Cinnabaris. Ed. - Deutosulphuret of Mercury. - Bisulphuret of Mercury. - Persulphuret of Mercury.

Though formerly recognized by the London and Edinburgh Colleges, this has been abandoned in the British Pharmacopoeia, and is now acknowledged only by our own. it is made by heating mercury and sulphur together, and then subliming. The two unite in the proportion of two equivalents of the sulphur to one of the mercury.

Artificial cinnabar is in the form of heavy, deep silvery-red, glistening, crystalline, and striated lumps, which yield, when pulverized, a beautiful brilliant-red powder called vermilion. it is inodorous, tasteless, insoluble in water and alcohol, and not acted on, like the other mercurials, by the alkaline chlorides. When heated in close vessels, it volatilizes unchanged, but in the air is decomposed, the sulphur undergoing combustion, and the mercury rising in vapour.

Medical Effects and Uses

This sulphuret is thought to be entirely-inert in its unaltered state. The only use made of it is for the purpose of mercurial fumigation. Being converted by heat, with access of air, into sulphurous acid and mercurial vapour, it becomes efficient in this method of application, and has sometimes been used in venereal ulcers of the throat, and in other cases requiring a very speedy salivation. in order to this effect, the vapours must be inhaled; and the obvious objection occurs, that, as the sulphurous acid must be inhaled at the same time, very unpleasant and even hazardous irritation of the air-passages might be endangered. When the object, therefore, is to introduce mercurial vapours into the lungs, the black oxide or calomel would be decidedly preferable.

But the vapours of cinnabar have also been applied to the external surface, and in this way may sometimes prove serviceable. it is especially in syphilitic eruptions that they have been thus employed; but they might also be used in any other obstinate eruption, demanding a powerfully alterative and stimulant impression. in such cases, the attendant sulphurous acid may be useful. From ten grains to a drachm or two of the cinnabar may be used, according to the extent of surface which it may be desired to affect. it may be simply placed on a plate of heated iron, which, when the application is to be general, must be introduced within a vapour bath, especial care being taken that the head of the patient shall project, and that the aperture around his neck be well closed. When the application is to be limited to a single limb, it may be introduced into a box made for the purpose, with an opening to admit the limb.. it may be sufficient, sometimes, to direct the vapours upon a particular spot, by means of an instrument resembling a funnel.