CONTENTS 



CHAPTER PAGE 



1. THE PRODUCTION AND USE OP LIGHT 1 



II. THE PRODUCTION AND USE OP HEAT 71 



III. REFRIGERATION AND ITS USES 154 



IV. THE WEATHER 176 



V. THE SEASONS CLIMATE AND HEALTH 281 



VI. VENTILATION 311 



VII. FOOD AND NUTRITION 343 



VIII. MICROORGANISMS 380 



IX. SOIL PHYSICS, WATER SUPPLY, AND SEWAGE DISPOSAL. . 450 



X. MACHINES, WORK, AND ENERGY 518 



APPENDIX. WEIGHTS AND MEASURES 585 



GLOSSARY 589 



INDEX . . 599 



vii 



