An absolutely vegetarian diet is the first requisite in the treatment and prophylaxis of cancer, for, as mentioned, this has been found experimentally to inhibit, often to a remarkable degree, the production of artificially produced cancer in rats and mice, and experience throughout the world has shown cancer to be extremely rare in vegetarians. This diet, which should be maintained indefinitely, must be rigorous and absolutely vegetarian, excluding animal protein, even eggs and milk; butter is the only article allowed which does not grow, and of this one quarter of a pound is to be taken daily, by a person weighing 150 pounds. Cereals are to be freely employed, eaten slowly, with a fork, and with butter, and not with milk and sugar, though the latter may be used moderately, where it seems necessary and where it perfectly agrees with the patient. Perfect mastication, with thorough insalivation, is very essential, and I insist on at least half an hour being taken for even the lightest meal. Coffee, chocolate, and cocoa are excluded from the diet, only weak tea being allowed, with some postum or other artificial substitute for coffee. Alcohol in each and every form is absolutely excluded, as it always has a very harmful effect on cancer. Sufficient water, not iced, should be taken to answer to the needs of the system, and I commonly give half a pint with each meal, and half a pint, hot, one hour before both breakfast and the evening meal. Cancer being a disease of advancing civilization, with all its temptations and errors in living, it is essential that the cancer subject lead a very simple and healthy life, with regular hours of eating and sleeping, with a reasonable amount of exercise, and the avoidance of everything which could disturb normal metabolism. There is, of course, no single medicine which can cure cancer, but proper medication plays a very important part in overcoming the disease and should never be neglected or interrupted in any case; indeed, one suffering from or threatened with cancer should be under the most careful medical guidance indefinitely, and this is especially true after the surgical removal of the tumor, or local manifestation of the morbid process, as Abernethy so strongly asserted, nearly a hundred years ago.