Gismondo called to his aid some of the greatest artists of this time: Matteo da Pasti, the medallist, to execute the great marble medallions of himself, to be set up everywhere in the holy place; Ciuffagni for the statutes (a miserable choice), Simone Ferrucci for the bas-reliefs of playing children, Agostino Duccio, that exquisite draughtsman in marble, to carve in low relief the yellow-white plaques with allegorical figures, whose flowing lines of floating and twisted drapery, small well-poised heads, wonderful grace of attitude, and refined exotic type, recall the late Greek bas-reliefs rather than the solid, somewhat squat forms of Donatello and his school, or the angular delicacy of Mino. Over all these Gismondo set Leon Battista Alberti, a man almost as universal in his attributes as Leonardo himself. Alberti was to be the architect, and assign with Matteo’s aid their several parts to each of his co-operators. No easy task, this of Alberti’s; for Gismondo—with a flash of the native superstition which shot so strangely athwart his paganism—refused to destroy the consecrated walls of the older building. The architect must build his Hellenic temple on to the framework of a thirteenth-century Gothic church. Fortunately, the form of the early edifice, its wide nave and simple sanctuary not greatly differing from the Roman Basilica, rendered the conversion within the limits of possibility, and Alberti appears to have enjoyed the difficulty of his task. Perhaps he saw in this endeavour to fuse into one splendid whole the opposite characters of Gothic mediævalism and Greek antiquity, the opportunity to immortalize the spirit of his time—and the result was success. It is built, this temple of Rimini, of Roman stones from Classis, antique slabs from Greece, and of the Adriatic clay fused long ago by pious hands. Augustan arches rise without, sheltering the sarcophagi of philosophers, and within, the light from mediæval windows falls on the altar of a Christian saint. A pagan church, with pointed Gothic arches raised on sculptured classic pillars, a splendid anomaly, chiefly original by its combination of opposing elements, it is a type of the Italian Renaissance.
Finding it impossible to turn the Gothic front with its deep porch and rosace to any classical account, Alberti resolved to inclose it in a marble casing, distant at all points by nearly four feet from the original structure. He was now free to plan his façade, singularly simple in design, yet solemn, beautiful, and stately in its plainness. From a breast-high plinth, giving a noble base to the whole structure, start three engaged arches, the central one larger than the others and higher in relief; the span of all three is extremely wide, their proportions being borrowed from the Roman arch of Augustus close at hand. At the corners of the façade and on either side of the central arch stand four fluted columns with florid capitals; rising from the plinth they support a heavy, deep-shadowed cornice. Sculptured votive wreaths, six in all, are hung between the capitals of the columns and the spandrel of the arches. From the deep cornice above rises the pediment, unfinished and irregular, its supporting columns incomplete. Above this again should have sprung a cupola, vaulting the entire church in its wide span; but in its stead a temporary roof still patches the never-finished masterpiece.