PREFACE THE situation of the British Isles is such that the weather is uncertain and variable. Whilst in some parts of the world it is possible to fix a date months ahead for an out- door festival with the sure knowledge that there will be sunshine, no such thing is possible in these islands. Yet there are certain laws which the course of the weather follows. This book does not profess to be a complete course of Meteorology. It is hoped, however, that a study of its pages will give added interest and a better understanding of the various types of weather. The weather is always with us. It provides scope for one of the most easily practised forms of nature study for the pupils of all schools, whether in town or country. I Modern man-Savage man-Explorers-Airmen, etc.- History of the study of weather-Astrologers-The Greeks- Galileo-Torricelli-Rain gauges-Balloons and bites-Ex- planations-Charts and maps-Buys Ballot-Recent research CHAPTER I1 THE ATMOSPHERE . I2 What is air-Chief gases-Oxygen-Nitrogen-Breathing and carbon dioxide-Plants-Water vapour-Other gases- Dust - Weight - Pressure of gases - Pressure of air- Climbing a mountain-Aeroplanes-Ballon-sonde-Pilot balloons - Records -Troposphere -Stratosphere - Height of atmosphere-Barometers--Types of barometers-Fortin -Kew-Aneroid-Barographs-Measurement of Pressure -Millibars-Corrections CHAPTER I11 THE SUN AND THE EARTH . 33 The travelling earth-The sun-Heat of sun-Insulation- Earths shape-Latitude-Earths axis and seasons-Solstices-Equinoxes-How does the sun warm the earth- Convection-Radiation-Thermometers-What they measure-Scales-Fixed points-Weather temperatures-Stevenson screen-Maximum and minimum thermometers-Sixs thermometer-Reading thermometers CHAPTER IV WINDS 9 Cause-Room and draughts-Ventilation-Wind or current -Direction- Judging direction-Weather vane-Speed of wind - Beaufort - Beaufort scale - Anemometers - Great winds of the world-Why caused-Trade winds-Ferrels Law - Anti-trades - High pressure regions - MTesterlies - Land and sea breezes-Monsoons vii CONTENTS CHAPTER V PAGE MOISTURE IN THE ATMOSPHERE . 78 Puddles-Evaporation-Latent heat-Unit of heat-Calorie -Condensation-Saturation-Cooling-Dew-point-Humid- ity-Measurement of relative humidity-Finding dew-point -Hygrometers-Dew-Hoar frost-Preventing frost-Fog and mist-Fogs at sea-Eddy currents-Fog on land-Pre- dicting fogs-Visibility-Causes affecting visibility CHAPTER V1 CLOUDS AND RAIN 96 What is a cloud -Cloud shapes-Types of clouds-Cloud heights-Nephoscopes-Amount of cloud-Sunshine recor- ders-Rain-Size of drops-Velocity of drops-snow- Glaciers-Perpetual snow-Sleet-Hail-Measurement of rain and snow-Gauges-Weight of rainfall CHAPTER V11 MAKING WEATHER CHARTS . . I22 System-Observation stations-The growing map-Strange isobars-Cyclone-Anticyclone-Secondaries-shaped de- pressions-Wedge of high pressure-The Col-Straight isobars-Temperature CHAPTER V111 WEATHER FORECASTS . . I32 Weather reports-The expert and how he works-The amateur forecaster-Apparatus-Lines along which to work -Forecasting with a barometer CHAPTER IX CURIOUS WEATHER PHENOMENA . . 142 Thunderstorms-Anvil-shaped cumulus-Cause of lightning -Two kinds of electricity-Rushing raindrops-lightning- Distance of storm-Line squalls-Hurricanes-Tornados CHAPTER X WEATHER LORE AND PROVERBS . I49 The sky-Rainbow-The moon-Seaweed, etc.-Summer and winter-St. Swithin-Birds and animals CHAPTER XI POETS AND THE WEATHER 1.54 ILLUSTRATIONS PAGE Crossing a Glacier , 2 Korean Rain-gauge . . 6 Heights of Adventurers . g Dustless Air . . . . 16 Pass of Glencoe . . 18 Kite and Meteorograph . 20 Air Pressure . - 23 Diagonal Barometer . 24 Fortin Cistern . 25 Diaphragm of Aneroid . 26 Aneroid Movement . 27 Barograph ...