From Introduction: "The recent acceptance by physicists and chemists of new values for the fundamental constants and the continued demand for expanded and convenient tables prompted the recomputation and preparation of this volume. The authors have tried to incorporate this work a number of the more desirable features of the above-cited works, particularly with respect to their use in calculations involving: Thermodynamic properties of gases; specific heats, electrical and thermal conductivity of solids; and molecular structure and spectroscopy of diatomic and polyatomic molecules. It is the hope of the authors that formal character of this publication will insure a more adequate notice and dissemination than was accorded the earlier works, thereaby reducing the probability of still further duplication of effort."