This volume presents an original, synthesizing approach to the thermal physics of fluid continua based on a novel extension of Hamilton's principle which allows the free flow of entropy, independent of that of matter. The extension, used in the context of Nother's theorem of variational calculus, gives rise to heat and diffusion terms in the conservation laws for the energy, momentum and matter, and may include the effects of thermal inertia. The mass conservation in reacting systems results from their intrinsic symmetries. The role of thermodynamic irreversibility can be investigated through...