Bolder, recalled, was disposed to be cheerfully communicable. Certainly he would know the man again; he had a good look at him. The sun was shining brightly, and it had fallen full on the fellow's face. "Describe him, then," said Indiman, note-book in hand. Put to the test, Bolder was not so good a witness as we had hoped for; he wandered and grew confused in his statements. Light hair? Yes, it might have been that--though, now that he thought of it, the shade was rather on the darkish order. An old man? Well, not noticeably so; perhaps thirty-five or a little younger. "Or a little older--say fifty-five?" "Well, it might have been fifty-five, sir. I couldn't swear to it exactly." "That will do, Bolder," said Indiman, and our witness retired abashed. "Check number one," commented Indiman. "Suppose we try the Grand Central now. We won't take out the carriage; the day is fine and I want the walk." It was a beautiful morning in August, cool and clear, and we strode along briskly. A hand-organ began playing in a side street, and we stopped to listen. "It's the same aria," I said, excitedly--"'Celeste Aida.' What tremendous luck! No, it isn't; deuce take it!" I went on, dejectedly. "But you just said it was the same," persisted Indiman. "With a difference," I hastened to explain. Now, Indiman is not musical, and I had some trouble in convincing him that within the compass of a semitone a veritable gulf may yawn. This particular organ played the phrase in the third bar correctly--F sharp and not F natural--and consequently it could not be the same instrument that had vexed my ears half an hour ago at No. 4020 Madison Avenue. "There is a real difference, then?" said Indiman, thoughtfully. "One that you would recognize again?" "At any place or time," I answered, confidently. "It is an absolute means of identification, quite as much so as a glass eye would be in a man's face." "Very good. We'll find that hand-organ, then, if we have to go through 'Little Italy' with a drag-net. How beautifully the problem is working out!--almost too beautifully." At the incoming baggage-room Indiman presented the check numbered 18329. A porter appeared with a large trunk loaded on a truck. "City transfer?" he asked. "No, I'll take it with me," said Indiman. "Thorp, will you get a hack." We were about to drive off, and I felt for my match-box. Provoking! I must have left it at home, and I wanted a cigarette. "One moment," I called, and jumped out, having caught sight of Ellison, who had been with me in college. He was hurrying into the station. I should be glad to have a word with him and secure a match at the same time. But somehow I missed him in making my way through the swinging doors. Ellison was nowhere to be seen, and I had to content myself with getting a light at the cigar counter. I went back to the carriage and climbed in. "It was Ellison," I explained. "A good chap, and I should have liked to meet him."