[29] Proceedings, IX (1897), 244.

[30] Phil. Mag., XXIX (1890; 5th series), 56.

[31] Ibid., p. 292; Nature, XXXVI, 412.

[32] Proc. Camb. Phil. Soc., IX (1897), 333.

[33] Ibid., p. 345.

[34] Phil. Mag., XLVI (1898), 528.

[35] Verh. der deutsch. phys. Ges., XVI (1914), 422.

[36] Phil. Mag., V (1903; 6th series), 354.

[37] Op. cit., p. 429.

[38] Phys. Rev., XXVI (1908), 198.