How are style and language utilized in this passage from Narrative of the Life of Frederick Douglass?

This passage, which comes from Frederick Douglass's narrative, emphasizes the cruelty of Douglass's slave master, Mr. Auld. To emphasize this cruelty, Douglass uses a number of stylistic and literary devices. 
For example, Douglass uses repetition, as he repeats the word "mean" (or "meanness") several times in the passage to drive home the point that Auld was cruel. Later, Douglass repeats the phrase "airs, words, and actions" to again make the point that Auld was trying to be the cruelest slaveholder possible by imitating people who were born slaveholders.
Douglass also uses the literary device of parallelism, which involves two phrases that are formed in the same way. An example is "at times rigid, at times lax." Repetition and parallelism are literary devices that were often found in religious sermons, and Douglass is emulating this style to make an impression on his readers. He started as an orator, and his writing has many of the features of a speech. He also uses historical allusions and compares Mr. Auld to Napoleon—a historical figure not known for his kindness. Do you note any other stylistic devices that Douglass uses to highlight Auld's cruelty?