This book is sold subject to the condition that it shall not, by way of trade, be lent, resold, hired out, or otherwise disposed of without the publisher's consent, in any form of binding or cover other than that in which it is published (3046/67) ## Preface A L T H O U G H it is well known that for a proper discussion of atomic properties one needs wave mechanics and that the old quantum theory developed by Bohr, Sommerfeld, Kramers and many others between 1913 and 1926 is not a proper basis, there are many atomic phenomena which receive at least a qualitative explanation in the old quantum theory. An account of this theory seems therefore to be of some interest and in the present volume we sketch how it developed from Planck's first papers on black-body radiation through Einstein's and Rutherford's work to the rather complicated theory which was finally replaced by Schrödinger's wave mechanics and Heisenberg's matrix mechanics. I should like to express my thanks to Professor R. E. Peierls for useful criticism, to Mrs. D. Gordon of the Yale Physics Department for her help in locating the relevant literature, and to my wife for help in preparing the manuscript. This book was written during a stay at Yale, and I should like to express my gratitude to Professor W. E. Lamb, Jr., and to other members of the Yale Physics Department for their hospitality. Finally, I express my thanks to the authors and publishers of the papers reprinted in Part 2 for their permission to do so. Content: Front Matter , Page iii Copyright , Page iv Preface , Page vii Introduction , Pages ix-x CHAPTER I - The Black Body Radiation Law , Pages 3-14 CHAPTER II - Light Quanta , Pages 15-24 CHAPTER III - Rutherford's Atom , Pages 25-33 CHAPTER IV - Bohr's Atom , Pages 34-42 CHAPTER V - Atomic Spectra in the Old Quantum Theory , Pages 43-62 CHAPTER VI - Radiation Theory , Pages 63-72 References , Pages 73-75 1 - On an Improvement of Wien's Equation for the Spectrum , Pages 79-81 2 - On the Theory of the Energy Distribution Law of the Normal Spectrum , Pages 82-90 3 - On a Heuristic Point of View about the Creation and Conversion of Light , Pages 91-107 4 - The Scattering of α and β Particles by Matter and the Structure of the Atom , Pages 108-131 5 - On the Constitution of Atoms and Molecules , Pages 132-159 6 - On the Excitation of the 2536 Å Mercury Resonance Line by Electron Collisions , Pages 160-166 7 - On the Quantum Theory of Radiation , Pages 167-183 8 - On the Connexion between the Completion of Electron Groups in an Atom with the Complex Structure of Spectra , Pages 184-203 Index , Pages 205-206
