This is not a book about heart disease, bypass surgery, or balloon angioplasty. It is not a book about how to change your habits and become fit and slim and heart-healthy (although the author confesses to having had a heart attack and having changed his lifestyle). It is a book about how your heart and circulatory system work--their normal physiology--told by a professor of zoology at Duke with a love for comparative anatomy and--well, plumbing. Yes, Vogel's great gift in this lucid exposition is to explain how the pumps (the right and left sides of the heart are essentially two pumps that work together) and the pipes (the arteries and veins) and the blood they supply to all the body's cells obey classic laws of fluid dynamics. So there is much here that will appeal to the home handyman and the physics student as well as to those naturally curious about the way things work. Forced convection, laminar flow, principles of continuity, and numerous eponymous laws (Bernoulli, Pascal, Laplace) are all invoked to explain the beauty of a system that is indeed vital to survival. Among the curiosa: Small animals have shorter lives and more rapid heartbeats than larger animals, but, generally speaking, the total number of heartbeats per lifetime in mammals is a constant: one billion. Also, did you know that flow rate is moat rapid at the center of a pipe and is zero at the walls? That explains why fan blades get dirty: Air doesn't flow at the surface so they collect dust. All this and more await the intelligent science reader who would like time out from all those books on genes and biotechnology for some fine old-fashioned whole-organ physiology.