Castor and Pollux horse breaker and the boxer / Polydeuces, my brothers" ..." – Helen, "Iliad" 3.253–255), but in the "Odyssey" they are treated as alive even though "the corn-bearing earth holds them". The author describes them as "having honour equal to gods", living on alternate days because of the intervention of Zeus. In both the "Odyssey" and in Hesiod, they are described as the sons of Tyndareus and Leda. In Pindar, Pollux is the son of Zeus while Castor is the son of the mortal Tyndareus. The theme of ambiguous parentage is not unique to Castor and Pollux; similar characterisations appear in
Leda and the Swan (Leonardo) on wood, 128 x 106 cm). In 1508 Leonardo painted a different composition of the subject. The picture known as "Leda and the Swan" depicted a nude standing Leda cuddling the swan, with the two sets of infant twins, and their huge broken egg-shells. The original of this is lost, probably deliberately destroyed, and was last recorded in the French royal Château de Fontainebleau in 1625 by Cassiano dal Pozzo: "A standing figure of Leda almost entirely naked, with the swan at her and two eggs, from whose broken shells come forth four babies, This work, although somewhat dry in