They are Blood, Choler, Phlegm, and Melancholy, every one whereof produceth its particular Tumour: Thus the Blood produces the _Phlegmon_, Choler the _Erysipelas_, Phlegm the _Oedema_, and Melancholy the _Scirrhus._ The Mixture of these is in like manner the Cause of the _Erysipelatous Phlegmon_, the _Oedomatous Phlegmon_ or _Phlegmonous Erysipelas_, and the _Phlegmonous Oedema_, according to the quality of the Humours which are predominant, from whence the several Tumours take their Names. _What are the _Encysted_ Tumours?_ They are those the Matter whereof is contain'd in certain _Cystes_, or Membranous Bags; as the _Meliceris_, and the _Struma_ or Kings-Evil. _What are Critical Tumours?_ They are those that appear all at once in acute Diseases, and terminate them with good or bad Success. _What are Malignant Tumours?_ They are those that are always accompany'd with extraordinary and dreadful Symptoms, and whose Consequences are also very dangerous; as the Carbuncle in the Plague. {100} _What are Impostumes or Abcesses, Breakings out and Pustules?_ Indeed, it may be affirm'd, that all these kinds of Tumours scarce differ one from another, except in their size or bigness; nevertheless, to speak properly, by the Names of Impostumes or Abcesses are understood gross Tumours that are suppurable, or may be dissolv'd, and by those of Breakings out and Pustules, only simple Pusteal Wheals, or small Tumours, that appear in great Numbers, and which frequently do not continue to Suppuration; some of them consisting of very few Humours, and others altogether of dry Matter. _What difference is there between a Tumour and an Impostume or Abcess?_ They differ in this particular, that all Tumours are not Impostumes nor Abcesses; but there is no Impostume nor Abcess that is not a Tumour: As for Example, Wens and _Ganglions_ are Tumours, yet are not Abcesses nor Impostumes; whereas these last are always Tumours in regard that they cause Bunches and Elevations. * * * * * CHAP. II. _Of the general Method to be observ'd in the curing of Tumours_. _What ought a Surgeon chiefly to observe in Tumours, before he undertake their Cure?_ He ought to know three things, _viz._ 1. The Nature or Quality of the Tumour. 2. The {101} time of its formation and 3. Its situation: The Quality of the Tumour is to be known, because the Natural one is otherwise handl'd than that which is Encysted, Critical or Malignant. As for the time of its Formation, it is four-fold, _viz._ the Beginning, Increase, State, and Declination, wherein altogether different Remedies are to be apply'd. The Situation of the Tumour must be also observ'd, because the dressing and opening of it ought to be as exact as is possible, to avoid the meeting with an Artery or neighbouring Tendon. _How many ways are all the Tumours that are curable, terminated?_ They are terminated after two manners, _viz._ either by dissolving 'em, or by Suppuration.