“Certainly it is.”

“Then I am hanged if I see how you are going to do it. Not, I should say, by offering a group of vague coincidences that would muddle any brain but your own.”

Thorndyke chuckled softly but pursued the subject no farther.

“Put that paper in your file with your other notes,” he said, “and think it over at your leisure. And now I want a little help from you. Have you a good memory for faces?”

“Fairly good, I think. Why?”

“Because I have a photograph of a man whom I think you may have met. Just look at it and tell me if you remember the face.”

He drew a cabinet size photograph from an envelope that had come by the morning’s post and handed it to me.