The Swallow's Song
Odysseus' Bow
At a spine-tingling moment in Homer’s Odyssey, when Odysseus is about to reveal who he is to the suitors - whom he will then kill, all 108 of them, with his mighty bow and arrows - Homer creates a marvellous simile in which he compares the stringing of the bow to that by a minstrel of his lyre:
Just as an expert player on the lyre, a seasoned minstrel, pulls around the peg a sheep's-gut cord, and twists and makes it fast, so did Odysseus string the mighty bow with practised ease. He held it in one hand, his right, and with the other plucked the string: It rang out sweetly, like a swallow's call....
ὡς ὅτ᾿ ἀνὴρ φόρμιγγος ἐπιστάμενος καὶ ἀοιδῆς ῥηιδίως ἐτάνυσσε νέῳ περὶ κόλλοπι χορδήν, ἅψας ἀμφοτέρωθεν ἐυστρεφὲς ἔντερον οἰός, ὣς ἄρ᾿ ἄτερ σπουδῆς τάνυσεν μέγα τόξον Ὀδυσσεύς. δεξιτερῇ ἄρα χειρὶ λαβὼν πειρήσατο νευρῆς· ἡ δ᾿ ὑπὸ καλὸν ἄεισε, χελιδόνι εἰκέλη αὐδήν.
(Odyssey 21.406-11)
What is the sound of a swallow’s call? In fact, the bird’s cry is high-pitched and not particularly musical. But Homer is not just describing a sound, he is evoking a world of feeling.
The swallow’s call rings out sweet, because when it is heard it signals that the bird has returned from distant shores after a long and hazardous journey. The hearers of Homer’s song understand its significance: Odysseus, on the point of revealing his true identity after his prolonged and perilous travels, is finally home and dry.
Now at last, as he handles with familiar ease the bow that is about to bring terrible destruction to the suitors, the hero is poised to reclaim his rightful kingship on Ithaca. The soft twang of the bowstring signals - for hero, minstrel, and hearer - the start of the newest, and final, chapter of his odyssey.
Thank you for drawing our ears to the sound, not only of the Greek but to the quivering bow. Swallows haven't returned to the UK yet, but I had them nesting outside my bedroom as a kid and to my ear their vocabulary contains a sound very similar to a bow's quiver. Listen to the unpitched rapid clicking in the first second of this video: https://youtu.be/b_sj1VI6avM?si=qQyKRSltx8ODs6cE That rapid quivering with diminuendo is not the sound of crickets, it is produced by the swallows. When a bow is strung at high tension, the sound it makes when you let fly an arrow has a similar frequency of flutter and duration. I would not describe this quivering sound as "sweet"! Maybe "fine, admirable"? Beauteous because such a sound is associated with an arrow flying straight and far.
As you say, a Swallow does not make a musical sound so I wonder if this is a memory jog to an earlier myth. Does this evoke the thought of Procne who, by using a disguise, wreaks terrible revenge on Tereus for his treatment of her sister Philomela. It would also give an indication to the audience the ferocity and scale of the action about to take place.