1. For the theoretical explanation of the deviation from this law for strong fields observed by Kapitza (Proc. Roy. Soc., A, 123, 292; 1929) see N. H. Frank, Zeit. f. Physik, 63, 596; 1930.
2. Leipziger Vorträge, 1930, p. 75, see specially p. 85.
3. Zeit. f. Physik, 47, 1; 1928.
4. See Sommerfeld, I.c., equations (77a), (34), (42a), (48c). Our E0 Is Sommerfeld's kT log A, n is the number of electrons per cm.2 of the metal.