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The document is the preface to the 1920 novel "Black Bartlemy's Treasure" by Jeffery Farnol. It sets the scene aboard a Spanish slave galley called the Esmeralda, where the narrator is chained to an oar as a galley slave. After his fellow slave dies, the narrator sees an opportunity to free himself from his chains and take revenge on his captors as an English ship is engaged in battle with the Esmeralda.