The rôle of ophthalmology in preventive medicine includes, it seems to me, at least three phases which may be profitably studied by the general profession: 1. Prevention of blindness from infectious diseases and accidents. 2. Prevention of eye deterioration by violation of ocular hygiene. 3. Prevention of remote lesions through recognition of early ocular symptoms of systemic disease. It is my purpose to speak briefly of each of these, bearing in mind the fact that this section has to do rather with the practical results of scientific study than with the details of the study itself.
Among infectious eye troubles, the most destructive, by long odds, is ophthalmia neonatorum. The number of its victims is little short of a professional disgrace. Its cause is definitely known. While due exceptionally to infection other than gonococcic, and while differential diagnosis is important, the fact remains that clinical experience shows the