How does Glendon Swarthout use imagery in Bless the Beasts and Children?

Imagery:

"Cotton's group was unique. They moved in with him because no one else would have them. They were known variously as the Weirds, the Screwups, the Locos. They were the bottom of the barrel."

"Like blind boys, they found each other, and confirmed each other and through the FM of the flesh they sent to one another impulses of courage and affection."