332 TABLES 4O5, 405A 



TABLE 405. Variation of Electrical Kesistance of Glass and Porcelain with Temperature. 



The following table gives the values of a, b, and c in the equation 



log R = a + bt + cfl, 



where R is the specific resistance expressed in ohms, that is, the resistance in ohms per centimeter of a rod ona 

 square centimeter in cross section.* 



* T. Gray, " Phil. Mag." 1880, and " Proc. Roy. Soc." 1882. 

 TABLE 405a.- Temperature Resistance Coefficients of Glass, Porcelain and Quartz dr/dt. 



Somerville, Physical Review, 31, p. 261, 1910. 



SMITHSONIAN TABLES. 



