"What is your little game?" continued the man. "Come, out with it; I am going to know." Al was decidedly embarrassed. "It is all a mistake," he stammered. "That's too thin," said the stranger. "I'm onto you; you are a detective! Now, what are you shadowing me for?" Al could not help laughing. "I am no more a detective than you, sir," he said. "I told my driver to follow a certain carriage, and he has made a mistake; that's all there is to it." "I made no mistake," interposed the driver, surlily. "This is the carriage you told me to follow." "You are wrong; the man in that carriage was not this gentleman. Remember, it turned the corner before we left the depot, so you lost sight of it for half a minute or so." "That's so," admitted cabby. "It had probably turned out of the street before we turned into it, and you, seeing this gentleman's carriage, supposed it to be the same, and followed it." "I guess that explains it." "Well, it doesn't explain it to me," said the aggrieved stranger. "I consider this affair an outrage, and I am going to have it investigated." "Go ahead and investigate, then," said Al, losing his patience. "You are making a mountain of a mole hill." "I am, eh? Well, you'll see whether I am or not. Cabman, I have your number." "That's all right; keep it," growled the jehu. "I shall keep it, and make good use of it, too. You will hear from me again." And the man climbed back into his carriage, flushed almost as much with anger as with wine. CHAPTER XXVIII. AN EXCITING INTERVIEW. As the carriage rolled away Al and the cabman stood and stared at each other. Then the latter burst into a loud laugh. "Well, sir," he said, "this is the funniest job I have had for many a long day." Al failed to appreciate the humor of the situation. "It does not strike me as being particularly funny," he said. "It doesn't?" "Decidedly not. Why did you lose sight of the other cab?" "Why, you explained that yourself just now. The two carriages looked just alike; I believe they were the same." "No, they were not. The man I saw looking from the window of the carriage that passed the Grand Central Depot was not the man we have just been talking to." "Are you sure?" "Yes. You followed the wrong carriage; that is all there is to it." "Well," admitted the cabby, "I think you are right. Where shall I take you now?" "Nowhere; I'll walk. How much do I owe you?" "Ten dollars," was the calm reply. "Ten what?" demanded Al. "Dollars." "Ten dollars for driving me that short distance?" "Do you call that a short distance?" "Yes; I could have walked it in a good deal less than half an hour." "Why didn't you, then?" "I----" "Now, see here," interrupted the cabman, with a threatening air, as he put his face in very close proximity to Al's, "I don't want no muss with you. See? But I get that ten dollars. Do you think I'm driving this here thing for fun? Not on your life!"