TABLES 286, 287. 279 



DIELECTRIC CONSTANTS. 



TABLE 286. -Dielectric Constant (Specif io Inductive Capacity) of Gases. 

 Atmospheric Pressure. 



Wave-lengths of the measuring current greater than 10000 cm. 



TABLE 287. -Variation of the Dielectric Constant with the Temperature. 



For variation with the pressure see next table. 



If >e = the dielectric constant at the temperature 8 C., Dt at the tempera- 

 ture / C., and a and & are quantities given in the following table, then 



& 9 = Dt [i (/ 6) + $(t 6)2]. 

 The temperature coefficients are due to Badeker. 



The dielectric constant of air at atmospheric pressure but with varying tem- 

 perature may also be calculated from the tact that D i is approximately pro- 

 portional to the density. 

 SMITHSONIAN TABLES. 



