Leaves are falling all around;

Its time I be on my way.

Thanks to you I'm much obliged

For such a pleasant stay.

But now its time for me to go;

The autumn moon lights my way.

But now I smell the rain and with it pain

And its heading my way.

 
 

After confirming that Frodo's ring was indeed the One Ring, Gandalf spends part of the summer making plans for Frodo's journey to Rivendell. At the end of the Summer he sets off on an adventure of his own. By the end of that summer, Frodo leaves Hobbiton to set out on his quest as well. (The Fellowship of the Ring p. 76-77)

Mine's a tale that can't be told.

My freedom I hold dear.

How years ago in days of old

When magic filled the air.

"Twas in the Darkest depths of Mordor

I met a girl so fair,

But Gollum and the Evil One

Crept up and slipped away with her."

 

As the shadow of evil began to creep back into Mirkwood after the One Ring had been lost, the wizards - Saruman, Gandalf, and Radagast - were sent to help counter the sorcery of Sauron. [ed. There were actually two more wizards who were sent over, but were not named and headed back inland] Gandalf feared that the shadow was actually the return of Sauron, so he ventured into Dol Guldur, barely escaping, to confirm his belief; hence the first four lines of this stanza. As for the last four, they are unclear. We know that Gollum was the long-time owner of the Ruling Ring and that when it was "stolen" from him, he emerged from his pool beneath the mountain in search of it. He was captured by Frodo along the cliffs of Emyn Muil, and led him by secret paths into Mordor. When Frodo is standing before the crack in Mount Doom preparing to throw the ring in, Gollum snatches the ring away, slips, and falls into the crack carrying the ring with him. Some believe the Ring was the "girl so fair." However, it was probably just a personal touch to the song having no relation to Tolkien. (The return of the King p. 221-225)