§ Of Eldamar and the Princes of the Eldalië The Silmarillion

Now Ossë followed after the host of Olwë, and when they were come to the Bay of Eldamar (which is Elvenhome) he called to them; and they knew his voice, and begged Ulmo to stay their voyage. And Ulmo granted their request, and at his bidding Ossë made fast the island and rooted it to the foundations of the sea. Ulmo did this the more readily, for he understood the hearts of the Teleri, and in the council of the Valar he had spoken against the summons, thinking that it were better for the Quendi to remain in Middle-earth. The Valar were little pleased to learn what he had done; and Finwë grieved when the Teleri came not, and yet more when he learned that Elwë was forsaken, and knew that he should not see him again, unless it were in the halls of Mandos. But the island was not moved again, and stood there alone in the Bay of Eldamar; and it was called Tol Eressëa, the Lonely Isle. There the Teleri abode as they wished under the stars of heaven, and yet within right of Aman and the deathless shore; and by that long sojourn apart in the Lonely Isle was caused the sundering of their speech from that of the Vanyar and the Noldor.