452 



INDEX. 



PAGE 



Weston normal cell xli 



Weston portable cell xlili 



Wiedemaiui magnetic effect 365 



Wind pressures 150-153 



Wire gages, comparison 333 



Wire, mechanical properties: copper 82-83 



steel 78 



sifi'l rope and cable . 79 



Wire resistance, auxiliary table for computing . . . 322 



Wire tables: aluminum, English measures .... 342 



metric measures .... 343 



see also 334 



copper, English measures 336 



metric measures 339 



see also 334 



temperature coefficients .334,335 

 reduc. to std. . .335 



Wires, alternating-current resistance 344 



carrying capacity of 329 



high-frequency resistance 344 



V.ires. .beat losses from incandescent, bright Pt. . 255 

 Pt sponge . 255 



Wireless telegraphy: antennae resistances .... 364 

 wave-lengths, frequencies, oscil- 

 lation constants 362 



Wolf sun-spot numbers, 1750 to 1917 415 



Woods: densities 96-99, 112 



mechanical properties: conifers, Eng. units. 99 



metric units 97 



hard wds, Eng. units 98 



metric units 96 



Work, conversion factors , , 197 



PAGE 



X-rays: 383-393 



absorption coefficients (mass) 389 



atomic numbers and spectra . . " . . 390-393 



calcite grating space 408 



cathode efficiencies 387 



characteristic radiations 387 



corpuscular radiation 387-388 



crystals, diffraction with 401 



energy relations 387 



general radiations 387 



heterogeneous radiations 387 



homogeneous radiations 387 



independent radiations 387 



intensity 388 



ionization 388 



K series of radiations 390 



L series of radiations 391 



M series of radiations 392 



monochromatic radiations 387 



secondary radiations 387 



spectra: absorption 393 



K series 390 



L series 391 



M series 392 



tungsten 392 



wave-lengths 390-393 



wave-lengths and cathode fall 387 



Years 414, 437 



\ early temperature means 420 



Young's modulus, definition 74 



values 74-103 



Yield point (mechanical property) 74-103 



Zero, absolute, thermodynamic scale 195 



Zonal harmonics 64. 



