_Fælix Wurtz_, who was a very judicious Surgeon, informs us, That it sometimes happens, that in a little time after a Patient has been cured of a Wound of the Head, he feels violent Pains there, which indicates that Matter is collected in the Part. He adds, That many die of it, by reason the Cause is not understood by some Surgeons. This Remark proves, that the Wounds were not kept open long enough, or else that the Surgeon acted imprudently in not making use of proper Means to divert the Tendency of the Humours to that Part; not but it will abundantly more easily happen to those Parts that are depending, and where the Weight of the viscid Fluid will incline it to settle. I knew a lusty Fellow, about twenty five Years of Age, that had an Ulcer on the internal Ancle of his left Leg near twelve Years: It had been cured three or four times, but he always found himself very much indisposed after it, till it broke out again, and the Matter had a free Discharge: At length, upon his coming from Sea, it was healed again, upon which he was seized with a violent Pain in his Head, Loss of Appetite, which the next Day was succeeded by a violent Fever and Looseness. His Physician ordered, among other Things, a large Blister-Plaister, to be applyed to the Leg on which the Ulcer had been. The Patient recovered; but what was very observable, was, that the Sore the Blister-Plaister had made terminated in an ugly Ulcer, which would not heal, though various Applications were made use of. If Nature had been in this Case compelled, as it were, and forced to a Compliance in the healing of this Ulcer, it is probable the Matter would have been thrown upon another Part, and so occasioned a Disease there. By this we may see how cautious we ought to be not to proceed in a Method contrary to the Dictates of Nature; for if we do, we consequently disturb her regular Motions, upon which she oftentimes commences a new Work, which, if it does not tend to the Subversion of the whole Oeconomy, there ensues a Permutation of the Disease, by the Translation of the Matter from one Part to another. It would be impossible to recount all the obscure Motions Nature makes use of to accomplish such Ends: We will only mention some where the Disease has been perfectly changed from what it was before by such Methods. _Mear_ gives us an Instance of a Dropsie of the Breast, which succeeded an ill-cured Hydrocele. _Hildanus_ observes, that an inveterate Ulcer of the left Leg being unhappily healed up, the Patient died of a Pleurisy some Months after.