“I am not surprised,” said Clarendon, “because it has been puzzling to me. Yet I am beginning to form a theory. I take it that you have no theory of your own.”
Burke shook his head.
“You must be right about that forgery, Mr. Clarendon,” he said. “But as far as I can see, it leaves us nowhere. What does it prove?”
“It proves,” said Clarendon quietly, “that something has been learned by rejecting the obvious.
“We have taken the last step in the dramatic murder of Seth Wilkinson— namely, the finding of a promissory note signed by Horace Chatham — and have rejected its accepted significance.
“Now let us go backward, step by step. What happened before that?”
“Chatham was seen leaving Wilkinson’s apartment.”
“By whom?”
“By attendants at the Grampian Apartments. By Wilkinson’s man.”
“Correct. How well did they know Horace Chatham?”