Introduction

The first part of this story is posted under the title The Tenth Walker. That story, told from the viewpoint of Bill the Pony, follows the narrative in J.R.R. Tolkien’s The Fellowship of the Ring as closely as possible from Bree to the Doors of Moria. In contrast, this continuation of Bill’s story is highly speculative since Tolkien mentions nothing more about Bill between the attack of the Watcher in the Water and his appearance in Bree “as shaggy as an old dog and as lean as a clothes-rail but ... alive”. 

Bill’s journey back to Bree, comprising the first part of this continuation, obviously involves no familiar Hobbits, Men, Wizards, Dwarves, or Wood Elves. Of course, once he reaches Bree, some familiar two-legged characters will begin to trickle into the story again. Along those lines, Bill’s reunion with his hobbits in the stables of The Prancing Pony might be considered the high point of the story, though (if all goes well) his tale won’t be quite finished at that point. Even the original text doesn't end there, after all.

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Explanatory note

The "Voices" mentioned in various places in this story refer to Gandalf's "words of guard and guiding" which Tolkien never quite explained, as far as I know. (If you have run across any explanation or insight regarding the matter that he might have provided in a letter or interview or other work, please let me know!) After deeply pondering those words and how they might guard and guide Bill, the idea of the Voices was formulated, refined, and introduced in The Tenth Walker, Chapter 126, and is applied in Chapters 127 and 128 of that work. 

From "A Journey in the Dark" in The Fellowship of the Ring by J.R.R. Tolkien:

‘He’d follow Mr. Frodo into a dragon’s den, if I led him,’ protested Sam. ‘It’d be nothing short of murder to turn him loose with all these wolves about.’ 

‘It will be short of murder, I hope,’ said Gandalf. He laid his hand on the pony’s head, and spoke in a low voice. ‘Go with words of guard and guiding on you,’ he said. ‘You are a wise beast, and have learned much in Rivendell. Make your ways to places where you can find grass, and so come in time to Elrond’s house, or wherever you wish to go.

‘There, Sam! He will have quite as much chance of escaping wolves and getting home as we have.’

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