Darkness imagery
Darrow uses imagery to describe his imprisonment, especially the fact he was consigned to darkness: "Deep in darkness, far from warmth and suns and moons, I lie, quiet as the stone that surrounds me, imprisoning my hunched body in a dreadful womb." This use of imagery emphasizes how terrible, claustrophobic, and dark the prison is.
Withered fossil imagery
Darrow also uses imagery to describe the effect his imprisonment has on his body, saying that he could "only curl in a ball, a withered fossil of the man that was." By comparing him to a fossil, Brown suggests that Darrow has been in that position for a long time, emphasizing the length of his sentence.
Mustang imagery
When dreaming of Mustang, Darrow uses imagery to describe her: "A vision of her is spawned in the darkness like so many before it- a girl riding away from me across a field of green, twisting in her saddle and laughing for me to follow." Here, he presents Mustang as being carefree with the use of imagery.
