For nearly three centuries it was imported into the city in a continuous flow from the quarries of Greece and Egypt. The native Luna marble, the modern Carrara, was not at first worked, but thousands of slaves and convicts toiled in the quarries of the Roman provinces. The great blocks were numbered and stamped with the name of the reigning emperor and shipped off in the great triremes across the Mediterranean to Ostia. Thence the trading vessels were towed by oxen up the river to Rome, their slow progress ceasing with nightfall, when they were drawn up and moored to the banks till next morning, bands of vigiles watching over the safety of their cargoes and restraining their lawless crews from acts of brigandage. At their journey's end, the cargoes were unloaded upon the marble wharf beneath the Aventine; here unused blocks still lie upon the site of the once busy Marmoratum, now a deserted quay beside a deserted river; and the harbour of Ostia, built by King Ancus Martius at the river's mouth, is now four miles inland.
Occasionally a granite obelisk was brought from Thebes or Heliopolis to adorn an imperial circus. That now in the Lateran Piazza is 108 feet in height and weighs 400 tons. Ships had to be built on purpose for the task, and one of these was so enormous that after safely conveying the Vatican obelisk to Rome, it was sunk by the Emperor Claudius to serve as a breakwater for the harbour at Porto. When the laden ships arrived at the Marmoratum the obelisks were hauled on shore by men and horses and then dragged and pushed on rollers along the streets by gangs of workmen. Forty-eight obelisks were once erected in Rome, of which thirty have disappeared and left no trace.
TEMPLE OF VESPASIAN FROM THE PORTICO OF THE DII CONSENTES
Built in honour of the first Flavian Emperor by his sons Titus and Domitian. The three remaining Corinthian columns are of Carrara marble. The Arch of Septimius Severus to the right was dedicated to the emperor and his sons Caracalla and Geta in a.d. 203, to commemorate their Parthian victories. It is of Pentelic marble. The church of Santa Martina in the background is near the site of the Senate House. See pages [31], [32].
While the fashion for marble lasted, no material was considered too rare or too costly. Parian marble, the most beautiful of all white marbles, from the island of Paros; Pentelic marble from Pentelicus; Hymettan marble from the mountains of Attica; rich yellow giallo antico from Numidia; cippolino with its beautiful green waves from Carystos; purple pavonazzo from Phrygia; black marble from Cape Matapan; green and red porphyries from Egypt; alabaster from Thebes; serpentine from Sparta; jasper and fluor-spar from Asia Minor; lapis lazuli, with which Titus paved a chamber in his baths, from Persia, besides countless varieties of the so-called Lumachella marbles and rare and beautiful breccias.
There arose in Rome an army of marble workers, cutters and sawyers, polishers and cleaners, carvers of simple mouldings and of inscriptions, and more skilled sculptors of ornament and of statues and busts.
Coloured marbles were first used in small pieces for making mosaic pavements. This art was introduced from Greece some time in the first century b.c., and in its simplest form was an arrangement of smooth pebbles in a rough pattern on a bed of cement. As the art developed, cubes, lozenges, and hexagons of travertine and grey lava were cut and fitted together in simple patterns. Then cubes of coloured marble were used, and the designs, of figures and flowers, became more elaborate. The floors were prepared with a bed of concrete, covered with several layers of cement; the last layer was carefully smoothed and levelled, and in this the cubes were fitted according to the pattern, and finally liquid cement was poured over the whole to fill in the cracks. When dry and hard the surface was polished with sand and water rubbed on with little marble blocks.
Pavements of the best building period can be recognised by the size of the cubes, about three to the inch, and by the neatness and finish of the work. Two varieties of mosaic can be distinguished, that in which marbles, stones, and coloured glass are cut into cubes only and the so-called sectile mosaic in which elaborate scenes and groups of figures are represented, the coloured pieces being sawn into shapes to fit in with the design. The Tablinum in the house of the vestals and the temple of Jupiter on the Capitol were paved with sectile mosaic. The most brilliant mosaic which came into use during the Empire for the decoration of walls and vaults was made of fragments of coloured marble and glass, the latter specially prepared with acids to make it opaque and to give it a brilliant appearance. The art of mosaic work has never died out entirely in Rome. The Roman mosaic pavements and mosaic wall decoration were copied by the builders of mediæval churches, and even now a mosaic factory is kept up at the Vatican.
Although first used in this way, coloured marbles were gradually employed for the interior decoration of houses, for columns, dados, and friezes. Lucius Crassus, the consul (176 b.c.), was the first so to adorn his house, and Lucullus (151 b.c.) paved his hall with black marble. Later, entire rooms were lined with thin slabs clamped to the concrete wall with iron. Sometimes such marble walls were given a thin coat of stucco and painted. As the passion for sumptuous interiors grew all the decorative arts were put into requisition. Walls were painted in fresco, as we can still see at Pompeii and in the house of Germanicus on the Palatine. Ceilings, walls, and cornices were ornamented in stucco in shallow relief. An extremely hard stucco was made with lime and powdered marble—it was nearly as durable as marble and could take almost as high a polish. It was even used for floors; for internal decoration, plaster of Paris was mixed with it. Mouldings, figures, arabesques, groups and scenes were worked in this stucco and delicately coloured. Examples have been preserved in the Diocletian museum and can be seen in situ in the Latin tombs.