Among the churches of the Venetian Renaissance San Zaccaria is one of the earliest, and its interior exhibits a singular mixture of those mediæval and pseudo-classic forms of which the Italian architects produced such an astonishing variety. To an apse with a half dome and pseudo-Gothic substructure is joined a nave of three square bays, the first of which is covered with a dome on pendentives, while each of the others has a plain groined vault. These vaults spring from an entablature which crowns the great arcade, and is returned on the ends of the building, with ressauts on corbels at the imposts. The aisles have oblong groined vaults on pointed transverse arches springing from corbels on the wall side, and tied with iron rods. The main proportions conform with those of the so-called Italian Gothic churches, the great arcades of the nave, and consequently the aisle vaulting, being relatively very high. The most singular feature of this interior is the column (Fig. 86) of nondescript character, and a variant of the tapering Lombard Renaissance shaft of Pavia and Como. It consists of a shaft of pseudo-Corinthian form raised on a high octagonal pedestal, with a very wide and richly moulded base. [Illustration: FIG. 86.] The church of San Salvatore, dating from the close of the fifteenth century, and attributed to the architect Tullio Lombardo, though begun by Spavento,[109] has a modified Byzantine structural scheme applied to a long nave with three domes on pendentives separated by short sections of barrel vaulting. The supports (Fig. 87) of this vaulting are peculiar, and are like the piers of the nave of St. Andrea of Mantua modified by piercing them both transversely and longitudinally so as to leave four slender solid parts at the angles (two of which are engaged in the aisle wall), the void being covered with a diminutive dome on pendentives. The plan of the structure as a whole suggests this comparison with St. Andrea, but the character of the supports suggests their derivation from the piers of the church of St. Mark. These last are square masses of masonry pierced longitudinally and transversely so as to leave four heavy solids as in Figure 88, the void in this case being covered with a diminutive groined vault. In San Salvatore the solids are greatly reduced in volume, and are faced with neo-classic pilasters, above which the pier is solid, and is faced with an entablature surmounted by an attic from which the vaulting springs. The use of an attic in an interior, and especially as a support for vaulting, is one of those architectural aberrations with which the Renaissance has made us familiar. I know not when or where it first occurred, but there can be few earlier instances than this. It was not seldom introduced by the architects of the later Renaissance, and, as we shall see, by Sir Christopher Wren in St. Paul’s cathedral. It is worthy of notice that the system of San Salvatore is that of the church of St.