INDEX 



Relay, 323 

 Runners, 212 



School hygiene, 426 

 Shade trees, 47-48 

 Shrubs, 163, 238 

 Smallpox, 372 

 Soaps, 115 

 Solar system, 515 

 Sounder, 322 

 Spectroscope, 518 

 Springs, 48 

 Stains, 116 

 Stars, 530 

 Steamboat, 286 

 Steam engine, 255 

 Steam heating, 9 

 Stereopticon, 453 

 Storing vegetables, 196 

 Stove, 4 



Strawberries, 206 

 Submarines, 294 

 Suet box, 236 

 Swarming of bees, 221 



Talking movies, 456 

 Tank, Hot-water, 56 

 Tea, 95 

 Teeth, 93, 435 

 Telegraph, 318 

 Telephone, 333 

 Telescope, 529 

 Temperature, 22 



Thermometer, 23, 510 

 Thinning, 189 

 Toaster, 149 

 Tools for garden, 187 

 Transplanting, 191 

 Traps, Fly, 413 

 Trick pictures, 454 

 Tuberculosis, 384, 409 

 Turbine, Steam, 288 

 Typhoid fever, 379, 408 



Vaccination, 372, 383 

 Vacuum cleaner, 150 

 Vegetables, 64 

 Ventilation, 19, 28, 427 

 Vines, 166 

 Violin, 123 



Water supply, 45, 347 

 Watt, 246 

 Weather map, 504 

 Weeds, 193 

 Wells, 45, 48 

 Windmill, 54 

 Window box, 138 

 Winter birds, 235 

 Wintering bees, 224 

 Wireless telegraph, 326 

 Wireless telephone, 341 



Yeast, 99 

 Yellow fever, 397 



Zeppelin, 304 



Printed in the United States of America. 



