Contemporaneously with Toffana, another Italian, Keli, devoted himself to similar crimes. This man had expended much as an adept searching for the philosopher’s stone, and sought to indemnify himself by entering upon what must have been a profitable business. He it was who instructed M. de St. Croix in the properties of arsenic; and St. Croix, in his turn, imparted the secret to his paramour, Madame de Brinvilliers. This woman appears to have been as cold-blooded as Toffana; she is said to have experimented on the patients at the Hôtel Dieu, in order to ascertain the strength of her powders, and to have invented “les poudres de succession.” She poisoned her father, brothers, sister, and others of her family; but a terrible fate overtook both her and St. Croix. The latter was suffocated by some poisonous matters he was preparing, and Madame de Brinvilliers’ practices having become known, she was obliged to take refuge in a convent. Here she was courted by a police officer disguised as an abbé, lured out of the convent, and, in this way brought to justice, was beheaded[13] and burnt near Nôtre Dame, in the middle of the reign of Louis XIV.[14] [13] The Marchioness was imprisoned in the Conciergerie and tortured. Victor Hugo, describing the rack in that prison, says, “The Marchioness de Brinvilliers was stretched upon it stark naked, fastened down, so to speak, quartered by four chains attached to the four limbs, and there suffered the frightful extraordinary torture by water,” which caused her to ask “How are you going to contrive to put that great barrel of water in this little body?”--_Things seen by Victor Hugo_, vol. i. The water torture was this:--a huge funnel-like vessel was fitted on to the neck, the edge of the funnel coming up to the eyes; on now pouring water into the funnel so that the fluid rises above the nose and mouth, the poor wretch is bound to swallow the fluid or die of suffocation; if indeed the sufferer resolve to be choked, in the first few moments of unconsciousness the fluid is swallowed automatically, and air again admitted to the lungs; it is therefore obvious that in this way prodigious quantities of fluid might be taken. [14] For the court of poisoners (_chambre ardente_) and the histories of St. Croix, De Brinvilliers, the priest Le Sage, the women La Voisin, and La Vigoureux, the reader may be referred to Voltaire’s _Siècle de Louis XIV._, Madame de Sévigné’s _Lettres_, Martinière’s _Hist. de la Règne de Louis XIV._, Strutzel, _De Venenis_, &c.