[478] Experimental Researches in Chemistry and Physics, p. 372. Philosophical Magazine, 3rd Series, May 1846, vol. xxviii. p. 350.

[479] See also Nature, September 18, 1873; vol. viii. p. 398.

[480] Theory of Political Economy, pp. 3–14.

[481] Principia, bk. i. Prop. iv.

[482] Opticks, bk. i. part ii. Prop. 3. 3rd ed. p. 115.

[483] Experimental Inquiry into the Nature of Heat. Preface, p. xv.

[484] Bence Jones, Life of Faraday, vol. i. p. 362.

[485] Ibid. vol. ii. p. 199.

[486] See also his more formal statement in the Experimental Researches in Electricity, 24th Series, § 2702, vol. iii. p. 161.

[487] Printed in Modern Culture, edited by Youmans, p. 219.