This topic involves a consideration of the essential nature of the structural and functional changes resulting from pyogenic infection of the middle ear. The limited time allotted for such purpose permits but brief discussion of such alterations and it will be my pleasure to present the varying stages of the disease as nearly as possible in the order in which they occur, considering their progress as concisely as possible.
As a foundation for the correct understanding of conditions underlying the disease, it may not be amiss to refer casually to the anatomic and histologic character of the structures to be dealt with and the provisions Nature has made to prevent or to resist purulent invasion of this organ. In the first place, it must be clearly understood that the middle ear does not mean simply the tympanic cavity. From the clinical point of view, it would probably be proper to