What are the names of the slaves in Oliver Optic's Rich and Humble, published in 1863?

There are no slaves explicitly mentioned in Rich and Humble, Or, The Mission of Bertha Grant: A Story for Young People by Oliver Optic. Considering the book was published in 1863 and is set in New York, this is not terribly surprising. Slavery was abolished in the state of New York by that time. However, the book does make mention of servants in the employment of Bertha's father, Mr. Grant. The following are those who are named:
Ben - The boatman is a former sailor and a constant presence in Bertha's life. Notably, he suspects and then discovers that Richard, Bertha's brother, stole ten dollars from her to gamble with.
Mrs. Green - Mrs. Green is the housekeeper. She taught Bertha how to make dresses and helps care for Noddy after his fall. 
John - His position is not explicitly named, but he is responsible for providing the horses used to pull a boat out of a river. Presumably, his name is the origin for a pseudonym that Richard uses earlier in the story.