Mrs. Hall almost fainted after seeing something in the stranger's room.

From the text:

As she did so, a most extraordinary thing happened. The bed-clothes gathered themselves together, leapt up suddenly into a sort of peak, and then jumped headlong over the bottom rail. It was exactly as if a hand had clutched them in the centre and flung them aside. Immediately after, the stranger's hat hopped off the bed-post, described a whirling flight in the air through the better part of a circle, and then dashed straight at Mrs. Hall's face. Then as swiftly came the sponge from the washstand; and then the chair, flinging the stranger's coat and trousers carelessly aside, and laughing drily in a voice singularly like the stranger's, turned itself up with its four legs at Mrs. Hall, seemed to take aim at her for a moment, and charged at her. She screamed and turned, and then the chair legs came gently but firmly against her back and impelled her and Hall out of the room. The door slammed violently and was locked. The chair and bed seemed to be executing a dance of triumph for a moment, and then abruptly everything was still.