The discussion of phenomena in which air plays a part is contained chiefly in Books II. and VI., and here the distinction of terms in English has been, so far as practicable, maintained. In Book II. “air” is a translation of _aër_ about a dozen of times out of a total of over fifty times that “air” occurs, and in Book VI. about half a dozen out of a total of nearly seventy. The following is a list of the places in which “air” translates _aër_:-- Book I. throughout. Book II. pp. 56, ll. 20, 21; 57, ll. 17, 22; 58, l. 3; 59, l. 26; 61, l. 18; 66, l. 12; 71, l. 9; 72, l. 22; 77, 1. 17; 98, l. 26; 101, l. 28. Book III. pp. 120, ll. 8, 9 (four times); 121, ll. 11–20 (five times); 123, l. 28; 129, l. 3; 134, ll. 26, 28; 135, l. 1; 140, l. 29. Book IV. pp. 176, ll. 6, 9; 184, l. 2; 186, l. 16. Book V. pp. 195, l. 32; 196, l. 7; 198, l. 3; 199, l. 16; 202, l. 6; 205, l. 11; 206, l. 3; 211, ll. 14, 20. Book VI. pp. 245, l. 28; 249, l. 10; 251, ll. 8, 9; 259, l. 7; 260, ll. 26, 29. Book VII. throughout, with _three exceptions_, viz. pp. 277, l. 26; 279, l. 16; 281, l. 4. In a few cases “air” occurs as a more explicit representation of a pronoun or an adjective which implies it: in these instances the context is generally a sufficient guide. _Spiritus_, too, has sometimes quite a different rendering, _e.g._ breath. On pp. 111, 139, 152, “air” is used of a very slight breeze, the very gentlest breath of wind, and represents _aura_--a good illustration of the ambiguity of language. QUOTATIONS Seneca is fond of illustrating his subject by passages from the poets. His favourites are Virgil and Ovid, and only once does he quote Lucretius, whose work was much more analogous to his own. The quotations are apparently from memory and betray occasional inaccuracies, as even the best memories will. The following is a list of the references:-- Book I. Pref., 8 (p. 6). Virg. _Aen._ iv. 404. i. 4 (10). Virg. _Aen._ v. 528. iii, 4 (17). Ovid, _Metamorp._ vi. 65. 7. v. 6 (25). Nero in an unknown poem: one or two other tags of that versatile tyrant have been preserved. vi. 1 (28). Virg. _Georg._ i. 380. 1. xi. 2 (35). Virg. _Georg._ ii. 95. 6. xiv. 2 (38). Virg. _Georg._ i. 367. (cf. VII. xx. 1). xvii. 5 (45). Virg. _Eclog._ ii. 25. 6. Book II. i. 2 (51). Ovid, _Metamorp._ i. 55. xliv. 1 (91). Ovid, _Metamorp._ iii. 305–7. Book III. Pref., 3 (109). Origin unknown: a somewhat similar sentiment occurs in _Aetna_, 24. i. 1 (114). Ovid, _Metamorp._ iii. 407. i. 1 (114). Virg. _Aen._ i. 245. 6. i. 1 (114). Lucilius, to whom the _Q.N._ was addressed. If he was the author of _Aetna_, as seems not improbable, he may have written other poems on Sicilian topography. xx. 2 (133). Ovid, _Metamorp._ xv. 313. 4 (cf. _Ibid._ xi. 3 _sqq._). xx. 4 (134). Ovid, _Metamorp._ xv. 321. xx. 5 (134). Ovid, _Metamorp._ xv. 330. 1.