ill trouble myself no more about the
matter."

He said this, but the anxiety and disappointment caused by defeat,
sneering criticism, and perplexity, as to the best course to be pursued,
so affected his health that he became really ill--so ill that he had to
take to his bed.

He had been confined to his room for a week or so, when one morning
Lecoq called to inquire after him.

"You see, my good fellow," quoth M. Segmuller, despondently, "that this
mysterious murderer is fatal to us magistrates. Ah! he is too much for
us; he will preserve the secret of his identity."

"Possibly," replied Lecoq. "At all events, there is now but one way left
to discover his secret; we must allow him to escape--and then track him
to his lair."

This expedient, although at first sight a very startling one, was not of
Lecoq's own invention, nor was it by any means novel. At all times, in
cases of necessity, have the police closed their eyes and opened the
prison doors for the release of suspected criminals. And not a few,
dazzled by liberty and ignorant of being watched, have foolishly
betrayed themselves. All prisoners are not like the Marquis de
Lavalette, protected by royal connivance; and one might enumerate
many individuals who have been released, only to be rearrested after
confessing their guilt to police spies or auxiliaries who have won their
confidence.

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