TABLES 430, 431. 

 DIELECTRIC STRENGTH. 



TABLE 430. Dielectric Strength of Materials. 

 Potential necessary for puncture expressed in kilovolts per centimeter thickness of the dielectric. 



TABLE 431. Potentials in Volts to Produce a Spark In Kerosene. 



Determinations of the dielectric strength of the same substance by different observers do not agree well For a dis- 

 cussion of the sources of error see Mos'cicki, Electrotechn. Z. 25, 1904. 



For more detailed information on the dependence of the sparking distance in oils as a function of the nature of the 

 electrodes, see Edmondson, Phys. Review 6, p. 65, 1898. 



SMITHSONIAN TABLES. 



