The trials of the gummy mercurial that have come to my knowledge, afford little foundation to expect from it any advantages above the common mercurial preparations, I have known it given, without much benefit, in cases which were afterwards cured in a short time by solution of sublimate. I have been informed, that in some of our hospitals even smaller doses than thole directed by the author have on the third day brought on a ptyalism. Dr. Baldinger, in his remarks on the last Edinburgh pharmacopoeia, recommends this solution as an efficacious anthelmintic, especially against the lumbrici.

Mercury, thus simply divided by these or other like matters, seems to operate more mildly, not only in the first passages, but after it has been received into the blood, than when combined with mineral acids, or reduced by fire into the form of a calx. At the same time, however, it is more uncertain, or more liable to fail of taking full effect; on account, perhaps, of the substances, by which its particles are disuni-ted, being soon subdued and separated by the digestive powers, so as to leave part of the mercury to run together again and pass off inactive through the intestines. How easily the union is dissoluble, may be judged from hence, that when mercury is perfectly mixed with turpentine, if the mixture be beaten up with extracts and powders into a mass for pills, a considerable part of the quicksilver, by this mechanic agitation, is often separated and squeezed out in globules.

Mercury, triturated with equal its weight of sulphur, forms therewith a greyish black powder, which grows darker coloured in keeping, or on continuing the triture, and is commonly distinguished by the name of aethiops. This compound is one of the mildest of the mercurial preparations; the mercury being far less active in mixture with sulphur, than with any other known species of matter.

The union of the quicksilver with the sulphur, effected by triture, at least by such a degree of triture as the shops are accustomed to bestow upon them, is not intimate any more than that with the substances above mentioned. If the aethiops be rubbed on gold, a part of the mercury adheres to the gold so as to make it white: on mixture with syrups or other like matters into the consistence of an electary or mass for pills, a part of the mercury is generally spued out. The longer the quicksilver and sulphur are ground together, the less they will be dis-posed to separate; a circumstance which does not appear to obtain in the mixtures of mercury with resinous or earthy bodies.

Hydrargyrus cum sulphure Ph. Lond.

aethiops mi-neralis Ph. Ed.

A more intimate coalition of mercury and sulphur may be speedily effected, by melting the sulphur over a gentle fire, and gradually stirring into it the quicksilver, with care to cover the vessel if an ebullition or swelling up of the matter shews it ready to catch flame; an accident which sometimes happens when the quantities are large. This compound gives no whiteness to gold, and suffers no reparation of its parts on being made into electaries or other forms. Even the acid solvents of mercury are incapable of extracting it when thus combined with sulphur; and the alkaline solvents of sulphur extract only, by long boiling or digestion, so much of that concrete as is more than sufficient to satiate the mercury.

If mixtures of quicksilver and sulphur, thus intimately united by fire, in due proportions, as twenty-four or twenty-five parts of the former to seven of the latter, be powdered and let to sublime; the two ingredients rife together without separation, (except that a part of the sulphur, and generally a very considerable one, burns away in the process,) and concrete, in the upper part of the subliming jar, into a red mass called cinnabar or vermilion. This preparation, though containing much more mercury than the aethiops, does not appear to be more active; and is by many looked upon rather as a medicine of the antispasmodic kind, than as possesiing the proper virtues of mercurials.

aethiops cum igne, vulgo.

Hydrarg. sulphuratus ruber Ph. Lond.

Cinnabaris facitia Ph.

Ed.

Indeed the real virtues, either of cinnabar or of aethiops, cannot perhaps be precisely assigned.

When mercury is intimately combined with a certain quantity of sulphur, it seems to operate, though given in considerable doses, as a scruple or half a dram of the compound, only in an insensible manner; and in many cases, to pass off inactive through the intestinal tube (a). It may be presumed, that an increase of the sul-phur, beyond the quantity sufficient for this perfect satiation of the mercury, will not vary its action; but that a diminution of the sulphur will leave the mercury, or a part of it, in a state of more activity ; analogously to what has been before observed to happen in regard to the an-timonial regulus. It may be presumed also, that in perfect cinnabar the mercury is completely saturated, and that in perfect aethiops, it is both saturated, and blended with some redundant sulphur: but that in some cinnabars, it is not saturated from a deficiency in the quantity of sulphur; and that in some sorts of aethiops it is not saturated, from an imperfection in the mixture. There are examples both of aethiops and cinnabar, one of which, in regard to the latter, has fallen within my own knowledge, having unexpectedly produced salivations. It should seem therefore, that the aethiops made by fire is the most to be depended on, or the most certain and equal in its power, whatever this power may be, of any of the sulphurated mercurials.

When aethiops or cinnabar are thrown on a red-hot iron, their fumes are of great activity. The fumes of cinnabar are sometimes directed, not only to be received on the lower parts; but likewise to be taken into the mouth, against venereal ulcerations in the nose, mouth, and throat. Of all the ways of applying mercury, this last requires the greatest caution.