“There was just one flaw,” interrupted the stranger, ignoring the physician’s question. “The murderer used a sealed envelope. Perhaps he thought it would be more impressive for the code to be found sealed.
“He did not realize the weakness of the situation; neither, for that matter, did the inspector or the detective who investigated the case.”
“The murderer,” murmured Doctor Lukens. “Who can he be?”
“Some one who knew Henry Marchand well!” declared the stranger in an ominous tone. “I do not think the man knew what he was stealing. I believe he surprised Marchand one time when the old man was opening the secret drawer.
“Henry Marchand feared a burglary because his very life depended upon whatever be had hidden. He came here immediately when he learned that some one had entered the house. He came back — to die.”
Doctor Lukens opened the drawer in the center of the desk and produced the thimble. He handed it to the man in black, who examined it. The stranger replaced the thimble in the drawer and saw the pair of dice lying there.
He took them out. They showed the number seven. He dropped them on the table; again they registered seven.
“Loaded,” said the stranger. “That’s curious. Always seven. Did you ever connect the number seven with Henry Marchand?”
“It seems to me I did,” said Lukens thoughtfully. “But I can’t recall the circumstances. Do you see any significance in the number seven?”
“Yes. It may lead us to the murderer.”