284 



Tables 293, 294. 



DIELECTRIC CONSTANTS {contmuel). 



TABLE 293. — Dlelectrlo Oonstants of SoUds {continued). 



TABLE 284. — Dielectric Constants of Crystals. 



D a, Dj8, D7 are the dielectric constants along the brachy, macro and vertical axes respectively. 



Substance. 



Uniaxial: 

 Apatite . 

 Beryl . . 



Calcspar . . 



Dolomite . . 

 Iceland spar 

 Quartz . . 



Rutil (TiOa). 

 Tourmaline . 



Zircon . 



Wave- 

 length, 

 cm. 



75 



75 



75 

 75 



1000 

 75 

 75 



00 



75 

 75 



Diel. const. 



Axis. II Axis. 



9-50 

 7-85 

 7.10 

 6.05 



8.49 

 8.78 

 7.80 

 8.50 

 4.69 



4-38 

 4.27 



4-32 

 89 

 7-13 

 6.75 



7.40 



7-44 

 6.05 



5-52 

 7.56 

 8.29 

 6.80 

 8.00 

 5.06 

 4.46 



4-34 

 4.60 



173 

 6.54 

 5-65 

 12.6 



Substance. 



Rhombic : 

 Arragonite 



Barite 



Ccelestin . , 

 Cerussite 

 MgS04-(-7H20 

 K2SO4 . . 

 Rochelle salt 

 Sulphur . . 



Topaz . 



Wave- 

 length, 



75 

 00 



75 

 75 

 75 



75 

 75 



Diel. const. 



Da Dj8 D7 



9.14 

 9.80 

 6.97 



7-65 

 7.70 

 25.4 



5-26 

 6.09 

 6.70 

 3.81 



365 

 3.62 

 6.65 



7.68 

 10.09 

 12.20 

 18.5 



27.2 

 6.05 

 5.08 

 6.92 



3-97 

 3-85 

 3-85 

 6.70 



6-55 

 7.00 

 7.70 

 8.30 

 19.2 

 8.28 

 4-48 

 8.89 



4-77 

 4.66 

 4.66 

 6.30 



•5 ►. 



1 Schmidt, 1903. 



2 Starke, 1897. 



3 Curie, 1889. 



4 Fallinger, 1902. 



5 V. Pirani, 1903. 



6 Ferry, 1897. 



7 Borel, 1893. 



8 Boltzmann, 1875. 



Smithsonian Tables. 



