"Knowles," said the Duke, in a voice which actually trembled, "Knowles, hoax or no hoax, I will be even with the gentleman who wrote that." Handing the sheet of paper to Mr. Knowles, his Grace turned his attention to the envelope which had been enclosed. It was a small square envelope, of the finest quality, and it reeked with perfume. The Duke's countenance assumed an added frown--he had no fondness for envelopes which were scented. In the centre of the envelope were the words "To the Duke of Datchet," written in the big, bold, sprawling hand which he knew so well. "Mabel's writing," he said to himself, as, with shaking fingers, he tore the envelope open. The sheet of paper which he took out was almost as stiff as cardboard. It, too, emitted what his Grace deemed the nauseous odours of the perfumer's shop. On it was written this letter: "My dear Hereward,--For Heaven's sake do what these people require! I don't know what has happened or where I am, but I am nearly distracted! They have already cut off some of my hair, and they tell me that, if you don't let them have five hundred pounds in gold by half-past five, they will cut off my little finger too. I would sooner die than lose my little finger--and--I don't know what else besides. "By the token which I send you, and which has never, until now, been off my breast, I conjure you to help me.--MABEL. "Hereward--_help me!_" When he read that letter the Duke turned white--very white, as white as the paper on which it was written. He passed the epistle on to Knowles. "I suppose that also is a hoax?" He spoke in a tone of voice which was unpleasantly cold--a coldness which Mr. Knowles was aware, from not inconsiderable experience, betokened that the Duke was white-hot within. Mr. Knowles's demeanour, however, betrayed no sign that he was aware of anything of the kind, he being conscious that there is a certain sort of knowledge which is apt, at times, to be dangerous to its possessor. He read the letter from beginning to end. "This certainly does resemble her Grace's writing." "You think it does resemble it, do you? You think that there is a certain faint and distant similarity?" The Duke asked these questions quietly--too quietly. Then, all at once, he thundered--which Mr. Knowles was quite prepared for--"Why, you idiot, don't you know it is her writing?" Mr. Knowles gave way another point. He was, constitutionally, too much of a diplomatist to concede more than a point at a time. "So far as appearances go, I am bound to admit that I think it possible that it is her Grace's writing." Then the Duke let fly at him--at this perfectly innocent man. But, of course, Mr. Knowles was long since inured.