For a time he failed to see that with changed conditions his health problem had changed. If, as a result, he did not die of consumption or typhoid fever, he became anæmic and dyspeptic, his chest sank, his circulation became impaired, and his liver sluggish. Then he awoke to the fact that if he would have good air he must adopt a system of ventilation for his closed buildings; that if he would have good lung capacity, quick circulation, and an active liver, he must take regular physical exercise; that if he would have safe water, he must stir up the municipal authorities to do their duty or must himself adopt means to sterilize his drinking supply; that if he would have wholesome food, there was something necessary besides good cooking. Dairies and markets must be inspected and laws against adulteration must be made and enforced. Scientists came to his rescue and put at his disposal an abundance of literature on hygiene, sanitation, and physical culture, but he had little time in which to read it. So it has come about that with his altered health problem there has been opened to woman the opportunity to do something more for man’s health than to cook his food. If she is intelligent and has leisure, she can study sanitation and hygiene and make practical application of their principles in her home. She can take lessons in physical culture, pass them on to her husband and exercise with him a few minutes every day, thus helping him to overcome the effects of his sedentary occupation. She can, through her clubs, stir up the town authorities to provide good water, to clean the streets and prevent disease-laden dust from blowing about, to care properly for garbage and sewage, and to inspect places where food is kept for sale. In many ways she can help in the struggle against disease which man made necessary when he became a town dweller.