Twenty questions about inventions and the people behind them, from everyday objects to world-changing machines, each with the story behind the answer. Play them as a quiz, or read the list with the answers marked.
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The same questions as the quiz, right answer highlighted and the fact under it. Print the page for a quiz night: the print layout keeps the questions and answers only. The Inventions topic in Lock&Learn holds 113 facts in all.
What everyday fastener went ten years without its own name?
The zipper wasn't even called a zipper for its first decade. Gideon Sundback patented his practical slide fastener in 1913, but it was called a "hookless fastener." B.F. Goodrich only coined the name "zipper" in 1923 for the sound it made closing rubber boots, and the catchy name stuck to everything with teeth and a slider.
Source: National Inventors Hall of Fame
Who patented a clothing-closure idea in 1851 and then just... shelved it?
A sewing machine legend patented a proto-zipper decades early. Elias Howe, famous for the sewing machine, patented an "Automatic, Continuous Clothing Closure" back in 1851. He never developed or marketed it, leaving the door open for Whitcomb Judson's clasp locker decades later.
Source: History Cooperative
What everyday closure sat in shoes and tobacco pouches for 20 years before reaching trousers?
Zippers took nearly two decades to sneak into everyday clothes. Even after Gideon Sundback perfected the modern slide fastener in 1913, it was mostly used on boots and tobacco pouches. It wasn't until the 1930s that designers began stitching zippers into mainstream trousers and dresses.
Source: History Cooperative
Which classic denim brand resisted the zipper for over a century?
Levi's held out on the button fly until 1954. Levi Strauss & Co. stuck with button flies on its 501 jeans for decades. In 1954 it finally launched the 501Z, a zipper-fly version aimed at East Coast customers who found buttons old-fashioned.
Source: Levi Strauss & Co.
How did the pencil get its wooden coat in the 1560s?
The first wood-cased pencil was a hollowed-out juniper stick. After a huge graphite deposit was found in England's Lake District, Italian couple Simonio and Lyndiana Bernacotti hollowed out a juniper stick, slid a graphite rod inside, and shaped it into an oval so it wouldn't roll off the table.
Source: Pencils.com
What writing tool got its most famous nickname completely wrong?
Pencil "lead" has never contained a speck of lead. Early Europeans mistook graphite for a form of lead, so the name stuck even after chemists proved it was pure carbon. In 1795, Nicolas-Jacques Conte started mixing powdered graphite with clay to make the cores pencils still use today.
Source: Wikipedia
Why do so many pencils share the exact same yellow paint job?
Yellow pencils began as a nod to prized Asian graphite. Pencils turned yellow thanks to a Czech marketing idea, not an American one. In 1889 the L. & C. Hardtmuth company launched its Koh-I-Noor pencils painted yellow to signal prized Asian graphite and Chinese associations with the colour. US makers such as Dixon Ticonderoga only copied the trend later, around 1913.
Source: Reader's Digest
How much can a single pencil actually write before it runs out?
One pencil can write roughly 45,000 words. A standard pencil holds enough graphite to write about 45,000 words. The oft-repeated claim that it can draw a 35-mile line is a myth; real tests put an unbroken line closer to three or four miles.
Source: Reader's Digest
What kitchen gadget launched at $495 in 1967, roughly $5,000 today?
The first home microwave cost about as much as a used car. In 1967, Amana released the countertop Radarange, the first microwave oven small and affordable enough for a home kitchen. It still cost $495, equivalent to around $5,000 today, and could cook a hamburger in about 35 seconds.
Source: Smithsonian Magazine
What kitchen appliance debuted the size of a refrigerator, not a countertop?
The first microwave ovens stood six feet tall and weighed 750 pounds. Raytheon's first commercial microwave, the 1947 Radarange, was a hulking six-foot-tall unit weighing 750 pounds and costing thousands of dollars. It was built for restaurants and ships, not home kitchens.
Source: History.com
What kitchen appliance went from a rare luxury to a near-universal fixture in just one generation?
Microwaves went from rare to nearly universal in 30 years. In 1971, fewer than 1% of American households owned a microwave oven. By 1986 that figure had climbed to about a quarter, and by 1997 it had rocketed past 90%, making it one of the fastest-adopted kitchen appliances ever.
Source: Smithsonian Magazine
Whose frequent kitchen mishaps led directly to a medicine-cabinet staple?
The Band-Aid was invented for one especially clumsy cook. In 1920, Johnson & Johnson employee Earle Dickson kept treating his wife Josephine's small kitchen cuts and burns with bulky gauze and tape. So he pre-assembled strips of gauze and adhesive tape she could cut and apply herself, creating the first self-adhesive bandage.
Source: Smithsonian Magazine
What now-ubiquitous bandage sold a mere $3,000 worth in its debut year?
The Band-Aid nearly flopped in its very first year. When Johnson & Johnson launched the Band-Aid in 1921, sales limped along to just $3,000 in the first year. The turnaround came when the company began handing out free bandages to Boy Scout troops nationwide, sparking demand.
Source: Fox News
How many Band-Aids has the world bought since the brand launched in 1921?
Over 100 billion Band-Aids have been sold worldwide. Johnson & Johnson estimates it has sold more than 100 billion Band-Aid brand bandages since the product launched in 1921. The name became so common that it's now used generically for any adhesive bandage.
Source: Wikipedia
How far did a homemade kitchen fix carry its creator up the corporate ladder?
The Band-Aid's inventor rose from cotton buyer to company vice president. Earle Dickson worked as a cotton buyer at Johnson & Johnson when he invented the Band-Aid for his wife. His simple fix was such a success that the company later made him a vice president, a role he held until retiring in 1957.
Source: Fox News
What ancient Egyptian recipe cleaned teeth thousands of years before modern toothpaste?
The oldest toothpaste recipe calls for iris flowers and pepper. A papyrus from ancient Egypt records a tooth-cleaning powder made from crushed rock salt, mint, dried iris flower, and pepper. It's considered the oldest known written toothpaste formula, and dentists who've recreated it say it actually worked.
Source: Open Culture
What packaging switch in the 1890s changed how the whole world brushes its teeth?
Toothpaste used to be sold in jars, not tubes. Colgate began mass-producing toothpaste in 1873, but customers scooped it out of jars with their fingers. Inspired by artists' paint tubes, the company started selling toothpaste in a squeezable metal tube in 1896.
Source: Colgate
What cavity-fighting ingredient took decades of lab work before hitting store shelves?
The world's first fluoride toothpaste didn't launch until 1955. After years of research into stannous fluoride's ability to strengthen enamel, Procter & Gamble launched Crest in 1955 as the world's first fluoride toothpaste. Its cavity-fighting claims were later validated by the American Dental Association.
Source: National Inventors Hall of Fame
What were the very first coins in the world actually made of?
The world's first coins were stamped lumps of gold and silver. In the ancient kingdom of Lydia, around 600 BC, rulers began stamping lumps of electrum, a natural gold-silver alloy, with an official mark like a lion. That stamp let merchants trust the metal's weight and purity without weighing it every time, creating the first true coins.
Source: World History Encyclopedia
What currency is too heavy to ever change hands when you spend it?
Some money on one Pacific island weighs four tons. On the island of Yap in Micronesia, giant carved limestone discs called rai stones served as high-value currency, with the largest examples measuring 12 feet across and weighing up to 4,000 kilograms. Owners rarely moved the stones at all; everyone simply agreed on who owned which one.
Source: Wikipedia
This page has 20, each with three answers and the fact that settles it. They are the first 20 of the 113 facts in the Inventions topic of Lock&Learn, which holds the rest.
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