But either in his dreams or out of them, he could not tell which, Frodo heard a sweet singing running in his mind: a song that seemed to come like a pale light behind a grey rain-curtain, and growing stronger to turn the veil all to silver and glass, until at last it was rolled back, and a far green country opened before him under a swift sunrise.

J.R.R. Tolkien (1892-1973) English writer, fabulist, philologist, academic [John Ronald Reuel Tolkien]

The Lord of the Rings, Vol. 1: The Fellowship of the Ring, Book 1, ch. 8 “Fog on the Barrow-Downs” (1954)
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