System of Logic. Introduction, § 4. Fifth ed. pp. 8, 9.

Ibid. bk. II. chap. iii. § 5, pp. 225, &c.

These are the figurate numbers considered in pages 183, 187, &c.

Bk. ii. chap. iv.

Philosophical Transactions (1866), vol. 146, p. 334.

Budget of Paradoxes, p. 257.

Proceedings of the Royal Society (1872–3), vol. xxi. p. 319.

Life of Galileo, Society for the Diffusion of Useful Knowledge, p. 102.

Professor Bowen has excellently stated this view. Treatise on Logic. Cambridge, U.S.A., 1866, p. 354.

Roscoe’s Spectrum Analysis, 1st edit., p. 98.

Euler’s Letters to a German Princess, translated by Hunter. 2nd ed., vol. ii. pp. 17, 18.

Lavoisier’s Chemistry, translated by Kerr. 3rd ed., pp. 114, 121, 123.

Euler’s Letters, vol. ii. p. 21.

Lardner, Edinburgh Review, July 1834, p. 277.

Mémoires par divers Savans, tom. vi.; quoted by Todhunter in his History of the Theory of Probability, p. 458.