It is needless to say that there is nothing original in the book unless it be in part the grouping of facts and order of their treatment. I have made free use of the writings of Rutherford, Soddy, and J. J. Thomson, and would here express my debt to them—just a part of that indebtedness which we all feel to these masters. I wish also to acknowledge my obligations to Professor Bertram B. Boltwood for his helpful suggestions in connection with this work.
CONTENTS
| [CHAPTER I] | |
| DISCOVERY OF RADIO-ACTIVITY | PAGE |
| The beginning—Radio-active bodies—An atomic property—Discoveryof new radio-active bodies—Discovery of Polonium—Discoveryof Radium—Other radio-active bodies found | [1] |
| [CHAPTER II] | |
| PROPERTIES OF THE RADIATIONS | |
| Ionization of Gases—Experimental confirmation—Application ofelectric field—Size and nature of ions—Photographing thetrack of the ray—Action of radiations on photographic plates—Dischargeof electrified bodies—Scintillations on phosphorescentbodies—Penetrating power—Magnetic deflection—Threetypes of rays—Alpha rays—Beta rays—Gamma rays—Measurementof radiations—Identifications of the rays | [7] |
| [CHAPTER III] | |
| CHANGES IN RADIO-ACTIVE BODIES | |
| Radio-activity a permanent property—Induced activity—Discoveryof Uranium X—Conclusions drawn—Search for new radio-activebodies—Methods of investigation—Nature of theradiations—Life-periods—Equilibrium series | [17] |
| [CHAPTER IV] | |
| NATURE OF THE ALPHA PARTICLE | |
| Disintegrating of the elements—Identification of the rays—Thealpha rays—Alpha rays consist of solid particles—Electricalcharge—Helium formed from alpha particles—Discovery ofHelium—Characteristics of Helium—Table of constants | [25] |
| [CHAPTER V] | |
| THE STRUCTURE OF THE ATOM | |
| Properties of Radium—Energy evolved by radium—Necessity for adisintegration theory—Disintegration theory—Constitutionof the atom—Rutherford's atom—Scattering of alpha particles—Stoppingpower of substances | [32] |
| [CHAPTER VI] | |
| RADIO-ACTIVITY AND CHEMICAL THEORY | |
| Influence upon chemical theory—The periodic system—Basis of theperiodic system—Influence of positive nucleus—Determinationof the atomic number—Use of X-ray spectra—Changes causedby ray-emission—Atomic weight losses—Lead the end product—Changesof position in the periodic system—Changes fromloss of beta particles—Isotopes—Radio-activity in nature—Radio-activeproducts in the earth's crust—Presence in air andsoil waters—Cosmical radio-activity | [41] |
| [Index] | [53] |