[*Varda*]

I think one thing that this chapter had in common with the Prologue, as others have said, the emphasis is again on the hobbits.

The tone at the beginning is very lighthearted, the hobbits gossiping in the Ivy Bush, but as Squatter says, there is a tension and sense of foreboding that seems to be underlying in this chapter, which escapes the reader's notice the first time, but once you've read the whole book, and go back for a re-read, you notice Tolkien's little hints.

'His real business was far more difficult and dangerous, but the Shire-folk knew nothing about it'

To me, this is just a hint of the difficult and dangerous situations that the hobbits are soon to find themselves in, and that they are so ignorant of the outside world just makes it appear all the more dangerous.

The lighthearted tone also doesn't last all the way through this chapter, when Tolkien again drops hints of darker things to come during Gandalf and Bilbo's conversation, as Bilbo finds it so difficult to give up the ring. For those who have read the Hobbit, too, they will see the parallels between Bilbo and Gollum as Bilbo says 'My precious'.

'He took a step towards the hobbit, and he seemed to grow tall and menacing; his shadow filled the little room'

We see Gandalf as more than just a wizard who makes fireworks, as the hobbits see him, but rather as someone more powerful than the Hobbit portrayed him.

To me, the chapter seemed to get more lighthearted after Bilbo left, with some funny moments at Bilbo giving the presents away, as well as our introduction to Otho and Lobelia in person.

I think in the final lines of the chapter, the tone has changed again - Tolkien is again hinting at trouble to come. The hilarity and easygoing hobbit life, shown throughout the chapter, can't hide the shadow that is growing even in the Shire.

'He gave a final wave of his hand, and walked off at a surprising pace; but Frodo thought the old wizard looked unusually bent, almost as if he was carrying a great weight. The evening was closing in, and his cloaked figure quickly vanished into the twilight. Frodo did not see him again for a long time.'