Passage 8.34.2
οὐ πόρρω δὲ τοῦ ἱεροῦ γῆς χῶμά ἐστιν οὐ μέγα, ἐπίθημα ἔχον λίθου πεποιημένον δάκτυλον, καὶ δὴ καὶ ὄνομα τῷ χώματί ἐστι Δακτύλου μνῆμα· ἐνταῦθα ἔκφρονα Ὀρέστην γενόμενον λέγουσιν ἕνα τῆς ἑτέρας τῶν χειρῶν ἀποφαγεῖν δάκτυλον. τούτῳ δέ ἐστιν ἕτερον συνεχὲς χωρίον Ἄκη καλούμενον, ὅτι ἐγένετο ἐν αὐτῷ τῆς νόσου τῷ Ὀρέστῃ τὰ ἰάματα· πεποίηται δὲ Εὐμενίσι καὶ αὐτόθι ἱερὸν.
Not far from the temple is a small earthen mound bearing on it a stone carved to resemble a finger; indeed, the mound itself is known as the "Tomb of the Finger." Here, people say, Orestes, being driven mad, bit off one of the fingers of his own hand. Immediately next to this spot is another place called Ake ("Healing"), so named because there Orestes recovered from his illness; and here too a sanctuary has been established for the Eumenides.