§ Of the Return of the Noldor The Silmarillion

His prayer was answered swiftly. For Manwë to whom all birds are dear, and to whom they bring news upon Taniquetil from Middle-earth, had sent forth the race of Eagles, commanding them to dwell in the crags of the North, and to keep watch upon Morgoth; for Manwë still had pity for the exiled Elves. And the Eagles brought news of much that passed in those days to the sad ears of Manwë. Now, even as Fingon bent his bow, there flew down from the high airs Thorondor, King of Eagles, mightiest of all birds that have ever been, whose outstretched wings spanned thirty fathoms; and staying Fingon's hand he took him up, and bore him to the face of the rock where Maedhros hung. But Fingon could not release the hell-wrought bond upon his wrist, nor sever it, nor draw it from the stone. Again therefore in his pain Maedhros begged that he would slay him; but Fingon cut off his hand above the wrist, and Thorondor bore them back to Mithrim.