TWILIGHT AND DAWN FROM THE 6TH TO THE IOTH CENTURY the Roman sense of power, mass and plastic body belong to a period later than the Republic, and even the Early Empire. The Colosseum is of the late 1st century A.D., the Pantheon of the early 2nd, the Baths of Caracalla of the early 3rd, the Basilica of Maxentius (usually called of Constantine) of the early 4th. By then a fundamental change of spirit and no longer only of forms had taken place. The relative stability of the Roman Empire was overthrown after the death of Marcus Aurclius (180); rulers followed each other at a rate such as had been known only during short periods of civil war. Between Marcus Aurelius and Constantino, in 125 years, there were forty-seven emperors; less than four years was the average duration of a reign. They were no longer elected by the Roman Senate, that enlightened body of politically experienced citizens, but proclaimed by some provincial army of barbarian troops, often barbarians themselves, rude soldiers of peasant stock, ignorant of and unsympathetic to the achievements of Roman civilisation. There was constant internecine warfare, and constant attacks of barbarians from outside had to be repulsed. Cities declined and were in the end deserted, their market-halls and baths and blocks of flats collapsed. Soldiers of the Roman army sacked Roman towns. Goths, Alemans, Franks, Persians sacked whole provinces. Trade, seaborne and landbornc, came to an end, estates and farms and villages became self-supporting once again, payments in money were replaced by payments in kind; taxes were often paid in kind. The educated bourgeoisie decimated by wars, executions, murder and a lower and lower birthrate had no longer a share in public affairs. Men from Syria, Asia Minor, Egypt, from Spain, Gaul and Germany, held all the important positions. The subtle political balance of the Early Empire could no longer be appreciated and was no longer maintained. When a new stability was brought about by Diocletian and Constantino about 300, it was the stability of an oriental autocracy with a rigid oriental court ceremonial, with a merciless army and far-reaching State control. Soon Rome was no longer the capital of the Empire; Constantinople took her place. Then the Empire fell into two: that of the East to prove mighty, that of the West to become the prey of Teutonic invaders, the Visigoths, the Vandals, the Ostrogoths, the Lombards, and then for a while to be part of the Eastern—the Byzantine—Empire. Now during these centuries the massive walls, arches, vaults,