[83] “Philosophical Magazine,” section 4, vol. xiii., p. 413, 1857.

[84] “Philosophical Magazine,” section 4, vol. xiv., p. 1, et seq., July, 1857.

[85] “Comptes Rendus” for August, 1853. Also “Philosophical Magazine,” section 4, vol. vii., p. 186, 1854.

[86] “Philosophical Magazine,” section 4, vol. viii., p. 74, 1854.

[87] “Proceedings of the Royal Institution,” January 15, 1875.

[88] “Researches in Chemistry and Physics,” p. 484.

[89] “Connaissance des Temps,” 1825, p. 370.

[90] See Chapter VII., [Part II.]

[91] The effect of the air of London is sometimes strikingly evident.

[92] “Philosophical Transactions,” 1874, Part I., p. 208, and Chapter VII. of this volume.