Five miles above Prades is Villefranche, the terminus of the railway. It is a dreary little place built of grey marble that discolours and stains black. Moreover, it consists of two streets only, usually empty; and the houses are too many for the small population, numbering less than five hundred. The town was built by William Raymond, Count of Cerdagne, in 1095. He surrounded the town with a wall flanked by towers. The castle was erected by Vauban, on a spur of the limestone mountain of Belloch, 450 feet above the river Tet, and reached by a subterranean staircase of 999 steps. In this castle were confined for the rest of their lives two of the assistants of the infamous Marquise de Brinvilliers. These were La Chappelain and Guesdon. A very brief notice of the Marchioness and her crimes must suffice. She was a young and beautiful woman, connected both by birth and marriage with some of the noblest families of France, and was married to the Marquis de Brinvilliers, a man of depraved conduct. She formed a guilty attachment for Sainte Croix, a gay, handsome man, who had learned in Italy the manufacture of slow poisons, especially the Succession Powder. The Marquis and Marchioness separated, but were not divorced. Sainte Croix, who had no fortune of his own, depended on what was given him by his mistress, and as this did not suffice, he proposed to her to poison her old father and brothers and sister, so as to gather into her own hands all their succession. She agreed without hesitation, and herself administered the fatal draught to her father. The brothers were next got rid of, and the sister would have been similarly destroyed had not her suspicions been roused, and she hastily quitted Paris. Others who were inconvenient in one way or another were similarly got rid of, but all was done with such caution that no charge could be made against either. But the day of retribution was at hand, and a terrible mischance brought the murders to light. The nature of the poisons was so deadly that when Sainte Croix worked in his laboratory, he was obliged to wear a mask, to preserve himself from suffocation. One day the mask slipped off, and the miserable wretch perished in his crimes. His corpse was found on the following morning in the obscure lodging where he had fitted up his laboratory, and with it papers which disclosed the whole series of murders perpetrated by the pair. The Marchioness fled to England, where she remained for three years, but went early in 1676 to Liège. There she was caught, brought to Paris, executed, and her body burnt.