Puteoli too was still the seaport town of Rome as of all Central Italy, and the Syrians were then the carriers of the Mediterranean trade.[8] That is one reason why Apollo's oracles at Cumae and Hecate's necromatic cave at Lake Avernus still prospered. When Vergil explored that region, as the details of the sixth book show he must have done, he had occasion to learn more than mere geographic details.
[Footnote 8: Frank, An Economic History of Rome, chap. xiv.]
That Vergil had Isaiah, chapter II, before his eyes when he wrote the fourth Eclogue is of course out of the question; there is not a single close parallel of the kind that Vergil usually permits himself to borrow from his sources; we cannot even be sure that he had seen any of the Sibylline oracles, now found in the third book of the collection, which contains so strange a syncretism of Mithraic, Greek, and Jewish conceptions, but we can no longer doubt that he was in a general way well informed and quite thoroughly permeated with such mystical and apocalyptic sentiments as every Gadarene and any Greek from the Orient might well know. It speaks well for his love of Rome that despite these influences it was he who produced the most thoroughly nationalistic epic ever written.
The first fruit of Vergil's studies in evolutionary science at Naples was the Aetna, if indeed the poem be his. The problem of the authorship has been patiently studied, and the arguments for authenticity concisely summarized by Vessereau[9] make a strong case. The evidence is briefly this. Servius attributed the poem to Vergil in his preface and again in his commentary on Aeneid, III, 578. Donatus also seems to have done so, though some of our manuscripts of his Vita contain the phrase de qua ambigitur. Again, the texts of the Aetna which we have agree also in this ascription. Internal evidence proves the poem to be a work of the period between 54 and 44, which admirably suits Vergilian claims. Its close dependence upon Lucretius gives the first date, its mention of the "Medea" of the artist Timomachus as being overseas, a work which was brought to Rome between 46 and 44, gives the second. Finally, the Aetna is by a student of Epicurean philosophy largely influenced by Lucretius. It would be difficult to make a stronger case short of a contemporaneous attribution. Has not Vergil himself referred to the Aetna in the preface of his Ciris, where he thanks the Muses for their aid in an abstruse poem (l. 93)?
Quare quae cantus meditanti mittere caecos[10]
Magna mihi cupido tribuistis praemia divae.
What other poem could he have had in mind? The designation does not fit the Culex, which is the only poem besides the Aetna that could be in question. It is best, therefore, to take the Aetna[11] into account in studying Vergil's life, even though we reserve a place in our memories for that stray phrase de qua ambigitur.
[Footnote 9: Vessereau, Aetna, xx ff.; Rand, Harvard Studies, XXX, 106, 155 ff. It is difficult to avoid the conclusion that Seneca attributed the Aetna to Vergil in ad Lucilium 79, 5: The words "Vergil's complete treatment" can hardly refer to the seven meager lines found in the third book of the Aeneid.]
[Footnote 10: Lucretius is very fond of using the word caecus with reference to abstruse and obscure philosophical and scientific subjects.]
[Footnote 11: When Vergil wrote the Georgics, on a subject which the poet of the Aetna derides as trivial (264-74) he seems to apologize for abandoning science, in favor of a meaner theme, Georgics II, 483 ff. Is not this a reference to the Aetna?]
The poet after an invocation to Apollo justifies himself for rejecting the favorite themes of myth and fiction: the mysteries of nature are more worthy of occupying the efforts of the mind. He has chosen one out of very many that needs explanation. The true cause of volcanic eruption, he says, is that air is driven into the pores of the earth, and when this comes into contact with lava and flint which contain atoms of fire, it creates the explosions that cause such destruction. After a second invitation to the reader to appreciate the worth of such a theme he tells the story of two brothers of Catania who, when other refugees from Aetna's explosion rescued their worldly goods, risked their lives to save their parents.