The ancient visitor would have found painting even more popular than sculpture in Rome’s temples and dwellings, porticoes and squares. He would have come upon many works of old masters there- Polygnotus, Zeuxis, Apelles Protogenes, and others- as dear to the opulent Empire as the paintings of the Renaissance are to rich America; and he would have seen in greater abundance, through their better preservation, the products of Alexandrian and Roman schools. The art was old in Italy, where every wall craved ornament. Once even Roman nobles had practiced it; but the Hellenistic invasion had made painting Greek and servile, and at last Valerius Maximus marveled that Fabius Pictor should have stooped to paint murals in the Temple of Health. There were exceptions: toward the end of the Republic Arellius made a name for himself by hiring prostitutes to pose for his goddesses; in the time of Augustus a dumb aristocrat, Quintus Pedius, took up painting because his defect closed most professions to him; and Nero employed for the interior of his Golden House one Amulius, who painted with the greatest gravity, always in his toga.” But such men were rari nantes in the crowd of Greeks who, at Rome and Pompeii and throughout the peninsula, made copies or variations of Greek paintings on Greek or Egyptian themes. The art was practically limited to fresco and tempera. In fresco a freshly plastered wall was painted with water-moistened colors; in tempera the pigments were mixed with an adhesive sizing and laid upon a dry surface. Portrait painters sometimes employed an encaustic process in which the tints were fused in hot wax. Nero had his picture painted on a canvas 120 feet high- the first known use of this material. Painting, as we have seen, was applied to statues, temples, stage scenery, and great linen pictures intended for exhibition in triumphs or in the Forum; but its favored receptacle was the external or internal wall. The Romans seldom placed furniture against a wall or hung pictures there; they preferred to use the entire space for one painting, or for a group of related designs. In this way the mural became a part of the house, an integral item in the architectural design.
The caustic humor of Vesuvius has preserved for us some 3500 frescoes- more paintings at Pompeii than can be found in all the rest of the classic world. Since Pompeii was a minor town we may imagine how many such murals brightened the homes and shrines of classic Italy. The best survivors have been removed to the Naples Museum; even there their lithe grace impresses us; but only the ancients knew them in the full depth of their color and in the architectural framework that gave each picture a function and a place. In the House of Vettii the murals have been left in situ: in a dining room Dionysus surprises the sleeping Ariadne; on the opposite wall Daedalus displays his wooden cow to Pasiphae; at the farther end Hermes looks on calmly as Hephaestus fastens Ixion to the torturing wheel; and in another room a succession of humorous frescoes shows carefree Cupids parodying the industries of Pompeii, including the wine business of the Vettii. The bite of time has gnawed into these once brilliant surfaces, but enough remains to shock the visitor into modesty; the figures are almost perfectly drawn, and so colorful with the flesh of life that they can still make the blood stir lustily in living veins.