J. M. W. Turner's Slave Ship (Slavers Throwing Overboard the Dead and Dying--Typhoon Coming On) is based on an actual incident of a ship captain trying to lighten his ship in a typhoon by throwing slaves into the ocean. From the Norton Anthology of English Literature: 

The subject of Turner's painting--slaves thrown overboard, still in chains, as a storm approaches--is the occasion for apocalyptic use of light and color. For several years, John Ruskin owned this painting, a gift from his father; but he later sold it, finding the subject "too painful to live with." 

This painting probably contributed to the passing of a British law against the slave trade in 1843.