knew him as he left the office that afternoon."

"Undoubtedly he did meet many."

"They didn't come forward to say they had seen him."

"I can see no reason why they should do so. There was no question of
fixing the time he left. I was able to give definite information on
that point."

"Well, we seem to have used up our facts," said Quarles, "and are forced
to theorize."

Delverton smiled.

"You must not jump to the conclusion that I have failed," said the
professor quickly. "I did not promise to tell you the name of the
murderer to-night. Let me theorize for a few moments. You told me you
believed that Farrell's tragic end had hastened your brother's death. Did
your brother chance to come to the office that day?"

"No."

"Perhaps he came that night after you had left. I suppose you cannot
bring evidence that he did not?"

"No; but--"

"Or it might have been with him that Farrell had an appointment that day,
which was connected with some affair you were not intended to know