"Yes. Tall, dark, beard and whiskers. Might have been false. When you were in the house he passed the door, looked at the number and walked away." "And you let him go?" I said reproachfully. "I didn't think that of you." "You needn't. I followed him on your account." "Bravo!" "Had to be very careful. His eyes were in all directions." "Did he go back to Soho?" "No. He took a 'bus to Piccadilly Circus. I took the same 'bus. He got down there, with a lot of others, and I slipped out among them. Then he took an Atlas 'bus to the Eyre Arms. So did I. He walked towards the Swiss Cottage, and my difficulties commenced. Not much foot traffic between the Eyre Arms and the Swiss Cottage, you know. He went on to Fitzjohn's Parade. More traffic there. The job got easier. Beyond Fitzjohn's Parade, very little traffic indeed. I had to be more careful than ever, so few people about. That was the end of it." "You know the house he went into?" I cried. "I don't," he answered. "I am ashamed to say he gave me the slip. I don't know whether he suspected he was being followed, but the fact remains that he gave me the slip. How he managed it beats me. I am fairly ashamed of myself." "You ought to be. Wheeler, you were on the track of a great mystery," and just at the very point---- I was so annoyed that I couldn't finish the sentence. "I remained in the neighborhood a couple of hours," he continued, "but saw nothing more of the gentleman. If I had suspected there was anything important hanging to it he would have had to be a great deal smarter than he is to throw me off the track. However, it's no use crying over spilt milk. I've nothing to do this week. Can I be of any help to you?" "I think so," I replied. "Come and see me at eight o'clock in the morning, and I'll tell you all about it. I must have time to think this out. Though you were not entirely successful you have done me a great service, and I am obliged to you. Oh, Wheeler, if you had only seen the house he went into!" He shook his head mournfully, and left me, promising to call in the morning. I had, indeed, plenty to think about. It was in Finchley Road that Jack fancied he saw the ghost of Louis. This man, following me from Madame Lourbet's shop, where he had been hidden from my gaze by a green curtain, had made his way to Finchley, where, presumably, he lived. I might now almost call the case upon which I was engaged The Mystery of the Green Curtain. CHAPTER XXXII.