The judge nodded in acquiescence and directed the guard to take the prisoner into the outer office and have something to eat brought in for him.

“Well,” he asked when they were alone, “what is it?”

Then, for several minutes Coquenil talked earnestly, convincingly, while the magistrate listened.

“It ought not to take more than an hour or so to get the things here,” concluded the detective, “and if I read the signs right, it will just about finish him.”

“Possibly, possibly,” reflected the judge.  “Anyhow it’s worth trying,” and he gave the necessary orders to his clerk.  “Let Tignol go,” he directed.  “Tell him to wake the man up, if he’s in bed, and not to mind what it costs.  Tell him to take an auto.  Hold on, I’ll speak to him myself.”

The clerk waited respectfully at the door as the judge hurried out, whereupon Coquenil, lighting a cigarette, moved to the open window and stood there for a long time blowing contemplative smoke rings into the quiet summer night.

CHAPTER XXV

THE MOVING PICTURE

“Are you feeling better?” asked the judge an hour later when the accused was led back.

“Yes,” answered Groener with recovered self-possession, and again the detective noticed that he glanced anxiously at the clock.  It was a quarter past eleven.

“We will have the visual test now,” said Hauteville; “we must go to another room.  Take the prisoner to Dr. Duprat’s laboratory,” he directed the guard.

Passing down the wide staircase, strangely silent now, they entered a long narrow passageway leading to a remote wing of the Palais de Justice.  First went the guard with Groener close beside him, then twenty paces, behind came M. Paul and the magistrate and last came the weary clerk with Maitre Cure.  Their footsteps, echoed ominously along the stone floor, their shadows danced fantastically before them and behind them under gas jets that flared through the tunnel.

“I hope this goes off well,” whispered the judge uneasily.  “You don’t think they have forgotten anything?”

“Trust Papa Tignol to obey orders,” replied Coquenil.  “Ah!” he started and gripped his companion’s arm.  “Do you remember what I told you about those alleyway footprints?  About the pressure marks?  Look!” and he pointed ahead excitedly.  “I knew it, he has gout or rheumatism, just touches that come and go.  He had it that night when he escaped from the Ansonia and he has it now.  See!”

The judge observed the prisoner carefully and nodded in agreement.  There was no doubt about it, as he walked Groener was limping noticeably on his left foot!

Dr. Duprat was waiting for them in his laboratory, absorbed in recording the results of his latest experiments.  A kind-eyed, grave-faced man was this, who, for all his modesty, was famous over Europe as a brilliant worker in psychological criminology.  Bertillon had given the world a method of identifying criminals’ bodies, and now Duprat was perfecting a method of recognizing their mental states, especially any emotional disturbances connected with fear, anger or remorse.