A Puzzle Solved Summary

The narrator briefly steps outside the events of the story and into his own time at the beginning of the chapter. He refers to several supposedly well-known books that have been written about Unk and Boaz's time in the caves of Mercury, including a popular children's book. Addressing the reader, the narrator says that of course the message on the wall of the cave was written by Rumfoord, who materializes in the caves every fourteen days.

After three years on Mercury, Unk finds the footprints of a large dog in the dust on the cave floor. Before that time, Unk and Boaz had long since gone separate ways, no longer living in the space ship, but using it to store their large supply of provisions. Boaz had set up a permanent place to live not far from the ship...