Accentuation and vowel/diphthong changes in verbs ending in -λω (examples: βέλω, ἐθέλω, θέλω), discussion of prosodic behavior, contraction before vowels, and examples showing barytone vs disyllabic forms.
παρ´ ἐνίοις δὲ βαρύνεται. τὸ δὲ ἕλω δασυνόμενον ὑποτακτικόν ἐστι τοῦ εἷλον. τὸ δὲ τελῶ ἔχει τὸ τέλος ὄνομα. τὸ μέντοι βέλω ἀπὸ μέσου ἀρχόμενον, ὅθεν βέλος βέλεμος καὶ πλεονασμῷ τοῦ 'ν' βέλεμνον, οὐκ ἔστιν ἐν χρήσει. Τὰ εἰς 'λω' ἔχοντα τὴν πρὸ τέλους συλλαβὴν εἰς φωνῆεν ἢ φωνήεντα λήγουσαν περισπᾶται, ὑπεσταλμένων τῶν ἐχόντων τὴν 'ου' δίφθογγον ἢ τὸ 'ε' ἐν δισυλλάβῳ, καλῶ, χαλῶ, ζηλῶ, δηλῶ, αὐλῶ, πολῶ τὸ ἀναστρέφομαι, πωλῶ, ἀπειλῶ, βουκολῶ, ἀμελῶ, ὠφελῶ. σεσημείωται τὸ ἐθέλω καὶ ὀφείλω. * Τὰ διὰ τοῦ 'λω' ὑπὲρ δύο συλλαβὰς τῷ 'ε' παραληγόμενα, μὴ ἔχοντα ἕτερον 'λ' προηγούμενον περισπᾶται οἷον ὠφελῶ, ἀμελῶ. τὸ δὲ ἐθέλω βαρύνεται. παράλογον οὖν τὸ ἐθέλω κατὰ τόνον τρισύλλαβον ὄν. τὸ δὲ θέλω δισύλλαβον κατὰ τοῦτο ἀναλογώτερόν ἐστι. ἔχομεν γάρ τινα δισύλλαβα βαρυνόμενα, μέλω, ἕλω, κέλω. μηδεὶς δὲ οἰέσθω, ὅτι τὸ ἐθέλω ἐκ τοῦ θέλω ἐστὶ κατὰ πλεονασμὸν τοῦ 'ε'. τὸ γὰρ 'ε' ἐπὶ φωνήεντι πέφυκε πλεονάζεσθαι ὡς τὸ εἶπας ἔειπας, ἐπὶ συμφώνου δὲ οὐ πλεονάζεται. τὸ δὲ θέλω δοκεῖ ἐκ τοῦ ἐθέλω εἶναι· τὸ γὰρ 'ε' τὸ μετὰ συμφώνου ὑπάρχον πέφυκε πολλάκις ἀποβάλλεσθαι, ὡς τὸ ἔφη φῆ, ἔβη βῆ. καὶ δεῖ γινώσκειν, ὅτι ἀεὶ τὸ τρισύλλαβον εὑρίσκεται παρὰ τῷ ποιητῇ ἐθέλω. ἀμέλει ἐν τῷ μήτε σὺ Πηλείδη θέλ´ ἐριζέμεναι (Α 277) δηλονότι κράσει ἐγένετο τοῦ 'η' καὶ 'ε' εἰς 'η'. —πρόσκειται «μὴ ἔχοντα ἕτερον 'λ' προηγούμενον» διὰ τὸ ἀνατέλλω. Τὰ εἰς 'λω' μετ´ ἐπιπλοκῆς συμφώνου περισπᾶται· εἰ δέ τι βεβαρυτόνηται, τοῦτο πάθος ἔχει ἐξ ἐντελεστέρου τοῦ εἰς 'λω' καθαρεύοντος, ἁπλῶ, διπλῶ, τριπλῶ, πιμπλῶ, κυκλῶ, ἀντλῶ. ταῦτα καὶ τὰ ὅμοια περισπῶνται. τὸ μέντοι ὄφλω βαρύνεται ἐκ τοῦ ὀφείλω, ὥσπερ καὶ τὸ κέλω κέκλω καὶ μέλω μέμβλω.
But among some it is given a grave accent. ἕλω, when aspirated, is the subjunctive of εἷλον. τελῶ has as its noun τέλος. βέλω, however, beginning from the middle—whence βέλος, βέλεμος, and with the addition of ν, βέλεμνον—is not in use.
Forms in -λω whose penult ends in a vowel or vowels are circumflexed, except those that have the diphthong ου or have ε in a disyllable: καλῶ, χαλῶ, ζηλῶ, δηλῶ, αὐλῶ, πολῶ ‘I turn back’, πωλῶ, ἀπειλῶ, βουκολῶ, ἀμελῶ, ὠφελῶ. Marked as exceptional are ἐθέλω and ὀφείλω.
Forms in -λω of more than two syllables, with ε in the penult, and not having another λ preceding, are circumflexed, e.g. ὠφελῶ, ἀμελῶ; but ἐθέλω is given a grave accent. Therefore ἐθέλω is anomalous in accent, though it is trisyllabic; θέλω, being disyllabic, is in this respect more regular. For we have certain disyllables that are given a grave accent: μέλω, ἕλω, κέλω.
But let no one suppose that ἐθέλω comes from θέλω by addition of ε. For ε is naturally added before a vowel, as εἶπας, ἔειπας, but before a consonant it is not added. Rather θέλω seems to come from ἐθέλω; for ε after a consonant is naturally often dropped, as ἔφη, φῆ; ἔβη, βῆ. And one must know that the poet always has the trisyllabic form ἐθέλω. At any rate in μήτε σὺ Πηλείδη θέλ´ ἐριζέμεναι (Α 277) it clearly arose by crasis of η and ε into η.
The clause “not having another λ preceding” is added because of ἀνατέλλω.
Forms in -λω with a consonant cluster are circumflexed; and if any has been given a grave accent, it has this as an affection derived from a fuller form in -λω without a cluster: ἁπλῶ, διπλῶ, τριπλῶ, πιμπλῶ, κυκλῶ, ἀντλῶ. These and the like are circumflexed. ὄφλω, however, is given a grave accent from ὀφείλω, just as κέλω becomes κέκλω and μέλω becomes μέμβλω.