The old substructures were evidently retained and used when the upper part was built 39 Piers of travertine run from top to bottom of the building to carry the upper gallery, and the old tufa walls were cut through _ib._ THE EVIDENCE OF THE CONSTRUCTION, AND COMPARISON 40-54 Comparison one of the first principles of Archæology, especially useful for this enormous amphitheatre 40 AMPHITHEATRE AT CAPUA is almost the same size as that of Rome 40, 41 XXVII. —— The substructures more perfect than in Rome 41 —— Aqueduct and drain _ib._ XXVIII. —— Dens under the _podium_ _ib._ —— Sockets for the pivots for the cages _ib._ XXIX. —— Arena of brick, not wood, but had apertures for the trap-doors _ib._ XXX. —— Grooves for covers over them to make them water-tight _ib._ —— The building is of the time of Hadrian 40 —— Inscription 41, 42 —— PUTEOLI, OR POZZUOLI 42, 43 XXXII. —— Building much smaller than those of Rome or Capua 42 —— Substructures more perfect and more highly finished _ib._ —— Arena of brick, with apertures for trap-doors _ib._ —— Arrangement for fixing the masts or poles for the awning, as in Rome 43 XXXIII. Amphitheatre at Puteoli, or Pozzuoli—The building also of the time of Hadrian _ib._ XXXIV. —— The vaults preserved and used 42 —— VERONA 43, 44 XXXI., XXXII. —— —— The outer wall almost destroyed 43 —— —— Arcade of two lower storeys preserved 44 —— —— Comparison of the number that each amphitheatre would contain _ib._ —— —— The seats remarkably well preserved _ib._ —— —— Dimensions of all the three principal amphitheatres at Rome, Verona, Capua 45 —— POLA, IN ISTRIA 45, 46 —— —— Built in white stone, like marble _ib._ —— —— Two tiers of arches remain _ib._ —— —— And a curious stone parapet, with indications of the awning _ib._ —— —— Built against a rocky mountain on the slope _ib._ —— —— Substructures in the lower part _ib._ —— —— Canal for water visible _ib._