XXU CONTENTS 



CHAPTER XI 



PAGE 



ELECTRICITY 385 



Measuring Instruments. Magnets. Motors. Generation of Elec- 

 tricity. Thunder Storm. Ohms. Fuses. Electroplating. Elec- 

 trolytic Method of Cleaning Silver. Use of Magnets and Cells. 



CHAPTER XII 

 THE RELATION OF SOUND AND Music TO Us 411 



Sound. Source of Sound. Ear. Echo. Speed of Sound. Reso- 

 nance. Sympathetic Noise. Wood in Musical Instruments. Pho- 

 tographs of Tones. Piano Strung-back. Harp. Pipe Organ. Piano 

 Player. Phonograph. Telephone. 



CHAPTER XIII 

 THE UNIVERSE 443 



Laws of Matter. Molecules. Cohesion. Adhesion. Capillarity. 

 Indestructibility. Gravity. Gravitation. Location. Direction. 

 Longitude. Latitude. International Date Line. Standard Time. 

 Heavenly Bodies. The Planets. The Stars. Constellations. 



CHAPTER XIV 

 MACHINES AND WORK 491 



Simple Machines. Levers. Compound Machines. Mechanical 

 Advantage. 



CHAPTER XV 



"SAFETY FIRST" : 504 



Cause and Prevention of Accidents. Sinking. Taking Chances. 

 Dangers in and about the Home. Use of Gasoline and Benzine. 

 Dangers Outside the Home. Emergency Treatment. 



APPENDIX 529 



Dry Measure. Equivalent of Common Capacity Units used in the 

 Kitchen. Tables of Weights and Measures. International Metric 

 System. Approximate Equivalent of the French Metric and English 

 Measures. Metric Measures. Familiar Facts. Weight of Everyday 

 Things. Conversion Table. Preparation of Solutions. 



INDEX . 541 



