CONTENTSPageI.Introductory5All Matter Radioactive9II.Everyday Uses of Radium16Radium Makes Gems Blush18A Radium Clock19III.Radium and the Age of the Earth21IV.An Epoch-Making Discovery30How Radium is Converted to Lead34V.Radium in the Treatment of Cancer45VI.Efficiency of Radium in Treatment of Various Diseases51VII.Where We Get Radium55New Sources of Radium58The Radioactive Disintegration Series60Uranium I Series63Uranium Y Series63Thorium Series64