CONTENTS. 



PAGE 



I. Historical Introduction 5 



II. The Structure of Fluorescence Spectra 10 



III. Preliminary Observations on Certain Uranyl Salts 15 



IV. Phosphorescence of the Uranyl Salts 38 



V. Intimate Structure on Cooling to 185 C 61 



VI. Polarized Spectra of Double Chlorides 102 



VII. The Nitrates and Phosphates; Water of Crystallization; Crystal Form 122 



VIII. The Acetates 146 



IX. The Sulphates 169 



X. Frozen Solutions 180 



Appendix 1. Chemistry and Crystallography of the Uranyl Salts 207 



Appendix 2. On Phosphoroscopes 231 



3 



