Tables 51 3 and 51 4 

 DIELECTRIC STRENGTH 



439 



TABLE 513. — Steady Potential Difference in Volts required to produce a Spark in Air with 



Ball Electrodes 



Based on the results of Bailie, Bichat-Blondot, Freyburg, Liebig, Macfarlane, Orgler, Paschen, Quincke, de la Rue, 

 Wolff. For spark lengihs from i to 200 wave-lengths of sodium light, see Earhart, Phys. Rev. 15, p. 163; Hobbs, 

 Phil. Mag. 10, p. 607, 1905. 



TABLE 514. — Alternating Current Potential required to produce a Spark in Air with various 



Ball Electrodes 



The potentials given are the maxima of the alternating waves used. Frequency, ^ cycles per 



second. 



Based upon the results of Kawalski, Phil. Mag. 18, p. 699, 1909. 



Smithsonian Tables. 



