But--to consider what we may know. Sisteron is an old Roman city, most strongly and picturesquely built in a narrow defile of the Durance. On one side the river is the high, bare rock of La Baume; on the other, a higher rock where houses, supporting each other by outstretched buttresses, seem to cling to the sheer hillside as shrubs in mountain crevasses, and are dominated and protected by a large and formidable fortress-castle that crowns the very top of the peak. The town walls are almost gone; the fortress is abandoned; since the Revolution there are no longer Bishops in Sisteron; but the old town has lost little of its war-like and romantic atmosphere of days when it commanded an important pass, and when the way across the Durance was guarded by a drawbridge, and a big portcullis that now stands in rusty idleness. [Illustration: "THE CHURCH TOWER STOOD OUT AGAINST THE ROCKY PEAKS."--ENTREVAUX.] It is claimed that the Bishopric of this stronghold was founded in the IV century, and grew and flourished mightily, until the Bishop dwelt securely on his rock, his Brother of Gap had a "box" on the opposite bank, the Convent of the little Dominican Sisters was further up the river, and, besides this busy ecclesiastical life, there was the world of burghers in the town and its Convent of Ursulines. Here came once upon a time a sprightly lady who added a thousand lively interests. This was Louise de Cabris, sister of the great Mirabeau, "who, when a mere girl, had been married to the Marquis de Cabris. Part knave, part fool, the vices of de Cabris sometimes ended in attacks of insanity. His marriage with one who united the violence of the Mirabeaus to the license of the Vassans was unfortunate; ... and after Louise began to reign in the big dark house of the Cours of Grasse, life never lacked for incidents." Matters were not mended by the arrival of her brother, twenty-four and wild, and supposed to be living under a "lettre de cachet" in the sleepy little town of Manosque. The two were soon embroiled in so outrageous a scandal that their father, who loved a quarrel for its own sake, sided with the prosecution; and declaring that "no children like his had ever been seen under the sun," took out a "lettre de cachet" for Louise, who was sent up to Sisteron, where he requested her to "repent of her sins at leisure in the Convent of the Ursulines." Inheriting a brilliant, restless wit and unbridled morals, her life with the stupid, vicious Marquis had not improved her natural disposition, and she soon set Sisteron agog. On pretence of business all the lawyers flocked to see her; and with no pretence at all the garrison flocked in their train. When the Ursulines ventured to remonstrate, she diverted them with such anecdotes of gay adventure as were never found between the pages of their prayer-books. Finally the whole town was divided into two camps; her foes called her "a viper," and many an eye