INDEX 



401 



Iodine, 69, 268 



Iron, 69, 140, 268, 291 



Irrigation, *294-303; source of 



water, 301 

 Isobars, *41-48 

 Isotherms, *41-48 



"Job's Coffin," 273 

 Jupiter, 263, 256, 257*, 258 



Kerosene, 111, 140 



Lake breezes, 143, 144 



Lake cities, origin of, 155-156 



Lake climate, effects of, 150-151 



Lamps, incandescent, 213*, 240 



Land and water, cooling of, 147; 

 heating of, *145-147 



Land breeze, 145 



Lead, 69, 119, 140, 268 



Lead storage cell, 220*, 222 



Leaf, interior of, 80; structure of, 

 *78-81 ; sugar and starch in, 84 



Leo, 276 



Leprosy, 95 



Lesser Dog, 273 



Life upon the earth, *315-395; in 

 the soil, 312-314 



Life-saving stations, 158 



Light as source of energy, 82-83 



Light and heat from electric cur- 

 rents, *195-216 



Lighthouses, 6*, 158 



Lime in water, 161 



Limewater, 71 



Lines of force, 226 



Liquids and molecular theory, 62 



Little Dipper, 276 



Loam, 288 



Lockjaw, 95 



Low-pressure centers, *39-49 



Lumbering, 318*, 319* 



Lye, 161 



Lyra, 276, 278 . 



Machine, human body compared to, 

 356-357 



Machines, *177-182, *187-191 



Madison, temperature of, 143 



Magnesium, 69 



Magnet produced by electric cur- 

 rent, 227 



Magnetic poles, 224-225* 



Magnets, artificial, 226 ; uses of per- 

 manent, 224-226 



Magnitudes of stars, 269 

 Malaria, cause of, 108 

 Mammals, reproduction of, 369 

 Mammoth Cave, Kentucky, 282 

 Manganese, 69 

 Marble, 72 

 Mars, 253, *254-256 

 Mastication, 357-358 

 Matter, states of, 117 

 Measurement of work, 181 

 Mechanical energy and heat, *183- 



Melting points, 119 



Mercurial barometer, 9, 10* 



Mercury (mineral), 9. 10 14 69 

 140 



Mercury (planet), 252, 253 



Mesophyll, 79, 80, 81 



Metal plating, 218*, 219 



Meter dials, types of, 208* 



Methods of working, 175 



Milk, importance of pure, 100-102 



Milky Way, 277*, 278 



Milwaukee, temperature of, 143 



Mineral salts, 329, 330 



Mixtures of gases, 61 



Mold, 89, 91 



Molecular theory, 60-62 



Molecules, 60-62, 67, 246 



Mont Blanc, 115 



Moon, *243-251 ; atmosphere on, 

 246 ; climate of, 248 ; climatic 

 effects of, on the earth, 245 ; dis- 

 tance and size of, 245-246; light 

 received from, 244-245 ; phases 

 of, 244; water on, 246 



Morning glory, overproduction of, 

 375 



Mosquitoes, destruction of, 111; 

 kinds of, *109-112 ; life history of, 

 *109-110; and malaria, 108-112 



Motion-picture machine, 214 T 215*, 

 216 



Motor, essential parts of, 234* ; differ- 

 ent kinds of, 235 ; uses of, 235-236 



Mount Rainier, 13*, 116*, 283* 



Mushrooms, 91* 



Natural selection, results of, 389 



Nebula, 274* 



Neptune, 253, 260-261 



New York City, water supply of, 



164* 



Niagara Falls, 173, 174* 

 Nickel, 69, 268 



