Gothic architecture was eminently a product of the Isle de France. The thirteenth century rivals the finest period of Greek art for purity, simplicity, nobility and accurate science of construction. Imagination was chastened by knowledge, but not systematised into rigid rules. Each master solved his problem in his own way, and the result was a charm and a variety, a fertility of invention, never surpassed in the history of art. Early French sculpture is a direct descendant of Greek art, which made its way into France by the Phoenician trade route. French artists achieved a perfection in the representation of the human form which anticipated by a generation the work of the Pisani in Italy, for the statues on the west front of Chartres Cathedral (1150-1160) are carved with a naturalness and grace which the Italian masters never surpassed, and the marvellously mature and beautiful thirteenth-century silver-gilt figure of a king, in high relief, found in 1902 immured in an old house at Bourges and exhibited in 1904 among the Primitifs Français at the Louvre, was wrought more than a century before the birth of Donatello. Some fragments of the old sculptures that adorned St. Denis and other twelfth- and thirteenth-century churches may still be found in the museums of Paris. The influence of the French architects, as Emile Bertaux has demonstrated in the first volume of his _Art dans l'Italie Meridionale_, extended far beyond the limits of France, and is clearly traceable in the fine hunting-palace, erected for Frederic II. in the thirteenth century, at Castello del Monte, near Andria, in Apulia. But the names of those who created these wonderful productions no man knoweth; the great masterpieces of the thirteenth century are anonymous. Jean de Chelles, one of the masons of Notre Dame, has left his name on the south portal and the date, Feb. 12, 1257, on which it was begun, "in honour of the holy Mother of Christ," but nothing is known of him. The Sainte-Chapelle is commonly attributed to Pierre de Montereau, but the attribution is a mere guess. [Illustration: 13TH CENTURY SCULPTURES FROM ST. DENIS (RESTORED).] [Illustration: NOTRE DAME--SOUTHERN SIDE.]