Briancourt asked himself whether all that he heard and saw were real events in a real world. How far had this terrible woman been to seek her accomplices? How far had she pushed her crimes?

‘Two days afterwards,’ continues Briancourt, ‘the marquise told me that Monsieur Bocager was not so upright a man as I imagined, as I should see some day. And as I was passing down the street in the evening, just opposite St. Paul’s, two pistol-shots were fired at me, without my being able to tell whence they came, and one of them pierced my coat. Seeing that I was marked down, I went next day to Sainte-Croix’ house, carrying two pistols, having left a man at the street door to see that it remained open. I told Sainte-Croix that he was a villain and a scoundrel, that he would be broken on the wheel, and that he had caused the death of several people of quality. He declared that he had never caused anybody’s death, but that if I would go behind the Hôpital Général with pistols he would give me every kind of satisfaction; to which I replied that I was not a soldier, but that if I were attacked I should defend myself.’

Such was the strange existence of the poor bachelor in theology, tutor to the children of the Marquis de Brinvilliers. In his fear of poison he was continually swallowing some nostrum or other by way of antidote.

The marquis himself lived in equal terror. He knew what was going on, and took things philosophically. Here is a sketch of a dinner at his house. ‘The marchioness put Sainte-Croix on her right; the marquis was at the sideboard end of the table. The latter was very carefully served by a domestic specially attached to his person, to whom he always said: “Don’t change my glass, but rinse it every time you give me anything to drink.”’ When the evening was over, the marquis retired to his room; Sainte-Croix and the marchioness went to the lady’s room, and Briancourt went upstairs with the children. With the horrors of crime there were thus mingled scenes of burlesque.

Accommodating as her husband was, the marchioness began to poison him; then, struck with remorse, she called in to attend him one of the most famous physicians of the time, Dr. Brayer.

‘She wished to marry Sainte-Croix,’ writes Madame de Sévigné, ‘and with that intention often gave her husband poison. Sainte-Croix, not anxious to have so evil a woman as his wife, gave counter-poisons to the poor husband, with the result that, shuttlecocked about like this five or six times, now poisoned, now unpoisoned, he still remained alive.’ Brinvilliers emerged from this violent treatment with a weakness in the legs. Afterwards he always carried theriac about with him, that being regarded as an antidote; he took it from time to time, and gave doses to his people.

Briancourt, however, succeeded in escaping from the service of his formidable mistress, and, under the baleful impression of what he had seen in the world, he retired to Aubervilliers, where he lived in solitude, giving lessons in the establishment of the Fathers of the Oratory there. Seven or eight months had passed when the marchioness came to see him; then she sent from time to time to ask how he was doing. It was at Aubervilliers that one evening, on July 31, 1672, he received from his late mistress a very urgent note, begging him to go immediately to Picpus, where she had an important communication to make to him. There had just happened an event which was to entail incalculable consequences: on July 30 Sainte-Croix died in his mysterious dwelling in the cul-de-sac of the Place Maubert.

A widespread legend makes Sainte-Croix’ death the result of a chemical experiment; it is said that the glass mask with which he covered his face to protect it from the poisonous vapours had broken. But he really died a natural death after an illness of some months, in the course of which he was visited by several persons who have left their testimony in regard to the matter. In the legendary laboratory of the cul-de-sac there was found indeed a furnace of ‘digestion.’ Sainte-Croix ‘philosophised’ there, that is, worked at the philosopher’s stone, and more particularly at solidifying mercury, that eternal dream of the alchemists.

Madame de Brinvilliers soon learned of the death of her lover. Her first cry was, ‘The little box!’

II. HER TRIAL

Sainte-Croix died overwhelmed in debt. His things were all put under seal. The seals were raised on August 8, 1672, by Commissary Picard, assisted by a sergeant named Creuillebois, two notaries, the agent of the widow, and an agent of the creditors. The three first meetings had passed without incident when a Carmelite monk who was present handed to the commissary the key of the private room in which the furnace was kept. Entering, they saw on the table a rolled-up paper bearing the words, ‘My confession.’ The persons present decided without hesitation to keep the paper secret, and to burn it on the spot. They found, further, at the end of a shelf, a small box, oblong in shape and red in colour, from which hung a key. It contained some phials, some of which were filled with a clear liquid like water, others with a liquid of reddish colour; and in addition, there were the letters addressed by Madame de Brinvilliers to Sainte-Croix, the two promissory notes signed by the marchioness after the poisoning of her father and brothers, and a receipt and power of attorney relating to a sum of 10,000 livres lent by Pennautier, receiver-general of the clergy, to Monsieur and Madame de Brinvilliers through the agency of Sainte-Croix. These two last papers were in a sealed envelope on which was written: ‘Papers to be restored to the Sieur Pennautier, receiver-general of the clergy, as belonging to him; and I humbly beg those into whose hands they fall, to be good enough to return them to him at my death, they being of no consequence except to him alone.’

Sainte-Croix had addressed the little box, with its contents, to Madame de Brinvilliers in these terms: ‘I humbly beg those into whose hands this box falls to do me the favour to return it into the hands of the Marquise de Brinvilliers, who lives in Rue Neuve-Saint-Paul, since all that it contains concerns her and belongs to her alone, and moreover it is of no use to anybody in the world but herself; and in case she dies before I do, to burn it, and all that is in it, without opening it or meddling with it; and so that no one may pretend ignorance, I swear by the God I adore, and all that is most holy, that I state nothing but the truth. If perchance any one contravenes my intentions, just and reasonable as they are, I charge it in this world and the next upon his conscience, for discharge of my own, and declare that this is my last will. Made at Paris, afternoon, May 25, 1670. Signed: Sainte-Croix.’ Below were these words: ‘There is a single packet addressed to Monsieur Pennautier, which is to be given to him.’ The very energy of these formulæ impressed Commissary Picard. He sealed up the case and confided it to the care of two sergeants, Cluet and Creuillebois, so that the inventory might be made by the civil lieutenant in person. Sergeant Creuillebois took the box home.

It was Sainte-Croix’ widow who on August 8—that is, the day when the box was discovered—sent word to Madame de Brinvilliers at Picpus that things belonging to her were under seal. The marchioness instantly sent some one to find the box. As that was no longer in Sainte-Croix’ house, a servant was sent off to Commissary Picard to tell him that Madame de Brinvilliers desired to speak to him without delay. Picard answered that he was busy. The marchioness, however, herself hurried to Madame de Sainte-Croix, insisting on the box being given to her. It was nine o’clock at night. ‘She complained of its having been sealed up, offered money to obtain it, proposed to