INDEX 



487 





Gasoline, preparation of, 124-125 



to remove grease, 146 



to remove paint, 147 

 Gastric juice, 93-94 

 Geese, 464, 465 

 Gelatin, 84 



Geographic environment, 393-396 

 Geysers, 415-416 

 Gills, 469-470 

 Glass, 256-257 



molding, 46 

 Glucose, 97-98 

 Gold, 179 

 Granite, 417-418 

 Graphite, 120, 216 

 Gravity water system, 334 

 Great Salt Lake, 189 

 Guitar, 284 

 Gully, 363 



Hard water, 144-145 

 Headache, caused by eyestrain, 260- 

 261 



remedies, 194-195 

 Heat, and chemical change, 32, 66 



and light, 269-270 



and temperature, 33 



and vegetation, 270 



effect upon food, 32, 82-90 



evaporation, 41 



given out by cooling, 34-35 



given out by dissolving, 49 



given out by melting, 44-45 



needed to produce steam, 38 



non-conductors of, 29-30 



produced by electricity, 210-213 



produced by food, 68, 71 



produced by friction, 52 



sources of, 36 



specific, 34-35 



unit of, 33 



See Boiling; Condensation; Con- 

 duction ; Convection 

 Heating, central plant, 23 



fireplace, 21, 22 



Heating, furnace, 22-23 



hot-water, 23-27 



steam, 39 

 Helix, 217 

 Horn, 287 



Horse, 309, 462, 463 

 Horse power, 307-309 

 Hot springs, 415-416 

 Hot-water heating, 23-27 

 Humidity, 42, 44 

 Hurricanes, 404 

 Hybrid, 428 



Hydrochloric acid, for carbon dioxide, 

 60 



for chlorine, 159 



for glucose, 97 



in bleaching, 161 



to test fabrics, 135 

 Hydrogen, 345 

 Hygiene, public, 202-206 

 Hypo, 264 



Ice, 46-47 

 Ice cream, 49, 102 

 Igneous rock, 417-418 

 Illumination, 275-280 



and eyestrain, 247-251 



by electricity, 213, 280 



circle of, 396-398 

 Incandescent mantle, 277-278 

 Inclined plane, 297-300 

 Indigo, 168 



Indirect dyeing, 170-171 

 Infection, 199 

 Ink spots, 163 

 Insects, characteristics of, 477-478 



helpful, 478 



injurious, 476477 

 Instruments, musical, 284-288 

 Insulation, 221 

 Intestine, 95-96 

 Invertebrates, 478 

 Inverted burners, 278 

 Iron, coated with tin, 176-177 



galvanized, 54, 177-178 



