First when he stubbles in a dark prison, If the fall into the pit didn't kill him, the rats, cold and wet down there would have eventually led him to a nasty death. His captors, once they realize the pit won't work because it has been discovered, move on the plan B: the pendulum of death. They tie him to a board and slowly lower a swinging pendulum with a scythe, or long, curved blade, attached at the end. Thwarted twice, the captors then set fire to his chamber; he describes, in a rather confusing scene, how he imagines the walls glowing red, and almost melting. He realizes that he will suffocate and burn to death--he is starting to panic.