Our survey of Greek sculpture must conclude with the great buildings of Augustus. In them we see for the first time the combination of Italian with Greek principles. The Greco-Roman art which we have noticed hitherto has been archaistic and eclectic, but it has been purely Greek. Roman tastes have been studied and gratified, but style and technique have remained wholly Greek and uncontaminated. Even in the new buildings this procedure still continued. Pliny tells us that Augustus, who had the fashionable taste for the archaic in Greek art, actually imported the _Korai_ of Bupalos and Athenis for use as acroteria on his monuments. The Conservatori Museum contains an almost exact copy of one of these _Korai_,[123] which must belong to the age of Augustus, as well as a very inferior adaptation of the same type. The _Kore_ figure was translated into the so-called Spes type for mirror handles and other elements of decoration. But Augustus was not the man to submit to a complete extinction of Italian artistic principles. His system was closely identified with a revival of ancient Italy in all directions, and he was not likely to abandon Italic art. It therefore came to pass that in the greatest sculptured monument of his period--the Ara Pacis[124] erected on the Campus Martius, which is now being gradually and laboriously pieced together again--we have a combination of Greek and Italian principles of first-rate importance for the subsequent development of Roman art. One side of the altar contained a relief of Tellus or the Earth, which is hardly distinguishable from the pastoral Hellenistic reliefs, but the procession which fills the greater part of the other sides is treated in a very different manner. The general scheme is Greek, and must have been influenced by the Parthenon frieze, but the treatment in detail is Italian. Thus we have the Roman toga with its voluminous soft folds, and the Roman principle of direct realistic portraiture in all the heads. But more important than the portraiture is the appearance of a new development of perspective in relief which is destined to have a great career in the future of art, and which has been regarded by some authorities as purely Italian.