OF POISONING WITH ANTIMONY.
The fourth genus of the metallic irritants includes the preparations of
antimony. Poisoning with antimonial preparations is not common. They are
employed extensively in medicine, however, and consequently accidents
have sometimes occurred with them. One of them is also often foolishly
used, in the way of amusement, to cause sickness and purging, and
likewise to detect servants who are suspected of making free with their
mistress’s tea-box or whisky-bottle; and in both of these ways alarming
effects have sometimes been produced. In 1837 a woman was tried in
England for attempting to poison a child with tartar-emetic; but the
poison appeared to have been given through ignorance.[1129] In large
doses some of the antimonial compounds may cause death; and one of them,
the chloride of antimony, now very little used in this country, is a
violent corrosive.
SECTION I.—_Of the Chemical History and Tests for the preparations of
Antimony._
Metallic antimony has a bluish-white colour, not liable to tarnish. Its
specific gravity is 6·7. It is easily fused, but is not very volatile.
In certain circumstances, however, it easily undergoes a spurious
sublimation, by being carried along with gases disengaged while it is in
the act of being reduced.
A great number of preparations of antimony were at one time to be found
in the shop of the apothecary; but they are now reduced to a few. Those
which require notice here are the oxide, chloride, and tartar-emetic.
The _oxide_ [sesquioxide] is a white heavy powder, which is best known
by its solubility in tartaric acid, and the effects of the tests for
tartar-emetic on the solution.
The _chloride_ [sesquichloride], as usually seen, is a yellow or reddish
liquid, but when pure is colourless. It is highly corrosive. It is
readily known by the effect of water in decomposing it,—an insoluble
white subchloride being thrown down, and hydrochloric acid remaining in
solution. The latter is detected by nitrate of silver; and the
precipitate is known by being soluble in a solution of tartaric acid,
and then presenting the reactions of tartar-emetic.
_Tartar-Emetic._
In its solid state tartar-emetic forms regular tetraedral or more
generally octaedral crystals, which are colourless when pure,
efflorescent, and of a slightly metallic taste. As commonly seen in the
shops it is in the form of a white, or pale yellowish-white powder.
When heated it decrepitates and then chars; and if the heat be increased
the oxide of antimony is reduced by the carbonaceous matter, and little
globules appear, like those of quicksilver in point of colour. The best
way of reducing tartar-emetic is to char it in a porcelain vessel or
watch-glass, and then to increase the heat till the charred mass takes
fire. Or the charred mass may be introduced into a tube and heated
strongly with the blowpipe, after which globules of antimony will be
found lining the bottom of the glass where the material has been. None
of it is ever sublimed. It is not easy to procure distinct globules by
heating tartar-emetic at once in a small tube.
According to Dr. Duncan, tartar-emetic is soluble in three parts of
boiling and fifteen of temperate water. The solution presents the
following characters with reagents.