These affections are probably as old as the creation of man, as the conditions producing them must have obtained ever since man first became sick. Hence, I scarcely think that much that is new can be said on the subject; it is possible, however, that I may say something that will cause some one to search deeper than ever before, and thus enable him to save a life that otherwise would have been sacrificed. But the best motive I have in writing is to provoke some discussion that may throw more light on diagnosis or treatment that may prove of benefit to the practitioner and to the one mostly concerned, the patient. These pleural effusions, though fairly easily diagnosed by the expert, are too frequently overlooked by the rank and file of the profession, and, secondly, often when diagnosed, are not treated with sufficient vigor, but allowed to drift on