This 1985 textbook presents the theory of thermodynamics in a highly interesting way. The presentation of the theory of heat is logical, compact and uncluttered, with an emphasis on the underlying physical model. Unlike other texts published at this time, in this approach the student adopts at the outset the master equation which describes the rate of scattering from one quantum state into another. This makes the link between thermodynamics and kinetics more obvious. Temperature and entropy are initially introduced as statistical concepts. Unlike most other treatments, this book has early sections on the Boltzmann distribution and classical thermodynamics, which may be used as a basis for first-year courses. The book also contains extensive graded exercises.