The title fails to do justice to this excellent book, because it is too narrow. While the greatest emphasis is placed on health in the middle decades, the book is packed with information useful at any adult age. It is a compilation of chapters based on public lectures given by the faculty of the Harvard Medical School, a series of lectures which was inaugurated in 1907 and has been interrupted for only one year, 1919. There are eleven chapters dealing in turn with heart disease, blood pressure, weight control, cancer, rheumatism, the menopause, the eyes, vitamins, glands, the family medicine cabinet and mental health, plus a summarizing chapter by the editor. The material is well authenticated, well selected and well arranged. Unlike many compilations of lecture material in which each chapter is contributed by a different author, this book is not discursive and repetitious, which means of course that it