They both turned quickly towards him. The Inspector smiled in a confidential manner at Laura. It was obvious that he knew what was coming.

“Some years ago,” the Professor continued, “I bought this house and made a present of it to—”

“To whom?” Quest asked quickly.

“To my servant Craig,” the Professor admitted with a groan.

Lenora gave a little cry. She turned triumphantly towards the Inspector.

“All recollection as to its locality had escaped me,” the Professor continued sorrowfully. “I remember that it was on the anniversary of his having been with me for some fifteen years that I decided to show him some substantial mark of my appreciation. I knew that he was looking for a domicile for his father and mother, who are since both dead, and I requested a house agent to send me in a list of suitable residences. This, alas! was the one I purchased.”

Quest glanced around the place.

“I think,” he said, “that the Professor’s statement now removes any doubt as to Craig’s guilt. You are sure the house has been closely watched, Inspector?”

“Since I received certain information,” French replied, “I have had half-a-dozen of my best men in the vicinity. I can assure you that no one has entered or left it during the last twenty-four hours.”

They made their way to the piazza steps and entered by the front door. The house was an ordinary framework one of moderate size, in poor repair, and showing signs of great neglect. The rooms were barely furnished, and their first cursory search revealed no traces of habitation. There was still the broken skylight in the room which Lenora had occupied, and the bed upon which she had slept was still crumpled. French, who had been tapping the walls downstairs, called to them. They trooped down into the hall. The Inspector was standing before what appeared to be an ordinary panel.