He eventually stumbled upon a small ring, but thought nothing of it, and put it in his back pocket.
Frodo is an extraordinary Hobbit, that's for sure. When they arrive in Rivendell and stay two weeks there, Bilbo is happy about him having left his home for the first time.
Bilbo is also fastidious: He does not like the mess the dwarves create in his home and, although he has been invited by Gandalf to join a dramatic adventure, in Chapter 2 he almost returns home because he has forgotten his handkerchiefs and his pipe.
It defines who we are and who we choose to be and how we are thought of by others we deal with. Gollum led Bilbo to the eastern door of the goblin-tunnels, through which Bilbo departed in safety. That shows plainly how Bilbo has changed since the beginning.
While crossing the river, Bombur fell in.