In addition to the scenery in the background, the stage was of course decorated with such objects and properties as were required by the particular play. Aeschylus is said to have been the first to adorn the stage in this manner.[614] If the scene was a palace or temple, statues of the gods were generally placed in front of it, and are frequently referred to in the course of the drama. For instance, there was the statue of Athene in front of her temple in the Eumenides, and the statues of the tutelary deities before the palace of the Atreidae in the Electra of Sophocles. In the Hippolytus there were two statues in front of the palace of Theseus, one of Artemis the huntress, and the other of Cypris, the goddess of love. When Hippolytus returns from the hunt, he offers a garland of flowers to the statue of Artemis, but refuses to pay any homage to the statue of Cypris, in spite of the remonstrances of his attendant. Again, in the country region depicted in the Oedipus Coloneus the statue of the hero Colonus stood in a conspicuous position.[615] Other examples of the practice of decorating the stage with statues are often to be met with both in tragedy and in comedy. Altars, again, were very common objects upon the Greek stage. In the Supplices of Aeschylus the fugitive maidens take refuge round an altar. The Oedipus Tyrannus opens with the spectacle of a group of Thebans kneeling in supplication before the altar of Apollo.[616] Another constant feature in the stage decoration was the stone obelisk in honour of Apollo of the Highways. It was an ordinary practice among the Greeks to place such obelisks in front of their houses. Their presence upon the stage is often referred to by the dramatic poets.[617] Various other objects were occasionally required by particular plays. There was the tomb of Darius in the Persae, and the tomb of Agamemnon in the Choephori. In the Oedipus Coloneus a rocky ledge was needed for Oedipus to rest himself upon. In the Acharnians and the Knights a few benches must have been erected upon the stage to serve as a rude imitation of the Pnyx. Walls, watch-towers, and beacon-towers are mentioned by Pollux; and the presence of other similar decorations and erections can be inferred from the extant tragedies and comedies.[618]