It is not necessary to refer at any length in this place to the inflammations which may supervene. Diffused inflammation of the lung after wounds is not so common as might perhaps be expected. In unfavorable cases, the pleural cavity is generally found to be the seat of extensive inflammatory action or unhealthy accumulations, especially where irritation has been kept up by the presence of foreign bodies or the patient’s constitution has become from any cause debilitated. =Treatment.=—The object of the surgeon’s care must be in the first place to arrest hemorrhage; afterward, to remove pieces or jagged projections of bone, or any other sources of local irritation; and to adopt means to prevent interference with the natural process of cure, which takes place by adhesion of the opposite pleural surfaces near the wound in the first instance, and subsequently by cicatrization of the wound itself, or, as shown in an interesting preparation in the museum of the Army Medical Department at Fort Pitt, by contraction into a narrow sinus lined with a distinct adventitious membrane into which the small bronchial tubes open. Although the shock may happen to be considerable, attempts to rally the patient, if any be made, should be conducted very cautiously; the prolongation of the depressed condition may be valuable in enabling the injured structures to assume the necessary state for preventing hemorrhage. Hemorrhage from vessels belonging to the costal parietes should be arrested by ligature, as in other parts, if the source from which it proceeds can be ascertained, and if the flow of blood be so free as not to be controlled by the ordinary styptics. Operative interference of this kind is chiefly called for on account of secondary, not primary, hemorrhage. Hemorrhage from the lung itself must be treated on the general principles adopted in all such cases; the application of cold to the chest, perfect quiet, the administration of opium, and, if the patient be sufficiently strong, bleeding from a large opening until syncope supervenes. When blood has accumulated in any large quantity, and the patient is much oppressed, the wound should be enlarged, if necessary, so as, with the assistance of proper position, to facilitate its escape. If the effused blood, from the situation of the wound, cannot be thus evacuated, and the patient be in danger of suffocation, then the performance of paracentesis, as directed for the relief of empyema, must be resorted to.