This is what I read: First tenant, Mr.Hugh Dennison and family.
Night 1: Heard and saw nothing.
Night 2: The entire household wakened by a scream seemingly coming from below.

This was twice repeated before Mr.Dennison could reach the hall; the last time in far distant and smothered tones.

Investigation revealed nothing.

No person and no trace of any persons, save themselves, could be found anywhere in the house.

Uncomfortable feelings, but no alarm as yet.
Night 3: No screams, but a sound of groaning in the library.
The tall clock standing near the drawing-room door stopped at twelve, and a door was found open which Mr.Dennison is sure he shut tight on retiring.