SULPHURETUM HYDRARGYRI RUBRUM. D. Olim, _Hydrargyrus Sulphuretus ruber_.
_P. L._ 1817—_Cinnabaris[532] factitia_, 1745.
QUALITIES. _Form_, a red crystalline cake, inodorous, insipid, and
insoluble in water, alcohol, acids, and alkalies, although these bodies
decompose it when melted with it; it is also decomposed by
nitro-muriatic acid, which unites with the metal, and disengages the
sulphur. CHEMICAL COMPOSITION. It is a _bi-sulphuret of Mercury_, i. e.
it consists of two proportionals of sulphur and one of mercury.
USES.[533] It is now only used for the purpose of mercurial fumigation,
which is done by inhaling the fumes, produced by throwing ʒss of it on
red hot iron; the effect which is generally produced is violent
salivation; this however does not depend upon the action of the
substance as a _sulphuret_, but upon its decomposition, and the
volatilization of the metallic mercury with a portion of sulphate and
sulphureous vapour. Mr. Pearson observes that it is useful in those
cases of venereal ulcers in the mouth, throat, and nose, where it is an
object to put a _sudden_ stop to the progress of the disease, but that
mercury must at the same time be introduced into the constitution, by
inunction, just as much as if no fumigations had been made use of.
Ulcers and excrescencies about the pudendum and anus in women are
particularly benefitted by it; and in these cases it is conveniently
applied by placing a red hot heater at the bottom of a night-stool pan,
and after sprinkling on it a few grains of the sulphuret, placing the
patient upon the stool. ADULTERATIONS. _Red Lead_[534] may be discovered
by digesting it in acetic acid, and by adding sulphuret of ammonia,
which will produce a black precipitate; or by burning a small portion of
the suspected sample on a piece of bread in the candle, when metallic
globules will announce its presence; for the oxide of mercury, although
revived by this process, will at the same time be volatilized. The
bread, by combustion, affords the carbon by which the metallic reduction
is effected. _Dragon’s Blood_, by its giving a colour to alcohol when
digested with it; _Chalk_, by its effervescence, on the addition of an
acid. It is known in the arts under the name of _Vermillion_; and by the
following simple expedient its presence may, in very minute quantities,
be easily recognised; boil a portion with sulphuric acid in a platina
spoon, and lay the sulphate thus produced, in a drop of muriatic acid,
on a piece of gold, and bring a piece of metallic tin in contact with
both, when the white mercurial stain will be produced.
HYDRARGYRI SULPHURETUM NIGRUM. L.E. Hydrargyrus cum Sulphure. P.L. 1787.
Olim, _Ethiop’s Mineral_.
QUALITIES. _Form_, a very black, impalpable, insipid, and inodorous
powder. CHEMICAL COMPOSITION. It is a _Sulphuret of Mercury_, i. e. it
consists of one proportional of sulphur, and one proportional of
mercury; when heated in contact with the air it is converted into a
_bi-sulphuret_. SOLUBILITY. It is entirely soluble in a solution of pure
potass, from which the acids precipitate it unchanged; it is insoluble
in nitric acid. MED. USES. It is supposed to be alterative, and has been
given for such a purpose, in doses from gr. v. to ʒss, but its medicinal
virtues are very questionable. ADULTERATIONS. It is frequently
imperfect, globules of mercury being still discoverable in it by a
magnifying glass, or by its communicating a whiteness to a portion of
gold upon which it is rubbed; _ivory black_ may be discovered by the
residue, after throwing a suspected sample on a red hot iron; it is also
sometimes mixed with equal parts of crude antimony.