Arda was never flat

[Lalwendë]

Reading the quote used above brought to mind something else:

And still, if they should at the last come to the end of those lands and seas, beyond all lay the Ancient Darkness.

[Smith] stood beside the Sea of Windless Storm where the blue waves like snow-clad hills roll silently out of Unlight to the long strand, bearing the white ships that return from battles on the Dark Marches of which men know nothing.

Ever since the second quote was used in a recent thread about Smith Of Wootton Major it has stuck in my mind. It seems to me that it conjours up an idea of a flat earth. The waves don't come from over the horizon, they come from Unlight, a place of darkness which seems to be outside the world.

Now perhaps both passages use the idea of darkness to refer to the unknown, the distant, the undiscovered; this could simply be metaphor. When the Numenoreans made the discovery that the world had been altered, could it be that what they actually were experiencing was the dawn of a new knowledge? Previously they had held the world to be flat and that if they sailed far enough they would come to the end of it. Eventually they discovered that no matter how far they sailed they would come back to their starting point; this could coincide with the discovery (perhaps an awful realisation) that the world was after all round, and hence finite.

As to where the Elves go when they set sail, applying science to the matter doesn't answer any questions. It is possible that Valinor is a place which is difficult to locate, an anomaly; possibly it is even a place which is physically difficult to get to due to ocean currents (I often think of great feats of exploration when I consider this, such as the struggle to find the North West Passage). Another possibility is that it simply does not exist at all, that the Elves are going nowhere, a dark thought which has crossed my mind a few times; I wonder whether anyone else, with their modern logic has ever pondered this sad thought?

So choosing not to use science to answer that one is likely the only way forward. Using what is known in Tolkien's work would give the most probable answer.