eight o'clock on Christmas Eve
Berwin -- so called -- was dead , his assassin had melted into thin air , and the Silent House had added a second legend to its already uncanny reputation . Formerly it had been simply haunted , now it was also blood-stained , and its last condition was worse than its first . The dead man had been found stabbed to the heart by some long , thin , sharp-pointed instrument which the murderer had taken away with him -- or perhaps her , as the sex of the assassin , for obvious reasons , could not be decided . Mrs. Kebby swore that she had left the deceased sitting over the fire at eight o'clock on Christmas Eve , and that he had then been fairly well , though far from enjoying the best of health . When she returned , shortly after nine , on Christmas morning , the man was dead and cold . Medical aid was called in at the same time as the police were summoned ; and the evidence of the doctor who examined the body went to prove that Berwin had been dead at least ten hours ; therefore , he must have been assassinated between the hours of eleven and twelve of the previous night . Search was immediately made for the murderer , but no trace could be found of him , nor could it be ascertained how he had entered the house .