2 Some action: encounter with trolls (adds little to the overall story)

3 Rest and some information to achieve the goal is acquired (nothing very important)

14 The main antagonist is killed, but more trouble follows

15 Buildup to the second climax

The stage is set. The protagonist is introduced and he is told his goal - the quest for treasure.
The goal of the novel is established in the very first chapter.
We are also introduced to the most important characters in this chapter.

Chapter 2:

Just a small skirmish that adds little to the story, except for the only fact that the protagonist and his team acquire some weapons which comes in handy later. They also acquire some treasure which is nothing compared to the final goal.

Chapter 3:
A short rest and some intel on acquiring the treasure.

Chapter 4:
A mini battle takes place which sets the ball rolling for the final battle(unknown to the reader at this time).

Chapter 5:
A very important object is acquired by the main character which decides the fate of this whole story. This event changes the hero.

Chapter 6:
The situation is further escalated with more action as the enemies follow up. But they are repeatedly defeated for a second time and the hero/hero's team gets a new ally: The Eagles.

Chapter 7:
A short rest and again the team is reinforced with a new ally: Beorn.
But they also lose an important friend temporarily in this chapter: Gandalf.

Chapter 8:
An ordeal and a challenge (spider attack). Most of the team is imprisoned by the Wood-Elves.
Until Chapter 7, the team was going through an adventure. But in this chapter, the adventure turns into an ordeal.

Chapter 9:
The ordeal continues. But the hero hatches a plan to save his team and the plan itself is an ordeal. But it works.

Chapter 10:
A short rest

Chapter 11:
The buildup towards the climax begins from this chapter. They reach the Mountain guarded by the dragon and search for a way in using their map.

Chapter 12:
The hero is sent on a reconnaissance mission. He succeeds and find's the enemy's weakest point. The dragon then flies to Lake-town.

Chapter 13:
Adds little to the story except for the fact that Bilbo pockets the Arkenstone, which is very important to Thorin. The plot surrounding this stone is itself not very important and it adds very little to the overall story. Towards the end, Bilbo tries to use this precious stone to stop the battle, but the battle takes place anyway. So the author has used Arkenstone only for two purposes:

1. Thorin, in his deathbed, speaks philosophy: says that the world would be a better place if everyone behaves like hobbits who value food, friends, and music above things like treasure; a moral is conveyed.

2. Bilbo becomes a great friend of wood-elves and Bard because of this stone.
What the Arkenstone really does is that it adds value to the Hero's character.

Chapter 14:
This is a little flashback into Chapter 12. The dragon after flying to Lake-town had been killed by Bard. The dwarves and Bilbo learn this important piece of news in this chapter.
But trouble brews up for the dwarves as the Elven King sends an army to acquire the treasure.

So chapters 11, 12, 13 and, 14 constitute a mini climax. Until now the readers are made to believe that succeeding the dragon to get the treasure to be the main goal. But now we have a little subplot and we need another climax.

Chapter 15:
The stage is set for a battle between elves and men on one side against the dwarves.

Chapter 16:
The Arkenstone story discussed previously. It adds nothing to the overall story other than enhancing the image of our hero - Bilbo Baggins.

Chapter 17:
This is the climax chapter.
A twist in the tale: just when we think that the battle is about to begin a new common enemy enters. The battle does happen, but the dwarves, men, and elves together fight against the goblins.

Chapter 18:
Our hero's return journey commences with some rest in the middle.

Chapter 19:
The journey continues and Bilbo reaches the Shire. All is well.

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