Passage 8.16.5
Ἑβραίοις δὲ Ἑλένης γυναικὸς ἐπιχωρίας τάφος ἐστὶν ἐν πόλει Σολύμοις, ἣν ἐς ἔδαφος κατέβαλεν ὁ Ῥωμαίων βασιλεύς. μεμηχάνηται δὲ ἐν τῷ τάφῳ τὴν θύραν, ὁμοίως παντὶ οὖσαν τῷ τάφῳ λιθίνην, μὴ πρότερον ἀνοίγεσθαι, πρὶν ἂν ἡμέραν τε ἀεὶ καὶ ὥραν τὸ ἔτος ἐπαγάγῃ τὴν αὐτήν· τότε δὲ ὑπὸ μόνου τοῦ μηχανήματος ἀνοιχθεῖσα καὶ οὐ πολὺ ἐπισχοῦσα συνεκλείσθη διʼ ἑαυτῆς. τοῦτον μὲν δὴ οὕτω, τὸν δὲ ἄλλον χρόνον ἀνοῖξαι πειρώμενος ἀνοίξαις μὲν οὐκ ἄν, κατάξεις δὲ αὐτὴν πρότερον βιαζόμενος.
The Hebrews have a tomb in the city of Jerusalem, their local city, of a woman named Helen, which the Roman emperor razed to the ground. At the tomb there is constructed a door of stone, which, like the rest of the tomb, is devised in such a way that it cannot be opened until a particular day and hour of the year arrives. At that precise moment, it opens of its own accord through the mechanism alone, remains open a brief time, and then closes shut again by itself. Thus does it function; but should a man try to force it open at another time, he would be unable to open it and, indeed, would sooner break it by violence.