Somewhere beneath the seats of the spectators, a flight of stairs was constructed, which was called the Charonic, and by which, unseen by the audience, the shadows of the departed, ascended into the orchestra, and thence to the stage. The furthermost brink of the logeum must sometimes have represented the sea shore. Moreover the Greeks in general skilfully availed themselves even of extra-scenic matters, and made them subservient to the stage effect. Thus, I doubt not, but that in the _Eumenides_ the spectators were twice addressed as an assembled people; first, as the Greeks invited by the Pythoness to consult the oracle; and a second time as the Athenian multitude, when Pallas, by the herald, commands silence during the trial about to commence. So too the frequent appeals to heaven were undoubtedly addressed to the real heaven; and when Electra on her first appearance exclaims: "O holy light, and thou air co-expansive with earth!" she probably turned towards the actual sun ascending in the heavens. The whole of this procedure is highly deserving of praise; and though modern critics have censured the mixture of reality and imitation, as destructive of theatrical illusion, this only proves that they have misunderstood the essence of the illusion which a work of art aims at producing. If we are to be truly deceived by a picture, that is, if we are to believe in the reality of the object which we see, we must not perceive its limits, but look at it through an opening; the frame at once declares it for a picture. Now in stage-scenery we cannot avoid the use of architectural contrivances, productive of the same effect on dramatic representation as frames on pictures. It is consequently much better not to attempt to disguise this fact, but leaving this kind of illusion for those cases where it can be advantageously employed, to take it as a permitted licence occasionally to step out of the limits of mere scenic decoration. It was, generally speaking, a principle of the Greeks, with respect to stage imitation, either to require a perfect representation, and where this could not be accomplished, to be satisfied with merely symbolical allusions. The machinery for the descent of gods through the air, or the withdrawing of men from the earth, was placed aloft behind the walls of the two sides of the scene, and consequently removed from the sight of the spectators. Even in the time of Aeschylus, great use was already made of it, as in the _Prometheus_ he not only brings Oceanus through the air on a griffin, but also in a winged chariot introduces the whole choir of ocean nymphs, at least fifteen in number. There were also hollow places beneath the stage into which, when necessary, the personages could disappear, and contrivances for thunder and lightning, for the apparent fall or burning of a house, &c.