La Brinvilliers was a depraved woman, and Sainte-Croix made her a monster. She managed, by degrees, to poison, first, her own father (with whom she was living, on the hypocritical pretence of taking care of him in his declining years), next her two brothers, and then her sister; the father out of revenge, and the others for their fortunes. The histories of more than one poisoner bear terrible evidence that this description of crime assumes the form of an irresistible passion. Just as a chemist makes experiments for the pleasure and the interest of watching them, poisoners have often, without the smallest ulterior object, killed persons whose living or dying was to them a matter of complete indifference. The sudden deaths of a number of paupers, patients at the Hôtel Dieu, a little time after the events just alluded to, led to suspicion that the bread which La Brinvilliers was in the habit of giving them every week (by way of an example of piety and benevolence) was poisoned. And it is certain that she poisoned pigeon pasties which were served up to guests whom she had invited. The Chevalier du Guet, and many more, were the victims of those diabolical entertainments. Sainte-Croix, his accomplice La Chaussée, and La Brinvilliers, managed to hide their crimes for a long while under a veil of impenetrable secrecy. But, however the wicked may brazen matters out, there comes a time when the Eternal Power of Heaven punishes the criminal, even here on earth. The poisons which Sainte-Croix prepared were so marvellously delicate that if the powder (which the Parisians appositely named "_poudre de succession_") was uncovered while being made, a single inhalation of it was sufficient to cause immediate death. Therefore Sainte-Croix always wore a glass mask when at work. This mask fell off one day just as he was shaking a finished powder into a phial, and, having inhaled some of the powder, he fell dead in an instant. As he had no heirs, the law courts at once placed his property under seal, when the whole diabolical arsenal of poison-murder which had been at the villain's disposal was discovered, and also the letters of Madame de Brinvilliers, which left no doubt as to her crimes. She fled to a convent at Liège. Desgrais, an officer of the Marechaussée, was sent after her. Disguised as a priest, he got admitted into the convent, and succeeded in involving the terrible woman in a love-affair, and in getting her to grant him a clandestine meeting in a sequestered garden outside the town. When she arrived there she found herself surrounded by Desgrais' myrmidons; and her ecclesiastical gallant speedily transformed himself into the officer of the Marechaussée, and compelled her to get into the carriage which was waiting outside the garden, and drove straight away to Paris, surrounded by an ample guard. La Chaussée had been beheaded previously to this, and La Brinvilliers suffered the same death. Her body was burnt, and its ashes scattered to the winds.