[10] See f. inst. N. Bohr, Phil. Mag. xxv. p. 24 (1913). The conclusion drawn in the paper cited is strongly supported by the fact that hydrogen, in the experiments on positive rays of Sir J. J. Thomson, is the only element which never occurs with a positive charge corresponding to the loss of more than one electron (comp. Phil. Mag. xxiv. p. 672 (1912)).
[11] F. Paschen, Ann. d. Phys. xxvii. p. 565 (1908).
[12] E. C. Pickering, Astrophys. J. iv. p. 369 (1896); v. p. 92 (1897).
[13] A. Fowler, Month. isot. Kov. Astr. Soc. lxxiii. Dec. 1912.
[14] W. Ritz, Phys. Zeitschr. ix. p. 521 (1908).
[15] J. W. Nicholson, loc. cit. p. 679.
[16] A. Einstein, Ann. d. Phys. xvii, p. 146 (1905).
[17] R. W. Wood, Physical Optics, p. 518 (1911). Phil. Mag. S. 6. Vol. 26. No. 151. July 1913.
[18] Compare J. J. Thomson, Phil. Mag. xxiii. p. 456 (1912).
[19] E. Rutherford, Phil. Mag. xxiv. pp. 453 & 893 (1912).