“‘Let me take your hat,’ I said, little thinking that my courtesy would reveal the true state of affairs. The mere mention of the word hat brought about a terrible change in my visitor; his knees trembled, his face grew ghastly, and he clutched the brim of his beaver until it cracked. He then nervously removed it, and I noticed a dull red mark running about his forehead, just as there would be on the forehead of a man whose hat fitted too tightly; and that mark, gentlemen, had the undulating outline of nothing more nor less than a tiara, and on the apex of the uttermost extremity was a deep indentation about the size of a shilling, that could have been made only by some adamantine substance! The mystery was solved! The robber of the Duchess of Brokedale stood before me.” A suppressed murmur of excitement went through the assembled spirits, and even Messrs. Hawkshaw and Le Coq were silent in the presence of such genius. “My plan of action was immediately formulated. The man was completely at my mercy. He had stolen the tiara, and had it concealed in the lining of his hat. I rose and locked the door. My visitor sank with a groan into my chair. “‘Why did you do that?’ he stammered, as I turned the key in the lock. “‘To keep my Scotch whiskey from evaporating,’ I said, dryly. ‘Now, my lord,’ I added, ‘it will pay your Grace to let me have your hat. I know who you are. You are the Duke of Brokedale. The Duchess of Brokedale has lost a valuable tiara of diamonds, and you have not lost your watch. Somebody has stolen the diamonds, and it may be that somewhere there is a Bunker who has lost such a watch as I have described. The queer part of it all is,’ I continued, handing him the decanter, and taking a couple of loaded six-shooters out of my escritoire—‘the queer part of it all is that I have the watch and you have the tiara. We’ll swap the swag. Hand over the bauble, please.’ “‘But—’ he began. “‘We won’t have any butting, your Grace,’ said I. ‘I’ll give you the watch, and you needn’t mind the £200; and you must give me the tiara, or I’ll accompany you forthwith to the police, and have a search made of your hat. It won’t pay you to defy me. Give it up.’ “He gave up the hat at once, and, as I suspected, there lay the tiara, snugly stowed away behind the head-band. “‘You are a great fellow,’ said I, as I held the tiara up to the light and watched with pleasure the flashing brilliance of its gems. “‘I beg you’ll not expose me,’ he moaned. ‘I was driven to it by necessity.’