During one of the most devastating moments of Solomon’s time as an enslaved person—when Tibeats and Chapin leave him to hang by a noose with his feet barely touching the ground for hours—he uses pathos (a persuasive writing device) to appeal to his readers’ emotions:
Never did the sun move so slowly through the heavens—never did it shower down such fervent and fiery rays, as it did that day. […]. Suffice it to say, during the whole long day I came not to the conclusion, even once, that the southern slave, fed, clothed, whipped and protected by his master, is happier than the free colored citizen of the North […] There are many, however, even in the Northern States, benevolent and well-disposed men, who will pronounce my opinion erroneous, and gravely proceed to substantiate the assertion with an argument. Alas! they have never drunk, as I have, from the bitter cup of slavery.
In this passage, Solomon moves from the agonizing experience of being hanged by a noose (“never did the sun move so slowly through the heavens”) to persuasive analysis of this experience (“I came not to the conclusion, even once, that the southern slave, fed, clothed, whipped and protected by his master, is happier than the free colored citizen of the North”). In this way, he encourages readers to consider the horrors of his experience the next time they come across someone making an uninformed argument in favor of slavery.
Solomon also uses ethos at the end of this passage when he writes that some people may denounce his opinions on slavery but that “they have never drunk, as I have, from the bitter cup of slavery.” Ethos, as a persuasive device, is the demonstration of authority in an argument. Because Solomon has lived experience of slavery, he is arguing, readers should trust that he knows the "bitter" truth about the institution.
While this is a memoir detailing Solomon’s 12 years in slavery, it is also a piece of Abolitionist literature seeking to encourage sympathetic white readers to take action against the unjust institution and thus uses several persuasive writing techniques like pathos and ethos.