In describing the ruins of the stage-buildings in the Athenian theatre we showed that the first great alteration made in the older structure was the erection of a stone stage. This stage was about thirteen feet high, and from nine to ten feet deep, and was enclosed between shallower side-wings. The change effected at Athens is a type of similar changes which were carried out in most of the other Greek theatres with which we are acquainted. The recent excavations at Megalopolis, Delos, Eretria, and many other places, show that from the beginning of the second century onwards, and probably earlier, stone proscenia of the kind just described became a regular feature in ordinary Greek theatres.[401] Moreover there is evidence to prove that as early as the beginning of the third century proscenia made of wood, but resembling the later stone ones in height and depth, had begun to be erected in various cities. The theatre at Sicyon was built about this period, and the stage-buildings were to a large extent excavated out of the rock. The slopes which led up to the stage on each side, being cut out of the rock, still remain, and prove that the stage was about eleven feet above the level of the orchestra. The old wall which served as a foundation for the wooden proscenium is also partly preserved, and runs along the line of the later stone erection. In it are holes for the posts on which the wooden stage was supported.[402] At Eretria, again, the theatre was reconstructed about the beginning of the third century, and the orchestra was sunk about eleven feet into the rock, but the stage-buildings were left at their original level. Hence the wooden stage built in front of them must have been eleven feet high.[403] The theatre at Priene is somewhat exceptional. Here there are the remains of a proscenium belonging to the third century, but built of stone like those of later times. This, however, is the only instance yet discovered of a stone proscenium which can be ascribed with certainty to such an early period.[404] From these various indications it seems probable that the tall and narrow stage of the later type began to become general at the close of the fourth century, though at first it was usually made of wood. In the course of the second and first centuries this wooden stage was replaced in most theatres by a permanent one of stone. The evidence derived from the ruins as to the size and shape of the later stage corresponds, in most cases, with the statement of Vitruvius, the Roman architect, who wrote about the end of the first century B.C. In his account of the Greek theatre of his own time he lays it down as a rule that the proscenium should be from ten to twelve feet high, and about ten feet deep.[405] [Illustration: FIG. 8 A.]