CONTENTS 



PAGE 

 I. SOME LESSONS ON THE HUMAN BODY. 



The Hand 2 



The Mouth 4 



The Eye 10 



II. HEAT IN RELATION TO THE HUMAN BODY. 



Combustion 16 



Pure Air, and Breathing 19 



The Human Body as an Engine, and the Regulation of Body 



Temperature 25 



III. HEALTH AND WELL-BEING. 



Keeping Well 31 



Infection 36 



Sanitation 45 



The Water Supply and Health 52 



General Health Problems 57 



Life, Growth, Rest, and Recreation 64 



Stimulants and Narcotics 72 



General Science and Right Living 80 



IV. WATER AND ITS USES. 



Some Properties of Water 85 



Vaporization and Condensation 90 



Heat of Vaporization and of Fusion 94 



Solution, Diffusion, Absorption, and Osmosis 97 



Streams, Valley Formation, and Surface Erosion 102 



V. THE ATMOSPHERE. 



Properties and Uses of Air no 



Pressure Exerted by the Atmosphere, and Effect of Pressure on 



Gases 114 



Applications of Atmospheric Pressure 118 



Currents in the Atmosphere, and Their Relation to Atmospheric 



Pressure 123 



Areas of High and Low Pressure 128 



ix 



