I am on the point of passing from the subject of the nutrition of the myocardium, when it occurs to me that some of you might very naturally ask me: What about fatty degeneration and the treatment of it? This is a question peculiarly interesting to me. I have not dwelt on fatty degeneration of the heart in these lectures, and yet I have mentioned it again and again. I have said that it is a result of alcoholism, of gouty atheroma of the coronaries, of syphilitic arteritis in the same area, of Bright's disease, of profound anæmia and of phosphorus poisoning; and that I believe it may result from severe nervous strain of a harassing and depressing character; and that in connection with each of these causes it has to be regarded and treated differently. Nothing could well bring home more fully to us the importance, indeed the necessity, of pursuing in practice the line of inquiry, prognosis and treatment which I have advocated in these lectures--the etiological one. Let me ask you also to listen to a confession of one of the highest authorities on heart disease in this country. "It is absolutely impossible," says Dr. George Balfour, "to diagnosticate fatty degeneration of the heart; we may surmise its existence, but we can only be certain of its presence when we see it _post mortem_"; and he quotes Fraentzel of Berlin in support of his statement.[16] It must have occurred to many of you, as it has occurred to me, how seldom we diagnose fatty degeneration of the heart until after sudden death. How can we be expected to do so if we trust only to signs and symptoms, and overlook that which is the key to the diagnosis--the discovery of the cause that is at work? [16] Balfour, _op. cit._, p. 249.