about three o'clock
He seemed to blame himself for some omission in his investigation the previous afternoon . `` How did it happen ? '' I asked , rather excitedly . `` It was about three o'clock , the guards tell me . The man inside was dozing in a chair before the living-room fireplace . He was placed so he could command a view of the doorway to the library as well as the stairs and reception hall . All at once he was awakened by a shot and a cry from outside .