1. _The poison is in a solid form._ Dissolve a portion of the suspected
salt in about fifteen times its weight of boiling distilled water; if it
be emetic tartar, the following reagents will identify it, viz.
(_a_) _The hydrosulphurets_ will occasion a reddish-yellow precipitate,
which is a combination of _oxygen_ and _antimony_, proceeding from the
emetic tartar; and of _hydrogen_ and _sulphur_, from the reagent
employed. If it be dried on a filter, and mixed with charcoal and the
potass of commerce, it gives, by the action of heat, a cake of metallic
antimony.
(_b_) _Tincture of galls._ This is regarded as the most sensible test of
this salt, affording a precipitate of a curdled, dirty white colour,
inclining to yellow.
(_c_) _Lime water._ This reagent produces a white precipitate, which is
extremely thick, and is easily redissolved by pure nitric acid. In this
case the lime forms an insoluble tartrate, and the tartrate of antimony,
thus rendered insoluble, subsides along with it.
(_d_) _Concentrated sulphuric acid_ gives a white precipitate, which
consists of the oxide of antimony retaining a small portion of the acid.
It redissolves in an excess of the precipitant.
(_e_) _Vegetable extractive_, occasions in the solution of this salt, a
reddish-yellow precipitate, which has been found to consist of _oxide of
antimony_, and a portion of vegetable matter.