The Duke plainly hesitated. He would--and he would not. The stranger, as he eyed him, seemed much amused.

"My dear Duke, by all means act on Mr. Dacre's valuable suggestion. As I said before, why not? It would at least be interesting to see if the Duchess does or does not lose her arm--almost as interesting to you as to Mr. Dacre. Those blackmailing, kidnapping scoundrels do use such empty menaces. Besides, you would have the pleasure of seeing me locked up. My imprisonment for life would recompense you even for the loss of her Grace's arm. And five hundred pounds is such a sum to have to pay--merely for a wife! Why not, therefore, act on Mr. Dacre's suggestion? Here comes the constable." The constable referred to was advancing towards them--he was not a dozen yards away. "Let me beckon to him--I will with pleasure." He took out his watch--a gold chronograph repeater. "There are scarcely ten minutes left during which it will be possible for me to send the communication which I spoke of, so that it may arrive in time. As it will then be too late, and the instruments are already prepared for the little operation which her Grace is eagerly anticipating, it would, perhaps, be as well, after all, that you should give me into charge. You would have saved your five hundred pounds, and you would, at any rate, have something in exchange for her Grace's mutilated limb. Ah, here is the constable! Officer!"

The stranger spoke with such a pleasant little air of easy geniality that it was impossible to tell if he were in jest or earnest. This fact impressed the Duke much more than if he had gone in for a liberal indulgence of the--under the circumstances--orthodox melodramatic scowling. And, indeed, in the face of his own common sense, it impressed Mr. Ivor Dacre too.

This well-bred, well-groomed youth was just the being to realise--aux bouts des ongles--a modern type of the devil, the type which depicts him as a perfect gentleman, who keeps smiling all the time.

The constable whom this audacious rogue had signalled approached the little group. He addressed the stranger:

"Do you want me, sir?"

"No, I do not want you. I think it is the Duke of Datchet."

The constable, who knew the Duke very well by sight, saluted him as he turned to receive instructions.

The Duke looked white, even savage. There was not a pleasant look in his eyes and about his lips. He appeared to be endeavouring to put a great restraint upon himself. There was a momentary silence. Mr. Dacre made a movement as if to interpose. The Duke caught him by the arm.

He spoke: "No, constable, I do not want you. This person is mistaken."