In addition to the meteorologist and the artist, there are a much larger number who follow neither profession, but who love Nature in all her moods; and to them also I hope these pages may be of interest. Indeed, if only a few of them should be stimulated to take up a branch of nature study which has given me many an hour of quiet enjoyment, the labour of bringing these notes together will not have been in vain. ARTHUR W. CLAYDEN. St. John’s, Exeter. CONTENTS CHAPTER PAGE I. Introductory 1 II. Cirrus 21 III. Cirro-stratus and Cirro-cumulus 45 IV. Alto Clouds 59 V. Lower Clouds 71 VI. Cumulus 84 VII. Cumulo-nimbus 105 VIII. Wave Clouds 119 IX. Cloud Altitudes 137 X. Cloud Nomenclature 154 XI. Cloud Photography 165 References 181 Index 183 LIST OF ILLUSTRATIONS PLATE PAGE A Sunset Sky _Frontispiece_ 1. Part of a Great Halo 22 2. Part of a Solar Halo 23 3. Cirro-nebula changing to Cirro-stratus 24 4. Cirro-nebula changing to Cirro-cumulus 27 5. High Cirrus. (_Cirrus Excelsus_) 31 6. Windy Cirrus. (_Cirrus Ventosus_) 32 7. Thread Cirrus. (_Cirro-filum_) 34 8. Tailed Cirrus. (_Cirrus Caudatus_) 35 9. Hazy Cirrus. (_Cirrus Nebulosus_) 36 10. Change Cirrus. (_Cirrus Inconstans_) 37 11. Common Cirrus. (_Cirrus Communis_) 40 12. Band Cirrus. (_Cirrus Vittatus_) 41 13. Band Cirrus. (_Cirrus Vittatus_) 42 14. Hazy Cirro-stratus. (_Cirro-stratus Nebulosus_) 46 15. Cirro-stratus 47 16. Cirro-stratus. (_Cirro-stratus Communis_) 48 17. Flocculent Cirro-stratus. (_Cirro-stratus Cumulosus_) 49 18. Cirro-stratus and Cirro-cumulus 50 19. Cirro-cumulus 50 20. Hazy Cirro-cumulus. (_Cirro-cumulus Nebulosus_) 51 21. Hazy Cirro-cumulus. (_Cirro-cumulus Nebulosus_) 51 22. A Sunset Sky 52 23. Speckle Cloud (Ley). (_Cirro-macula_) 53 24. Cirrus Caudatus and Cirro-macula 55