Nor are these the only Cases in which good Service may be had from this Weighty Fluid; he that rightly considers the State of the Animal _Oeconomy_, the various Alterations it suffers from the Stagnation of its more Viscid Juices in the smallest Canals, and how much the Impulse and Force of the Circling Blood, by which Obstructions are to be removed, must be increased by its carrying along with it such Particles as the _Mercurial Globuli_, will perhaps see good Reason to allow, that the prudent and cautious Management of _Quicksilver_ may do that in some obstinate and dangerous Diseases, which we cannot promise our selves from any other of our known Medicines whatsoever.
But I am not to insist on this Head; and the learned _Author_ of the _New Theory of Fevers_ (120), has already most ingeniously explain’d the _Mechanism_ by which such Effects as these are produced in the humane Body. It suffices to my present purpose, to have proved that pure _Mercury_ is not Poisonous or Corrosive; and therefore not only have I seen Two Ounces of It given every Day for One and Twenty Days together, without any Inconvenience at all; but found once some quantity of It in the _Perinæum_ of a Subject I took from the Gallows for a Dissection (whose rotten Bones quickly discovered what Disease it was had required the Use of it, and that I suppose chiefly in External Application by Unction) without any Marks of Corrosion of the Part where it was lodged.
Tho’ withal we may upon this Occasion remark, that the extreme Gravity of this Mineral alone, however serviceable it may be in other Respects; yet when it happens in so great a Quantity to Obstruct the Capillary Ducts, as that the Force of the Circling Fluid is not sufficient to Wash it away, must necessarily induce Symptoms troublesome and bad enough, as _Spasms_, _Contractions_, _Palsies_, &c. which They do commonly Experience, who have either been too often dawbed with _Mercurial Ointments_, or for a long time imploy’d in rubbing the _Quicksilver_ upon _Looking-Glasses_; for the Internal Use of It will never produce any such Mischiefs.
As for _Sublimate_ then, most certain it is, that the _Saline_ Particles do impart to the _Mercury_ this Malignant Quality; or to speak more properly, That the _Salt_ receives from the _Mercurial Corpuscles_ such an Increase of its Gravity and _Momentum_, as renders its Cutting Corrosion more Effectual and Penetrating; for the manner after which this Matter is done, is plainly this.