Naturally, however, it is but seldom, and only in special cases, and as a last resort, that such a plan is adopted. Moreover, the authorities only consent to it when they hope to derive some important advantage, such as the capture of a whole band of criminals. For instance, the police perhaps arrest one of a band. Now, despite his criminal propensities the captured culprit often has a certain sense of honor--we all know that there is honor among thieves--which prompts him to refuse all information concerning his accomplices. In such a case what is to be done? Is he to be sent to the Assizes by himself, tried and convicted, while his comrades escape scot free? No; it is best to set him at liberty. The prison doors are opened, and he is told that he is free. But each after step he takes in the streets outside is dogged by skilful detectives; and soon, at the very moment when he is boasting of his good luck and audacity to the comrades he has rejoined, the whole gang find themselves caught in the snare. M. Segmuller knew all this, and much more, and yet, on hearing Lecoq’s proposition, he made an angry gesture and exclaimed: “Are you mad?” “I think not, sir.” “At all events your scheme is a most foolish one!” “Why so, sir? You will recollect the famous murder of the Chaboiseaus. The police soon succeeded in capturing the guilty parties; but a robbery of a hundred and sixty thousand francs in bank-notes and coin had been committed at the same time, and this large sum of money couldn’t be found. The murderers obstinately refused to say where they had concealed it; for, of course, it would prove a fortune for them, if they ever escaped the gallows. In the mean while, however, the children of the victims were ruined. Now, M. Patrigent, the magistrate who investigated the affair, was the first to convince the authorities that it would be best to set one of the murderers at liberty. His advice was followed; and three days later the culprit was surprised unearthing the money from among a bed of mushrooms. Now, I believe that our prisoner--” “Enough!” interrupted M. Segmuller. “I wish to hear no more on the matter. I have, it seems to me, forbidden you to broach the subject.” The young detective hung his head with a hypocritical air of submission. But all the while he watched the magistrate out of the corner of his eye and noted his agitation. “I can afford to be silent,” he thought; “he will return to the subject of his own accord.” And in fact M. Segmuller did return to it only a moment afterward. “Suppose this man were released from prison,” said he, “what would you do?” “What would I do, sir! I would follow him like grim death; I would not once let him out of my sight; I would be his shadow.” “And do you suppose he wouldn’t discover this surveillance?” “I should take my precautions.” “But he would recognize you at a single glance.”