What metaphors are used in Narrative of the Life of Frederick Douglass, an American Slave, Written by Himself by Frederick Douglass?

Douglass uses animal metaphor to suggest that slave owners were not exempt from being perceived as animals by the slaves themselves. Mr. Covey, for example, is referred to by the slaves who work for him as "the snake." After Douglass' escape, he felt like "one who had escaped a den of hungry lions." The animal imagery Douglass uses is complicated by the system of slavery that produced bestial behavior regardless of race.