INDEX 



411 



Ear, 377 



Edison, Thomas, 32, 33 



Electric measuring instruments 



ammeter, 364 



voltmeter, 364 



wattmeter, 368 

 Electric units 



ampere, 364 



kilowatt hour, 368 



volt, 364 



watt-hour, 369 

 Electricity, circuit, 366 



control of, 246 



electric bell, 349 



electric cells, properties of, 361 * 



electric currents, 348, 360, 364 



electric heating devices, 354 



electric iron, 356 



electric toaster, 356 



electrical toys, 387 



electromagnets, 345, 349 



in the home, 345, 360 



measuring of, 364, 368 



pressure of, 363 



production of, 362 



relation to lighting, 246 



resistance to, 362 



static, 386 

 Electromagnet, description of, 345 



how to make, 349 

 Elytra, 323 

 Emulsion, 234 

 Energy, 52, 338 



electricity and heat, 355 



from food, 94 



sun source of, 52 

 Environment, 40 



scoring of, 55 



Enzymes, relation to digestion, 102 

 Exercise, 33, 34 



Expiration, relation to breathing, 62 

 Extinguisher, fire, 213, 215 

 Extinguishing, burning fat, 214 



gasoline, 214 

 Eyes, adaptation, 260, 264 



care of, 264 



change in the pupil, 259 



control of, 260 



defects of, 260 



importance of, 31, 253 



section of, 258 

 strain, 26 



Eyes Continued 

 structure of, 257 

 testing of, 262 



Fabric, effect of chemical reagents, 



231 



Fainting, 73 

 Farsightedness, 261 

 Fats, 94 



tests for, 96 

 Faucets, leaky, 85 



types of, 84 

 Feet, care of, 224 

 Fireless cooker, 112 

 Fire, 211 



chemical extinguishers, 213, 215 



dangers of, 206, 210 



extinguishing, 212 



flames for light, 209 



losses, 207 



prevention of, 205 



regulation of, 190 



smothering, 212 



sources of, 208 

 Fire-making, 183 

 Flax, 228 

 Fleas, 137 

 Flush tank, 150 



how it works, 151 

 Fly, house (Diptera) 



extermination of, 134 



life cycle of, 134 



relation to home, 132 



trap, 135 

 Focusing, 259 

 Food chart, dietary, 106 

 Foods, 53 



affected by bacteria, 120 



animal origin, 98 



bulky foods, 164 



carbon and water in, 93 



classification of, no 



economy of, 105 



flavors of, 127 



indigestible, 164 



plant origin, 97 



preparation of, 99 



preservation of, 121 



relation to health, 99, 165 



simple foods, 164 



spoiling of, 116 

 Footpound, 339 



