Originally Posted by Lost in Space
Please PM me with any questions you may have. It would seem that your reading of the text is somewhat confused as it were and I'd really like to clarify some things for you in private.
I'm not going to spoil that part of the book or get into that, but there was definitely no confusion here. I distinctly see a large Gold/Silver Key being mentioned, that the trolls
carried on their person plus the puzzle Bilbo had to solve for it. It was absolutely not a cave. It was a very large stone door he could only open using a key the troll dropped, and it was a huge dungeon like area with brass buttons. You could see skeletons, so there is no way to reconcile it as just a cave. This was a fairly large cavern with a door.
Plus the following text comes below the spoiler that's in the book.
“What are moon-letters?” asked the hobbit full of excitement. He loved maps, as I have told you before; and he also liked runes and letters and cunning handwriting, though when he wrote himself it was a bit thin and spidery.
“Moon-letters are rune-letters, but you cannot see them,” said Elrond, “not when you look straight at them. They can only be seen when the moon shines behind them, and what is more, with the more cunning sort it must be a moon of the same shape and season as the day when they were written. The dwarves invented them and wrote them with silver pens, as your friends could tell you. These must have been written on a midsummer’s eve in a crescent moon, a long while ago.”
“What do they say?” asked Gandalf and Thorin together, a bit vexed perhaps that even Elrond should have found this out first, though really there had not been a chance before, and there would not have been another until goodness knows when.
“Stand by the grey stone when the thrush knocks,” read Elrond, “and the setting sun with the last light of Durin’s Day will shine upon the key-hole.”
“Durin, Durin!” said Thorin. “He was the father of the fathers of the eldest race of Dwarves, the Longbeards, and my first ancestor: I am his heir.”
“Then what is Durin’s Day?” asked Elrond.
“The first day of the dwarves’ New Year,” said Thorin, “is as all should know the first day of the last moon of Autumn on the threshold of Winter. We still call it Durin’s Day when the last moon of Autumn and the sun are in the sky together. But this will not help us much, I fear, for it passes our skill in these days to guess when such a time will come again.”
A very specific puzzle related to Durin's day is elaborated upon in the novel. The whole group actually has quite a few excursions up the river, which involve crossing large water areas and even a swamp that will swallow your horse...before
they even arrive in Rivendell. What was most surprising for me is Thorin specifically remembers the runes, and even retells a story of his father/family traveling into Smaug's cavern many years ago in a quest for a weapon. This should have created the perfect flashback scene to show the story and show Bilbo, but what is most surprising to me is all of it was omitted. Even the runes and the five foot four riddle.
I would have very much liked the Thorin story myself. Instead as replacement of all those things, is a sub-plot about a Necromancer and Radagast which nobody would recognize unless they read the LOTR appendices which are quite long. I'm not saying I dislike the sub-plots, but this came out of left field and was a night/day difference from what occurs in their novel.