Very different is the west front of San Francesco of Rimini, in which Alberti has introduced a Roman composition without any admixture of mediæval elements. It is substantially a reproduction of the arch of Septimius Severus. The details are in higher relief here in conformity with the ancient model, and the ressauts of the entablature become correspondingly more salient. A ressaut of this kind is another feature of Roman art which has no justification on structural grounds, and to which there is nothing analogous in any reasonable style of architecture. To set a useless column in advance of an entablature and then make a ressaut to cover it, is irrational. [Illustration: Plate II SANT’ANDREA Mantua] Alberti’s capital work in church architecture is Sant’Andrea of Mantua, begun in 1472, the year of the architect’s death, in which he made a frank return to Roman models in the structural forms of the whole edifice, as well as in the ornamental details--a thing that was rarely done by the architects of the Renaissance. The plan (Fig. 18) is, however, cruciform, and the dome over the crossing is supported in the Byzantine manner on pendentives. The nave (Plate II) has a barrel vault on massive square piers connected by arches, the intervals between the piers forming side chapels, and the lower part of each pier having a small square chamber within it, so that it does not look as massive on the plan as it does in elevation. The east end has the strictly Roman form of a semicircular apse with a half-dome vault. The details of the interior consist of a single order of pilasters, on high pedestals, set on the angles of the piers, and of rich Roman coffering on the surfaces of the vaulting. The piers closely resemble those of the so-called arch of the Silversmiths in Rome, which it is not unlikely that Alberti had in mind in designing them, inasmuch as he was a devoted student of Roman architectural antiquities. This interior is, I think, one of the very finest that the Renaissance produced. The justness of its proportions, the simplicity of the structural scheme, and the quietness of the ornamental details are all admirable. With the given elements it is hard to see how a better composition could be made; but the incongruity between the structural and ornamental systems, the entirely superficial use of the order, and its unfitness as ornament where it has no structural meaning, are fundamental defects of this as of most other Renaissance designs. The scheme of St. Andrea foreshadows that of St. Peter’s, and was undoubtedly in the mind of Bramante when he was preparing his colossal project for Pope Julius II. [Illustration: FIG. 18.--Sant’Andrea, Mantua.] [Illustration: FIG. 19.--Façade of Sant’Andrea, Mantua.]