Twain’s “Life on the Mississipi” is a memoir of the author’s experiences when he was a steamboat pilot and traveled along the Mississipi River. This book is half a history and half a memoir of his moments. He basically tells the story of the riverand his personal story with the river and the part it had on his life growing up.
It’s a different approach than Frederick Douglas, who writes a memoir of his life as a slave. He also uses the Narrative to write a treatise on abolition when he tells the reader his fight to become a freeman. He mostly used his book as an abolitionist weapon, this is why he uses true names or places.
