In Greek mythology, Augeas (also Augeias), whose name means "bright," was a king of Elis best known for his stables, which held the greatest number of cattle in the land and had never been cleaned. Cleansing them in a single day became the fifth Labour of Heracles, who succeeded by rerouting two rivers through them. Some authors number Augeas among the Argonauts. From his fouled stables the adjective "augean" came to denote a daunting task of cleaning or reform.
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I.Family
Augeas's lineage varies across the ancient sources. He was said to be either the son of Helios (by Nausidame or by Iphiboe), or of Eleios, or of Poseidon, or of Phorbas and Hyrmine. In the last account, Augeas was probably the brother of Actor, Tiphys, and Diogeneia.
His children were named as Epicaste, Phyleus, Agamede, Agasthenes, Eurytus, and Ambracia. Ancient authors set out these relationships differently, and comparative accounts of his parentage and offspring diverge from source to source.
II.Mythology
The fifth Labour of Heracles was to clean the Augean stables. Eurystheus intended the assignment to be both humiliating and impossible, since the livestock were divinely healthy and therefore produced an enormous quantity of dung. Three thousand cattle were said to live in the stables, which had not been cleaned in over thirty years. Heracles nonetheless succeeded by rerouting the rivers Alpheus and Peneus to wash out the filth.
Augeas reacted angrily, for he had promised Heracles a tenth of his cattle if the task were finished in a single day. He refused to honour the agreement, and Heracles killed him after the work was done. Heracles gave Augeas's kingdom to Phyleus, Augeas's son, who had been exiled for siding with Heracles against his father. According to the odes of the poet Pindar, Heracles then founded the Olympic Games.
Eurystheus discounted the success of this labour, both because the rushing waters had done the work of cleaning the stables and because Heracles had been paid for it. Eurystheus then sent Heracles on to defeat the Stymphalian Birds.
III.Etymology
According to the hellenist Gregory Nagy, the Homeric form of the name Augeias derives from a word meaning "sunlight." This etymology explains why Augeias is presented as the son of Helios in some versions of the myth. The name itself is glossed as meaning "bright," and from the proverbially filthy Augean stables the derivative adjective "augean" came to signify a challenging task, typically the improving or fixing of something in a very bad condition.