[248] Greenwich Observations for 1866, p. xlix.
[249] Philosophical Transactions, 1856, p. 309.
[250] Penny Cyclopædia, art. Transit, vol. xxv. pp. 129, 130.
[251] Ibid. art. Observation, p. 390.
[252] Nature, vol. i. p. 85.
[253] Nature, vol. i. p 337. See references to the Memoirs describing the method.
[254] Principia, Book I. Law III. Corollary VI. Scholium. Motte’s translation, vol. i. p. 33.
[255] Graham’s Chemical Reports and Memoirs, Cavendish Society, pp. 247, 268, &c.
[256] Regnault’s Cours Elémentaire de Chimie, 1851, vol i. p. 141.
[257] Tyndall’s Faraday, pp. 114, 115.