is a coil
invented by mechanical engineer Richard James
in Philadelphia, Pennsylvania. It could go down stairs by walking "end-over-end". Slinkies come in various sizes. The shape is a simple helix
, or coil design, of a ribbon of material, originally metal
. The Slinky can "walk" down stairs as the coils stretch and reform as gravity
moves them down each step, the spring's momentum
causing it to spill end over end from one step to the next.
In 1943, Richard James
, a U.S. Naval engineer stationed at the Cramp shipyards in Philadelphia
, observed a torsion spring
fall off a table and roll around on the deck
(a torsion spring has no compression
). He told his wife Betty: "I think I can make a toy out of this."
With a US $500 loan, Richard designed a coiling mechanism and produced four hundred units of the toy. Betty James did some dictionary searching and she came up with the name "Slinky".
In November 1945, Richard and Betty James, through an arrangement with Gimbels in Philadelphia, were granted permission to set up an inclined plane in the toy department and demonstrate the spring's battery-less "walking" abilities. The toy was a hit, and the first 400 units were sold within 90 minutes.
In 1948 the company built a factory in Philadelphia, then later relocated to Hollidaysburg, Pennsylvania. As the company expanded, so did the product line. New Slinky toys, including Slinky Jr. and the Slinky Dog, were developed while non-coiled toys such as building kits were added to the inventory. However, Slinky has remained the core product of James Industries.
Commercials for the Slinky featured the memorable jingle: "It's Slinky, it's Slinky, for fun it's a wonderful toy. It's Slinky, it's Slinky, it's fun for a girl and a boy."
During the Vietnam War, Slinkys were also used as mobile radio antennas.
The Slinky (under House Bill No.1893 - Session 2001, of the General Assembly of Pennsylvania) has been named the Official State Toy of Pennsylvania as of November 4, 2001.
In 2003, James Industries merged with Poof Products to create Poof-Slinky Inc.
Use in science education
Besides being a toy, the Slinky can be used to help explain scientific concepts. By moving the ends of a stretched Slinky side to side transverse wave motion
can be demonstrated. Pinching several coils of a stretched Slinky together and suddenly letting go creates a traveling longitudinal (compressional) wave, analogous to a sound wave, which will reflect off of each end. By twisting one end of a stretched Slinky and releasing it suddenly, a torsional (shear) wave is set up which will reflect off of the Slinky's ends. These demonstrations can be especially useful in teaching acoustics
One or more Slinkys used together can form the basis of a shortwave radio antenna. Amateur radio operators have even used them as transmitting antennas.
The Slinky can also be used in physics experiments as a solenoid to induce a magnetic field, and to explore the factors that affect a magnetic field inside a solenoid.
In Popular Culture
- The Slinky Dog also appears in Disney/Pixar's Toy Story 1 and 2.
- The Slinky's jingle was borrowed for some early TV ads for the Isuzu MU Wizard, when the model was called Amigo. The driver and passengers sang: "Amigo, Amigo, it's fun for a girl and a boy!"
- In the Futurama episode "Bendless Love", Dr. Zoidberg is horrified when Bender straightens out his "cuddly pet Slinky" into a long, arrow-straight piece of metallic wire. Zoidberg later tries to bend it back into its original form, with downright spectacularly little success, to the point of it bursting into flame for no apparent reason after being pushed down stairs.
- The jingle was also parodied on The Ren and Stimpy Show in a fake commercial for a fictional toy called Log. The lyrics, sung to a similar tune as the Slinky jingle, were "''It's Lo-og, it's Lo-og, it's big, it's heavy, it's wood! It's Lo-og, it's Lo-og, it's better than bad, it's good!"
- The Christian band Lost and Found uses a Slinky as one of their major instruments. It is featured in their song titled "Lions".
- The film Ace Ventura: When Nature Calls features a scene in which Ace lets a Slinky crawl down a monolithic set of steps going up a mountainside to a Tibetan monastery, only have the Slinky stop at the next-to-last step.
- In the film Ghostbusters II, Ray asks Egon, "You mean, you never even had a Slinky?" to which Egon replies, "We had part of a Slinky. But I straightened it.
- In the film Lords of Dogtown, Jay Adams is asked to participate in a Slinky ad. He tries singing the jingle, but refuses.
- In one of the Calvin and Hobbes Sunday strips, Calvin asks his dad that he know what would make the house a lot better. Dad then says "No, what?" Calvin tells him he should take out the stairs and put in an elevator. Dad replies "Good. I'll file that with your idea for the moving sidewalk. After that, Calvin was on the staircase and goes downstairs by walking "end-over-end" like a Slinky does. His mom came, terrified, saying "Did you fall down the stairs again?!" Calvin then utters "That's me (oof), the human Slinky."