“With Cosmo Mornington, the thing was easy enough.  Introducing himself to the American as a doctor, Jean Vernocq put poison into one of the phials which Mornington used for his hypodermic injections.

“But in the case of Hippolyte Fauville, whose good will he had secured through his acquaintance with old Langernault, and over whose mind he soon obtained an extraordinary influence, he had a greater difficulty to contend with.  Knowing on the one hand that the engineer hated his wife and on the other that he was stricken with a fatal disease, he took occasion, after the consultation with the specialist in London, to suggest to Fauville’s terrified brain the incredible plan of suicide of which you were subsequently able to trace the Machiavellian execution.

“In this way and with a single effort, anonymously, so to speak, and without appearing in the business, without Fauville’s even suspecting the action brought to bear upon him, Jean Vernocq procured the deaths of Fauville and his son, and got rid of Marie and Sauverand by the devilish expedient of causing the charge of murder, of which no one could accuse him, to fall upon them.  The plan succeeded.

“There was only one hitch at the present time:  the intervention of Inspector Verot.  Inspector Verot died.  And there was only one danger in the future:  the intervention of myself, Don Luis Perenna, whose conduct Vernocq was bound to foresee, as I was the residuary legatee by the terms of Cosmo Mornington’s will.  This danger Vernocq tried to avert first by giving me the house on the Place du Palais-Bourbon to live in and Florence Levasseur as a secretary, and next by making four attempts to have me assassinated by Gaston Sauverand.

“He therefore held all the threads of the tragedy in his hands.  Able to come and go as he pleased in my house, enforcing himself upon Florence and later upon Gaston Sauverand by the strength of his will and the cunning of his character, he was within sight of the goal.

“When my efforts succeeded in proving the innocence of Marie Fauville and Gaston Sauverand, he did not hesitate:  Marie Fauville died; Gaston Sauverand died.

“So everything was going well for him.  The police pursued me.  The police pursued Florence.  No one suspected him.  And the date fixed for the payment of the inheritance was at hand.

“This was two days ago.  At that time, Jean Vernocq was in the midst of the fray.  He was ill and had obtained admission to the nursing-home in the Avenue des Ternes.  From there he conducted his operations, thanks to his influence over Florence Levasseur and to the letters addressed to the mother superior from Versailles.  Acting under the superior’s orders and ignorant of the meaning of the step which she was taking, Florence went to the meeting at the Prefect’s office, and herself brought the documents relating to her.

“Meanwhile, Jean Vernocq left the private hospital and took refuge near the Ile Saint-Louis, where he awaited the result of an enterprise which, at the worst, might tell against Florence, but which did not seem able to compromise him in any case.