viii CONTENTS 



PAbC 



joint movements Production of energy Nerve control 

 Tonicity Voluntary muscles Involuntary muscles 

 Comparison of voluntary and involuntary muscles Heart 

 muscle Effect of work Influence upon other organs . . 40 



CHAPTER V 



MOTION AND LOCOMOTION 



Simple forms of movement More complex forms Definition 

 of lever Law of leverage Classes of levers Leverage 

 in animal bodies Examples of levers of the first class 

 Examples of the third class Body as a weight Power 

 exerted by the muscles Locomotion Energy expended 51 



CHAPTER VI 



MUSCULAR WORK 



Influence of muscular activity upon development Play Ex- 

 ercise Work Disadvantages of work Fatigue Rest 

 Recuperation 61 



CHAPTER VII 



SELECTION AND PREPARATION OF FOODS 



Foods Carbohydrates Hydrocarbons Proteids Animal 

 manufactures Diets of animals Selection of diets 

 Adjustment of teeth to diet Of stomach and intestines 

 Diet of man Relation of food to muscular energy 

 Primitive cooking Boiling Effects of cooking 65 



CHAPTER VIII 



FOOD MATERIALS 



Plant foods Bread Patent breakfast foods Vegetables 

 Dangers of raw vegetables Potatoes Fruits Preserved 

 fruits Animal foods: milk Contamination of milk 

 Effect of temperature Eggs Meats and fish Parasites 

 in meat Putrefaction Meat stews Soups Fish Con- 

 diments Salt Sugar 73 



CHAPTER IX 



WATER AND OTHER BEVERAGES 



Mineral contents Organic contents Water supply Surface 

 water Spring water Well water Lake water Protec- 



