Forb., improving upon Wagn., seems to have set this passage in its true light. ‘Vix ea fatus erat,’ as he remarks, naturally introduces some unforeseen event (comp. 1. 586., 2. 692., 3. 90), so that its real reference here must be to the portent mentioned v. 523: Virg. however probably thought that the effect of the interposition would be greater if it came when Aeneas was despondent, and so throws in the intervening lines, which leads him to change the construction. ‘Ora tenebant’ 2. 1 note.
 They were brooding sorrowfully over the perilous future, and would have gone on brooding, had not Venus sent a sign. Wagn. comp. 6. 358 “iam tuta tenebam, Ni gens crudelis . . . invasisset.” The imperfect indicative followed by nisi is a favourite construction with Tacitus. “Suo tristi cum corde volutat” 6. 185. Comp. also Enn. A. inc. fr. 24, “Hand temere est quod tu tristi cum corde gubernas.” With ‘putabant’ comp. “multa putans” 6. 332. Serv. has an odd piece of lexicographical explanation: “Unde et arbores putari dicuntur, quia diu deliberatur quid eis adimi debeat, quid relinqui.”
 Caelo from heaven. ‘Aperto’ 1. 155. It was thunder in a cloudless sky that constituted the sign. It is scarcely necessary to refer to Hor. 1 Od. 34. 5 foll. Cerda strangely explains ‘aperto’ “rupto et hiante tonitribus, fulguribus, fragore,” referring to the language in the O. T. about shutting and opening the heaven. Mr. Gladstone (Studies, vol. 3. p. 523) comments severely on this creation of a “Cytherea tonans:” but it is merly an application of the belief that gods had besides their own special functions a general divine power. Not to mention the thunder wielded by Pallas 1. 42, which seems to have been a special privilege we may compare the instances in Hom. where they borrow things from each other, Aphrodite borrowing the car of Ares, Here the cestus of Aphrodite. Besides, we are not told here that Venus sent the the thunder independently of Jupiter, so that we may easily suppose him to have launched it at her request. Here too the thunder and lightning only come in as the physical manifestation of the clashing and the glitter of the divine armour carried through the sky. It may be observed that Venus plays the part of a sender of storms in the second book of Valerius Flaccus.
 “Cum sonitu trahit” 2. 466. “Tremere omnia visa repente” 3. 90. ‘Ruere’ expresses the effect of the crash, ‘fragor:’ everyghing shook as if on the point of falling. “Ruit arduus aether” G. 1. 324 is not the same thing, as the reference there is to a downfall of rain. Lucr. 4.403 has “non supra sese ruere ommia tecta minari.”
 “Cum tuba depresso graviter sub murmure mugit” Lucr. 4.543. The invention of the trumpet was ascribed to the Tyrrhenians (Soph. Aj. 17 &c.); but the epithet here has special force, as it is a Tyrrhene alliance that has been proposed to Aeneas. “Clangor tubarum”2. 313. ‘Tyrrhenus tubae clangor’ like “Nemeaeus hiatus leonis” Lucr. 5.24 &c.
 The thunder is repeated thrice as Gossrau remarks, comp. 7. 141. ‘Intonat,’ the reading before Heins., is found in Serv., but in none of Ribbeck's MSS. IN 12. 332 the MSS. are more divided. Gud. has a variant ‘sonus’ for ‘fragor.’ ‘Increpare’ occurs Cic. de Or. 2. 5 apparently of the hurtling of the discus, and Enn. Thy. fr. 2 has “sed sonitus auris means pedum pulsu increpat.”
 Inter nubem may seem inconsistent with ‘regione serena’ and ‘per sudum:’ but the cloud is evidently not meant to be a rain or thunder cloud (see however on v. 608) and probably only serves to form a sort of medium through which the armour appears, like the mist in which the Homeric gods carry heroes away. Comp. 7. 142, and note there. Virg. was probably thinking of Lucr. 6.99 “Nec fit enim sonitus caeli de parte serena Verum ubicumque magis denso sunt agmine nubes,” where the usual phaenomena of thunder are described. Ribbeck omits ‘in’ from Med. a m. p. and a quotation in Nonius 31. 15: but this hardly seems authority enough.
 Sudum subst.: see Freund. In G. 4. 77 it is an adjective. ‘Vident’ of hearing v. 360. Pal. and Rom. have ‘sonare.’ For the sound of arms in the air as a portent comp. G. 1. 474, where it is one of the phaenomena at the time of Caesar's death.
 Adgnovit sonitum et divae promissa parentis, recognized in the sound the fulfilled promise. Comp. Aesch. Ag. 123 ἐδαη λαγοδαίτας Πομπούς τ᾽ ἀρχάς, Soph. O. T. 1054 νοεῖς ἐκεῖνον ὅντιϝ᾽ ἀρτιως Μολεῖν ἐφιέμεσθα τόν Θ᾽ οὗτος λέγει;
 Memorat: see on 2. 650. ‘Ne vero’ 11. 278, μὴ δῆτα. The earnestness seems partly to arise from Aeneas' elevation of mind, partly intended to allay Evander's fears. ‘Profecto’ is virtually i. q. ‘vero.’
 Ferant seems to combine the notions of announcing and actually bringing. ‘Ego’ emphatic. Serv. speaks of two punctuations, after ‘poscor’ and after ‘Olympo,’ The former has been revived by Peerlkamp, Ladewig, and Haupt: but the rhythm is strongly against it. Aeneas might well say that he was called by Olympus, after the sign of the divine will just given. Comp. “sonitus Olympi” 6. 586. There is a general resemblance between Aeneas' position here with regard to Evander and Oedipus' relation to Theseus when the thunder comes announcing his end. Perhaps we may comp. with this passage Soph. O. C. 1654, where Theseus is described by the messenger after the death of oedipus as γῆν τε προσκυνοῦνθ᾽ ἅμα Καὶ τὸν θεῶν Ὄλυμπον ἐν ταὐτῶ λόγω.
 Germ. comp. Soph. O. C. 94 “σημεῖα δ᾽ ἥξειν τῶνδέ μοι παρηγγύα Ἢ σεισμὸν ἢ σροντήν τιν᾽ ἢ Διὸς σέλας”. This is another instance of Virg.'s fondness for incidental narrative. Hom. makes Thetis promise to Achilles, who is altogether without arms, that she will procure armour from Hephaestus. Venus' good intentions towards Aeneas are more gratuitous, and therefore we only hear of the promise indirectly. “Diva creatrix” 6. 367. For the omission of “se” with ‘missuram’ see Madv. § 401. ‘Canere’ of prophetic utterance 7. 79 &c.
 It is difficult to understand from this cursory notice what were the exact terms of Venus' promise. We do not know the time when the promise was given, and this ignorance must affect our understanding of the condition ‘si bellum ingrueret.’ If we suppose Venus' promise to have been made shortly before Aeneas started for Pallanteum, then ‘si bellum ingrueret’ will be the thing about which Venus was to give a sign, the sound and flash of armour answering the double purpose of indicating that the armour itself was being brought and that war was at hand, for which last object see G. 1. 474, referred to on v. 529. But it seems more natural to believe that the promise was made while war was still a mere contingency, and that Venus undertook in the event of trouble arising in Italy to bring armour from Vulcan, and to make it heard and seen as she brought it. This will account better for Aeneas' exaltation, as his previous depression would then be owing to his seeing a doubtful war before him, without having received the promised sign of divine aid. Gossrau thinks the hemistich shows that Virg. could not work out the passage as he wished, and adds “quod si talibus in locis quasi de opere absoluto iudicas, poetae facis iniuriam.” ‘Volcania arma’ 12. 739.
 Comp. generally Latinus' forebodings 7. 595 foll., and the prophecy of Nereus Hor. 1 Od. 15. 4, which Virg. may have had in his mind.
 For the latter half of this line and for the next comp. 1. 100 note Here Rom. and one of Ribbeck's cursives have ‘unda,’ and one inferior copy ‘undis.’ With the general auticipation comp. 6. 87. Heyne remarks that there is no battle at the Tiber like that at the Scamander: Virg. however has chosen to repeat the image 12. 35.
[541-553] ‘After sacrificing to Hercules, Aeneas sends part of his crew home with news, and prepares to go himself with others on horseback to the Etruscan camp.’