80.  Child, Phys. Rev. Vol. 12, 1901.

81.  Rutherford, Phil. Mag. p. 210, August, 1901; Phys. Rev. Vol. 13, 1901.

82.  Rutherford, Phil. Mag. Aug. 1901.

83.  A simple and excellent account of the effects produced by the motion of a charged ion and also of the electronic theory of matter was given by Sir Oliver Lodge in 1903 in a paper entitled “Electrons” (Proceedings of the Institution of Electrical Engineers, Part 159, Vol. 32, 1903). See also J. J. Thomson’s Electricity and Matter (Scribner, New York, 1904).

84.  J. J. Thomson, Phil. Mag. April, 1887.

85.  Heaviside, Collected Papers, Vol. II. p. 514.

86.  Searle, Phil. Mag. Oct. 1897.

87.  Abraham, Phys. Zeit. 4, No. 1 b, p. 57, 1902.

88.  A full account of the path described by a moving ion under various conditions is given by J. J. Thomson, Conduction of Electricity in Gases (Camb. Univ. Press, 1903), pp. 79–90.

89.  J. J. Thomson, Phil. Mag. p. 293, 1897.

90.  Lenard, Annal. d. Phys. 64, p. 279, 1898.

91.  Kaufmann, Annal. d. Phys. 61, p. 544; 62, p. 596, 1897; 65, p. 431, 1898.

92.  Simon, Annal. d. Phys. 69, p. 589, 1899.

93.  A complete discussion of the various methods employed to measure the velocity and mass of electrons and also of the theory on which they are based will be found in J. J. Thomson’s Conduction of Electricity through Gases.