The car drew up at Saint-Lazare, the wretched, sordid old prison which is still waiting to be pulled down.

The Prefect jumped out.  The door was opened at once.

“Is the prison governor there?” he asked.  “Quick! send for him, it’s urgent.”

Then, unable to wait, he at once hastened toward the corridors leading to the infirmary and, as he reached the first-floor landing, came up against the governor himself.

“Mme. Fauville,” he said, without waste of time.  “I want to see her—­”

But he stopped short when he saw the expression of consternation on the prison governor’s face.

“Well, what is it?” he asked.  “What’s the matter?”

“Why, haven’t you heard, Monsieur le Prefet?” stammered the governor.  “I telephoned to the office, you know—­”

“Speak!  What is it?”

“Mme. Fauville died this morning.  She managed somehow to take poison.”

M. Desmalions seized the governor by the arm and ran to the infirmary, followed by Perenna and Mazeroux.

He saw Marie Fauville lying on a bed in one of the rooms.  Her pale face and her shoulders were stained with brown patches, similar to those which had marked the bodies of Inspector Verot, Hippolyte Fauville, and his son Edmond.

Greatly upset, the Prefect murmured: 

“But the poison—­where did it come from?”

“This phial and syringe were found under her pillow, Monsieur le Prefet.”

“Under her pillow?  But how did they get there?  How did they reach her?  Who gave them to her?”

“We don’t know yet, Monsieur le Prefet.”

M. Desmalions looked at Don Luis.  So Hippolyte Fauville’s suicide had not put an end to the series of crimes!  His action had done more than aim at Marie’s death by the hand of the law:  it had now driven her to take poison!  Was it possible?  Was it admissible that the dead man’s revenge should still continue in the same automatic and anonymous manner?

Or rather—­or rather, was there not some other mysterious will which was secretly and as audaciously carrying on Hippolyte Fauville’s diabolical work?

* * * * *

Two days later came a fresh sensation:  Gaston Sauverand was found dying in his cell.  He had had the courage to strangle himself with his bedsheet.  All efforts to restore him to life were vain.

On the table near him lay a half-dozen newspaper cuttings, which had been passed to him by an unknown hand.  All of them told the news of Marie Fauville’s death.

CHAPTER FIFTEEN

THE HEIR TO THE HUNDRED MILLIONS

On the fourth evening after the tragic events related, an old cab-driver, almost entirely hidden in a huge great-coat, rang at Perenna’s door and sent up a letter to Don Luis.  He was at once shown into the study on the first floor.  Hardly taking time to throw off his great-coat, he rushed at Don Luis: