This discussion of the theory and application of ultrasound in biologic sciences is intended to bridge the gap between ultrasonic technology and medicine. Chapters include the diverse uses of ultrasound, including its role in diagnosis, surgery, surgical instrument cleaning, and liberation of cell constituents. It is a comprehensive review replete with circuitry diagrams, mathematical formulas, and explanatory diagrams. There are excellent presentations of physical principles. The text is designed primarily for hospital physicists rather than clinicians.