CONTENTS XXI 



524. Dielectric constant of liquids : Temperature formula 445 



525. " liquefied gases 445 



526. " , standard solutions for measuring; 446 



527. " " of solids 446 



528. " " " crystals 44/ 



529. Electro-striction (means) 448 



530. Piezo-electricity 448 



531. Calculation of the high-frequency resistance of conductors .... 449 



532. Resistance ratio "' F " for isolated round wires 450 



533. " for isolated tubular conductors 450 



534. Coefficients in formula for proximity factor, parallel round 

 wires 450 



535. Ratio of alternating to direct current resistances for copper wires . 451 



536. Max. diam. of wires for high-frequency resistance ratio of 1.01 . . 451 



Wireless Telegraphy 



537. Radiation resistances for various wave lengths and antenna heights. 452 



452 

 453 

 454 

 454 

 455 

 455 



549 

 55o 



55i 

 552 

 553 

 554 

 555 

 556 

 557 

 558 



559 

 560 



538. The dielectric properties of nonconductors 



539. Power factor, insulating materials at radio-frequencies . . 



540. Dielectric constant, insulating materials at radio-frequencies 



541. Absorption factors for radio propagation 



542. Transmission path over sea water, conductivity 1.1 x io -11 e.m.u 



543. " land, conductivity 1.1 x io~ 13 e.m.u. 



544. " " " " " io- 13 e.m.u., €=15 e.s.u. 455 

 545- " " " ground, " io" 15 e.m.u., " " 455 



546. Kilocycle-meter conversion table, 299820 km/sec 456 



547. Wave length, frequency, oscillation constant, 300000 km/sec. . . . 460 



548. Skip-distance and range table 462 



Magnetic Properties 



Definitions and general discussion 463 



Magnetic properties of various types of iron and steel 464 



" a specimen of very pure iron (.017% C) . 464 



" electrical sheets 464 



" two types of American magnet steel . . . 465 



" " a ferro-cobalt alloy, Fe 2 Co (35% cobalt) . 465 



" ring sample of transformer steel, weak fields. 465 



" iron in very weak fields 465 



Composition and magnetic properties of iron and steel 466 



Permeability of some of the specimens in Table 557 468 



Magnetic properties of soft iron at 0° and 100 C 468 



" steel at o° and ioo° C 468 



