The use of marble as a means of decoration was not always customary with the Romans, and was introduced by L. Crassus, the censor, who had his house decorated with six small columns of marble from Hymettus, and was very much blamed for this extravagance. M. Scaurus, the ædile, who built the famous wooden theatre, decorated with 360 pillars of marble, glass, and bronze, and about 3,000 statues and images, had the atrium and peristyle of his private house richly adorned with exquisite columns. Manurra, prefect of the armourers, under Julius Cæsar in Gaul, is set down as the first who had his walls decorated with marble incrustations; whilst M. Catulus could boast of the first marble flooring, and of thresholds in Numidian marble. Of temples, one of the first constructed of marble blocks in a purer Greek style was that of Jupiter Tonans. The temple of _Fortuna Virilis_ which rose on a lofty substructure on the banks of the Tiber, was in the Ionic style. The Vesta temple at Tivoli, enthroned on a steep and rocky height above the foaming waters of the Anio, was a circular building in the Korinthian style. Theatres, public halls, baths, and Fora were found necessary, either to distract the public mind from political matters, or to gain the suffrages of the fickle mob, eager for amusement and excitement. The first theatre in stone was erected by Pompey. Julius Cæsar surpassed all his predecessors and rivals in magnificence. He began the theatre of Marcellus, which was completed by Augustus, and so enlarged and beautified the _Circus Maximus_ that it could accommodate 150,000 spectators; he built the beautiful Basilica Julia, a public law-court for the Centumviri or Judges to sit in, and hear causes, and for the counsellors to receive their clients, and had a new Forum constructed, and adorned it with a temple dedicated to Venus Genetrix. The Roman Forum (in imitation of the Greek Agora) was a building about three times as long as broad. The interior was surrounded by arched porticos, and flanked by the most stately edifices, such as theatres, basilicæ, and temples.