Investigating magistrate since 1859, he had rapidly acquired the most
brilliant reputation. Laborious, patient, and acute, he knew with
singular skill how to disentangle the skein of the most complicated
affair, and from the midst of a thousand threads lay hold to the right
one. None better than he, armed with an implacable logic, could
solve those terrible problems in which X--in algebra, the unknown
quantity--represents the criminal. Clever in deducing the unknown from
the known, he excelled in collecting facts, and in uniting in a
bundle of overwhelming proofs circumstances the most trifling, and in
appearance the most insignificant.

Although possessed of qualifications for his office so numerous and
valuable, he was tremblingly distrustful of his own abilities and
exercised his terrible functions with diffidence and hesitation. He
wanted audacity to risk those sudden surprises so often resorted to by
his colleagues in the pursuit of truth.

Thus it was repugnant to his feelings to deceive even an accused person,
or to lay snares for him; in fact the mere idea of the possibility of a
judicial error terrified him. They said of him in the courts, "He is
a trembler." What he sought was not conviction, nor the most probable
presumptions, but the most absolute certainty. No rest for him until the
day when the accused was forced to bow before the evidence; so much
so that he had been jestingly reproached with seeking not to discover
criminals but innocents.

The chief of detective police was none other than the celebrated Gevrol.
He is really an able man, but wanting in perseverance, and liable to be
blinded by an incredible obstinacy. If he loses a clue, he cannot bring