[368] First Principles, 3rd edit. chap. x. p. 253.

[369] Laplace, System of the World, vol. i. pp. 50, 54, &c.

[370] Herschel’s Outlines of Astronomy, 4th edit. pp. 555–557.

[371] Humboldt’s Cosmos (Bohn), vol. iii. p. 229.

[372] Encyclopædia Metropolitana, art. Sound, § 323; Outlines of Astronomy, 4th edit., § 650. pp. 410, 487–88; Meteorology, Encyclopædia Britannica, Reprint, p. 197.

[373] Philosophical Transactions, (1739), vol. xli. p. 126.

[374] Principia, bk. iii. Prop. 15.

[375] Lockyer’s Lessons in Elementary Astronomy, p. 301.

[376] Treatise on Natural Philosophy, vol. i. pp. 337, &c.

[377] An Introduction to Natural Philosophy, 3rd edit. 1733, p. 5.