The Four-Pools Mystery - Jean Webster

In The Four Pools Mystery the tyrannical plantation owner is deemed responsible for his own murder because of his mistreatment of the former slaves who continued in his employment after the war.
Jean Webster (pseudonym for Alice Jane Chandler Webster) was born July 24, 1876 and died June 11, 1916. She was an American writer and author of many books including Daddy-Long-Legs and Dear Enemy. (Wiki)