"The meaning of what?"
The lawyer took a pack of cards from a drawer and selected a card, which he handed to Dr. Daincourt.
"The Nine of Hearts," said the doctor.
"The card," said the lawyer, "that was found in the pocket of Layton's ulster."
"Is this your tangible link?" asked Dr. Daincourt, turning the card over in his hand.
"It is my tangible link," replied the lawyer.
Dr. Daincourt shrugged his shoulders. "You are adding mystery to mystery."
"I think not," said the lawyer. "You were not in the court when the Nine of Hearts was produced."
"No."
"That and the latch-key of Layton's street door were the only articles found in the pockets of the ulster. When the evidence relating to these articles was being given, I closely observed Layton's face. I knew, but he did not, that these two articles were all that were discovered in the pockets of the incriminating coat. When the latch-key was held up he smiled faintly; he was not surprised. But when the Nine of Hearts was produced there flashed into his eyes a startled look--a look of bewilderment and astonishment; indeed, there was something of horror in his face. I needed no further sign to make me positive that he had no previous knowledge of the card, and that it was the first time he had seen it."