Socrates: Take, for instance, Διὶ φίλος; to change this from a phrase to a name, we took out the second iota and pronounced the middle syllable with the grave instead of the acute accent (Diphilus). ― translation from: Harold N. Fowler, Plato in Twelve Volumes, volume XII (1921), “Cratylus”, 399b
Tone is the resonance of a voice endowed with harmony. It is heightened in the acute, balanced in the grave, and broken in the circumflex. ― translation from: Thomas Davidson, The Grammar of Dionysios Thrax (1874), § iii: “On Tone”, page 4
Be silent! Silent! Let the sandal’s tread // Be light, no jarring sound. // Depart ye hence afar, and from his bed withdraw. // In these lines the words σῖγα σῖγα λευκόν are sung on one note; and yet each of the three words has both low and high pitch. And the word ἀρβύλης has its third syllable sung in the same pitch as its middle syllable, although it is impossible for a single word to carry two acute accents. ― translation from: Stephen Usher, opere citatoLCL 466 (1985), chapter xi, paragraph 4, page 81, lines 5–13
ante AD 210, Sextus Empiricus (author), August Immanuel Bekker (editor), Πρὸς Μαθηματικούς in Sextus Empiricus ex recensione Immanuelis Bekkeri (1842), book I (Α′), § 113 (page 624, lines 13–18):