Circular temples were an elegant variety, which seems to have been originated by the Romans, and of which two well-known examples remain—the Temples of Vesta at Rome and at Tivoli. The columns of the temple at Tivoli (Fig. [128]) form a well-known and pleasing variety of the Corinthian order, and the circular form of the building as shown on the plan (Fig. [127]) gives excellent opportunities for good decorative treatment, as may be judged of by the enlarged diagram of part of the peristyle (Fig. [129]).

Basilicas.

Among the most remarkable of the public buildings of Roman times, both in the mother-city and in the provinces, were the Basilicas or Halls of Justice, which were also used as commercial exchanges. It is also believed that Basilicas existed in some Greek cities, but no clue to their structural arrangements exists, and whence originated the idea of the plan of these buildings we are unable to state; their striking similarity to some of the rock-cut halls or temples of India has been already pointed out. They were generally (though not always) covered halls, oblong in shape, divided into three or five aisles by two or more rows of columns, the centre aisle being much wider than those at the sides: over the latter, galleries were frequently erected. At one end was a semicircular recess or apse, the floor of which was raised considerably above the level of the rest of the building, and here the presiding magistrate sat to hear causes tried. Four[20] of these buildings are mentioned by ancient writers as having existed in republican times, viz. the Basilica Portia, erected in B.C. 184, by Cato the Censor; the Basilica Emilia et Fulvia, erected in B.C. 179 by the censors M. Fulvius Nobilior and M. Æmilius Lepidus, and afterwards enlarged and called the Basilica Paulli; the Basilica Sempronia, erected in B.C. 169 by Tib. Sempronius Gracchus; and the Basilica Julia, erected by Julius Cæsar, B.C. 46. All these buildings had wooden roofs, and were of no great architectural merit, and they perished at a remote date. Under the Empire, basilicas of much greater size and magnificence were erected; and remains of that of Trajan, otherwise called the Basilica Ulpia, have been excavated in the Forum of Trajan. This was about 360 ft. long by 180 ft. wide, had four rows of columns inside, and it supposed to have been covered by a semicircular wooden roof. Apollodorus of Damascus was the architect of this building. Another basilica of which remains exist is that of Maxentius, which after his overthrow by Constantine in A.D. 312, was known as the Basilica Constantiniana. This structure was of stone, and had a vaulted roof; it was 195 ft. between the walls, and was divided into three aisles by piers with enormous columns standing in front of them.

Fig. 130.—Ground-plan of the Basilica Ulpia, Rome.

One provincial basilica, that at Trèves, still stands; and although it must have been considerably altered, it is by far the best existing example of this kind of building. The internal columns do not exist here, and it is simply a rectangular hall about 175 ft. by 85 ft., with the usual semicircular apse.

The chief interest attaching to these basilicas lies in the fact that they formed the first places of Christian assembly, and that they served as the model upon which the first Christian churches were built.

Theatres and Amphitheatres.

Although dramas and other plays were performed in Rome as early as 240 B.C., there seems to have been a strong prejudice against permanent buildings for their representation, as it is recorded that a decree was passed in B.C. 154 forbidding the construction of such buildings. Mummius, the conqueror of Corinth, obtained permission to erect a wooden theatre for the performance of dramas as one of the shows of his triumph, and after this many buildings of the kind were erected, but all of a temporary nature; and it was not till B.C. 61 that the first permanent theatre was built by Pompey. This, and the theatres of Balbus and Marcellus, appear to have been the only permanent theatres that were erected in Imperial Rome; and there are no remains of any but the last of these, and this is much altered. So that, were it not for the remains of theatres found at Pompeii, it would be almost impossible to tell how they were arranged; but from these we can see that the stage was raised and separated from the part appropriated to the spectators by a semicircular area, much like that which in Greek theatres was allotted to the chorus: in the Roman ones this was assigned for the use of the senators. The portion devoted to the spectators—called the Cavea—was also semicircular on plan, and consisted of tiers of steps rising one above the other, and divided at intervals by wide passages and converging staircases communicating with the porticoes, which ran round the whole theatre at every story.