Born the prince of Dukandarra, Guinea, Broteer Furro was captured by slave traders at age six. As Broteer stepped off the African continent and onto a cargo ship bound for Rhode Island, the vessel's steward purchased the boy and gave him a new name: Venture. The young man crossed the Atlantic Ocean, landed in Narragansett, and worked through three decades of slavery to buy not only his own freedom but also the freedom of his wife and children. Remarkable...