracts of 
animal matters which are subjected to the chemical reac- 
tions adopted for detecting the vegetable bases sought for; 
these bases are obtained in a pure state, or in the form of 
crystals. The author uses a small peculiar filter, described 
by M. Danger, by which the smallest quantity of any pre- 
