_Are not the_ Scirrhus _and the_ Esthiomenus _or Gangrene, two means that sometimes serve to terminate and cure Impostumes?_ Yes, but it is done imperfectly, in regard that a Tumour or Impostume cannot be said to be absolutely cur'd, as long as there remains any thing of the Original Malady, as it happens in the _Scirrhus_, where the Matter is harden'd by an imperfect dissolving of it, or when the Impostume degenerates into a greater and more dangerous Distemper, as it appears in the _Esthiomenus_ or Gangrene that succeeds it. _Which is the most effectual means of curing Impostumes, that of dissolving, or that of bringing them to Suppuration?_ That of dissolving 'em is without doubt the most successful, and that which ought to be us'd as much as is possible; nevertheless some Cases are to be excepted, wherein the Tumours {102} or Abcesses are Critical and Malignant; for then the way of Suppuration is not only preferable, but must also be procur'd by all sorts of means, even by opening; which may be done upon this occasion, without waiting for their perfect Maturity. _What are the Precautions whereto a Surgeon ought to have regard before he undertake the opening of Tumours?_ He must take care to avoid cutting the Fibres of the Muscles, and in great Abcesses, to cause all the corrupt Matter to be discharg'd at once, to prevent the Patient's falling into a Swoon. _Ought the opening of Tumours always to be made longitudinally, and according to the direct Course of the Fibres?_ No, it is sometimes necessary to open 'em with a Crucial Incision, when they are large, or when a _Cystis_ or Membranous Vehicle is to be extirpated. _How many sorts of Matter are there that issue forth in the Suppuration of Tumours?_ There are four sorts, _viz._ the _Pus_, _Ichor_, _Sanies_, and _Virus_. _What is_Pus_?_ It is a thick Matter, and white as Milk. _What is _Ichor_?_ It is a thick Matter like the _Pus_, but of divers Colours. _What is _Sanies_?_ It is a watery Matter that riseth up in Ulcers, almost after the same manner as the Sap in Trees. _What is _Virus_?_ {103} It is a kind of watry Matter, being whitish, yellowish, and greenish at the same time; which issueth out of Ulcers, very much stinking, and is endu'd with corrosive and malignant Qualities. _How many general Causes are there of Tumours?_ There are three, _viz._ the Primitive, the Antecedent, and the Conjunct: The Primitive is that which gives occasion to the Tumours; as for Example, a Fall or a Blow receiv'd. The Antecedent is that which supplies it with Matter, such is the Mass of Blood that thickens and maintains the _Phlegmon_. Lastly, the Conjunct Cause is the overflowing Blood or Matter, which immediately forms the Tumor. _What regard ought to be had to these three sorts of Causes in the Cure?_