How does Robert Cormier use imagery in After the First Death?

Imagery:

"'I keep thinking I have a tunnel in my chest. The path the bullet took, burrowing through the flesh and sinew and whatever muscle the bullet encountered (I am not the macho-muscled type, not at five eleven and one hundred eighteen pounds).'"

"The spinning was building momentum now, and Kate feared Artkin would lose his hold on the child, who would go spinning off into the air, over the side of the bridge, falling to the river below."