It was witnessed by Mildred Green, who described herself as a cook, and by Arthur Green, whose description of his profession was valet. Their addresses were Mayfield.
“I think those are the two servants the old man discharged for pilfering some six months ago. The will must have been executed a few weeks before they left.”
Tab’s first feeling was one of pleasure that at last his friend was a rich man. Poor Rex, little did he dream that he would come into his inheritance in so tragic a fashion.
Carver put the document back into the box and continued the examination of the door which Tab had interrupted.
“It isn’t a spring lock, you notice,” he said. “So, therefore, it couldn’t have been slammed by a murderer who first shot Trasmere and then made his escape. It has to be locked either from the inside or the outside. If there was any reasonable possibility of Trasmere having shot himself, the solution would have been simple. But he did not shoot himself. He was shot here, the door was locked upon him and the key returned to the table—how?” He took the key and tried one of the air-holes of the ventilator. The point of the key scarcely entered. “There must be some other entrance to the vault,” he said.
The sun was up before they finished their examination of the room. The walls were solid. There was neither window nor fireplace. The floor was even more substantial than the walls.
In a last hopeless endeavor to solve the mystery, Carver called in an expert to inspect the ventilator. It was made of steel, a quarter of an inch thick, and fastened into the door itself. There were no screws with which it could have been taken out and even if it had been removed, only the tiniest of mortals could have crept through.
“Still,” said Carver, “if we could suppose that the ventilator was removable, we might have taken a leaf from Edgar Allen Poe and thought seriously of a trained monkey being introduced.”
“There is the theory of the duplicate key—”
“Which I dismiss,” said Carver. “I am satisfied that no duplicate key was used. If a duplicate key had been procurable, Felling or Walters as you call him, would have found his way to it. He is the cleverest man in that business and he has lived on duplicate keys all his life. He must have known that it was impossible to gain admission by such a method or he wouldn’t have taken the trouble to make one. He is a specialist in that line of business, probably the finest locksmith of the underworld.”