Table 295. 



285 



VARIATION OF ELECTRICAL RESISTANCE OF CLASS AND PORCELAIN 



WITH TEMPERATURE. 



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



log Ji z= a + it + cfl, 

 where Jt is the specific resistance expressed in ohms, that is, the resistance in ohms per centiffletre of a rod one 

 square centimetre in cross section.* 



Smithsonian Tables. 



* T. Gray, " PhU. Mag." 1880, and " Proc. Roy. Soc." i88a. 



