108

HISTORY OF ENGINEERING.

Book I.

the more necessary it was to deepen the area: this may be seen at Pa »stum, which alsoshows the manner of construction adopted when formed on the side of a hill; one half ofthe seats being on the natural slope, and the upper portions being raised on con-structions. This method, from its economy, was perhaps the earliest; and thus the firsttheatres, as already observed, were formed out of the sides of rocks and hills. The seats wereafterwards made with planks, and removed when the shows were concluded. This beingfound inconvenient, others were constructed in a more solid and substantial manner: manyhaving been destroyed by fire, stone was at last resorted to. The first amphitheatres atRome were temporary structures, and situated in the Champ de Mars , without the city.Statilius Taurus erected the first of stone, a.u.c. 725, which, with the Coliseum , were theonly two within the walls.

The amphitheatres of Castrenses, erected by Tiberius, on the Esquiline hill , of whichsome remains are still seen, near S. Croce in Jerusalem , was built of brick, and of theCorinthian order. Another built by Trajan , in the Campus Martius, was destroyed byAdrian.

Fig. 124. CASTRENSE.

Nothing gives us a higher notion of the knowledge possessed by the Romans in the artsof construction, than the numerous and vast remains of their amphitheatres, erected inalmost all their towns and provinces.

At Fedena, five miles from Rome , Attilus built an amphitheatre, in which, in consequenceof the foundations giving way, 25,000 persons perished.

At Placentia was one of the largest in Italy , built of timber, without the walls of thecity. At Arezzo, Florence, Fisole, Adria, Lucca, Palermo, Cassano, Minturno , Benevento,Alba, Capua, Pompeii, Puteoli, Otricoli, Catania, Agrigentum, Syracuse, Pa ?stum, Pola,Nismes, and Verona, Frejus, Arles, Autun, Saintes, Bordeaux, Orange, Narbonne , Die inDauphine, Cahors, Drenaiil on the Cher, Toulouse, Lyons, Vienne, Paris , Neri, GrandDrevant, Bruieres, Valonges, Besan<;on, Metz, Perigeaux, Nice, Doue sur lTlgers inPoictou. In Spain, at Hispalis near Seville, Tarragona, Saguntum , and many otherplaces.

At Smyrna is one of stone, in good preservation ; also at Sardis, the capital of Lydia,Jerusalem, Argos, and Melos; Udena, near Tunis , is another, very perfect and beautiful,and Constantinum, Istria, Tergeste, iEgeda, Parentium , and Pola, each had their amphi-theatre. Those of Nismes, Udena, the Coliseum , and Verona, are the most perfect thatremain.

Amphitheatre of Vespasian , called Coliseum , finished by the Emperor Titus about the /9thyear of the Christian era, is of an oval form, its diameters being 620 and 513 feet, measuredto the face of the outer wall, from which the semi-columns project. Ihe entire heightof the building is 157 feet, divided by four orders of architecture ; the upper has pilasters,the others half columns. Its entire area may be estimated at 249,804 superficial feet,or nearly six acres ; the cubical contents of the mass and void at nearly 40 , 000,000 of cubefeet. The arena, 287 feet in length, and 180 feet 3 inches in width, is an area about one-