Does Frederick Douglass use figurative language in Narrative of the Life of Frederick Douglass, An American Slave?

After teaching himself to write, Frederick Douglass became as master at creating a spellbinding story, full of persuasive techniques needed to spread awareness of the horrors of slavery and using writing techniques to hold readers's attention. He knew that figurative language would work. Here are some of the examples from his narrative:
When describing his own aunt's beatings, Douglass writes this:

No words, no tears, no prayers from his gory victim, seemed to move his iron heart from its bloody purpose.

Here, Douglass uses the metaphor of an "iron heart" to describe how unmoving and unfeeling his master was in these beatings. He continues this scene with startlingly vivid imagery:

The louder she screamed, the harder he whipped; and where the blood ran fastest, there he whipped longest. He would whip to make her scream, and whip to make her hush; and not until overcome by fatigue, would he cease to swing the blood-clotted cowskin.

Douglas wants the reader to wince at this imagery. He wants this to be so uncomfortable for the reader that he or she is compelled to demand a change in society. Douglas describes the first time he witnessed a beating this way:

It was a blood-stained gate, the entrance to the hell of slavery . . .

Again, Douglass uses the metaphor of a "blood-stained gate" as a comparison to describe the horrors of this experience. He goes one step further and uses the metaphor to convey that he walked through the gates of hell itself when he first witnessed a beating.
Later Douglass talks about the songs that he used to hear when he was confined in slavery, songs that "told a tale of woe beyond [his] comprehension." He uses personification in this statement:

Those songs still follow me.

Douglass says that as he still hears the echoes of these songs being sung, it forever deepens his hatred of slavery and all it represents. People long for freedom and cry out for it in their souls; the songs he can still hear tell of this desperation.
The most powerful tool that Douglass uses in his narrative is imagery, often shocking enough to make the reader cringe. Additionally, he also weaves other literary devices into his adept wording as well to craft a compelling and persuasive narrative.