1. =Resolution.=--The speedy subsidence of hyperemic phenomena is known as _resolution_--a term which has also been applied to the retrograde phenomena after a genuine inflammation. For present purposes it implies, first, the subsidence into inactivity of the exciting cause or its complete removal. This may include the passing of an emotion, the removal of an irritant, the loosening of a bandage, the resort to certain applications or to constringing or astringing measures by which the effect is counteracted. A particle of dust in the conjunctiva may within a few moments produce an active congestion of the conjunctival vessels, which, ordinarily scarcely visible, becomes prominent and easily noted. The removal of the offending substance permits a return to their original size in perhaps a half-hour. This is an example of the speedy subsidence of the hyperemia of dilatation after removal of the cause. Should the hyperemia not subside promptly, it is well to use cold applications, or in this instance an astringent collyrium, or some agent whose physiological effect it is to produce vascular contraction, as cocaine, adrenal extract, etc. 2. =Acute Swelling.=--When the effusion above referred to takes place into loose connective tissues the condition is spoken of technically as _edema_, while when it occurs into a previously existing cavity, such as that of a joint, it is known as an _effusion_. The amount of blood thus effused will be influenced by the anatomical and mechanical conditions existing about the part. It may be presumed, as a general rule, that when the extra vascular pressure equals the intravascular pressure little or no more fluid may escape. As a matter of fact, it is seldom that the former rises to the degree of the latter. Conversely, one method of treating such edemas and effusions is by some device which shall make the extravascular pressure exceed the intravascular, when the fluid is, as it were, forced back into the vessels, and is made to resume its proper place within the same. This is often done by taking advantage of elastic compression, as when a rubber bandage is applied about the part. In certain parts of the body it may be done by pressure brought about by some other device. Pressure may be used for two purposes: _A._ To so increase extravascular pressure as to limit the possible amount of an effusion, as when it is put on early after an injury; or, _B._ When it is used as a later resort for the purpose of reducing swelling which has already occurred.