Gentleman Jack had lowered his revolver, and was standing waitingto explain all, with the insufferable look of the man who is justgoing to say that he has only done his duty and requires nothanks.

　　"Who are you?" he said.

　　"Nev' min' who I am!" said Miss Trimble curtly. "Siz Pett knowswho I am.""I hope you won't be offended, Lord Wisbeach," said Mrs. Pettfrom the group by the door. "I engaged a detective to help you. Ireally thought you could not manage everything by yourself. Ihope you do not mind.""Not at all, Mrs. Pett. Very wise.""I'm so glad to hear you say so.""An excellent move."Miss Trimble broke in on these amiable exchanges.

　　"Whassall this? Howjer mean--help me?""Lord Wisbeach most kindly offered to do all he could to protectmy nephew's explosive," said Mrs. Pett.

　　Gentleman Jack smiled modestly.

　　"I hope I have been of some slight assistance! I think I camedown in the nick of time. Look!" He pointed to the safe. "He hadjust got it open! Luckily I had my pistol with me. I covered him,and called for help. In another moment he would have got away."Miss Trimble crossed to the safe and inspected it with a frown,as if she disliked it. She gave a grunt and returned to her placeby the window.

　　"Made good job 'f it!" was her comment.

　　Ann came forward. Her face was glowing and her eyes shone.

　　"Do you mean to say that you found Jimmy breaking into the safe?

　　I never heard anything so absurd!"Mrs. Pett intervened.

　　"This is not James Crocker, Ann! This man is an impostor, whocame into the house in order to steal Willie's invention." Shelooked fondly at Gentleman Jack. "Lord Wisbeach told me so. Heonly pretended to recognise him this afternoon."A low gurgle proceeded from the open mouth of little Ogden. Theproceedings bewildered him. The scene he had overheard in thelibrary between the two men had made it clear to him that Jimmywas genuine and Lord Wisbeach a fraud, and he could notunderstand why Jimmy did not produce his proofs as before. He wasnot aware that Jimmy's head was only just beginning to clear fromthe effects of the blow on the chin. Ogden braced himself forresolute lying in the event of Jimmy calling him as a witness.

　　But he did not intend to have his little business propositiondragged into the open.

　　Ann was looking at Jimmy with horror-struck eyes. For the firsttime it came to her how little she knew of him and how verylikely it was--in the face of the evidence it was almostcertain--that he should have come to the house with the intentionof stealing Willie's explosive. She fought against it, but avoice seemed to remind her that it was he who had suggested theidea of posing as Jimmy Crocker. She could not help rememberinghow smoothly and willingly he had embarked on the mad scheme.