Thirteenth-century professor Thaddeus of Bologna once claimed anyone who ate eggplant for nine days would go insane. A student decided to test the theory and after nine days returned to report he was not mad. Thaddeus asked him to turn around; on observing the student’s behind he announced, “All this about the eggplant has been proved.” It is said the student subsequently wrote a learned treatise on the subject.

In the Arabian Nights, Shahrazad tells of a merman who guides a fisherman around the ocean floor, where underwater societies shun clothing, commerce, and religious restrictions. “I have seen enough,” the fisherman says after eighty days, “for I am getting tired of eating fish.”

Hero of Alexandria invented the aeolipile, a primitive steam engine, in the first century. A hollow sphere with elbow-shaped tubes mounted on an axle and suspended over a cauldron of boiling water, the engine likely could not have powered anything. “It should probably be remembered,” wrote historian William Rosen, “as the first in a line of engineering dead ends.”

In the 1860s editor William Bullock invented a printing press that used continuous-roll paper; it made double-sided copies in mass quantities and transformed publishing. Two years later Bullock got his leg stuck in the press’ belt mechanism while installing one at a Philadelphia newspaper, developed gangrene, underwent an amputation, and died during the operation.