Sea Monsters on Medieval and Renaissance Maps by Chet Van Duzer London: The British Library, 143 pp., $35.00 (Distributed in the US by the University of Chicago Press) Sea Monsters: A Voyage Around the World’s Most Beguiling Map by Joseph Nigg University of Chicago Press, 160 pp., $40.00 Witches and Wicked Bodies an exhibition at the Scottish National Gallery of Modern Art, Edinburgh, July 27–November 3, 2013; and the British Museum, London, September 2014–January 2015 Catalog of the exhibition by Deanna Petherbridge. National Galleries of Scotland, 128 pp., £14.95 (paper)

In “The Tale of ’Abd Allah of the Land and ’Abd Allah of the Sea” from the Arabian Nights, a poor fisherman fails day after day to catch anything but at last, in answer to his ever more desperate prayers, he feels something heavy land in his net. Joyfully, he hauls it up, only to find a merman, who begs for mercy—and for fresh fruit and vegetables, which are greatly lacking under the sea, he tells his captor. He promises that if the fisherman will bring him the produce and then release him back into the water, he’ll return with lavish recompense. ’Abd Allah of the Land doesn’t believe him, but lets him go anyway out of the goodness of his heart.

But this is a fairy tale, and so the merman will keep his word and rise again from the depths with basketfuls of fabulous gems from the sea bed—pearls and coral and chrysolites and other precious minerals—for his deliverer. Fruitful exchanges continue between them, and eventually, ’Abd Allah of the Sea invites his earthly friend down into the underwater world where, he tells him, he lives in one of many fine and diverse marine cities, each with its own society and culture. The fisherman protests that he will choke on seawater and drown. But the merman has a remedy: a powerful grease from a monstrous and terrifying fish called a dandan: “It is larger than any animal you have on land and were it to come across a camel or an elephant, it would swallow them up.”

The dandan’s liver—or in some versions of the tale its blubber—exudes a potent ointment that “looked like cow’s grease, golden yellow in colour, with a clean smell.” The substance is indispensable to mer-people for their own survival under the sea, but they cannot harvest it without human help. The monster is ferocious and deadly and voracious for flesh, mer- and other; however, it has a fatal flaw: it can’t abide the sound of a human voice. As the great fish approaches, intent on devouring him, ’Abd Allah of the Land must cry out. The mighty dandan will then keel over and die, and ’Abd Allah of the Sea will be able to harvest the precious secretion.

And so it comes about.

Now properly smeared all over in the wonder grease, ’Abd Allah of the Land is given a full tour of the extensive settlements, where different peoples and creatures dwell under the sea. He learns in amazement of the symbiosis between fish and humans, and then finds himself collected by the sultan of the sea for his cabinet of curiosities. When the merman’s…