"Please have him shown in."
And, turning to Perenna:
"Sergeant Mazeroux is one of our smartest detectives. I used to employ him together with that poor Vérot when I wanted any one more than ordinarily active and sharp. He will be of great use to you."
Sergeant Mazeroux entered. He was a short, lean, wiry man, whose drooping moustache, heavy eyelids, watery eyes, and long, lank hair gave him a most doleful appearance.
"Mazeroux," said the Prefect, "you will have heard, by this time, of your comrade Vérot's death and of the horrible circumstances attending it. We must now avenge him and prevent further crimes. This gentleman, who knows the case from end to end, will explain all that is necessary. You will work with him and report to me to-morrow morning."
This meant giving a free hand to Don Luis Perenna and relying on his power of initiative and his perspicacity. Don Luis bowed:
"I thank you, Monsieur le Préfet. I hope that you will have no reason to regret the trust which you are good enough to place in me."
And, taking leave of M. Desmalions and Maître Lepertuis, he went out with Sergeant Mazeroux.
As soon as they were outside, he told Mazeroux what he knew. The detective seemed much impressed by his companion's professional gifts and quite ready to be guided by his views.
They decided first to go to the Café du Pont-Neuf. Here they learned that Inspector Vérot, who was a regular customer of the place, had written a long letter there that
