CONTENTS. CHAPTER I.-THE DISCOVERY OF RADIUM ITS EXTRACTION. Radiation-Kathode Rays-X-Rays-Becquerel Rays-Crookes Discovery - Pitchblende - Extraction of Radium-Its Distribution on the Earth ... ... 11 CHAPTER 1 I . T H E RADIUM EMANATION. The Emanation - Its Nature - Disintegration of the Radium Atom-Its Conversion into eliurn-heo or of Solar Radiation due to Radium-Properties of the Emanation-Effect of Temperature . . . ... ... 22 CHAPTER 111.-PHYSICAL EFFECTS ELECTRICAL AND MAGNETIC. Nature of Rays Emitted by Radium-Ionization-Charge and Magnetic Deviation of p Rays-Charge and Magnetic Deviation of a Ray S-Theory of Atmospheric Electricity and Terrestrial Magnetism Due to Radium 33 CHAPTER 1V.-PHYSICAL EFFECTS continued. Luminous Effects-Spinthariscope - Fluorescent Substances-Thermal Effects-Thermo-luminescence-Penetrative Powers-Absorption of Gravitational Energy-Induced Radio-activity . . . . . . - g 49 CHAPTER V.-CHEMICAL EFFECTS. Effect on Photographic Plates-Colourations of Glass, Paper, etc.-Effect on Solutions of Iodoform in Chloroform-Effect on Compounds of Iodine-Reducing Effect-Molecular Changes Produced-Relation to other Elements-Atomic Weight Determination ... ... ... . . . . . . . . . ... 69 CONTENTS. CHAPTER V1.-ACTIONS ON ANIMAL LIFE AND LIVING TISSUES. Effect on Plants and Seeds-on Spermatozoa-on Ova-on Eggs of the Sea-urchin-on Larvz and Embryos---on Animals of Low Type-Motor Action-on the Eye-on the Skin-on Lupus and Apparatus for Cancer ... . a .. n d C . a . n . cer-R .. a . d ium - W . 77 CHAPTER V11 .-OTHER RADIO-ACTIVE ELEMENTS. Uranium-l ts Extraction-Appearance and Nature-Emanation - Uranium X - Rays Emitted - Their ... a.. Effects ... ... ... ... ... 89 Thoviuwz-Nature - Thorium X-Emanation - Induced Radio-activity-Rays Emitted-Carolinium and Ber-zelium-Connection with Actinium ... ... ... 91 Polonium-Discovery and Extraction-Physical Attributes - Rays Emitted ... ... ... ... ... ... 95 Actinium-Discovery-Emanation-Rays ... ... ... 96 Hofmanns Radio-active Metal ... ... ... - - 97 APPENDIX.-EXPERIMENTAL APPARATUS ... 98 INTRODUCTION. ABOUT sixty years ago, when the first telegraphic lines were erected, people marvelled at the seeming miracle. Later on electric light was invented, and still later the telephone. The last decade has witnessed discoveries which have rendered possible the photography of the bones of a living being the demonstration of the motion of the heart on a screen by x-rays and also the transmission of messages without wires. The latest marvel of science is the discovery of the new series of radio-active elements. The most active and wonderful of these elements which has up to the present been investigated or obtained in sufficient quantity for investigation is called Radium. The properties of Radium, and its allied elements, are so unique and astounding, that this alone is sufficient reason to account for the interest which it has excited. In addition to this, however, radium is reputed to have great therapeutical properties. Experiments are now being carried out, with partial if not complete success, to combat by means of radium diseases hitherto considered incurable. INTRODUCTION. Many articles on radium have appeared in various papers, scientific and otherwise but as yet no complete correlation of the many facts has been published. We have endeavoured to treat the subject in an experimental and practical way, but have not attempted to relate or explain the various theories of the sources of the radiations...