The failure to produce adequate results of scale in the interiors of the larger Italian churches, has been already alluded to. It is strikingly exemplified in the Duomo at Florence, the nave of which is 72 feet wide, with four pier-arches each over 55 feet in span. The immense vault, in square bays, starts from the level of the tops of these arches. The interior (Fig. 148) is singularly naked and cold, giving no conception of its vast dimensions. The colossal dome is an early work of the Renaissance (see p. 276). It is not known how _Fr. Talenti_, who in 1357 enlarged and vaulted the nave and planned the east end, proposed to cover the great octagon. The east end is the most effective part of the design both internally and externally, owing to the relatively moderate scale of the 15 chapels which surround the apsidal arms of the cross. In S. Petronio at Bologna, begun 1390 by _Master Antonio_, the scale is better handled. The nave, 300 feet long, is divided into six bays, each embracing two side chapels. It is 46 feet wide and 132 feet high, proportions which approximate those of the French cathedrals, and produce an impression of size somewhat unusual in Italian churches. +Orvieto+ has internally little that suggests Gothic architecture; like many Franciscan and Dominican churches it is really a timber-roofed basilica with a few pointed windows. The mixed Gothic and Romanesque interior of +Sienna Cathedral+ (Fig. 150), with its round arches and six-sided dome, unsymmetrically placed over the crossing, is one of the most impressive creations of Italian mediæval art. Alternate courses of black and white marble add richness but not repose to the effect of this interior: the same is true of Orvieto, and of some other churches. The basement baptistery of +S. Giovanni+, under the east end of Sienna Cathedral, is much more purely Gothic in detail. In these, and indeed in most Italian interiors, the main interest centres less in the excellence of the composition than in the accessories of pavements, pulpits, choir-stalls, and sepulchral monuments. In these the decorative fancy and skill of the Italians found unrestrained exercise, and produced works of surpassing interest and merit. +EXTERNAL DESIGN.+ The greatest possible disparity generally exists between the sides and west fronts of the Italian churches. With few exceptions the flanks present nothing like the variety of sky-line and of light and shade customary in northern and western lands. The side walls are high and flat, plain, or striped with black and white masonry (Sienna, Orvieto), or veneered with marble (Duomo at Florence) or decorated with surface-ornament of thin pilasters and arcades (Lucca). The clearstory is low; the roof low--pitched and hardly visible from below. Color, rather than structural richness, is generally sought for: Milan Cathedral is almost the only exception, and goes to the other extreme, with its seemingly countless buttresses, pinnacles and statues.