Syphilis appears to account for a very considerable proportion of the more serious cases of heart disease which we meet with in older subjects--excluding of course chronic valvular disease originating remotely in endocarditis. But I ought to repeat here what I have already mentioned, that syphilis as a cause of cardio-vascular lesions is very often associated with other morbific influences, particularly strain and alcohol. Of its position as the principal cause of grave disease of the valves as distinguished from the walls of the heart, originating in middle life, there can be no question. No fewer than nine out of 28 cases, of which I have private notes, were the subjects of double aortic disease; practically all the others had a loud ringing second sound over the aorta, significant of degeneration; pain of anginal type in half the cases was the prominent complaint; and two-thirds of the subjects had sclerosis of the radial artery. When we consider that syphilis does also affect the myocardium primarily; that fibroid disease, chronic aneurysm and fatty degeneration of the heart are all traceable to specific disease of the coronaries in many instances; and, finally, that many of the subjects of syphilitic cardio-vascular disease have perished before 40, the magnitude of this cause can be fully realised. I believe that the profession in general have not yet woke up, if I may say so, to the gravity of this subject. How seldom we inquire for a history of specific disease in patients coming to us with cardiac disease in middle life! To no one, as far as my reading goes, are we so much indebted for the truth on this subject as to my friend and colleague Dr. Mott. Thirteen years ago he published a paper on 21 cases of sudden death from cardio-vascular disease, and in nine of these there was a history of either actual or probable syphilis. What was of greater interest, however, at that early date, he drew attention to the association of syphilitic cardio-vascular lesions with Bright's disease in the broad acceptation of the term. Dr. Mott's work in the interval on syphilitic lesions of the arterial system of the brain has been so brilliant, and is so generally known, that it requires nothing more than this appreciative mention by me, and it saves me the trouble of an excursion into the subjects of cerebral hæmorrhage and thrombosis in connection with these lectures. NERVOUS STRAIN.