[2.5.6]The sixth labour he enjoined on him was to chase away the Stymphalian birds. Now at the city of Stymphalus in Arcadia was the lake called Stymphalian, embosomed in a deep wood. To it countless birds had flocked for refuge, fearing to be preyed upon by the wolves. So when Hercules was at a loss how to drive the birds from the wood, Athena gave him brazen castanets, which she had received from Hephaestus. By clashing these on a certain mountain that overhung the lake, he scared the birds. They could not abide the sound, but fluttered up in a fright, and in that way Hercules shot them.

SOURCE: Loeb Apollodorus, translated by Sir James G. Frazer, 1921.