For an unpleasant moment the detective wondered if she had merely made a mistake, or whether the whole tale were a fabrication. He remembered uneasily the readiness with which he had accepted it and his urgent pressing upon the voluble lady of the reward offered in the papers. No doubt she was laughing at his gullibility, and regaling her friends with an embellished account of how easily she had taken in the well-known detective. Gimblet’s lips tightened as he thought of it. Was he becoming unduly credulous in his old age? There was the story Sidney had told him, too. He had assured himself that he had kept an open mind as to the truth of it, and had reserved his opinion till proofs were offered him; but, as a matter of fact, as he now acknowledged sardonically, he had believed every word spoken by the young man, and allowed himself to be absurdly influenced by an honest face and an appearance of frank trustfulness.

“A nice sort of detective you are!” said Gimblet to his reflection in the little slip of looking-glass that adorned the cab; and he cried to the driver to go back to Whitehall.

Higgs was waiting for him, and reported that he had taken a second advertisement to the advertising agents, and that he had also been to most of the principal taxi garages, where he had made inquiries and posted notices.

“The man is sure to turn up to-morrow morning, sir,” he said.

In the morning there was no news. Gimblet telephoned to Grosvenor Street and was himself called up by Sidney. To him he replied coldly that so far he had nothing to report. Directly after breakfast Sir Gregory arrived, panting. “I couldn’t get you on the telephone,” he said. “Have you heard nothing?”

“I had an answer to my advertisement,” replied Gimblet, “but I am afraid the information brought me was quite unreliable.”

He told Sir Gregory in a few words of Miss Finner’s visit.

“I tested her story pretty severely yesterday,” he said, “but there still remains a chance that the man who drove her may appear, and be able to remember the exact route by which he took her on Monday night. There is no doubt her own account is so inaccurate as to be worthless; and it is possible,” he added, owning the secret dread he could not keep from his thoughts, “that she was only indulging in a kind of practical joke.”

Sir Gregory was beginning to show the effect of his days of anxiety. Though his face was still pink, the lines on it seemed to have become deeper and more numerous, and he had the weary, listless air of one to whom sleep has denied herself. Gimblet was not anxious for his company, but Sir Gregory would not be shaken off. The detective said he had letters to write and business that must be attended to; but was met by a pleading request to be allowed to remain, in case the taxi driver should make his appearance.

“I don’t know what to do with myself if I go away,” said Sir Gregory miserably. “If I am here I feel that, if any news does come, I shan’t have to wait longer than is necessary for it. Nothing like being at headquarters.”