Crookes tube
When Dr. Whipple naps, he tosses and turns and starts babbling in French until he suddenly awakes. He tells the narrator that he had strange visions of lying in an open pit, inside a house with constantly shifting features, while faces stared down at him. Many of the faces were those of the Harris family, whose members died in the house. When the narrator sleeps, he is awakened by a horrific scream. He sees a revolting yellowish "corpse-light" bubbling up from the floor, which stares at him with many eyes before vanishing in a wisp through the chimney. He finds his uncle transformed into a monster with "blackened, decaying features" and dripping claws. He turns on the Crookes tube, but seeing that it has no effect, escapes the house through the cellar door as his uncle's body dissolves, transforming into a multitude of faces of those who died in the house as it melts. The narrator returns the next day to find his equipment intact, but no body.