The painting of the wreath which surrounds the shield is usually very beautiful, and the two flying angels or _amorini_ are models of grace. This motive of the wreath held by two flying figures was largely used by the Florentine sculptors of the fifteenth century, such as Ghiberti and Luca della Robbia; it was suggested by the similar design, of very inferior execution, which occurs on so many ancient Roman sarcophagi. _Classical influence._ Some of the most elaborate Italian manuscripts of the second half of the fifteenth century are decorated with very minutely and cleverly painted copies of antique classical gems, cameos, coins and medals, or reliefs in marble and bronze. Wonderful skill is often shown by the way in which the illuminator has given the appearance of relief and the actual texture of the metal or stone[188]. Beautiful as the borders of this class are, they belong to a period of decadence of taste, though not of skill, and they paved the way for the elaborate futilities of Giulio Clovio and other miniaturists of the sixteenth century period of decadence. _Capture of Constantinople._ The influx of Greek exiles into Florence, after the conquest of Constantinople by the Ottoman Turks in 1453, led to the famous revival of classical learning, and for a while made Florence not only the artistic but the intellectual centre of the world. Many of these fugitive Greeks brought with them both Greek and Latin manuscripts of ancient date, and a new development of manuscript art took place in consequence of this. _Copyism of early writing._ Though manuscripts of Service books and other sacred works continued to be written in the mediaeval "Gothic" form of character, for secular manuscripts[189] a very beautiful kind of "Roman" hand was largely used by the scribes of Florence, Venice and other Italian centres of the illuminator's art. This newly developed mode of writing was based on the beautiful clear form of character which had been used by the most skilful northern scribes of the ninth and tenth century; and at the same time a style of illumination for borders and initials was imitated or rather adapted, with the utmost taste and skill from the characteristic interlaced patterns of England, France and Germany during the twelfth century. _Celtic style of ornament._ This beautiful kind of ornament consists of delicately interlaced and plaited bands of white or gold, thrown into relief by filling in the background, or spaces between the laced bands, with alternating colours, blue, red and green. This style of initial was also largely used for the early printed books of Rome, Florence and Venice[190], many copies of which were illuminated in the most magnificent way, quite equal to the ornaments of the finest vellum manuscripts.