The aim, then to be sought in the prophylaxis of cancer is to secure the most perfect blood stream possible, which is accomplished by simple living, perfect mastication, and the avoidance of excesses, especially along the lines of protein, tea and coffee, alcohol, etc., with the maintenance of healthy habits of life, especially in regard to bowel action. As already intimated, we do not know just why in some persons and at a certain time a disturbance of metabolism results in perverted cell growth, but there is, of course, a reason, and the physician’s duty is so to regulate the patient’s whole life that the metabolism is kept in the state of perfect health. All this seems very simple and trite, but really it is a task which is most important and often most difficult to accomplish, and requires very careful study and infinite patience. Dr. Kellogg, of Battle Creek, says that of the many thousands who have passed under his care he has not known cancer to develop in any one who had been faithful to the principles which he inculcates, and I may say the same of the many who have been under my care in private practice, often with notes extending over many years. Time does not permit of going into detail here in regard to the special features of diet and hygiene, which I discussed with you fully two years ago, in my lectures, which were subsequently published: suffice it to say, as previously remarked, that the refinements of civilization add greatly to the temptation of over-eating, and wrong eating and drinking, as they do to numerous other temptations, and in many instances it requires the utmost amount of grit as well as patience, both in the patient and doctor, to secure the perfect result necessary.