ON the day after Isabel’s departure, diligent Mr. Troy set forth for the Head Office in Whitehall to consult the police on the question of the missing money. He had previously sent information of the robbery to the Bank of England, and had also advertised the loss in the daily newspapers. The air was so pleasant, and the sun was so bright, that he determined on proceeding to his destination on foot. He was hardly out of sight of his own offices when he was overtaken by a friend, who was also walking in the direction of Whitehall. This gentleman was a person of considerable worldly wisdom and experience; he had been officially associated with cases of striking and notorious crime, in which Government had lent its assistance to discover and punish the criminals. The opinion of a person in this position might be of the greatest value to Mr. Troy, whose practice as a solicitor had thus far never brought him into collision with thieves and mysteries. He accordingly decided, in Isabel’s interests, on confiding to his friend the nature of his errand to the police. Concealing the name, but concealing nothing else, he described what had happened on the previous day at Lady Lydiard’s house, and then put the question plainly to his companion. “What would you do in my place?” “In your place,” his friend answered quietly, “I should not waste time and money in consulting the police.” “Not consult the police!” exclaimed Mr. Troy in amazement. “Surely, I have not made myself understood? I am going to the Head Office; and I have got a letter of introduction to the chief inspector in the detective department. I am afraid I omitted to mention that?” “It doesn’t make any difference,” proceeded the other, as coolly as ever. “You have asked for my advice, and I give you my advice. Tear up your letter of introduction, and don’t stir a step further in the direction of Whitehall.” Mr. Troy began to understand. “You don’t believe in the detective police?” he said.