"That is a wild theory," said Mallow. "Let us stick to the facts. Whoever Carson may be, you forget we have yet to prove him an impostor. The one thing we are sure of is that Clara Trall was a spy." "Do you intend questioning Semberry about her?" "No, that would put him on his guard at once. I shall go to Amelia Street, and see this Mrs. Arne." "The same thing applies to her, surely?" "No. I shall merely call on Mrs. Carson's behalf to inform her that Clara left her mistress's service without warning of any kind, and ask her if she can throw any light on her eccentric behaviour. It is quite natural Mrs. Carson should wish to know. I shall thus throw the onus of any explanation on her." "She will only lie to you. She may not even do that,--probably she will express her very great regret, and confess her inability to understand it." "Well, of course, that is probable. I must chance it. She may let fall something of value." Aldean put on his hat and coat. "So you intend to begin with this clue?" he asked dubiously. "Well, I think it is the most likely to bear fruit." "And what about the murder?" asked Aldean. Mallow pointed to a neat pile of newspaper cuttings. "I am refreshing my memory on that point. But, for the present, I think I shall leave it alone. We have not yet anything sufficiently strong to connect Carson with it. That sandal-wood is not enough. I believe in going slowly and relying on facts only." "Well, old man, good-bye and good luck," said Lord Aldean. "See you again soon;" and he took himself off to transact some small business of his own. The same afternoon Mallow dressed himself smartly and strolled down to Kensington through the park. Without any difficulty he found Amelia Street. It proved to be in the centre of a fashionable locality, and its inhabitants were evidently people of wealth. As he mounted the steps of No. 30 he could not help wondering at Mrs. Arne's connection with the very shady matter he had in hand. For the moment the clue did not look promising. "Is Mrs. Arne at home?" he asked the footman who came to the door. "Mrs. Arne, sir?" said the man with a stare; "I know no one of that name, sir." Mallow felt a sudden shock of surprise at the unexpectedness of the answer. "But this is Mrs. Arne's house, surely?" he asked hastily. "No, sir," replied the man, "Mr. Dacre lives here." "Is Mr. Dacre in?" demanded Laurence, after a few moment's reflection. "He is not, sir; Mr. Dacre is at present out of town, sir. Mrs. Dacre is at home, sir." "In that case, please give her my card, and ask her if she will be so good as to see me for a few moments."