CONTENTS 



CHAPTER I 



MAN AND NATURE 



The Conquest of Nature, p. 4 Man's use of Nature's gifts, p. 6 

 Man the "tool-making animal," p. 7 Science and Civilization, p. 8 

 Clothing and artificially heated dwellings of primitive man, p. 

 10 Early domestication of animals, p. n Early development 

 to the time of gunpowder, p. 12 The coming of steam and elec- 

 tricity, p. 15 Mechanical aids to the agriculturist, p. 19 The 

 development of scientific agriculture, p. 20 Difficulties of the early 

 manufacturer, p. 21 The development of modern manufactur- 

 ing, p. 24 The relation of work to human development, p. 25 

 The decline of drudgery and the new era of labor-saving devices, 

 p. 27. 



CHAPTER II 



HOW WORK IS DONE 



Primitive man's use of the lever, p. 29 The use of the lever as con- 

 ceived by Archimedes, p. 21 Wheels and pulleys, p. 32 Other 

 means of transmitting power, p. 35 Inclined planes and derricks, 

 p. 37 The steam-scoop, p. 38 Friction, p. 35 Available sources 

 of energy, p. 41. 



CHAPTER III 



THE ANIMAL MACHINE 



The oldest machine in existence, p. 43 The relation of muscle to 

 machinery, p. 44 How muscular energy is applied, p. 44 The 

 two types of muscles, p. 45 How the nerve-telegraph controls the 

 muscles, p. 47 The nature of muscular action, p. 45 Applica- 

 tions of muscular energy, p. 52 The development of the knife 

 and saw, p. 53 The wheel and axle, p. 55 Modified levers, p. 57 

 Domesticated animals, p. 59 Early application of horse-power, 

 p. 60 The horse-power as the standard of the world's work, p. 61. 



