For years on the morning of every April 1, I could count on my young daughters rigging the kitchen sink faucet to spritz anyone who turned it on. “You rascals!” I’d yell as they looked on, cackling. “You rapscallions! You scamps!”

The playful April Fool’s prank boasts a long history. In Geoffry Chaucer’s late 14th century “The Nun’s Priest’s Tale,” a fox outfoxes the rooster Chanticleer “syn March bigan thritty days and two.” In Scotland, merry pranksters have long observed Gowkie Day on April first— “gowk” means “fool” in the Scots tongue. The French tradition is called poisson d’Avril, when the pranked may have a paper fish impishly pinned to their backs, making them a target. (Foolish fish, you see, are easily lured, and caught.)

And these days, Google routinely hoaxes users on April 1 with reports of pigeons calculating clicks on webpages, an energy drink that could scan the drinker’s DNA, a toilet internet service provider, a rugby ball with a GPS tracker, and “Google Nose,” a feature that sniffs out information, and so on.

A Hippo’s Footprints

In Ithaca, New York, the winter of 1926, a Cornell University student, an inspired prankster named Hugh Troy, swiped from a professor’s house an umbrella stand fashioned from the foot of a rhinoceros. He used it to leave a trail that led to a hole in frozen Beebee Lake. The lake served as the campus reservoir. The vision of a drowned rhino decomposing in the water supply unnerved college officials. A twist. This story, much retold, may itself be a century-old hoax.

But it is true that Troy, who became an illustrator of children’s books (and, not incidentally, an Army intelligence officer during........

© Psychology Today