446 



INDEX 



Vacuum, 212 

 Vaporization, 134 

 Veins, 317, 326 

 Ventilation, 147, 149 

 Venus, 2, 3 

 Vertebrates, 358 

 Vibrations, of sound, 212 



of light, 220 

 Vinegar, 273 

 Vitamines, 394 

 Vitreous humor, 237 

 Voice, 216 

 Volatile liquids, 106 

 Volta, 200 

 Voltaic cells, 200 

 Volume, 34 



Water, 93, 290, 299, 395, 416 



electrolysis of, 93 



freezing of, 98 



uses of, 108, 120 



pressure, 110 



city supply, 112, 120, 123 



gravitational, 290 



ground water, 299 



and food, 395 



danger from, 416 

 Water power, 66, 68 



Waterspout, 170 

 Watt, James, 44 

 Waves, sound, 212-213 



light, 220, 232 

 Weather, 152 



weather bureau, 183 

 Weathering, 283, 285 



erosion, 304 

 Weapons, 374 

 Wedge, 54, 62 

 Weeds, 341 

 Weight, 38 

 Wheat rust, 342 

 Wheel and axle, 54, 59 

 Windlass, 60 

 Winds, 163, 164, 171 

 Wood, 259, 260 



uses of, 337 

 Work, 37, 53, 54 

 Worms, 353 



Yard, 30 

 Yeast, 269 



plants, 331, 349 

 Yellow fever, 430 



Zenith, 20 



18 



