First Mate Owen Chase and the cabin boy Thomas Nickerson were contemporary witnesses of which maritime incident?

Chase and Nickerson were crew members of the whaling ship Essex, out of Nantucket, Massachusetts, which was rammed and sunk by a whale in the South Pacific Ocean in 1820. Twenty crew members survived the sinking but by the time they reached land twelve had perished and the remainders has resorted to cannibalism to stay alive.

Herman Melville used elements of the story in his novel "Moby Dick".

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