Originally published in 1993, this book of essays is a largely nonmathematical account of some of the strange behaviour, both classical and quantum, exhibited by moving particles, fluids and waves. Drawn from the author's researches in quantum mechanics, atomic and nuclear physics, electromagnetism and optics, gravity, thermodynamics, and the physics of fluids, the essays describe different physical systems whose behaviour provokes surprise and challenges the imagination. There are strange processes for which no visualisable mechanism can be given; processes that seem to violate fundamental physical laws, but which in reality do not; processes that are superficially well understood, yet turn out to be subtly devious. The essays address questions or controversies from whose resolution emerge lessons of general significance regarding the mystery and fascination of motion. Anyone with a basic physics background or with an interest in the fundamental questions of physics will find this book of use.