The few existing altar-pieces of Giotto are less important than his frescoes, inasmuch as they do not admit of the exhibition of his higher and most original gifts. Two signed examples are a _Coronation of the Virgin_ in Santa Croce at Florence, and a _Madonna_, with saints and angels on the side panels, originally in S. Maria degli Angeli at Bologna, and now in the Brera at Milan. The latter, however, is not now recognised as his. The earliest authentic example is the so-called Stefaneschi altar-piece, painted in 1298 for the same patron who commissioned the _Navicella_. Giotto's highest merit consists especially in the number of new subjects which he introduced, in the life-like and spiritual expression with which he heightened all familiar occurrences and scenes, and in the choice of the moment of representation. In all these no earlier Christian painter can be compared with him. Another and scarcely less important quality he possessed is in the power of conveying truth of character. The faces introduced into some of his compositions bear an inward guarantee of their lively resemblance to some living model, and this characteristic seems to have been eagerly seized upon by his immediate followers for emulation, as is noticeable in two of the principal works--in the Bargello at Florence, and in the church of the Incoronata at Naples--formerly attributed to him but now relegated to his pupils. The portrait of Dante in a fresco on the wall of the Bargello shows a deep and penetrating mind, and in the _Sacraments_ at Naples we find heads copied from life with obvious fidelity and such a natural conception of particular scenes as brings them to the mind of the spectator with extraordinary distinctness. Of Giotto's numerous followers in the fourteenth century it is impossible in the present work to give any particular account, but of his influence at large on the practice as on the treatment and conception of painting at this stage of its development, one or two examples may be cited as typical of the progress he urged, such as the frescoes in the Campo Santo at Pisa. This wonderful cloister, which measures four hundred feet in length and over a hundred in width--traditionally the dimensions of Noah's ark--was founded by the Archbishop Ubaldo, before 1200, on his return from Palestine bringing fifty-three ships laden with earth from the Holy Land. On this soil it was erected, and surrounded by high walls in 1278. The whole of these walls were afterwards adorned with paintings, in two tiers.