In the third chapter of Herman Melville’s Moby Dick , the novel’s protagonist, Ishmael, enters the Spouter Inn in search of passage onto a whaling ship. He soon encounters an age-darkened oil painting in the entranceway and becomes perplexed. The canvas is so covered in scratches and smoky residue that it’s all but impossible to make sense of. Throwing open a window to gain more light, Ishmael attempts to describe what he sees: what most puzzled and confounded you was a long,...