[515] πέτρη τε. The construction is loose. The literal rendering is ‘there is a rock and a confluence of two roaring rivers.’ This probably means that the Cocytus and Pyriphlegethon run at a higher level than the Acheron, and that just at the place where their two currents join, there is a ledge of rock over which their united waters plunge into the Acheron.
ἐριδούπων seems to point to the noise of a cataract, and the πέτρη may possibly be a mass of rock just parting the falls of the two rivers. In the second “νέκυια” ( Od.24. 11 foll.) Hermes is represented as conducting the souls of the slain suitors to the meadow of asphodel; their path lying “παρ᾽ Ὠκεανοῦ τε ῥοὰς καὶ Λευκάδα πέτρην”, “ἠδὲ παρ᾽ Ἠελίοιο πύλας καὶ δῆμον Ὀνείρων”“ἤισαν”. It is possible that “Λευκὰς πέτρη” contains an allusion to the rock mentioned here, and it may have been so called from being ‘white’ amid the constant foam, or wet and glistening in the spray. For a description of the Styx see on Od. 5.185. It is not easy to understand how the Cocytus is a ‘branch’ of the Styx. In Il.2. 751 foll. the river Titaresios is called “Στυγὸς ἀπορρώξ”, and is said to fall into the Peneus, but not to mix with its waters, “ἀλλά τέ μιν καθύπερθεν ἐπιρρέει ἠύτ᾽ ἔλαιον”.
