In Appendix F of "The Lord of the Rings", the name Sméagol is said to be a "translation" of the Middle-earth name "Trahald" (having to do with the idea of "burrowing", and rendered with a name based on Old English "smygel" of similar meaning). Several critics speculate that "Beowulf" Grendel could have been an inspiration for Gollum due to the many parallels between them—such as their affinity for water, their isolation from society, and their bestial description. Tolkien accredited "Beowulf" as one of his "most valued sources" when writing "The Hobbit". The rhyming name of his relative "Déagol" is from Old English "dēagol", meaning "secretive, hidden". In Tolkien's "Red Book of Westmarch", the name "Déagol" is supposedly a translation of the "original" name in the author-invented language of Westron, "Nahald", with the same meaning. Gollum was introduced in "The Hobbit" as "a small, slimy creature" who lived on a small island in an underground lake at the roots of the Misty Mountains. He survived on cave fish, which he caught from a small boat, and small goblins who strayed too far from the stronghold of the Great Goblin. Over the years, his eyes adapted to the dark and became "lamp-like", shining with a sickly pale light. Bilbo Baggins stumbled upon Gollum's lair, having found the Ring in the network of goblin tunnels leading down to the lake. At his wits' end in the dark, Bilbo agreed to a riddle game with Gollum on the chance of being shown the way out of the mountains. In the first edition of "The Hobbit", Gollum's size is not stated. Originally, he was also characterised as being less bound to the Ring than in later versions; he offered to give the Ring to Bilbo if he lost the riddle game, and he showed Bilbo the way out of the mountains after losing. To fit the concept of the ruling Ring that emerged during the writing of "The Lord of the Rings", Tolkien revised later editions of "The Hobbit". The version of the story given in the first edition became the lie that Bilbo made up to justify his possession of the Ring to the Dwarves and Gandalf. In the new version, Gollum pretended that he would show Bilbo the way out if he lost the riddle-game, but he actually planned to use the Ring to kill and eat the hobbit.