{"contentVersion":"hunch-v1","subjects":[{"id":"octopus","answer":"Octopus","display":"an octopus","aliases":["octopuses","octopi","the octopus","common octopus"],"category":"animal","clues":["Its three hearts pump blue, copper-based blood, and the main one stops beating whenever it swims.","Two-thirds of its neurons live in its arms, so each limb can taste and explore on its own.","It can squeeze its boneless body through any gap wider than its beak.","A famous one named Paul correctly predicted eight match results at the 2010 World Cup.","This eight-armed sea creature squirts ink and changes colour in a blink."],"fact":"In 2016 an octopus named Inky escaped New Zealand’s National Aquarium by slipping through a drainpipe back to the sea."},{"id":"giraffe","answer":"Giraffe","display":"a giraffe","aliases":["giraffes","the giraffe"],"category":"animal","clues":["Its 45-centimetre tongue is a dark bluish-purple, which may act as sunscreen during all-day browsing.","For all that reach, its neck holds just seven vertebrae, exactly as many as yours.","It gets by on under five hours of sleep a day, often dozing upright in short bursts.","Its newborns drop nearly two metres to the ground at birth, then wobble upright within hours.","It’s the tallest living land animal, browsing African treetops on a spectacularly long neck."],"fact":"No two giraffes share the same coat: each one’s patch pattern is unique, like a fingerprint."},{"id":"honeybee","answer":"Honeybee","display":"a honeybee","aliases":["honey bee","honeybees","bee","bees"],"category":"animal","clues":["Making half a kilo of its signature product takes visits to about two million flowers.","Males of its kind perish immediately after mating, and every single worker is female.","A queen can lay around 2,000 eggs in a day at her summer peak.","It reports the direction and distance of food with a figure-of-eight waggle dance.","This striped, buzzing pollinator makes honey and can sting you only once."],"fact":"Karl von Frisch decoded the waggle dance and shared the 1973 Nobel Prize for it."},{"id":"penguin","answer":"Penguin","display":"a penguin","aliases":["penguins","the penguin","emperor penguin"],"category":"animal","clues":["Scientists count one species’ colonies from space by the brown stains its droppings leave on ice.","It happily drinks seawater, sneezing out the excess salt through a gland above its eyes.","The largest kind incubates a single egg on its feet through polar winter, the male fasting for about two months.","The tuxedo look is camouflage: dark back against the deep for predators above, pale belly for those below.","This flightless black-and-white bird waddles across Antarctic ice and flies only underwater."],"fact":"Gentoos are the fastest penguins, swimming at up to about 36 km/h."},{"id":"kangaroo","answer":"Kangaroo","display":"a kangaroo","aliases":["kangaroos","the kangaroo","red kangaroo"],"category":"animal","clues":["A female can put a pregnancy on pause, keeping an embryo on standby until her pouch is free.","It cools off by licking its forearms, where a dense web of blood vessels sheds heat.","It can’t easily move backwards, one reason it shares Australia’s coat of arms with the emu.","Its newborn is the size of a jellybean and crawls unaided up into its mother’s pouch.","This bounding marsupial carries a joey in its pouch and boxes with powerful hind legs."],"fact":"A group of kangaroos is called a mob, and big males are nicknamed boomers."},{"id":"chameleon","answer":"Chameleon","display":"a chameleon","aliases":["chameleons","the chameleon"],"category":"animal","clues":["Some small species fire their tongues from 0 to nearly 100 km/h in a hundredth of a second.","Its colour changes come from tuning nanocrystals in its skin, not just from pigments.","It shifts colour less for hiding and more for mood, temperature, and showing off.","It grips branches with fused, mitten-like toes and a curling, grasping tail.","This colour-shifting lizard swivels each eye independently and snags insects with a sticky tongue."],"fact":"The smallest chameleon, Brookesia nana, perches comfortably on a fingertip and may be the tiniest reptile on Earth."},{"id":"hummingbird","answer":"Hummingbird","display":"a hummingbird","aliases":["hummingbirds","humming bird"],"category":"animal","clues":["Its heart can race past 1,200 beats a minute, yet on cold nights it slips into a mini-hibernation called torpor.","Its tongue works like a tiny pump, trapping nectar as it darts in and out many times a second.","It’s the only bird that can truly fly backwards.","Some weigh less than a coin yet cross the Gulf of Mexico nonstop on migration.","This tiny hovering bird beats its wings dozens of times a second, making the sound it’s named for."],"fact":"Cuba’s bee hummingbird is the world’s smallest bird, lighter than a US penny."},{"id":"blue-whale","answer":"Blue Whale","display":"a blue whale","aliases":["the blue whale","blue whales"],"category":"animal","clues":["Its heart weighs around 180 kilograms and can slow to two beats a minute on deep dives.","Its deep moans rank among the loudest animal sounds and can carry across hundreds of kilometres of ocean.","It grows to about 30 metres long on a diet of finger-sized krill, millions of them a day.","Its tongue alone can weigh as much as an elephant.","It’s the largest animal ever known to have lived, a baleen giant named for its slate-blue colour."],"fact":"A blue whale calf gains roughly 90 kilograms a day on its mother’s milk."},{"id":"sloth","answer":"Sloth","display":"a sloth","aliases":["sloths","the sloth","three-toed sloth"],"category":"animal","clues":["Algae grows in its fur, tinting it green and feeding moths that live nowhere else.","It climbs down from its tree about once a week to poo, the most dangerous errand of its life.","Extra neck vertebrae let some kinds turn their heads through nearly 270 degrees.","It’s a surprisingly strong swimmer, moving faster in water than it ever does on land.","This slow, upside-down tree-dweller naps away much of the day in Central and South America."],"fact":"Its extinct cousins included ground-dwelling giants the size of elephants that roamed the Americas until about 10,000 years ago."},{"id":"owl","answer":"Owl","display":"an owl","aliases":["owls","the owl","barn owl"],"category":"animal","clues":["Its eyes are fixed tubes, so it swivels its head as much as 270 degrees instead of glancing sideways.","Asymmetrical ears, one set higher than the other, let some kinds strike prey by sound alone in total darkness.","Comb-like fringes on its flight feathers make its swoop almost perfectly silent.","It gulps prey whole, then coughs up tidy pellets of fur and bone.","This night-hunting bird of hoots, with a heart-shaped or horned face, is the storybook symbol of wisdom."],"fact":"A group of owls is called a parliament."},{"id":"elephant","answer":"Elephant","display":"an elephant","aliases":["elephants","the elephant","african elephant"],"category":"animal","clues":["Its closest living relatives include the small, furry hyrax and the sea-going manatee.","It chats over kilometres in infrasonic rumbles pitched too low for human ears.","It can’t jump, and it walks almost on tiptoe atop a fatty cushion inside each foot.","Its trunk holds tens of thousands of muscle units and can lift a log or pluck a single peanut.","It’s the largest living land animal, with great flapping ears and ivory tusks."],"fact":"Elephants can recognize themselves in a mirror, a rare sign of self-awareness shared with apes and dolphins."},{"id":"honey","answer":"Honey","display":"honey","aliases":["raw honey"],"category":"food","clues":["Low moisture, natural acidity, and a trace of hydrogen peroxide make it nearly impossible for microbes to spoil.","A single worker produces only about one-twelfth of a teaspoon of it in her whole lifetime.","A rock painting in a Spanish cave shows humans raiding a wild hive for it at least 8,000 years ago.","Its colour and flavour depend on which flowers were visited, from pale clover to dark buckwheat.","This golden, sticky sweetener is made by bees from nectar and stored in hexagonal wax cells."],"fact":"To make one pound of honey, a hive’s bees fly a combined distance of roughly 55,000 miles."},{"id":"chocolate","answer":"Chocolate","display":"chocolate","aliases":["dark chocolate","milk chocolate"],"category":"food","clues":["The Aztecs valued its key ingredient so highly that the beans doubled as currency.","Its key molecule, theobromine, takes its name from the Greek for ‘food of the gods’. It is also toxic to dogs.","Its cocoa butter melts just below body temperature, which is why it dissolves so readily on your tongue.","The Swiss eat more of it per person than almost anyone else on Earth.","This sweet brown treat comes in bars and in dark, milk, and white varieties."],"fact":"White chocolate contains no cocoa solids at all: just cocoa butter, milk, and sugar."},{"id":"banana","answer":"Banana","display":"a banana","aliases":["bananas"],"category":"food","clues":["It’s mildly radioactive thanks to potassium-40; physicists even use it as an informal radiation unit.","Botanically it’s a berry, and the ‘tree’ it grows on is really a giant herb.","Nearly every exported one is a clone of a single variety, the Cavendish, leaving the crop exposed to one fungus.","It grows in hanging bunches called hands, each fruit a ‘finger’ curving up toward the light.","This yellow, peelable fruit is a lunchbox classic and slapstick’s favourite slipping hazard."],"fact":"The Cavendish took over after Panama disease commercially wiped out its tastier predecessor, the Gros Michel, in the 1950s."},{"id":"cheese","answer":"Cheese","display":"cheese","aliases":["cheeses"],"category":"food","clues":["A 3,600-year-old sample of it was found on mummies buried in China’s Taklamakan Desert.","It’s traditionally set with rennet, an enzyme originally scraped from calves’ stomachs.","The holes in the Swiss kind are bubbles of carbon dioxide blown by bacteria.","France alone boasts hundreds of named varieties, from soft Brie to blue Roquefort.","This dairy product tops pizzas, fills sandwiches, and is what photographers ask you to say."],"fact":"Cheddar, Brie, Gouda, and Parmesan are all named after places."},{"id":"pizza","answer":"Pizza","display":"pizza","aliases":["pizzas","pizza pie"],"category":"food","clues":["In 2001 a fast-food chain paid the Russian space agency to deliver one to the International Space Station.","The true Neapolitan version is protected by the EU as a ‘traditional speciality guaranteed’.","Legend credits its best-known topping combo to an 1889 tribute to Queen Margherita in red, white, and green.","Americans put away roughly 350 slices of it every second.","This round, cheesy Italian flatbread arrives hot in a flat cardboard box."],"fact":"UNESCO added the art of the Neapolitan pizzaiuolo to its intangible cultural heritage list in 2017."},{"id":"coffee","answer":"Coffee","display":"coffee","aliases":["a cup of coffee"],"category":"food","clues":["Beethoven reportedly brewed his with a count of exactly 60 beans per cup.","It grows in a belt hugging the equator and ranks among the world’s most traded farm commodities.","Legend says an Ethiopian goatherd named Kaldi discovered it after his goats started dancing.","One luxury version, kopi luwak, is made from beans that have passed through a civet.","This dark, caffeinated morning brew comes as espresso, latte, and cappuccino."],"fact":"Finland drinks more coffee per person than any other country."},{"id":"popcorn","answer":"Popcorn","display":"popcorn","aliases":["pop corn"],"category":"food","clues":["Kernels of it found in New Mexico’s Bat Cave are several thousand years old.","Each kernel is a tiny pressure cooker, reaching roughly nine atmospheres at about 180 °C before bursting.","High-speed cameras show it somersaulting like a tiny gymnast at the moment it bursts.","American movie theatres embraced it during the Great Depression as an affordable luxury.","This fluffy white cinema snack explodes from heated kernels and comes salted or buttered."],"fact":"Kernels that fail to pop are known in the trade as old maids."},{"id":"avocado","answer":"Avocado","display":"an avocado","aliases":["avocados","avocado pear"],"category":"food","clues":["Its oversized seed likely evolved for giant Ice Age beasts that swallowed the fruit whole, all of them long extinct.","It refuses to ripen on the tree, so growers can leave it hanging for months like living storage.","It’s an outlier among fruit: most of its calories come from fat, not sugar.","Mexico grows by far the most, and demand spikes every year around the Super Bowl.","This green-fleshed, single-stoned fruit gets mashed into guacamole and smeared on brunch toast."],"fact":"Nearly every Hass avocado descends from a single tree planted by California postman Rudolph Hass in the 1920s."},{"id":"ketchup","answer":"Ketchup","display":"ketchup","aliases":["catsup","tomato ketchup","tomato sauce"],"category":"food","clues":["It began as a fermented fish sauce in Asia, and early Western versions used mushrooms or walnuts.","In the 1830s an American doctor declared the tomato medicinal, and ‘tomato pills’ were soon sold in pharmacies.","It’s a classic shear-thinning fluid, which is why a confident smack suddenly gets it flowing.","Heinz reportedly rejects any batch that pours from the glass bottle faster than 0.028 miles per hour.","This sweet-tangy red condiment gets squeezed onto fries, burgers, and hot dogs."],"fact":"The word likely comes from Hokkien Chinese ‘kê-tsiap’, the name of a fermented fish brine."},{"id":"ice-cream","answer":"Ice Cream","display":"ice cream","aliases":["icecream","ice-cream"],"category":"food","clues":["Victorian cook Agnes Marshall proposed freezing it with liquefied gas back in 1901.","The soft-serve kind is simply churned with extra air, which also makes it cheaper to sell.","As the story goes, its cone was popularized at the 1904 St. Louis World’s Fair when a vendor ran out of dishes.","Vanilla, not chocolate, is reliably its best-selling flavour.","This frozen dairy dessert arrives in scoops, cones, and tubs, or from a jingling truck."],"fact":"Häagen-Dazs isn’t Danish: the name was invented in New York to sound appealingly Scandinavian."},{"id":"watermelon","answer":"Watermelon","display":"a watermelon","aliases":["watermelons","water melon"],"category":"food","clues":["Botanically its giant fruit is a kind of berry called a pepo, cousin to cucumbers and pumpkins.","Seeds of it were laid in ancient Egyptian tombs, including Tutankhamun’s.","The heaviest one on record, grown in Tennessee in 2013, weighed 159 kilograms.","Japanese farmers grow cube-shaped ones inside boxes and sell them as luxury gifts.","This huge green-striped picnic fruit hides pink flesh, black seeds, and about 91 per cent water."],"fact":"In 2007 Oklahoma declared it the official state vegetable, not fruit."},{"id":"eiffel-tower","answer":"Eiffel Tower","display":"the Eiffel Tower","aliases":["the eiffel tower","eiffel","tour eiffel","la tour eiffel"],"category":"place","clues":["Its 18,000-odd iron pieces are held together by 2.5 million rivets and repainted roughly every seven years.","Summer heat makes it grow up to 15 centimetres taller through thermal expansion.","Built to stand for just 20 years, it was saved from demolition by the radio antenna on top.","Con artist Victor Lustig ‘sold’ it for scrap. Twice.","This wrought-iron Paris landmark from the 1889 World’s Fair sparkles with lights every night."],"fact":"Gustave Eiffel kept a private apartment near the top, where he entertained Thomas Edison."},{"id":"great-wall-of-china","answer":"Great Wall of China","display":"the Great Wall of China","aliases":["the great wall of china","great wall","the great wall"],"category":"place","clues":["Sticky rice was mixed into the mortar of its Ming-era sections, making them remarkably durable.","Folk tales say some of the workers who died building it were buried within it.","Built and rebuilt over two millennia, its oldest stretches predate the Roman Colosseum by centuries.","Despite the legend, astronauts say it’s barely visible from low orbit, and not at all from the Moon.","This serpentine stone fortification with watchtowers snakes along the ridges of northern China."],"fact":"A 2012 official survey measured all its branches at 21,196 kilometres, more than half Earth’s circumference."},{"id":"sahara-desert","answer":"Sahara Desert","display":"the Sahara Desert","aliases":["the sahara","sahara","the sahara desert"],"category":"place","clues":["Its wind-borne dust crosses the Atlantic and fertilizes the Amazon rainforest with phosphorus.","Around 6,000 years ago it was green savanna with lakes, hippos, and human herders.","Snow has dusted its dunes several times in living memory, around the Algerian town of Aïn Séfra.","It’s nearly as large as the whole United States, spanning about a dozen countries.","This vast North African expanse of dunes, camels, and oases is the world’s largest hot desert."],"fact":"Only about a quarter of it is sand dunes; most is gravel plain and bare rock."},{"id":"mount-everest","answer":"Mount Everest","display":"Mount Everest","aliases":["everest","mt everest","mt. everest","sagarmatha","chomolungma"],"category":"place","clues":["Its summit rock is marine limestone, laid down on an ancient ocean floor.","It gains roughly four millimetres of height a year as India keeps shoving into Asia.","Story goes its 1850s surveyors computed exactly 29,000 feet but published 29,002, so it wouldn’t look like a rounded guess.","Climbers queue in its ‘death zone’, where the air holds a third of sea-level oxygen.","This Himalayan giant on the Nepal-China border is Earth’s highest peak, at 8,849 metres."],"fact":"Its Tibetan name, Chomolungma, is often translated as ‘Goddess Mother of the World’."},{"id":"venice","answer":"Venice","display":"Venice","aliases":["venezia"],"category":"place","clues":["It stands on millions of timber piles driven into mud, hardened over centuries in oxygen-poor water.","Its long-lived republic was led by an elected duke with a distinctive title: the Doge.","Its 118 islands are laced by canals and stitched together by more than 400 bridges.","It throws a masked Carnival every year, and its singing boatmen must pass a licensing exam.","This sinking Italian lagoon city has canals for streets and gondolas for taxis."],"fact":"The word ‘quarantine’ traces to the Venetian ‘quarantena’, the 40-day isolation imposed on plague-era ships."},{"id":"grand-canyon","answer":"Grand Canyon","display":"the Grand Canyon","aliases":["the grand canyon"],"category":"place","clues":["Rocks at its bottom are nearly two billion years old, almost half the age of Earth.","A billion years of rock layers are simply missing from its walls, a puzzle called the Great Unconformity.","One river spent five to six million years carving it up to a mile deep.","Mule trains still carry visitors down its Arizona trails, and the Colorado River glints at the bottom.","This immense red-rock gorge in the American Southwest is 446 kilometres long and a wonder of the world."],"fact":"Spanish explorers reached it in 1540, and then no European is recorded visiting for over 200 years."},{"id":"antarctica","answer":"Antarctica","display":"Antarctica","aliases":["the antarctic","antarctic"],"category":"place","clues":["Parts of its Dry Valleys may have gone without rain for nearly two million years.","It locks up around 70 per cent of Earth’s fresh water as ice sheets up to 4.8 kilometres thick.","No country owns it: a 1959 treaty reserves the whole place for peace and science.","It has no permanent residents, only rotating scientists and a tourist post office run beside a penguin colony.","This frozen southern continent surrounds the South Pole."],"fact":"The coldest temperature ever recorded on Earth, −89.2 °C, was measured at its Vostok Station in 1983."},{"id":"amazon-river","answer":"Amazon River","display":"the Amazon River","aliases":["the amazon","amazon","the amazon river","rio amazonas"],"category":"place","clues":["It pours out more water than the next several biggest rivers combined: about a fifth of all river flow to the sea.","Once a year a tidal bore called the pororoca sends surfable waves far upstream.","Pink dolphins and even bull sharks swim in it, thousands of kilometres from the ocean.","For all its 6,400-kilometre length, not a single bridge crosses its main stem.","This South American giant drains the world’s largest rainforest and lends its name to an online superstore."],"fact":"It once flowed the other way: before the Andes rose, its ancestral waters drained toward the Pacific."},{"id":"great-barrier-reef","answer":"Great Barrier Reef","display":"the Great Barrier Reef","aliases":["the great barrier reef","barrier reef"],"category":"place","clues":["It’s bigger than Italy, yet its billions of tiny builders are each only millimetres across.","It’s the largest structure on Earth made by living creatures, visible even from orbit.","On a few nights after a full moon, its corals spawn all at once in a synchronized underwater blizzard.","Its 2,300-kilometre sweep takes in about 900 islands and hundreds of coral species.","This vast living wonder off Queensland, Australia is the snorkelling trip of a lifetime."],"fact":"It shelters about 1,500 fish species and six of the world’s seven sea-turtle species."},{"id":"statue-of-liberty","answer":"Statue of Liberty","display":"the Statue of Liberty","aliases":["the statue of liberty","lady liberty","liberty enlightening the world"],"category":"place","clues":["Her copper skin is only 2.4 millimetres thick, hung on an iron skeleton engineered by Gustave Eiffel.","She moonlighted as a working lighthouse for her first 16 years.","She crossed the Atlantic in 350 pieces, a gift from one republic to another.","She started out shiny reddish-brown; a few decades of weather turned her green.","This torch-bearing colossus welcomes ships into New York Harbor."],"fact":"Her sandals work out to roughly a US shoe size 879."},{"id":"dead-sea","answer":"Dead Sea","display":"the Dead Sea","aliases":["the dead sea"],"category":"place","clues":["It was one of the world’s first health resorts, and its mineral-rich black mud still gets slathered on spa-goers.","It’s shrinking by about a metre a year, leaving treacherous sinkholes along its retreating shore.","Its shore, about 430 metres below sea level, is the lowest dry land on Earth.","Nearly ten times saltier than the ocean, it floats swimmers so well they can read a newspaper.","This hypersaline lake between Israel and Jordan is so lifeless that its name says so."],"fact":"The Dead Sea Scrolls were found in caves above its northwestern shore in the 1940s."},{"id":"umbrella","answer":"Umbrella","display":"an umbrella","aliases":["umbrellas","parasol","brolly"],"category":"object","clues":["Egyptian and Assyrian art shows royalty shaded by early versions; for centuries it was strictly a sunshade.","Jonas Hanway was mocked for decades in 1750s London for carrying one; gentlemen were expected to just get wet.","Its name comes from the Latin for shade, though the British mostly deploy it against something else.","A 2007 Rihanna chart-topper about sharing one repeats ‘ella, ella, eh’.","This collapsible canopy on a stick keeps the rain off your head."],"fact":"The telescoping pocket version was patented by Hans Haupt in 1928 and sold under the name Knirps."},{"id":"mirror","answer":"Mirror","display":"a mirror","aliases":["mirrors","looking glass"],"category":"object","clues":["The earliest known ones, from Anatolia around 6000 BC, were discs of polished obsidian.","Renaissance Venice held a jealous monopoly on the finest ones until industrial espionage smuggled the secret to France.","The modern silvered-glass version was invented by chemist Justus von Liebig in 1835.","Superstition prices breaking one at seven years of bad luck.","This reflective glass shows you your own face, flipped left to right."],"fact":"The mirror self-recognition test has been passed by great apes, dolphins, elephants, and magpies."},{"id":"candle","answer":"Candle","display":"a candle","aliases":["candles"],"category":"object","clues":["In zero gravity its flame burns as a small blue sphere instead of a teardrop.","Clock versions once told time by burning down past painted hour marks.","Cheap ones were long made of tallow, rendered animal fat, and smelled like it; beeswax was for the rich.","Michael Faraday built a whole Royal Institution lecture series around the chemistry of its flame.","This wax stick with a wick tops birthday cakes, one small flame per year."],"fact":"One theory traces birthday-cake flames to ancient Greek moon-shaped offerings to Artemis."},{"id":"piano","answer":"Piano","display":"a piano","aliases":["pianos","pianoforte","grand piano","upright piano"],"category":"object","clues":["Bartolomeo Cristofori built the first one in Florence around 1700 for the Medici court.","Inside, every pressed key flings a felt hammer at steel strings under roughly 20 tonnes of combined tension.","Its full Italian name means ‘soft-loud’: the breakthrough was letting players control volume with touch.","It has 88 keys: 52 white and 36 black.","Beethoven sonatas, jazz bars, and first lessons all depend on this big keyboard instrument."],"fact":"‘Chopsticks’ was published in 1877 by 16-year-old Euphemia Allen under the pen name Arthur de Lulli."},{"id":"dice","answer":"Dice","display":"dice","aliases":["die","a pair of dice","six-sided dice"],"category":"object","clues":["Ancient players carved them from the ankle bones of sheep, called astragali.","Crossing the Rubicon in 49 BC, Caesar quoted a gaming proverb about one being ‘cast’.","Opposite faces of the standard cube always add up to seven.","Casino versions are transparent, with razor-sharp edges, to guarantee honest rolls.","You roll these spotted cubes in craps, Yahtzee, and Monopoly."],"fact":"Twenty-sided dice existed in Ptolemaic Egypt, two millennia before Dungeons & Dragons."},{"id":"teddy-bear","answer":"Teddy Bear","display":"a teddy bear","aliases":["teddy","teddybear","teddy bears","stuffed bear"],"category":"object","clues":["Morris Michtom in Brooklyn and Richard Steiff in Germany created it almost simultaneously around 1902.","A Washington Post cartoon by Clifford Berryman sparked the craze for it.","It exists because a US president on a 1902 Mississippi hunt refused to shoot a captive animal.","It takes its name from that president’s nickname, one he reportedly disliked.","This soft, huggable stuffed toy, a plush version of a big furry forest animal, shares beds with children everywhere."],"fact":"Steiff’s early bears wore a small metal button in the ear, still the company’s trademark today."},{"id":"boomerang","answer":"Boomerang","display":"a boomerang","aliases":["boomerangs"],"category":"object","clues":["A 20,000-year-old one carved from mammoth tusk was found in a cave in Poland.","Its curved flight comes from spinning wings generating uneven lift, like a lopsided helicopter rotor.","Most traditional Aboriginal throwing sticks were actually the non-returning kind, built for hunting.","Instagram named a looping back-and-forth video feature after it.","Throw this bent Australian wooden blade properly and it swoops right back to you."],"fact":"The word entered English from Dharug, an Aboriginal language of the Sydney region."},{"id":"compass","answer":"Compass","display":"a compass","aliases":["compasses","magnetic compass"],"category":"object","clues":["The first Chinese versions were lodestone spoons spun on bronze boards for fortune-telling, not travel.","Early navigators made one by floating a magnetized sliver of iron on water in a bowl.","It ignores the geographic pole; the spot it actually seeks has lately been dashing toward Siberia.","Reciting all 32 points of its rose in order was a sailor’s exercise called ‘boxing’ it.","This pocket instrument’s quivering needle always swings around to find north."],"fact":"Standing at the north magnetic pole, a compass needle would try to point straight down at your feet."},{"id":"kite","answer":"Kite","display":"a kite","aliases":["kites"],"category":"object","clues":["Around 200 BC a Chinese general reportedly flew one over enemy walls to measure a tunnel’s distance.","Fighting versions with glass-coated lines duel each other in South Asian festival skies.","In 1752 Benjamin Franklin risked one in a thunderstorm to probe electricity.","In English it shares its name with a graceful hovering bird of prey.","This paper-and-string flyer dances on the wind at the end of your line, tail streaming."],"fact":"Before building gliders, the Wright brothers tested their wing-warping idea on a kite in 1899."},{"id":"hourglass","answer":"Hourglass","display":"an hourglass","aliases":["hourglasses","sand timer","sandglass","sand clock"],"category":"object","clues":["Magellan’s round-the-world fleet sailed with 18 of them from Barcelona, turned by ship’s boys to mark the hours.","Unlike dripping water clocks, it kept honest time on a rolling ship.","Early Windows software made a tiny animated one the universal symbol for ‘please wait’.","Its pinched-waist silhouette lends its name to a body shape.","Flip this two-bulbed glass timer and its grains trickle down for a set spell: three minutes for an egg."],"fact":"Pirate flags sometimes featured an hourglass, telling victims their time was running out."},{"id":"balloon","answer":"Balloon","display":"a balloon","aliases":["balloons","rubber balloon","party balloon"],"category":"object","clues":["Michael Faraday made the first rubber ones in 1824, to hold hydrogen for his experiments.","Before rubber, its festive job fell to inflated animal bladders, pig bladders especially.","Rub an inflated one on your hair and it will cling to a wall by static electricity.","Filled with helium it strains skyward on its string; filled with breath it just squeaks and drifts.","Clowns twist these stretchy inflatables into dogs, and no birthday party pops without them."],"fact":"In 1982, Larry Walters strapped 42 weather balloons to a lawn chair and floated to about 4,900 metres over Los Angeles."},{"id":"zipper","answer":"Zipper","display":"the zipper","aliases":["zippers","zip","zip fastener"],"category":"invention","clues":["The mysterious letters YKK stamped on billions of them stand for a Japanese company founded in 1934.","Whitcomb Judson patented its clunky ancestor in 1893 to save people from endlessly buttoning boots.","Its everyday name imitates its sound and was coined by the B.F. Goodrich company for rubber boots in 1923.","Gideon Sundback perfected its interlocking metal teeth in 1913.","This toothed fastener slides up and down your jacket front and jeans fly."],"fact":"Early makers called it the ‘hookless fastener’; the snappy name originally belonged to the Goodrich boots it closed."},{"id":"microwave-oven","answer":"Microwave Oven","display":"the microwave oven","aliases":["microwave","microwaves","the microwave","microwave ovens"],"category":"invention","clues":["The first commercial model, 1947’s Radarange, stood nearly 1.8 metres tall, weighed 340 kilos, and was water-cooled.","It cooks by rattling water molecules billions of times a second, which is why the plate stays cooler than the food.","It was inspired when a radar magnetron melted the chocolate bar in engineer Percy Spencer’s pocket.","Forget a fork inside it and you get a light show; the mesh in its door keeps the cooking waves in.","This beeping kitchen box reheats leftovers in minutes on a rotating glass plate."],"fact":"As the story goes, popcorn was the first food deliberately cooked with it, and an egg the second, which exploded."},{"id":"velcro","answer":"Velcro","display":"Velcro","aliases":["hook and loop","hook-and-loop fastener","velcro strap"],"category":"invention","clues":["Swiss engineer George de Mestral dreamed it up in 1941 after picking burrs off his dog.","Under a microscope he saw how burrs’ tiny barbs snagged fur’s tiny loops, then copied the trick in nylon.","Its brand name fuses the French words for velvet and little hook: velours and crochet.","Apollo astronauts used it to pin down floating gear, and David Letterman once wore a suit of it to leap at a wall.","Rip this scratchy two-sided fastener open on a kid’s shoe and everyone hears it."],"fact":"NASA didn’t invent it, but the space program made it famous enough that people assume so."},{"id":"telephone","answer":"Telephone","display":"the telephone","aliases":["telephones","phone","phones","the telephone"],"category":"invention","clues":["Its inventor championed ‘ahoy’ as the proper greeting; Edison’s ‘hello’ won out.","Its 1876 patent beat a rival inventor’s similar filing lodged the very same day.","Bell reportedly refused to keep one in his study, considering it an intrusion on real work.","The first words it ever carried were ‘Mr. Watson, come here, I want to see you’.","Before going mobile and smart, it hung on kitchen walls with a rotary dial and a curly cord."],"fact":"Early exchanges employed teenage boys as operators, then switched to women; the boys were too rude on the lines."},{"id":"light-bulb","answer":"Light Bulb","display":"the light bulb","aliases":["lightbulb","light bulbs","lightbulbs","the light bulb","incandescent bulb","bulb"],"category":"invention","clues":["One of them has burned almost continuously in a Livermore, California fire station since 1901.","Edison didn’t invent it so much as perfect it, testing thousands of filaments including carbonized bamboo.","The incandescent kind squanders roughly 95 per cent of its energy as heat, so many countries phased it out.","One switching on above a cartoon character’s head is universal shorthand for a bright idea.","Screw this glowing glass globe into a lamp socket and flick the switch."],"fact":"Livermore’s ‘Centennial Light’ has its own webcam, and has outlived several of the cameras pointed at it."},{"id":"printing-press","answer":"Printing Press","display":"the printing press","aliases":["the printing press","gutenberg press","movable type"],"category":"invention","clues":["Its inventor borrowed the screw mechanism that Rhineland farmers used to crush grapes for wine.","It demanded a new oil-based ink, because water-based inks simply beaded off metal.","Within about 50 years of its debut, European workshops had turned out some 20 million volumes.","A goldsmith from Mainz introduced it to Europe around 1440, and a famous Bible followed.","This machine stamped inked metal letters onto paper, mass-produced books, and put scribes out of work."],"fact":"Only about 49 Gutenberg Bibles survive, and no complete copy has been sold since 1978."},{"id":"bicycle","answer":"Bicycle","display":"the bicycle","aliases":["bicycles","bike","bikes","pushbike"],"category":"invention","clues":["Its 1817 ancestor, Karl von Drais’s ‘running machine’, had no pedals; riders shoved along with their feet.","Exactly why it balances so well still keeps physicists busy; gyroscopes alone don’t explain it.","Susan B. Anthony said it had done ‘more to emancipate women than anything else in the world’.","Its comical penny-farthing phase perched riders over a giant front wheel, primed for headfirst dismounts.","Pedal this two-wheeler and ring the bell; once learned, you never forget how to ride it."],"fact":"The Wright brothers funded their first aeroplane with profits from their bicycle shop."},{"id":"camera","answer":"Camera","display":"the camera","aliases":["cameras","the camera"],"category":"invention","clues":["Its name is Latin for ‘chamber’, because the original was an entire darkened room with a pinhole.","The oldest surviving photograph it produced, an 1820s French window view, needed an exposure of hours if not days.","Early sitters had to hold a pose for minutes, one reason nobody in old portraits is smiling.","George Eastman’s 1888 Kodak sold it to the masses with the slogan ‘You press the button, we do the rest’.","Point this lens-and-shutter device, say cheese, and click. Nowadays it lives inside every phone."],"fact":"The first digital camera, built at Kodak in 1975, weighed 3.6 kilograms and saved 0.01-megapixel images to cassette tape."},{"id":"escalator","answer":"Escalator","display":"the escalator","aliases":["escalators","moving staircase","moving stairs"],"category":"invention","clues":["The first working one thrilled riders as a Coney Island amusement in 1896.","Its name began as a trademark; courts declared it generic in 1950, to its owner Otis’s dismay.","As the story goes, London’s first, in 1911, hired a man with a wooden leg named Bumper Harris to ride it reassuringly.","Unofficial global etiquette: stand on one side, walk on the other.","It glides commuters between floors on steps that flatten into a comb at each end."],"fact":"The verb ‘escalate’ is a back-formation: the machine and its name came first."},{"id":"sticky-note","answer":"Sticky Note","display":"the sticky note","aliases":["post-it","post it","post-it note","sticky notes","post it note"],"category":"invention","clues":["It exists because 3M chemist Spencer Silver invented a glue that was spectacularly, uselessly weak.","Colleague Art Fry adopted that failure for bookmarks that kept falling out of his church hymnal.","Its classic canary yellow was reportedly an accident: the lab next door only had yellow scrap paper.","Launched as ‘Press ’n Peel’ in 1977, it flopped until free samples blanketed Boise, Idaho.","Scribble a reminder on this small adhesive paper square and slap it on your monitor."],"fact":"The weak glue works because its adhesive sits in tiny spheres that only partly touch the surface, so it peels off clean."},{"id":"aurora-borealis","answer":"Aurora Borealis","display":"the aurora borealis","aliases":["the northern lights","northern lights","aurora","the aurora","auroras","polar lights"],"category":"phenomenon","clues":["Galileo coined its Latin name in 1619 from the goddess of dawn and the Greek north wind.","It sparks when solar-wind particles, funnelled by Earth’s magnetic field, slam into gases about 100 kilometres up.","Oxygen paints it green and red; nitrogen adds blues and purples.","Its southern twin shimmers around the opposite pole at the very same time.","These green curtains of light dance across Arctic night skies, drawing crowds to Iceland and Norway each winter."],"fact":"Some observers swear the aurora crackles, and Finnish researchers have actually recorded the faint sounds."},{"id":"rainbow","answer":"Rainbow","display":"a rainbow","aliases":["rainbows","the rainbow"],"category":"phenomenon","clues":["Descartes worked out its geometry: sunlight bending and bouncing inside raindrops at about 42 degrees.","No two people ever see exactly the same one; yours is built by light reaching your eyes alone.","It’s secretly a full circle; the ground usually hides the bottom half.","A fainter twin sometimes appears above it with its colours reversed.","Legend parks a leprechaun’s pot of gold at the end of this seven-colour arc."],"fact":"Newton originally named five colours, then squeezed in orange and indigo to reach a musical seven."},{"id":"lightning","answer":"Lightning","display":"lightning","aliases":["lightning bolt","a lightning bolt","thunderbolt"],"category":"phenomenon","clues":["Each flash briefly heats the air to about 30,000 °C, several times hotter than the Sun’s surface.","It hits Earth dozens of times every second, and Venezuela’s Lake Maracaibo catches more than anywhere.","US park ranger Roy Sullivan survived seven separate encounters with it.","Counting the seconds before the rumble tells you its distance: about three seconds per kilometre.","This jagged electric bolt splits the sky in a storm, just ahead of the thunder."],"fact":"Where lightning strikes sand, it can fuse glassy branching tubes called fulgurites."},{"id":"tornado","answer":"Tornado","display":"a tornado","aliases":["tornadoes","tornados","twister"],"category":"phenomenon","clues":["The fastest winds ever measured on Earth, about 486 km/h, were clocked inside one near Oklahoma City in 1999.","The United States records about 1,200 of them a year, far more than any other country.","The Fujita scale grades its damage from 0 to 5.","Storm chasers pursue its rotating funnel across the Great Plains every spring.","This violent spinning column drops from a thundercloud; one carried Dorothy out of Kansas."],"fact":"Over water it goes by a gentler name: a waterspout."},{"id":"tides","answer":"Tides","display":"the tides","aliases":["the tides","tide","the tide","ocean tides"],"category":"phenomenon","clues":["Through them the Moon slowly brakes Earth’s spin, stretching the day by around two milliseconds per century.","Newton was first to explain them with gravity; Galileo had blamed Earth’s motion and got it wrong.","Most coasts get two a day because Earth rotates beneath a pair of ocean bulges.","Canada’s Bay of Fundy boasts the biggest recorded range, about 16 metres between low and high.","The sea creeps up the beach and slides back out twice a day. That rise and fall is this."],"fact":"The Moon drifts about 3.8 centimetres farther from Earth each year as the tides drain our planet’s spin."},{"id":"earthquake","answer":"Earthquake","display":"an earthquake","aliases":["earthquakes","quake","quakes"],"category":"phenomenon","clues":["The strongest ever recorded, magnitude 9.5 in Chile in 1960, set the whole planet ringing like a bell.","Japan’s huge 2011 event shifted Earth’s axis and trimmed the day by about 1.8 microseconds.","Each step on its magnitude scale means roughly 32 times more energy released.","‘Drop, cover, and hold on’ is the official advice for when one hits.","The ground shakes, dishes rattle, fault lines slip. Seismologists measure this."],"fact":"The Moon has them too: Apollo seismometers recorded ‘moonquakes’ that rumbled on for up to an hour."},{"id":"snow","answer":"Snow","display":"snow","aliases":["snowfall","snowflakes","snowflake"],"category":"phenomenon","clues":["Wilson Bentley photographed over 5,000 of its crystals from 1885 on, popularizing the idea that no two match.","It isn’t frozen rain: its six-sided crystals grow directly from vapour inside clouds.","Fresh drifts of it are mostly trapped air, which is why the world sounds so hushed after it falls.","Japan’s sport of Yukigassen turns throwing balls of it into a refereed competition.","This white winter precipitation makes men with carrot noses and days off school."],"fact":"The fear of snow has a name: chionophobia."},{"id":"gravity","answer":"Gravity","display":"gravity","aliases":["gravitation","the force of gravity"],"category":"phenomenon","clues":["It’s by far the weakest of nature’s four fundamental forces; a fridge magnet outpulls an entire planet.","It travels as ripples in spacetime; catching them in 2015 earned LIGO’s founders a Nobel Prize.","Einstein recast it not as a force at all, but as mass curving spacetime.","Legend says a falling apple set Newton thinking about it.","This invisible pull drops your toast butter-side down and keeps your feet on the floor."],"fact":"Aboard the space station it’s still about 90 per cent as strong as on the ground. Astronauts float because they’re falling."},{"id":"echo","answer":"Echo","display":"an echo","aliases":["echoes","echos","an echo"],"category":"phenomenon","clues":["To hear one distinctly, the reflecting wall must be at least about 17 metres away.","In Greek myth it’s all that remains of a nymph cursed to repeat other people’s last words.","Bats and dolphins hunt with it, reading returning clicks like sonar.","Amazon borrowed its name for a voice-activated smart speaker.","Shout ‘hello’ at a cliff and this bounces the greeting right back at you."],"fact":"The longest one ever measured rang for 112 seconds, inside a Scottish oil storage tank at Inchindown."},{"id":"mirage","answer":"Mirage","display":"a mirage","aliases":["mirages","fata morgana"],"category":"phenomenon","clues":["Ghost-ship legends like the Flying Dutchman may trace to one kind, named for the sorceress Morgan le Fay.","It’s no hallucination: cameras photograph it exactly as your eyes see it.","It appears when light bends through air layers of different temperatures, relocating a patch of sky.","Parched desert travellers chase the shimmering ‘water’ it paints on the sand.","The phantom puddle on a hot summer highway that vanishes as you approach is this optical illusion."],"fact":"Physicists sort mirages into ‘inferior’ and ‘superior’; the highway puddle is an inferior one."}]}