It was undoubtedly the tall, dark man whom I had addressed in the street. I saw him once more at London Bridge, and then I lost him in the crowd. But I am convinced that he was following me.”

“No doubt! No doubt!” said Holmes. “A tall, dark, heavily moustached man, you say, with gray-tinted sun-glasses?”

“Holmes, you are a wizard. I did not say so, but he had gray-tinted sun-glasses.”

“And a Masonic tie-pin?”

“Holmes!”

“Quite simple, my dear Watson. But let us get down to what is practical. I must admit to you that the case, which seemed to me to be so absurdly simple as to be hardly worth my notice, is rapidly assuming a very different aspect. It is true that though in your mission you have missed everything of importance, yet even those things which have obtruded themselves upon your notice give rise to serious thought.”

“What have I missed?”

“Don't be hurt, my dear fellow. You know that I am quite impersonal. No one else would have done better. Some possibly not so well. But clearly you have missed some vital points. What is the opinion of the neighbours about this man Amberley and his wife? That surely is of importance. What of Dr. Ernest? Was he the gay Lothario one would expect? With your natural advantages, Watson, every lady is your helper and accomplice. What about the girl at the post-office, or the wife of the greengrocer? I can picture you whispering soft nothings with the young lady at the Blue Anchor, and receiving hard somethings in exchange. All this you have left undone.”

“It can still be done.”

“It has been done. Thanks to the telephone and the help of the Yard, I can usually get my essentials without leaving this room. As a matter of fact, my information confirms the man's story. He has the local repute of being a miser as well as a harsh and exacting husband. That he had a large sum of money in that strong-room of his is certain. So also is it that young Dr. Ernest, an unmarried man, played chess with Amberley, and probably played the fool with his wife. All this seems plain sailing, and one would think that there was no more to be said—and yet!—and yet!”

“Where lies the difficulty?”

“In my imagination, perhaps. Well, leave it there, Watson. Let us escape from this weary workaday world by the side door of music. Carina sings to-night at the Albert Hall, and we still have time to dress, dine, and enjoy.”

In the morning I was up betimes, but some toast crumbs and two empty egg-shells told me that my companion was earlier still. I found a scribbled note upon the table.

Dear Watson:

There are one or two points of contact which I should wish to establish with Mr. Josiah Amberley. When I have done so we can dismiss the case—or not.