This is a discussion of the subject of wounds of the chest, especially those in which hemothorax develops, with perhaps a later empyema. The causation—usually a bullet, shrapnel or shell splinter—is considered, together with the symptomatology and the results by various methods of treatment. The author had his schooling with Forlanini, whose work on the treatment of pulmonary tuberculosis, pulmonary hemorrhage, pleural effusions, etc., by means of artificial pneumothorax, is well known. It is not to be wondered at, therefore, that Morelli has applied the same principle to the treatment of this not infrequent accident of war. He has developed a technic that is accurately described in these pages and which, carefully carried out, has given surprisingly fine results, as shown by the case histories and the roentgenograms. The dangers of open pneumothorax as compared to closed are emphasized, a point that has been brought out by Duval and others