CHAP. I.
Of the General Properties of Mercury.
Of the General Properties of Mercury.
Of the General Properties of Mercury.
Mercuryis a production of the mineral kingdom. In its natural state, it is of an opaque metallic substance, of very considerable specific gravity. To the eye, it appears like melted lead, or silver; from which it has derived the name ofquicksilver. In this condition, when freed from every admixture, it has neither any perceptible smell nor taste; and, as its application to the most sensible parts of the body occasions no irritation, we may conclude, that it is void of all acrimony.
By very intense cold, artificially excited, mercury may be brought to a solidform; but, in the greatest natural cold hitherto known, it remains always in a fluid state. By heat it is rendered very volatile, exhaling totally in fumes; these fumes, upon being exposed to cold, condense again into running mercury.
Mercury, like most other metallic substances, is found in the earth, either in a pure state, or in that of an ore. The first has been calledvirgin-mercury, and is in general found by the miners in drops or small grains; sometimes indeed it is observed in larger quantities, and forms the appearance of small streams. In the state of ore, it is most frequently combined either with sulphur, or with earthy matters; from which it is readily extracted by distillation. It is found in both these states in different places of Europe, particularly in Spain and in Hungary; butBritain is principally supplied with it from the East-Indies.
Mercury was not unknown to the antients. In the early ages of medicine, indeed, it seems to have been esteemed a virulent poison; but it has now, for some centuries past, been much, and successfully, employed for the purposes of medicine, as well as of other arts.
The Arabians were the first who employed it in the cure of diseases; but they seem to have used it externally only, and applied it for discussing tumors, cleansing ulcers, and curing cutaneous eruptions. Soon after the introduction of the venereal disease into Europe, mercury was found to be the most expeditious and most effectual, if not the only certain, remedy. The advantages which are to bederived from its employment in this disease, both when applied externally, and taken internally, have now been confirmed for a length of time too considerable for allowing the least foundation either to doubt its efficacy, when properly used, or to dread its deleterious effects, when judiciously managed.
The effects of mercury on the human system in a sound state are very various. When mercury, in its crude state, is introduced by the mouth into the alimentary canal, it passes off by stool, without producing any effect. It has indeed been alledged, that in this state, in some morbid affections, it may be useful in removing obstructions by its weight. But it is to be remembered, that, in a great part of its passage through the intestines, it rises in opposition to gravity, and thatit is very apt to divide in such a manner as to make its way through very small openings. This effect, then, is perhaps in general, if not always, to be disregarded.
When mercury is prepared in such a manner as to be readily soluble in the fluids of the human body, the effects it produces are much diversified. Its action is often immediately exerted upon the stomach; in which case vomiting is produced. This effect is observed from the use of many mercurial preparations. The brown and green precipitates and calcined mercury act as rough and strong emetics; but the preparation principally used, where it is intended to act as an emetic, is the yellow precipitate, or Turpeth mineral.
Many of those mercurials, which havenot such an influence upon the stomach as to produce vomiting, upon entering the intestinal tube, act as purgatives. This effect of mercurials is, among other preparations, particularly remarkable on the use of the Coralline mercury, Prince’s powder, or calomel.
Mercurials, which fail in producing either purgative or emetic effects, frequently act as diaphoretics. Diaphoresis, or even a profuse sweat, is often the consequence of many of the mercurials already mentioned. But when this effect is wanted, by means of mercurials, it is most commonly obtained by the use of a solution of corrosive sublimate.
Mercury entering the circulating system exerts particular effects on different excretories; but in a more especialmanner on those of the saliva. Salivation is an effect which may be obtained from the proper administration of almost every mercurial preparation; but for this purpose either the mercurial pills, or friction with mercurial ointment, are most frequently employed.
Mercury may enter the system, exist in considerable quantity there, and be carried off by the different excretories, without producing any remarkable evacuation, or other apparent change, on the sound state of the body. That it is actually present in the system in such cases, is demonstrated by a general tendency to an increase in all the secretions. Mercury in this way, although it produces no visible effect on a healthy person, often procures the removal of a diseased state.Its action, therefore, in such circumstances, is termedalterative; an effect which may be obtained from most of the mild mercurials, especially when used in small doses.
From these various modes of operating, it may readily be concluded, that mercury must be a powerful remedy in the cure of many diseases. The undoubted effects which it produces on the human system, when labouring under the venereal distemper, it would be both difficult and unnecessary fully to enumerate. It heals ulcers, removes swellings, alleviates pains, and cures eruptions. In short, the almost infinite variety of symptoms under which this disease makes its appearance may, by a proper application of mercury, be effectually eradicated from the constitution.
From these effects, it is not surprising, that, in this distemper, mercury is the almost universal remedy. But, while it cannot be denied that peculiar advantages may be reaped from the employment of mercury in the venereal disease, it must at the same time be acknowledged, that, from the injudicious use of this medicine, very great evils have been produced. Whatever, therefore, relates to its proper administration, must be esteemed of importance. But to determine this, it is in the first place requisite to ascertain the principles upon which it operates. In treating of the present subject, then, an examination of the most probable opinions, with regard to the mode of its operation in the venereal disease, first claim our attention.