> Which children's toy can be described as, "a pre-compressed, helical spring?"And the answer: the slinky. Photo courtesy: Fox Photos / Getty Images.Invented by Richard T. James, theSlinky made its debut in 1945 at Gimbels department store in Philadelphia. Bythe end of the 20th century, more than 250 million Slinkys had been soldworldwide.This iconic toy has an origin story unique in its own right: the Slinky existstoday because of a simple accident. While mechanic Richard James was designingan apparatus to stabilize maritime instruments for the U.S. Navy, he knocked abox of spare parts off the shelf. Among them was a coiled piece of wire, whichseemed to miraculously "step" down from his desk to the ground. As inventorsoften do, James had a quintessential following thought: "I should make achildren's toy out of this."In the two years that followed, James perfected the toy. With help from his wifeBetty, who is said to have flipped through a dictionary to land on the name"Slinky," the product hit the shelves with little ado. After an unsuccessful fewweeks, James took the matter into his own hands. The inventor staged ademonstration of the toy's ability to "walk," and presto! Within the first 90minutes of his demo, he had sold 400 Slinkys. By the end of the 1945 holidayseason, customers had snatched up nearly 20,000 Slinkys for a dollar each. Thetoy quickly inserted itself into the hearts of the American people. When the Slinky was inducted into the National Toy Hall of Fame in 2000, morethan 250 million had been sold to date. It remains a popular and well-loved toyfor children across the world. Check out this Smithsonian article[https://www.smithsonianmag.com/innovation/accidental-invention-slinky-180973016/] to read more. And now, a joke: When is the best time to wash a stinky Slinky?And the answer: Spring cleaning!