Dr. Nuzum prepared these essays as a series of informal talks to the public, making understandable the relationships of the heart, the kidneys and the blood vessels and indicating their influence in determining the length of human life. Whereas the vast majority of deaths in a previous generation were due to infectious diseases, the great number of deaths today are due to breakdown of the heart, the kidneys and the circulation. The greatest opportunity to increase the length of life still further depends on an understanding of the work of these organs and on the cooperation of the patient with the doctor in the hygiene of these organs. Dr. Nuzum has written in a manner which any intelligent reader can understand. His work should be exceedingly useful for reference by physicians to patients who need this advice in their cooperation.