That Chartres was a meeting place of the Druids, we know from Cæsar, and the XIII-century sons of the Gauls, as if in souvenir, carved the druidical oak leaf freely upon the present cathedral. Is it fanciful to feel that in the grave forest stillness of Chartres' interior lingers much of the theocratic nostalgia that forever haunts the Celt? In druidic times priest, teacher, and lawmaker were honored above brute force of arms. The present crypt of Chartres includes part of the Gallo-Roman walls. The V-century Merovingian cathedral abutted on the city ramparts. Then came wars which in part demolished the town walls, so that the reconstructed church was able to extend itself beyond the ramparts. It was doubtless after the Norman inroads that was built, in the IX century, the chapel of St. Lupus which forms the core of the present crypt. The Carolingian cathedral of Chartres was destroyed by a terrible fire in 1020. Now, in 1020, the see of Chartres was occupied by one of the notable bishops of French history, Fulbert (1007-29), revered of the people, a scholar enamored of the life of study, though the events of that agitated age forced him to play an active part in the national life. Like Abbot Suger, he was of lowly extraction. He had studied in the cathedral school of Rheims, made notable by Archbishop Gerbert, who later became Sylvester II, the pope of the year 1000. Fulbert, too, like his master, was a versatile genius--doctor in medicine as well as theologian, and one of the first to take up the new musical system of the Benedictine Guy d'Arezzo. He made the cathedral school of Chartres a center of learning, and men who were to be the leaders of the age were his pupils. Like Socrates, he taught his disciples as they paced up and down the cathedral precincts. In his exhortations there was an appealing tenderness that had a singular power in moving men's hearts, and letters from his pupils still exist, complaining of the exile they felt when separated from him.[107] To rebuild his cathedral, Bishop Fulbert gave up his own revenues. Gifts poured in from the kings of England and Denmark, from the bishop's schoolmate of Rheims, the good and cultivated King Robert of France, from the Duke of Aquitaine, who donated the treasure accumulated in St. Hilary's abbatial at Poitiers. The work was pushed forward with such energy that after four years Bishop Fulbert was able to write that, by winter, his lower church would be vaulted.