The Pit and The Pendulum by Edgar Allan Poe

*******For some thirty or sixty minutes, he concentrates on scaring the rats away from his food, but when he again looks at the ceiling, he sees that the arc of the pendulum's swing is about a yard larger, that the pendulum is swinging faster, and that, most importantly, the pendulum has visually descended. The pendulum, he now sees, has a razor-like edge of steel and is attached to the ceiling by a brass rod.

What is the event and the setting in the above?