Patents are the DNA of inventions, spawning entire new industries, businesses and economies. The giving away of patents by Toyota to spur development in hydrogen fuel, and by Tesla to help kickstart electric vehicle technology, are recent examples. A study by the Brookings Institution finds that the most productive periods in the United States occurred during the early 20th century and the Great Depression. The rate of patenting is nearly as high today as at any time in U.S. history. The most patents (per capita) came in 1916, 1915, 1885, 1932, 2010, 2011, 1931, 1883, 1890 and 1917. Here’s a look at some inventions from those years.
1883: Thomas Edison's Voltage Regulator
Superstar-inventor Thomas Edison has claimed more than 1,000 patents, including the phonograph, light bulb and this electronic device that was key to the development of radio, television and computer transistors.
Wikimedia Commons/Imperial War College
1885: Machine Gun
American-born British citizen Hiram Maxim invents a self-powered portable and fully-automatic machine gun that changes warfare. Its effects on society and the constitutional right to own it are still being debated today.
Thomas Kokta/Getty Images
1890: Stop Sign
William Phelps Eno proposed the first set of traffic rules and signs in an article in Rider and Driver, although the first actual sign didn’t appear until 1915.
1915: Stainless Steel Sink
The discovery of a new “rustless” steel by British metallurgist Harry Brearley is announced in the New York Times. Brearley applied for a patent that year, but American Elwood Haynes beat him to it. Its shiny surface, strength and corrosive resistant properties revolutionized modern industry from skyscrapers to kitchen utensils, trains and planes to medicine.
Jon Feingersh/Blend Images/Corbis
1916: Condenser Microphone
Edward C. Wente of New Jersey’s Bell Labs invents the electronic condenser microphone, which can be found today in recording, television, film and radio studios.
Jonathan Fife/Getty Images
1917: Modern Zipper
Gideon Sundback figures out that 10 fasteners per inch works much better than four and invents the modern zipper, or “separable fastener.” Used to close boots and tobacco pouches, the zipper doesn’t get into clothing for another 20 years.
1931: Stop-action Photography
Harold “Doc” Edgerton began playing around with strobe lighting while a grad student at MIT, developing both stop-action and ultra-high speed photography. His images of exploding bullets, running athletes and milk droplets became iconic photos. He went on to invent underwater time-lapse photography, atomic bomb timing and lights for copiers and flash photography.
Edwin Land invents the polarizer, which filters light waves and reduces glare. He goes on to invent instant photography, while the polarizer leads to sunglasses, camera filters and LCDs.
Paul Chinn/San Francisco Chronicle/Corbis
Apple debuted its iPad tablet in April 2010. Its history goes back to 1983, when Apple CEO Steve Jobs said he wanted to build a computer that users could carry around like a book, plug into telephone communications and link to libraries and other databases. It has been successful, kind of.
Perhaps someone should have realized that putting sharp metal teeth next to sensitive genitalia was a bad idea.
But since the zipper's invention in 1913, the device has proven immensely popular, replacing the button fly on most trousers, jeans and pants, for men as well as women.
And now we're paying the price for the zipper's speed and efficiency at the emergency room: According to a new study from the urology journal BJU International, an estimated 17,616 people went to the ER from 2002 to 2010 with genital injuries caused by zippers.
The overwhelming majority of those were penis-related injuries, though five reported injuries were to labia or vaginas, according to MinnPost.com. And the researchers estimated most of the penis injuries were to boys and teens younger than 18 (apparently, older men learn to avoid such trauma).
In fact, of all the ways a penis can be seriously hurt, zippers were the single leading cause of penile injuries requiring an ER visit, followed by bicycle injuries -- but only among adult men. (10 Wild Facts About the Male Body)
Among small boys, who apparently have the unfortunate habit of resting their penises on the lid of a toilet bowl, getting smashed by a falling toilet seat is more common than zipper injuries, according to NBC News. In a 2008 study, detailed in BJU International, scientists found that of four boys ages 2 to 4 who were treated for toilet-related penis injuries, three of the toddlers showed a build-up of fluid in the foreskin, but they were still able to urinate. The fourth had so-called glandular tenderness.
Permanent or serious damage to the penis from a zipper is rare, according to Herman Singh Bagga, a urology resident at the University of California, San Francisco and lead author of the study.
Mostly, "this is a pain issue," Bagga told NBC News. "It can completely ruin your night." In a few cases, however, zipper injuries have required surgical interventions, such as an unplanned circumcision.
In the event of a zipper-penis interaction, Bagga advises gently backing the zipper down. If that fails, Dr. Steven M. Selbst, professor of pediatrics at Jefferson Medical College in Philadelphia, advised pouring mineral oil over the snag.
"Be generous, that's the key," said Selbst, as quoted by the Huffington Post. "This is pretty cheap stuff. Then let the patient sit there for 20 or 30 minutes. When you come back, the foreskin will have simply slipped out of that zipper, although in some cases you may need a cotton swab to help it along a bit."
To avoid any cringe-inducing injuries in the first place, the UCSF researchers recommend men wear "form-fitting underwear," MinnPost.com reports. And parents should not put a boy into zippered trousers until he has the manual dexterity to avoid injuring himself.
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