INDEX 



443 



Language, development, 373 



Larvae, 355 



Larynx, 89 



Latent heat, 138 



Latitude, 21 



Lavoisier, 83 



Leaves, 317, 326 



parts of, 326 



as food, 340 

 Leeuwenhoek, 409 

 Legumin, 388 

 Lens, 227, 228, 239 

 Levees, 309 

 Levers, 53-56 

 Levulose, 392 

 Leyden jar, 197 

 Light, 220-234 



properties of, 220 



as energy, 222 



intensity of, 223 



reflection of, 224 



diffused, 226 



refraction of, 226 



composition of, 231 



absorption of, 233 

 Lighting, electric, 202, 244 



in the house, 240 



artificial, 241-244 

 Lightning, 182 

 Lime, 295 



Limestone, 270, 282 

 Liquids, 26 



shape of free, 47 



capillary action in, 49 



transmission of pressure, 112 

 Liter, 32 

 Litmus, 272, 274 

 Little Dipper, 10 

 Living matter, 315 

 Longitude, 21 

 Lumbering, 337 

 Luminous bodies, 221 

 Lungs, 88-89 



Machines, 53-54, 63 

 Magnetism, 186-188 

 Magnets, 186 



earth as, 190 

 Malaria, 429 

 Malleability, 251 

 Maltose, 393 

 Mammals, 360 

 Man, 372-375 

 Mantle, incandescent, 243 



Mars, 2, 3 

 Marsh gas, 262 

 Mass, 34 

 Matches, 265 

 Matter, 26, 246 



forms of, 26 



properties of, 28 



changes in, 246 

 Measles, 427 

 Measurement, 29 



length, 33 



volume, 34 



mass, 34 



temperature, 128 



light, 223 



Mechanical advantage, 63 

 Medullary rays, 324 

 Melting point, 133 



in metals, 252, 255 

 Mercury, planet, 2, 3 

 Mercury, 252 

 Meridians, 20 

 Metals, 250-251 

 Metamorphic rock, 281 

 Meter, 31 

 Metric system, 31 

 Microscope, 229 

 Mildews, 344 

 Milk, 384, 388 



danger from, 413 



pasteurized, 415 

 Mixtures, 247 



Moisture, need of, in the air, 151 

 Molds, 331, 347 

 Molecules, 28, 126 



relation to heat, 137 



relation to light, 220 

 Monsoons, 172 

 Moon, 11, 12 

 Mosquitoes, 429-431 

 Mosses, 329 

 Motors, electric, 211 

 Mushrooms, 330 

 Myosin, 388 



Neptune, 2, 3 

 Newton, Sir Isaac, 37 

 Nimbus clouds, 177 

 Nitric acid, 273, 274 

 Nitrogen, 85 



use in explosives, 86 



importance to plants, 86, 291, 293, 



332 

 Nitroglycerine, 274 



