This book covers a wide range of physical factors and aspects in normal physiologic processes, disease, diagnosis and therapy. Animal calorimetry and the physical chemistry of solutions are presented too simply in view of present knowledge and methods. The gross mechanics of muscle action, locomotion, respiration, blood pressure and circulation are presented satisfactorily for the medical student. Acoustics, optics and electrophysiology are presented in more than usual detail. Biologic reactions to light radiations are considered briefly and generally, but the biologic action and therapeutic application of ultraviolet radiations, x-rays and radon are given in considerable detail. The book may be considered a good elementary presentation of physics as applied to medicine rather than a fundamental textbook on biophysics or general physiology.