Evacuants may perhaps be alledged to operate in the cure of _lues venerea_ in another manner. It may be supposed, that they remove the distemper from a change which they produce in the quality of the circulating mass. But, from the smallest consideration, it will appear, that this supposition is equally unsatisfactory as the former. If, from evacuation, a diminution takes place equally from every part of the mass of circulating fluids, no change of quality will ensue. If, however, this proportion is not properly observed, a change of quality will indeed take place. But that change will consist merely in the diminution of particular parts in a compound mass, and can never be supposed to remove a contagious matter of any kind, even supposing it to be lodged in the particular part of that mass thus diminished. Much less will it remove an infectious matter uniformly diffused through the whole parts of the compound mass, or existing as a morbid matter in particular parts of the body only. From the nature of evacuation, then, whether it be supposed to operate by a diminution of the quantity of circulating fluids, or by any change it can produce in point of quality, it may readily be concluded, that it is by no means fitted for the cure of _lues venerea_. Another and more conclusive objection against the supposition that mercury cures _lues venerea_ by evacuation, is, that this disease is by no means cured by evacuation taking place in an equal, or even in a greater degree, from other causes. This, however, should of necessity be the case, were the former supposition well founded. Effectually to overturn this theory, then, it will be necessary only to establish the truth of this assertion. It cannot perhaps be alledged, that any fair trial has ever been made of evacuation, instituted solely with a view to cure the venereal disease, and that in such cases it has been found to fail. But, without any such trial, there are sufficient arguments to shew, that for this purpose it really is ineffectual. _Lues venerea_ would never, upon its first introduction, have been considered as so unconquerable a disease, could it have been cured by evacuation. Various modes of evacuation were then in common use in medicine, and considered as the most effectual means of cure in many diseases. The venereal distemper, till the introduction of mercury, resisted the power of almost all the medicines employed against it; and, in some parts, it was at that time reckoned so incurable, that the police of the country obliged the unhappy sufferers who laboured under it to separate themselves from all intercourse with the rest of mankind. While this was the condition of the distemper, is it to be imagined that every method of cure was not tried? May we not, then, conclude, that, upon the first introduction of this disease, evacuation, by every known means, and carried to the greatest height, was had recourse to, but without effect?