<P> Gaily bedight, A gallant knight, In sunshine and in shadow, Had journeyed long, Singing a song, In search of Eldorado . But he grew old--This knight so bold--And o'er his heart a shadow Fell as he found No spot of ground That looked like Eldorado . And, as his strength Failed him at length, He met a pilgrim shadow--"Shadow," said he, "Where can it be--This land of Eldorado?" "Over the Mountains Of the Moon, Down the Valley of the Shadow, Ride, boldly ride," The shade replied--"If you seek for Eldorado!" </P> <P> "Eldorado" is a poem written by Edgar Allan Poe, first published in April 1849 . </P> <P> The poem describes the journey of a "gallant knight" in search of the legendary El Dorado . The knight spends much of his life on this quest . In his old age, he finally meets a "pilgrim shadow" who points the way through "the Valley of Shadow". It was first published in the April 21, 1849, issue of the Boston - based The Flag of Our Union . </P>

What does the language describing the land as a long black shadow on the sea express