Myth
Perseus delivering Andromeda from the sea monster, Corinthian vase, Altes Museum in Berlin
Cassiopeia, having proclaimed that his daughter (or according to other versions of itself) was equal to the beauty of the Nereids , had incurred the wrath of Poseidon , to avenge that caused flooding and sent a sea monster ( whale Cetus ) which began to destroy men and cattle.
The oracle of Ammon revealed no respite would be possible as the king will not deliver his daughter to the monster. It was then attached to a naked rock on the coast. Perseus , returning from his victory over the Gorgon Medusa , found Andromeda, slew the monster and freed the girl. Ovid says that algae solidified by the venom of snakes Medusa instituted property rigidifying marine coral, when it comes into contact with air.
Perseus married Andromeda though she was promised to Phineus , the brother of Cepheus. At the wedding a quarrel took place between the two suitors and in turn Phineus was turned to stone by the Gorgon's head.
Andromeda followed her husband to Tiryns in Argolis and became the ancestor of the family of the Perseids through his son Perses. Perseus and Andromeda had six son: Perses, Alcaeus , Hlos , Mestor , Sthenelus and Electryon , and a daughter: Gorgophone. Their descendants ruled the Mycenae Electryon up to Eurystheus , whom Atreus got the kingdom, and the great hero Hercules is part of that descent.
After his death, Andromeda was placed by Athena amongst the constellations , near Perseus and Cassiopeia.
Sophocles and Euripides , and in more modern times, Corneille , wrote the story of his tragedy and his misfortune is the subject of many ancient works of art.
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