INDEX 



Mosquitoes Continued 



life history of, 14, 15, 136 



relation to malaria, 14 



relation to yellow fever, 137 

 Moths, life history of, 319 



relation to clothes, 139 

 Musical scale, 378 

 Music and noise, 378 



Nearsightedness, 260 

 Neutralization, 234 

 Nitrates, relation to soil, 305 



soluble, 315 

 Nitrogen, 43, 93 



cycle of, 316 



related to soil, 304 

 Nodules, 304 



related to plants, 305 

 Noise, 378 

 Nutrients, classification of, 94 



function of, 94 



test for, 95, 96 



Oil fields, 177 

 Opaque, 240 

 Oxidation, 47 



relation to oxygen, 46 

 Oxygen, 93, 145 



relation to air, 42 



Pasteur, Louis, 126 

 Pasteurization, 126 



pasteurizing apparatus, 125 

 Peristalsis, 103 

 Pests, 329 



damage done by, 131 



life history of the fly, 133 



relation to home, 141, 142, 143 

 Phonograph, 380 

 Photography, 396 

 Picture, enlarging, 401 



making, 400 



printing of, 400 

 Pinhole camera, 397 

 Plant enemies, 327 

 Planting, 293 



city gardening, 293 



crop rotation, 305 



for pleasure, 293 



for profit, 293 



relation to soil, 303 



seed table for home gardening, 311 



Plants, changed into living material, 306 



friends, 328, 329 



pests, 314, 317 



relation to soil, 303, 305 



root-hairs, 304 



starch-making power, 306 



test for food, 305 

 Plate culture, 67 

 Pneumatic tank system, 82, 83 

 Polyps, 70 



Preservatives, in relation to foods, 121 

 Prism, 257 

 Projects, list of, 20 

 Prolegs, relation to butterfly, 320 

 Protein, 94 



food rich in, 95 

 Pumps, force, 82 



lift, 81 

 Pupa, 320 

 Pupil, 258 

 Puzzles, 383 



Radiation, 185 

 Rain water, 76 

 Rats, 140 



relation to man, 140 

 Reading, good, 381 

 Recreation, indoor, 372 



outdoor, 294, 391 



relation to home life, 372 

 Reflection, 240 

 Refrigerator, 122 



construction of, 123 



iceless, 124 



use of, 123 



value of, 122 



Resistance in wire to electricity, 363 

 Respiration, artificial, 71 



of cells, 62 



organs of, 69 



products of, 63 



relations to activity, 62 

 Retina, 258 

 Rooms, bedroom, 278 



dining room, 279 



living room, 279 

 Ross, 14 



Sal ammoniac, 361 

 Sanitation, bathroom, 148 



flush tank, 148 



garbage pails, 153 



