672 



Index 



track recorder, automatic, 605, 

 (604) 



tractor, 265 



trade winds, 133, 643, (133) 



transformation of energy, 17-19, 



67-68, 74-75, 82, 83-84, 88, 136, 



170, 222-226, 231, 234, 242, 252- 



253, 260, 330 

 transformer, 225, 234, 235-237, 643, 



(225, 234, 235) 

 translucent, 181, 643 

 transmission, automobile, 265 

 transmitter, 221, 643, (221) 

 transparent, 181, 643 

 transpiration, 496, 501, 523, 643 

 transplanting trees, 524 

 transportation, 



in air, 278-289, 547, 570, 580-582, 



591-593, 603, 605, (281, 282, 283, 



285, 286, 581, 606) 

 on land, 18, 255-269, 547, 605, 



607, (17, 259, 260, 267, 607) 

 on water, 49, 270-277, 286-289, 



547_548, 602-603, 605, 607-608, 



(271, 272, 274, 275) 

 trap, sewer, 60-61, 643, (60) 

 travel, means of, 18, 255-256, 258- 



267, 270-289, 546-548, 570, 580- 



582, 591-593, 602-603, 605, 607- 



608 

 trees, 514-526, (490, 515, 517, 522, 



530, 532) 



enemies of, 516-518 

 planting of, 524 

 protection of, 521 

 value of, 514-516, 518 

 triceps, 330-331, 643, (330) 

 trichinae, 370 

 triplane, 282, 643 

 trolley car, 18, 226, 266 

 Tropic, 



of Cancer, 132, 156, 643, (120) 

 of Capricorn, 132, 643, (120) 

 tropical belts, 132-133, 134 

 truss bridge, 258, 643, (258) 

 trypsin, 403, 405, 643 

 tsetse fly, 454, 643 

 tuberculosis, 347, 448, 454-455, 458- 



459, 470, 471, 472, 544, 643, 



(460, 467) 

 tuning, 643 

 fork, 173, 643 



tuning Cont'd 



musical instruments, 173 



radio, 236, 237-238 

 turbine, 644, (73, 74) 



steam, 273 



water, 51, 72-75, 224 

 tympanic membrane, 176, 644 

 typhoid fever, 54, 58-59, 359, 360, 

 394, 395, 448, 454, 457, 459, 466, 

 468, 544, 644, (460) 

 typhoid fly, 59, 459, 543-544, (459) 

 typhoon, 136, 644 



U 



ultra-violet rays, 582, 644 

 umbra, 183, 644, (183) 

 undershot wheel, 72-73, 644, (73) 

 unit, 



electrical, 211-212 



of structure and function, 315, 

 324, 325, 492 



power, 75, 212, 243 

 United States, 



Department of Agriculture, 141, 

 519, 539 



Forest Service, 520-521 



Post Office Department, 281-282 



Reclamation Service, 76 



Weather Bureau, 121, 126, 135, 



141, 142-143, 145, 645 

 universe, 148, 644 

 Uranus, 150, (149) 

 urea, 416, 417, 425-426 

 Ursa Major, 161, 163, (163) 

 Ursa Minor, 162, 163, (163) 



vaccination, 456, 644 



vaccine, 475, 552, 644 



vacuole, 319-320, 322, 644, (321) 



vacuum, 114-115, 232, 264, 573, 607, 



644 



bottle, 114-115, 644, (115) 

 cleaner, 41, 463 

 system, 113, 644 

 tube, 233, 235-237, 574, 587, 589, 



644, (234, 235} 

 valves, 644 



of heart, 419, 420 

 of machines, 52, 260-262, 264, 276, 

 279 



