Passage 10.19.1
παρὰ δὲ τὸν Γοργίαν ἀνάθημά ἐστιν Ἀμφικτυόνων Σκιωναῖος Σκύλλις, ὃς καταδῦναι καὶ ἐς τὰ βαθύτατα θαλάσσης πάσης ἔχει φήμην· ἐδιδάξατο δὲ καὶ Ὕδναν τὴν θυγατέρα δύεσθαι.
Next to the statue of Gorgias is a dedication by the Amphictyons depicting Scyllis of Scione, who has the reputation of being able to dive into even the greatest depths of any sea. He also taught his daughter Hydna to dive.