Sanwe-Latya, or Communication of Thought among Elves and Maiar

[Palanan]

Near the end of Lord of the Rings, there is a lovely passage in which Celeborn, Galadriel, Elrond and Gandalf are communing in silence beneath the stars:

If any wanderer had chanced to pass, little would he have seen or heard, and it would have seemed to him only that he saw grey figures, carved in stone, memorials of forgotten things now lost in unpeopled lands. For they did not move or speak with mouth, looking from mind to mind, and only their shining eyes stirred and kindled as their thoughts went to and fro.

In this passage they are all close together, probably no farther apart than friends sitting around a fire. Are there passages elsewhere in the Lord of the Rings which suggest that sanwe-latya operates over longer distances? It’s implied to do so in the movies, but I’m wondering if there’s any hint of that in the books, or anywhere in Tolkien’s notes or other writings.

[LibraryOgre]

Well, counter-evidence would be Gandalf's captivity by Saruman. Mind you, Saruman might have been preventing it somehow, but that it did not function is a possible argument against it working at great distances.

[InvisibleBison]

When Frodo sits on the seat of Amon Hen while wearing the Ring and gazes upon Barad Dur, I'm pretty sure Gandalf speaks in his mind to help him escape from Sauron's gaze:

Then as a flas from some other point of power there came to [Frodo's] mind another thought: Take it off! Take it off! Fool, take it off! Take off the Ring!

For evidence that that's Gandalf and not Frodo, look to Gandalf's account of his activities after slaying the Balrog:

Very nearly [the Ring] was revealed to the Enemy, but it escaped. I had some part in that: for I sat in a high place, and I strove with the Dark Tower; and the Shadow passed.

I don't think this is an airtight case, but I find it convincing.