Even after four blows, the chain shows not even a nick or dent. The prisoner sighs and falls back against the stone pillar he is chained to.
The room seems to extend in all directions, only separated by massive stone pillars holding up the vaulted ceiling and short pieces of wall separating smaller, but still open chambers from the main room.
However, Morgan soon discovers a trapdoor in the ceiling, an extremely heavy-looking slate of granite, the hinges not visible from this side, only distinguishable from the rest of the ceiling by the faint, rectangular outline.