=Olym´pus.= A mountain in Macedonia and Thessaly. The ancients supposed that it touched the heavens, and thus they have made it the residence of the gods, and the place where Jupiter held his court. On the top of the mountain, according to the poets, eternal spring reigned. =Om´phale.= A queen of Lydia, daughter of Jardanus. She married Tmolus, who at his death left her mistress of his kingdom. She had heard of the exploits of Hercules, and wished to see him. After he had slain Eurytus, Hercules was ordered to be sold as a slave, and was purchased by Omphale, who gave him his liberty. He became in love with Omphale, who reciprocated his passion. He is represented by the poets as being so infatuated with her that he sat spinning by her side surrounded by her women, whilst she garbed herself with his lion's skin, arming herself with his club. =Oppia´nus.= A Greek poet of Cilicia. He wrote some poems celebrated for their sublimity and elegance. Caracalla gave him a piece of gold for every verse in one of his poems. Oppian died of the plague in the thirtieth year of his age. =Ops.= A daughter of Coelus and Terra, the same as the Rhea of the Greeks, who married Saturn, and became mother of Jupiter. She was known amongst the ancients by the different names of Cybele, Bona Dea, Magna Mater, Thya, Tellus, and Proserpina. =Ores´tes.= A son of Agamemnon and Clytemnestra. His father was slain by Clytemnestra and Ægisthus, but young Orestes was saved from his mother's dagger by his sister Electra, called by Homer Laodicea, and was conveyed to the house of Strophius, king of Phocis, who had married a sister of Agamemnon. He was indulgently treated by Strophius, who educated him with his son Pylades. The two young princes formed the most inviolable friendship. When Orestes had arrived at years of manhood he avenged his father's death by killing his mother Clytemnestra. =Or´igen.= A Greek writer, celebrated for his learning and the sublimity of his genius. He suffered martyrdom in his sixty-ninth year. His works are numerous, consisting of commentaries on the Scriptures and various treatises.