Ilmen

Ilmen (Q, pron. [ˈilmen]), also known as Tar-menel, Tinwë-mallë,The History of Middle-earth, Vol. IV: The Shaping of Middle-earth, chapter V: "The Ambarkanta", pgs. 240-1, 242-3, 253 and Elenarda, was a part of the atmosphere surrounding the world of Arda before the cataclysm at the end of the Second Age. Ilmen formed the outer layer of normal air; unlike Vaiya, it only existed above Arda itself. Below Ilmen was the inner air, Vista. The stars were found in this region.The Silmarillion, "Index of Names"The Silmarillion, "Akallabêth: The Downfall of Númenor"
The air of Ilmen was breathed by the Valar in Aman and was cleansed and purified by the Light of Valinor to prevent it from being darkened with shadows.
The water of Middle-earth was formed from a compound of Vaiya and Ilmen, which was blended by Ulmo beneath Mar-talmar of the Hidden Half of Arda.
Towards the end of the First Age, Varda granted the Moon and the Sun the ability to pass through Ilmen on its way around the world, plunging down the Chasm of Ilmen on its way back.The Silmarillion, Quenta Silmarillion, Chapter XI: "Of the Sun and Moon and the Hiding of Valinor"
Sometime later, some spirits of shadow were sent against Tilion by Morgoth, but were defeated beneath the stars after a great battle.
After the Númenórean Catastrophe and the Changing of the World, the Straight Road became the only way to reach Tol Eressëa and Valinor because it passes through Ilmen. Aman is located there still.
==Etymology==
Ilmen is a Quenya name that Christopher Tolkien had said contains the stem ilm-, which may be related to the ilma ("starlight") in such words as Ilmarë and Ilmarin.The Silmarillion, "Appendix: Elements in Quenya and Sindarin Names", entry ilm-
In The Etymologies, Ilmen is related to the root GIL, which referred to "the region above air where stars are".The History of Middle-earth, Vol V: The Lost Road and Other Writings, Part Three: "The Etymologies", entry "GIL"
==Other versions==
In the I Vene Kemen, an early schematic diagram of Arda, Ilmen was referred to as Ilwe.
In the Ambarkanta, Ilwe was changed to Silma which in turn became Ilma before Tolkien wrote Ilmen as the final form.
==References==
Category:Quenya names & words
Category:Atmosphere
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