Book Four, The Line of Light: Nick the Convert and The Trek Summary

Gus keeps very busy with making fifteen rods and three hundred flies each month. In addition, he has a ton of wonderful gifts from bartering with his neighbors, including a small goat from Hemingway. A man named Nick is a slow but consistent worker, who asks to stay with Gus to learn how to make flies and lures like he can. The day that he leaves, Nick tells him the story of how he was injured on a submarine. When he leaves, Gus is sad.

Gus lies down after Nick leaves, thinking he will be tired with the wine. Instead, Gus's mind is filled with Nick's story. At 2 am, he makes himself a large breakfast and takes a journey to the...