4io 



INDEX 



Calorie, 99 



Camera, 255, 397 



Candle, relation to air, 44 



Canning foods, 124 



Capillaries, 146 



Capillarity, experiment in, gravel, sand, 



clay, and loam, 300 

 Carbohydrates, 94 



test for, 95 



Carbon, 93, 176, 179, 361 

 Carbon dioxide, 43 



fire extinguisher, 215 

 Carbon tetrachloride extinguishers, rela- 

 tion to fire, 213 

 Carelessness, 31 

 Carpet beetles, 139 



destruction of, 139 

 Caterpillar, 320 

 Caves, formation of, 86 

 Cellar, 282 



relation to heat, 282 

 Cells, 48 



electric, dry, 361 

 joining of, 365 

 life of, 366 

 to make, 362 

 wet, 361 



in body, 47 



respiration, 62 



Centrifugal force, demonstration of, 395 

 Cesspool, 153 

 Chemical elements, 93 

 Chemical extinguishers, types, 213 



section of, 215 

 Choroid, 258 

 Chrysalis, 320 

 Ciliary, 259 



Cinders, removal of, 265 

 Cisterns, 77 

 Cleanliness, habits of, 169 



relation to clothes, 232 



relation to home life, 31 

 Clothing, 220 



attacked by insect, 139 



care of, 232 



frauds in, 231 



origin of, 225 



relation to cold, 220 



use of, 223 



Coal beds in the earth, 176 

 Coal stove, 190 

 Cockroaches, 138 



Cocoon, 320 



Cold, relation to clothing, 220 



Cold frame, 309 



Cold storage warehouse, 121 



Color, 256 



in the home, 276 



nature of, 256 

 Color blindness, 264 

 Combustion, 46 



Commercial motors, in the home, 35 2 

 Concrete skyscraper, 272 

 Conduction, 186 

 Convection currents, 184, 185 



caused by hot stove, 191 

 Cooking, methods of, in, 112 



relation to food, 109 



use of heat in, 198 

 Cootie, 139 

 Corn smut, 317 

 Cotton, description of, 227 



relation to body, 227 

 Cotton plant, 227 

 Crop rotation, reasons for, 305 

 Crowding, menace to health, 30 

 Culex, 135 

 Culture medium, 67 

 Current, electric, 348 



sources of, 351 

 Currents, convection, 185, 190, 191, 192 



direction of air, 65 



electric wire resistance, 363 



Decay, 119, 165 



cause of, 119 



of teeth, 165 

 Diaphragm, 60 



D ets, differences in, reasons for, 104 

 Digestion, 99, 100 

 Digestive tract, 100 



nature of, 101 

 Diseases, body defenses against, 163 



of air passages, 70 

 Disinfectants, use of, 162 

 Drainage system, relation to water sup- 

 ply, 79 



pipes, 151 



relation to home, 28, 50 

 Drinking cup, hygienic, 167 

 Drugs, abuse of, 171 



use of, 170 

 Dust, danger of, 66 



proper removal of, 68 



