Indeed, when viewed in a broad philosophical light it may not be the best course for mankind to shun all dangers. Strength in the organism comes from the use rather than the disuse of our powers. It is certain that the general health and vigour of mankind is to be developed by meeting rather than by shunning dangers. Resistance to disease means bodily vigour, and this is to be developed in mankind by the application of the principle of natural selection. In accordance with this principle, disease will gradually remove the individuals of weak resisting powers, leaving those of greater vigour. Parasitic bacteria are thus a means of preventing the continued life of the weaker members of the community, and so tend to strengthen mankind. By preventive medicine many a weak individual who would otherwise succumb earlier in the struggle is enabled to live a few years longer. Whatever be our humanitarian feeling for the individual, we can not fail to admit that this survival of the weak is of no benefit to the race so far as the development of physical nature is concerned. Indeed, if we were to take into consideration simply the physical nature of man we should be obliged to recommend a system such as the ancient Spartans developed, of exposing to death all weakly individuals, that only the strong might live to become the fathers of future generations. In this light, of course, parasitic diseases would be an assistance rather than a detriment to the human race. Of course such principles will never again be dominant among men, and our conscience tells us to do all we can to help the weak. We shall doubtless do all possible to develop preventive medicine in order to guard the weak against parasitic organisms. But it is at all events well for us to remember that we can never hope to develop the strength of the human race by shunning evil, but rather by combating it, and the power of the human race to resist the invasions of these organisms will never be developed by the line of action which guards us from attack. Here, as in other directions, the principles of modern humanity have, together with their undoubted favourable influence upon mankind, certain tendencies toward weakness. While we shall still do our utmost to develop preventive medicine in a proper way, it may be well for us to remember these facts when we come to the practical question of determining where to draw the limits of the application of methods for preventing infectious diseases. CURATIVE MEDICINE. Bacteriology has hitherto contributed less to curative than to preventive medicine. Nevertheless, its contributions to curative medicine have not been unimportant, and there is promise of much more in the future. It is, of course, unsafe to make predictions for the future, but the accomplishments of the last few years give much hope as to further results. DRUGS.