The construction consists for the most part of the rough masonry called opus incertum, with quoins of squared stone, and some trifling restorations of rubble. This rude mass was probably once covered with a more sumptuous facing of hewn stone: but there are now no other traces of it than a few of the key-stones, on one of which a chariot and two horses is sculptured, on another a head; besides which there are a few stars on the wedge-stones.

At each end of the ellipse were entrances into the arena for the combatants, through which the dead bodies were dragged out into the spoliarium. These were also the principal approaches to the lower ranges of seats, occupied by the senators, magistrates, and knights, by means of corridors to the right and left which ran round the arena. The ends of these passages were secured by metal gratings against the intrusion of wild beasts. In the northern one are nine places for pedestals to form a line of separation, dividing the entrance into two parts of unequal breadth. The seats are elevated above the arena upon a high podium or parapet, upon which, when the building was first opened, there remained several inscriptions, containing the names of duumvirs who had presided upon different occasions. There were also paintings in fresco, one representing a tigress fighting with a wild boar; another, a stag chased by a lioness; another, a battle between a bull and bear. Other subjects comprised candelabra, a distribution of palms among the gladiators, winged genii, minstrels, and musicians; but all disappeared soon after their exposure to the atmosphere. The amphitheatre comprises twenty-four rows of seats, and about 20,000 feet of sitting-room.

It may be observed that the arena of the amphitheatre of Pompeii appears to be formed of the natural surface of the earth, and has none of those vast substructions observable at Pozzuoli and Capua. It does not, therefore, appear capable of being turned into a Naumachia, nor indeed would it have been easy to find there water enough for such a purpose.

In the Roman theatre the construction of the orchestra and stage was different from that of the Greeks. By the construction peculiar to the Roman theatre, the stage was brought nearer to the audience (the arc not exceeding a semi-circle), and made considerably deeper than in the Greek theatre. The length of the stage was twice the diameter of the orchestra. The Roman orchestra contained no thymele. The back of the stage, or proscenium, was adorned with niches, and columns, and friezes of great richness, as may be seen in some of the theatres of Asia Minor, and in the larger theatre at Pompeii, which belong to the Roman period.

On the whole, however, the construction of a Roman theatre resembled that of a Greek one. The Senate, and other distinguished persons, occupied circular ranges of seats within the orchestra; the prætor had a somewhat higher seat. The space between the orchestra and the first præcinctio, usually consisting of fourteen seats, was reserved for the equestrian order, tribunes, etc. Above them were the seats of the plebeians. Soldiers were separated from the citizens. Women were appointed by Augustus to sit in the portico, which encompassed the whole. Behind the scenes were the postscenium, or retiring-room, and porticoes, to which, in case of sudden showers, the people retreated from the theatre.

The earliest theatres at Rome were temporary buildings of wood. A magnificent wooden theatre, built by M. Æmilius Scaurus, in his edileship, B.C. 58, is described by Pliny. In 55 B.C., Cn. Pompey built the first stone theatre at Rome, near the Campus Martius. A temple of Venus Victrix, to whom he dedicated the whole building, was erected at the highest part of the cavea.

The next permanent theatre was built by Augustus, and named after his favorite, the young Marcellus, son of his sister Octavia. Vitruvius is generally reported to have been the architect of this building, which would contain 30,000 persons. The audience part was a semi-circle 410 feet in diameter. Twelve arches of its external wall still remain. From marks still visible in the large theatre at Pompeii, the place reserved for each spectator was about 13 inches. This theatre contained 5,000. The theatre of Pompeii, at Rome, contained 40,000. The theatre of Scaurus is said to have contained 80,000. The Romans surpassed the Greeks in the grandeur and magnificence of these buildings. They built them in almost all their towns. Remains of them are found in almost every country where the Romans carried their rule. One of the most striking Roman provincial theatres is that of Orange, in the south of France.

Odeum was a building intended for the recitations of rhapsodists and the performances of citharædists, before the theatre was in existence. In its general form and arrangements the odeum was very similar to the theatre. There were, however, some characteristic differences. The odeum was much smaller than the theatre, and it was roofed over. The ancient and original Odeum of Athens in the Agora was probably erected in the time of Hipparchus, who, according to Plato, first introduced at Athens the poems of Homer, and caused rhapsodists to recite them during the Panathenæa. There were two others in Athens—the Odeum of Pericles, and that of Herodes Atticus. The Odeum of Pericles was built in imitation of the tent of Xerxes. It was burnt by Sylla, but was restored in exact imitation of the original building. It lay at the east side of the theatre of Dionysus. The Odeum of Herodes Atticus was built by him in memory of his departed wife Regilla, whose name it commonly bore. It lies under the southwest angle of the Acropolis. Its greatest diameter within the walls was 240 feet, and it is calculated to have held about 8,000 persons. There were odea in several of the towns of Greece, in Corinth, Patræ, and at Smyrna, Ephesus and other places of Asia Minor. There were odea also in Rome; one was built by Domitian, and a second by Trajan. There are ruins of an Odeum in the villa of Adrian, at Tivoli and at Pompeii.

Remains of amphitheatres are found in several cities of Etruria. The amphitheatre of Sutri is considered to be peculiarly Etruscan in its mode of construction. It is cut out of the tufa rock, and was no doubt used by that people for festal representations long before Rome attempted anything of the kind. The Romans copied these edifices from the Etruscans. We have historical evidence, also, that gladiatorial combats had an Etruscan origin, and were borrowed by the Romans.

Amphitheatres were peculiar to the Romans. The gladiatorial shows, and the chase and combats of wild beasts with which the amphitheatre is always connected, were at first given in the circus. Its unsuitableness for such sports determined Julius Cæsar, in his dictatorship, to construct a wooden theatre in the Campus Martius, built especially for hunting. Caius Scribonius Curio built the first amphitheatre, for the celebration of his father's funeral games. It was composed of two theatres of wood, placed on pivots, so that they could be turned round, spectators and all, and placed face to face, thus forming a double theatre, or amphitheatre, which ending suggested its elliptical shape. Statilius Taurus, the friend of Augustus, B.C. 30, erected a more durable amphitheatre, partly of stone and partly of wood, in the Campus Martius. Others were afterwards built by Caligula and Nero. The amphitheatre of Nero was of wood, and in the Campus Martius.