If, from this test, it appear, that the want of obvious action after the use of mercury proceeds from its not having entered the system, a very different treatment is necessary from what was proposed in the former case. Here it is requisite, without loss of time, to have recourse either to a different preparation of mercury from what was formerly used, or to a different method of introducing the medicine. The circumstances already mentioned as claiming attention, regard peculiarities of constitution where no other disease except _lues venerea_ can properly be said to exist. But it often happens, that the venereal disease exists in patients who are, at the same time, affected with other complaints. This affords a very extensive field for particulars to be attended to in the employment of mercury. To treat of the variety of diseases which may, in any degree, be affected by it, would be an almost endless task. In some, the mercury will be of service, as tending to a cure; many others, on the contrary, are by its use rendered evidently worse. Its influence in aggravating complaints has been said to hold, among a variety of other diseases, in cases of epilepsy, gout, and rheumatism. But on this subject attention is chiefly requisite to scurvy and hæmoptoe. In scurvy, mercury very generally occasions a quicker progress of all the complaints. Hence, when, in such circumstances, it easily can be avoided, it is a medicine never to be employed. Cases, however, will occur, in which, although scurvy actually does exist, the use of mercury will be adviseable. In such cases, if the mercury is used slowly and cautiously, a cure of the venereal symptoms may be obtained, without rendering the scorbutic complaints much worse; but, if the mercury be suddenly thrown in, disagreeable symptoms will often arise. Of these, the principal are fœtid gangrenous ulcers, affecting the inside of the cheeks, the tongue, the palate, or the gums. It may farther be observed, that, although these are in general the consequences of the imprudent use of mercury; yet they will sometimes arise where it has been used even with the greatest caution. When they do happen, let their cause be what it will, there is, in every case, so much danger as to make it necessary to discontinue the use of mercury. Recourse is then first to be had to the employment of such means as are best calculated for the removal of scurvy. If this can once be effected, the removal of the venereal complaints may be attempted, either by the employment of other means of cure, or even by resuming the use of mercury.