been still more the case when the stage-buildings were standing. Probably therefore, in spite of the vast numbers of the audience, the persons in the back rows could hear the words spoken in the orchestra and upon the stage much more clearly than might at first have been supposed. Another point mentioned by Vitruvius in connexion with the theatre is the advantage of erecting porticoes in the rear of the stage-buildings, to serve as a shelter for the people in case of a sudden shower of rain, and also for the convenience of the choregi. He adds that at Athens there were three buildings close to the theatre, which served admirably for this purpose. These were the Odeion, the temple of Dionysus, and the Portico of Eumenes.[541] The Odeion here referred to was that built by Pericles, which probably stood on the eastern side of the theatre, though its exact site has not yet been determined with certainty.[542] The temple of Dionysus mentioned by Vitruvius is apparently the older of the two temples, marked _t_ in the plan, and lying to the south-west of the stage-buildings. The Portico of Eumenes is supposed to have been built by Eumenes II, in the beginning of the second century, and it is thought that traces of it are to be found stretching westwards from the theatre.[543] Immediately to the south of the stage-buildings are the foundations of a long rectangular erection, belonging to the same date as the stage-buildings themselves, and marked _s_ in the plan. This erection was no doubt a portico, built in the fourth century for the purpose described by Vitruvius. In the theatre itself there was no protection for the general mass of the people either from the sun or from the rain. The huge canvas awnings, suspended upon masts, which the Latin writers refer to, were an invention of the Italians, and were only adopted in Greek theatres at a very late period.[544]