Final answer:
The narrator finds inspiration in a book that helps him argue against slavery and gain his emancipation.
Step-by-step explanation:
From this excerpt, we learn that the narrator, who is a slave, found solace and inspiration in a book called 'The Columbian Orator'. In this book, the narrator read a dialogue between a master and his slave, where the slave made smart and impressive arguments against slavery, ultimately leading to his emancipation. This information enhances our understanding of slavery in the United States by showing that even in the face of oppression, slaves could educate themselves, think critically, and challenge the institution of slavery.