To include the Gymnasium in the same building, Nero made a wooden floor over the reservoir, which he could remove and replace at pleasure; this was covered with sand for the athletes to wrestle upon, and became the Arena. Around this great oval basin galleries were erected for the spectators, which were gradually enlarged and raised higher as the seats were further off; and the great stone arcades of the Flavian Emperors, with the corridors in them, are built round those older galleries, which were chiefly faced with brick. Several of the arches of the galleries, in the fine brickwork of Nero, remain in the Colosseum[48]; and the stone arcades were evidently built up against them without any junction between the two in any part. The bricks on the side of the arch next the stone piers of the corridors, are in many places cut in half, to make way for the stone piers. The straight vertical joints between the brick galleries and the stone arcades are often two or three inches wide; this may be the effect of an earthquake, but there is no bonding between one and the other. The enormous arcades and corridors are in themselves a gigantic work, and it was evidently difficult to obtain so great a supply of materials.

The external wall and corridor are of three periods. The first is the ground floor only, with the Doric order of columns; the first and second floor, with the Corinthian columns, belong to the second period, and it is a little later than the lowest part, but not with any long interval; the upper floor is an addition of the third century, and replaces a wooden storey.

In the interior of the building, as we are told in the anonymous chronicle published by Eccard, which is good authority[49], Vespasian dedicated the three lower steps, and Titus added two others to the three placed by his father. The wooden gallery, built upon the top of the great corridors or arcades (for the plebs), appears to have been an afterthought, not part of the original design, but an addition obviously called for. The large space at that height gave accommodation for an enormous number of people, which could not have been given before, to see what was going on upon the Arena or Stage during the performance. This had numerous trap-doors in it, under which were lifts for the wild beasts in their cages to be sent up on to the stage when wanted. The performance was in many respects like our pantomimes. There are evident traces of the lifts below, by the vertical grooves in the tufa walls for them to slide up and down[50]; and recesses remain in these walls for the counter-weights also to work in, with holes in the pavement for the sockets of pivots for the capstans necessary to wind up the cords, and loose them as required. These original walls, with the grooves for the old machines, are in many parts interfered with by more modern walls built up between them, probably in the fifth and sixth centuries, when great repairs were made after earthquakes, or perhaps rendered necessary by the weight of the water under the wooden floor in the central part.

Two important inscriptions relating to the history of the building have been preserved[51]: one found in 1810 on the western side, recording the repairs after an earthquake by the præfect Basilius, A.D. 445; the other in 1813, recording similar repairs by Lampadius, A.D. 508. Three of the marble seats were also brought to light, one with the number XVIII., another with the word EQUITI, the third, with an inscription, the beginning of which is broken off:—

tr IB IN . THEATR . LEGE . PL . VI
vind ICET . P . X . II.

This is important, because it shews the use of the word Theatrum[52], and not Amphitheatrum, for the colossal building; which agrees with the usage of Dio and other contemporary authors, who always call it Theatrum par eminence, or the great theatre of Rome, there being no need to distinguish it further.

The following extracts from Dio Cassius can only apply to the great amphitheatre:—

“Such was the shamelessness of Nero, that he himself drove chariots in public; and, sometimes, having slain wild beasts, and having suddenly introduced water into the area, he made a naval battle; and then withdrawing the water, he introduced the gladiatorial strife. Then again introducing it, he gave in public a sumptuous supper. Tigellinus was the prefect (or overseer) of the supper, and it was a supper of the grandest magnificence, arranged in this manner. In the middle of the amphitheatre and in the water great wooden wine-casks were placed, and upon them a floor of planks[53] was laid, and around this, booths and small chambers were erected[54].”

“Nero had various kinds of shows in the amphitheatre, sometimes filling it with sea-water, in which fishes and sea monsters swam, and made a naval fight between the Persians and the Athenians; then suddenly withdrawing the water, and drying the ground, he ordered a number of men on foot to rush in, not singly, but in numbers and close together[55].”

“When he (Titus) dedicated the theatre for hunting, and the thermæ called after him, he exhibited many wonderful things. Cranes fought and four elephants, nine thousand wild boars and other beasts were killed, which women, even some of noble rank, had brought together. Many contests, also, on foot, and naval fights took place, for suddenly filling the amphitheatre with water, he introduced horses and bulls, and other tame animals, who had been taught to act in the water as on land. He also introduced men in ships, who, in the guise of Corcyrians and Corinthians, imitated a naval battle[56].”