Groping about the masonry just below the margin, I succeeded in dislodging a small fragment, and let it fall into the abyss. For nearly a minute I hearkened to its reverberations as it dashed against the sides of the chasm in its descent; at length there was a sullen plunge into water, succeeded by loud echoes.

This quotation appears when the narrator nearly stumbles into the pit in the pitch blackness. He uses the small stone to gauge how deep it goes. The reverberations, splash, and echoes convey the terrifying depth of the pit. This description makes it clear that the monks intended the narrator to stumble into the pit in the dark. In addition, it plays with our understanding of the room, which seemed to be a normal stone dungeon. Both the narrator and the reader are left disoriented and newly alert to the dangers of the pit.

In one of its panels a very singular figure riveted my whole attention. It was the painted figure of Time as he is commonly represented, save that, in lieu of a scythe, he held what, at a casual glance, I supposed to be the pictured image of a huge pendulum, such as we see on antique clocks.

This description appears as the narrator awakens to find himself bound by straps. Here he notices the pendulum for the first time, although he does not yet understand its significance. The pendulum appears to spring from one of the painted ceiling panels, integrated into an image of Father Time, an allegorical figure of mortality often depicted with an hourglass and a scythe. However, instead of a painted scythe the narrator discerns the real blade of the pendulum. The pendulum’s almost seamless integration with the prison art suggests a unity of purpose to the decor. Everything in this dungeon is designed to kill.

Demon eyes, of a wild and ghastly vivacity, glared upon me in a thousand directions where none had been visible before, and gleamed with the lurid lustre of a fire that I could not force my diseased imagination to regard as unreal.

This description of the false iron walls of the prison appears after the narrator evades the pendulum. In retaliation, the monks begin to heat the walls, preparing to force him into the pit. The glowing “demon eyes” of the figures painted on the walls and the fire-like luster that covers the walls signifies that the walls are burning hot. They also metaphorically suggest the rising anger of the monks over the narrator’s escape, and the rising danger that comes with their fury.

Could I resist its glow? or, if even that, could I withstand its pressure? And now, flatter and flatter grew the lozenge, with a rapidity that left me no time for contemplation. Its centre, and, of course, its greatest width, came just over the yawning gulf.

Here, the narrator describes the horrific situation he finds himself in as the monks move the heated walls closer together, threatening to sear his flesh with hot metal unless he flings himself into the pit. As hinted at previously, everything in the prison is under the control of the monks and can be changed according to their whims. In addition, every element is dangerous and potentially deadly. Not even the walls or ground have any safety and stability.