3. =Chronic Swelling.=--This is something more than the swelling alluded to under _Acute Swelling_. Chronic swelling implies either a continuous passive hyperemia, or, what is more common, a positive increase in tissue elements as the result of an oversupply of nutrition brought by the blood, which itself was furnished to the part in a degree far in excess of its needs. The result is a more rapid reproduction of cell elements, with result in the shape of tissue thickenings or tissue enlargements, known as _hypertrophy_, or, more properly speaking, _hyperplasia_, of a part, and to the laity as “overgrowth.” This chronic swelling or chronic enlargement is in some degree also connected with the phenomena of escape of white corpuscles from the bloodvessels and mitotic division of certain tissue cells, which have up to this time been usually regarded as a feature of the true inflammatory process. 4. =Gangrene.=--This may be the result of hyperemia--for the most part the passive forms--though most instances of gangrene due to intrinsic causes are inseparable from the presence of infectious microörganisms. The gangrene which is spoken of here includes that due to the pressure of tumors, tight dressings, or any natural or intrinsic agency, and that due to pressure from without when not so pronounced as to produce immediate and total loss of circulation in a part. It includes the formation of many bed-sores and so-called _pressure-sores_, which may be due to an enfeebled heart, to an obstructed pulmonary circulation, or to external pressure in conjunction with cardiac debility. While insisting, then, that gangrene should be recognized as a possible result of hyperemia, it may be added that it is in effect a tissue death, and that dead tissue is always and everywhere practically the same thing, no matter by what causes brought about. Consequently, the subject of gangrene will be considered under a separate heading. 5. =Nutritional Changes= will be considered later. _The consequence of persistent hyperemia is transudation_--i. e., _escape of blood plasm from the vessels into body cavities and tissue interspaces_. This leads to consideration under a distinct heading of-- TRANSUDATES AND EXUDATES. Exudation may occur in vascular and non-vascular, in firm and soft tissues, in, under, and upon membranes. With respect to location, exudates are described as _free_, when found upon free surfaces or within natural cavities; _interstitial_, when found between the tissues or parts of tissues; and _parenchymatous_, when they are situated within the tissues themselves, particularly in epithelial and glandular cells of any kind. Exudates are _serous_, _mucous_, _fibrinous_, or _mixed_, the mixed forms including the so-called _seropurulent_, the _mucopurulent_, the _croupous_, and the _diphtheritic_. When any exudate contains red globules in sufficient quantity to stain it, it is called _hemorrhagic_.