For the simple reason that he is confident he has put you off the scent, was my companion's reply. "He is doing the one foolish thing the criminal always does sooner or later; that is to say, he is becoming over-confident of his own powers to elude us. You and I, my friend, should be able to remember several such instances. Now, strange to say, I came across a curious one the other day. Would you care to hear it?"