The saving of health is one of the greatest steps that has been made, as it has been suddenly performed within a generation. Man had unconsciously conquered bacteria to a great extent by the invention of cooking, and by the experimental learning of cleanliness; but the scientific attack on bacteria and protozoa has given the prospect of preventing all epidemic disease, and largely increasing the efficiency of man in the most fertile countries. This advance means the economic exploitation of the whole tropical regions, which—with cheap transport—will provide an immense fresh basis for the advantage of other lands. The gain in antiseptic surgery, giving safety for operation on all internal organs, as it only affects the small proportion of sick and injured, is not of so much general importance as the conquest of the microorganisms, which have hitherto ruled the best part of the world. It is in the complete domination over all forms of life, however minute, that we shall find one of the greatest lines for future advance. Only a small band of workers, about one in a hundred million of the world's population, has made this advance possible. The saving of life is another great step which will give man far higher power; not only in the mere hindrance of death, but far more in the increased power of work _per_ day. The power of continuity of work is a growth of civilisation; and it is obvious that a man who can do twelve hours' work _per_ day, instead of six hours, not only lives virtually twice as long, but costs the community only half as much for what he does. This continuity of work, or industry, is seen in both high and low classes of work. Some races can do more than twice as much agricultural work in the day as others. The same is true of scientific or commercial work. And there have been some of the highest minds which could only work for two hours a day, while others could work up to fourteen or sixteen hours daily. This power of continuity of work is obviously then a matter improvable by cultivation, both in the individual and in the race; and as it may easily double a man's effective life it is certainly a line of great promise for the future. Another direction for saving a portion of life is in the rapidity of thought and action. It is easy to find a difference of two or three times the amount of work _per_ hour between different men. All that we have just said about the continuity of work applies to its rapidity; and a large gain may be looked for in cultivating pace and vigour. We need hardly note that trades-union ideals would destroy instead of promoting these most promising and fruitful lines of advance. In transport from place to place the movement at fifty miles an hour instead of five means a gain of several years of life to most men. But here we have probably reached the useful limits, as any possible further saving would not yield much more time.