“In other words, this is what you think. The Englishman, desirous of covering up his tracks, conceived the idea of having this imitation on hand, in case it might be of use in the daring and disgraceful undertaking you ascribe to him. Recognizing his own inability to do this himself, he delegated the task to one who in some way, he had been led to think, cherished a secret grudge against its present possessor—a man who had had some opportunity for seeing the stone and studying the setting. The copy thus procured, Mr. Grey went to the ball, and, relying on his own seemingly unassailable position, attacked Mrs. Fairbrother in the alcove and would have carried off the diamond, if he had found it where he had seen it earlier blazing on her breast. But it was not there. The warning received by her—a warning you ascribe to his daughter, a fact which is yet to be proved—had led her to rid herself of the jewel in the way Mr. Durand describes, and he found himself burdened with a dastardly crime and with nothing to show for it. Later, however, to his intense surprise and possible satisfaction, he saw that diamond in my hands, and, recognizing an opportunity, as he thought, of yet securing it, he asked to see it, held it for an instant, and then, making use of an almost incredible expedient for distracting attention, dropped, not the real stone but the false one, retaining the real one in his hand. This, in plain English, as I take it, is your present idea of the situation.” Astonished at the clearness with which he read my mind, I answered: “Yes, Inspector, that is what was in my mind.” “Good! then it is just as well that it is out. Your mind is now free and you can give it entirely to your duties.” Then, as he laid his hand on the door-knob, he added: “In studying so intently your own point of view, you seem to have forgotten that the last thing which Mr. Grey would be likely to do, under those circumstances, would be to call attention to the falsity of the gem upon whose similarity to the real stone he was depending. Not even his confidence in his own position, as an honored and highly-esteemed guest, would lead him to do that.” “Not if he were a well-known connoisseur,” I faltered, “with the pride of one who has handled the best gems? He would know that the deception would be soon discovered and that it would not do for him to fail to recognize it for what it was, when the make-believe was in his hands.”