'I am perfectly clear on that point;' and Miss Montressor's vivid memory recalled every particular of the last interview between herself and Mr. Dolby, shaking her head the while with an emphasis confirmatory of her words. 'That is an exceedingly important point,' said Bryan Duval, 'because you see, my dear Clara, it is plain that Mr. Dolby must have known something previously concerning Mr. Foster and the nature and purport of his business in London, otherwise he would not have so regarded the probabilities of their meeting as to make it indispensable that he should keep out of his way when passing as Mr. Dolby; and it is just this presumable knowledge of poor Griswold's business that makes Mr. Dolby of so much importance to us in the unravelling of this story, since we cannot get hold of any one who really does know enough about it to be able to suggest a possible motive for his murder.' 'I quite understand all that,' replied Miss Montressor, 'and I have told you everything that can possibly throw any light upon it. Stay, there's just one thing more. I called at his lodgings in Queen-street, Mayfair, once--only once--it was after the last time I saw him, and I inquired for him by the name of Dunn; but he had left, and gone, the woman of the house thought--believed, I ought to say--to America.' 'You and he had quarrelled, Clara, and you expected to find him there, you sly puss!' 'Perhaps so,' she answered, with a coquettish toss of her head; 'but he didn't show up, you see; and I know nothing more about him.' 'I hope you care as little as you know?' 'You may make your mind quite easy on that score. My heart is not fragile, and when it is broken, it will not be by Mr. Dolby.' 'That's right, Clara, or by "the likes of him," as we make the Irishry say in our Emerald Isle pieces. And now I'm sure you must be awfully tired of all this _interrogatoire_, in which you have acquitted yourself nobly, though your last little bit of information makes it plain that Mr. Dolby, or Mr. Dunn, came out to America before we came, and can therefore throw no light upon the murder of poor Griswold.' 'I don't see that,' said Thornton Carey; 'if we could find him here in New York, he could tell us what he knew of Griswold's secret business in London, and in _that_ lies the germ of the murder.' 'You think so, do you, my young friend? But then you are young, and your knowledge of men and cities is a good deal limited.' This was Bryan Duval's mental comment on Thornton Carey's remarks. His spoken reply was more respectful, though vague. He merely said: 'Of course, of course. But we need not detain Miss Montressor any longer. You have some shopping to do, I know;' and he gallantly conducted the lady to the door, after she had taken leave of Thornton Carey in a most gracious and engaging manner. Then he returned to Thornton, his manner entirely changed, his face lighted with a glow of success, his eyes sparkling, and a hardly subdued excitement all over him.