https://en.wikipedia.org/wiki/Slinky wrote:
<<A Slinky is a precompressed helical spring toy invented by Richard James in the early 1940s. It can perform a number of tricks, including travelling down a flight of steps end-over-end as it stretches and re-forms itself with the aid of gravity and its own momentum, or appear to levitate for a period of time after it has been dropped. In 1999, the United States Postal Service issued a Slinky postage stamp. The Slinky was inducted into the National Toy Hall of Fame in 2000 in their Celebrate the Century stamp series. A bill to nominate the slinky as the state toy of Pennsylvania was introduced by Richard Geist in 2001 but not enacted. The same year, Betty James was inducted into the Toy Industry Association's Hall of Fame. In 2003, Slinky was named to the Toy Industry Association's "Century of Toys List", a roll call of the 100 most memorable and most creative toys of the twentieth century.
Plastic Slinkys can be made in different colors. Many of them are made with the colors of the rainbow in rainbow order. They were marketed in the 1970s as a safer alternative to metal slinkys as they did not present a hazard when inserted into electrical sockets. The plastic spring toy, known as the Plastic Slinky was invented by Donald James Reum Sr. of Master Mark Plastics in Albany, Minnesota. Reum came up with the idea as he was playing with different techniques to produce a spiral hose for watering plants. However, as it came off the assembly line, according to his children, it looked more like a "Slinky." He worked at it until it came out perfectly and then went to Betty James with his prototype. Reum manufactured the Plastic Slinky for Betty James for several years. Eventually Betty James decided to manufacture the product exclusively through James manufacturing, effectively ending the production of the toy by the small Minnesota company. Reum's patent number, 4120929 was filed on Dec 28, 1976 and issued by the US Patent Office on Oct 17, 1978.
High school teachers and college professors have used Slinkys to simulate the properties of waves, and NASA has used them in zero-gravity physics experiments in the Space Shuttle. Slinkys and similar springs can be used to create a 'laser gun' like sound effect. This is done by holding up a slinky in the air and striking one end, resulting in a metallic tone which sharply lowers in pitch. The effect can be amplified by attaching a plastic cup to one end of the Slinky. In 1959, John Cage composed an avant garde work called Sounds of Venice scored for (among other things) a piano, a slab of marble and Venetian broom, a birdcage of canaries, and an amplified Slinky.
Metal Slinky can be used as an antenna - it resonates between 7 and 8 MHz. During Vietnam war it was used as a portable antenna for local HF communication. This setup had many advantages over a long wire shot from M79 grenade launcher: small dimensions, fast and quiet installation, reusability, good takeoff angle for local communication and good enough performance. It was also used to extend range of a handheld radio. Several online videos have shown the Slinky has been found to be act as an excellent squirrel deterrent for bird feeders when mounted on the pole of the bird feeder to prevent squirrels from climbing up the pole to reach the bird feeders.>>
The Helix Nebula from Blanco and Hubble
