Besides this the most important element in treatment he considers to be the encouragement of the appetite--as might be expected from the man who first fed fevers. His directions in this matter are very explicit, and he suggests various methods by which patients can be tempted to eat more and more food, and emphasizes the use of cereals and of milk and eggs as likely to be of most service in helping these patients to gain in weight and strength so as to be able to resist the further advance of the disease. This, it may be said in passing, is just the ideal treatment for the consumptive at the present time. Others of Graves' opinions in regard to tuberculosis are in general surprisingly modern. He insists, for instance, that the main causes of the disease are overcrowding in towns, the long hours of hard work in factories, and abuse of alcohol. He thought that the population of country places, though fed no better as a rule than in the city, do not develop the disease so frequently because of their opportunity for fresh air. He placed very little confidence in the opinion that cold has anything to do with tuberculosis, though he disputed Laennec's dictum that bronchitis was never the beginning of tuberculosis. Graves advises his students not to try to {175} protect their throats by means of mufflers, for this will only render them more liable to cold. His advice is rather to harden themselves against cold. For this he suggests the use of water plentifully on the chest and throat, to be employed not too cold during the winter time, unless one is used to it. He also suggests the use of vinegar and alcohol as hardening fluids. They should be applied freely, and in his experience were effective. Another interesting anticipation of modern methods was with regard to child feeding in summer diarrhoea. It is often thought that only in recent years, with the development of the science of bacteriology, the danger of continuing milk feeding when infants are already ill in the summer has come to be recognized. Milk is now known to be an excellent culture medium for various forms of bacteria, that is, it is a substance on which microbes grow plentifully, and it is often used in the laboratory to raise microbes. Dr. Graves, however, without any knowledge of modern bacteriology, but from clinical observation alone, pointed out that the only way to avoid summer diarrhoea is to stop all milk feeding. "Let the infant," he says, "abstain from milk in any shape for twenty-four hours, sometimes for the space of two or even three days. It is incredible how small a portion of milk, even in the most diluted state, will keep up this disease, acting like a species of poison on the intestinal mucous surface."