Discussion of when Greek η and ε take rough (dasy) or smooth (psil) breathing in various morphological and phonological contexts, with examples from Homer and other authors.
ἔνατος ὁμοίως δὲ καὶ τὸ 'η', χωρὶς τῶν συνδέσμων καὶ εἰ μὴ ἐκ κλίσεως εἴη οἷον «ἤνις ἠκέστας» (Il. Ζ 94). τὸ ἡνία, ἐπειδὴ παρὰ τὸν ἥσω μέλλοντα γίνεται, ὁμοίως τῷ ποιήσαντι ἐδασύνθη. πρόσκειται χωρὶς τῶν συνδέσμων διὰ τὸ ἕνεκα καὶ εἵνεκα, ταῦτα γὰρ δασύνονται, καὶ χωρὶς εἰ μὴ ἐκ κλίσεως εἴη διὰ τὴν ἕντος μετοχήν. αὕτη γὰρ δασύνεται. * Τὸ 'ε' πρὸ τοῦ 'ξ', ὑποστελλομένων τῶν παρὰ τὴν ἐξ πρόθεσιν, θέλει δασύνεσθαι, ἕξις, ἑξῆς, ἕξω. οὕτως καὶ τὸ Ἐξάδιος (Α 264) πρὸς τὸν χαρακτῆρα ἐχρῆν δασύνεσθαι, χωρὶς εἰ μὴ λέγοι τις διὰ τὴν ἰδιότητα τὸ πνεῦμα μεταπεπτωκέναι. Τὸ 'η' ἐν τροχαϊκῇ λέξει, ἀμεταβόλου ἐπαγομένου, ψιλοῦται, πλὴν τῶν παρὰ τοῦ ἥσω μέλλοντος, ἦμαρ Σοφοκλῆς (Ai. 475) Τί γὰρ παρ´ ἦμαρ ἡμέρα τέρπειν ἔχει, προσθεῖσα κἀναθεῖσα τοῦγε κατθανεῖν; ἦμος, ἦνις, ἦρα. τὸ ἧλος παρὰ τὸ ἵημι καὶ ἥσω. * Ἀεὶ τὸ 'η' πρὸ φωνήεντος ψιλοῦται, ἠώς, ἤϊα. ταύτῃ καὶ τὸ «ἥ τε ξείνων Θέμις ἐστί» (Od. ι 268) δασύνεται, τὸ δὲ ἠΰτε ψιλοῦται, καὶ τὸ ἕως δασύνεται, τὸ δὲ ἠώς ψιλοῦται, καὶ τὸ ἥλιος δασύνεται, τὸ δὲ ἠέλιος ἐψιλώθη· ὥστε τὸ «ἤϊε Φοῖβε» (Ο 365) εἴτε ἐκ τοῦ ἥϊος δασυνομένου ἐστίν—ἀπὸ τῆς ἕσεως τῶν βελῶν, ὡς Ἀρίσταρχος— εἴτε ἐκ τοῦ ψιλουμένου—ἀπὸ τῆς ἰάσεως, ὡς οἱ περὶ τὸν Κράτητα —πρὸς τὸν χαρακτῆρα μόνως ψιλωτέον. * Τὸ 'η' πρὸ δασέος ψιλοῦται, ἦθος. τὸ δὲ ἡθμός δασύνεται τῇ ἐννοίᾳ τοῦ ἥσω μέλλοντος δασυνομένου. καὶ τὸ Ἥφαιστος δασύνεται διὰ τὴν ἐτυμολογίαν. παρὰ γὰρ τὸ ἅπτω ἐγένετο.
Ninth likewise is also the letter ‘η’, apart from conjunctions and unless it be from inflection, as for example «ἤνις ἠκέστας» (Il. Ζ 94). ἡνία, since it is formed from the future ἥσω, was aspirated in the same way as the word that produced it. The clause “apart from conjunctions” is added because of ἕνεκα and εἵνεκα; for these are aspirated; and “and unless it be from inflection” because of the participle ἕντος, for this is aspirated.
The letter ‘ε’ before ‘ξ’, with the exception of those derived from the preposition ἐξ, wants to be aspirated: ἕξις, ἑξῆς, ἕξω. Thus also Ἐξάδιος (Α 264) ought, in accordance with the written form, to be aspirated, unless someone should say that, because of its peculiarity, the breathing has shifted.
The letter ‘η’ in a trochaic word, when an indeclinable is appended, is written with smooth breathing, except for those derived from the future ἥσω: ἦμαρ—Sophocles (Ai. 475): Τί γὰρ παρ´ ἦμαρ ἡμέρα τέρπειν ἔχει, προσθεῖσα κἀναθεῖσα τοῦγε κατθανεῖν;—ἦμος, ἦνις, ἦρα. ἧλος is from ἵημι and ἥσω.
The letter ‘η’ before a vowel is always written with smooth breathing: ἠώς, ἤϊα. In this way also «ἥ τε ξείνων Θέμις ἐστί» (Od. ι 268) is aspirated, but ἠΰτε is written with smooth breathing; and ἕως is aspirated, but ἠώς is written with smooth breathing; and ἥλιος is aspirated, but ἠέλιος has been written with smooth breathing. Hence «ἤϊε Φοῖβε» (Ο 365), whether it is from ἥϊος with aspiration—“from the sending of arrows,” as Aristarchus says—or from the form with smooth breathing—“from healing,” as those around Crates say—must, as far as the written form is concerned, be written only with smooth breathing.
The letter ‘η’ before an aspirate is written with smooth breathing: ἦθος. But ἡθμός is aspirated by reference to the future ἥσω, which is aspirated. And Ἥφαιστος is aspirated because of its etymology; for it arose from ἅπτω.