TABLES 343, 344. 309 



DIELECTRIC CONSTANTS. 



TABLE 343. Dielectric Constant (Specific Inductive Capacity) of Gases. 



Atmospheric Pressure. 

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



TABLE 344. Variation of the Dielectric Constant with the Temperature. 



For variation with the pressure see next table. 



If Z?0 = the dielectric constant at the temperature 8 C., Dt at the tempera- 

 ture t C., and a and )3 are quantities given in the following table, then 



DQ = Dt [i a(t 0) + j8(f 0) a ]. 

 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 fact that D i is approximately pro- 

 portional to the density. 

 SMITHSONIAN TABLES. 



