slinky

In 1943, Richard T. James, a naval mechanical engineer, observed a spring "stepping" downward after being knocked off a shelf, then coming to rest in a vertical position.{{cite web |url=http://web.mit.edu/Invent/iow/slinky.html |title=Inventor of the Week: The Slinky |publisher=MIT School of Engineering |access-date=February 24, 2009 |archive-url=https://web.archive.org/web/20090222210634/http://web.mit.edu/Invent/iow/slinky.html |archive-date=February 22, 2009}} James's wife Betty later recalled, "He came home and said, 'I think if I got the right property of steel and the right tension, I could make it walk.'"{{cite news |title=Novel Ideas |first=John |last=Przybys |url=http://www.reviewjournal.com/lvrj_home/1998/Mar-01-Sun-1998/lifestyles/7021869.html |url-status=deviated |archive-url=https://web.archive.org/web/20031026221441/http://www.reviewjournal.com/lvrj_home/1998/Mar-01-Sun-1998/lifestyles/7021869.html |archive-date=October 26, 2003 |newspaper=Las Vegas Review-Journal |date=March 1, 1998 |access-date=February 21, 2024}}{{cbignore}} James experimented with different types of steel wire over the next year, and finally found a spring that would "walk". Betty was skeptical, but changed her mind when the toy was fine-tuned and neighborhood children expressed an excited interest in it.

Richard and Betty formed James Industries and began manufacturing slinkys in Clifton Heights, Pennsylvania, selling them for $1 each. They were {{convert|2+1/2|in}} tall, and included 98 coils of high-grade blue-black Swedish steel. They initially had difficulty selling Slinky to toy stores, but in 1945, they were granted permission to set up an inclined plane in the toy section of Gimbels Department Store in Philadelphia to demonstrate it on the Tuesday after Thanksgiving. It was an instant hit; the first 400 units were sold in 90 minutes.{{cite book |last=Rich |first=Mark |title=Warman's 101 Greatest Baby Boomer Toys |publisher=KP Books |year=2005 |location=Iola, Wisconsin |pages=58–59 |isbn=0-89689-220-4}} In 1946, Slinky was introduced at the American Toy Fair.{{cn|date=October 2024}}

The Slinky was originally priced at $1, but many paid much more due to price increases of spring steel in Pennsylvania. It has, however, remained modestly priced throughout its history as a result of Betty James' concern about the toy's affordability for less affluent customers. In addition to its use as a toy, it has been used as a classroom teaching tool; as a portable and extendable radio antenna in wartime (particularly the Vietnam War).{{Cite web|url=https://www.smithsonianmag.com/innovation/accidental-invention-slinky-180973016/|title = The Accidental Invention of the Slinky}} It was inducted into the National Toy Hall of Fame at The Strong in Rochester, New York in 2000. In 2003, it was named to the Toy Industry Association's Century of Toys List.{{cite press release |url=http://www.toy-tia.org/industry/news/press/tf03_centuryoftoys.html |archive-url=https://web.archive.org/web/20030401214230/http://www.toy-tia.org/industry/news/press/tf03_centuryoftoys.html |archive-date=April 1, 2003 |date=January 20, 2003 |title=Toy Industry Association Announces Its 'Century of Toys List' | publisher=Toy Industry Association}} In its first 60 years, about 300 million Slinkys were sold.{{cite magazine|title=How the Slinky Sprang Into Stores 70 Years Ago |url=https://time.com/4127170/slinky-70-years/ |date=November 27, 2015 |magazine=Time |first=Merrill |last=Fabry |access-date=January 3, 2018}}

In 1960, after his wife filed for divorce, Richard James left the company and he became an evangelical missionary in Bolivia with Wycliffe Bible Translators.{{Cite web|title='Slinky' brainchild |newspaper=Delaware County Daily Times |date=November 25, 1976 |url=https://www.newspapers.com/newspage/19524766/ |access-date=January 25, 2014}} Betty James moved the company to Hollidaysburg, Pennsylvania in 1964 and the company grew under her direction. She attributed the toy's success to its "simplicity".{{cite news |title=Betty James, who cofounded Slinky company, dies |url=http://www.kxmb.com/getArticle.asp?ArticleId=300881 |access-date=February 25, 2009|date=November 22, 2008|agency=Associated Press|publisher=KXMB-TV}} The company was sold to Poof Products, Inc. in 1998. Slinky continued production in Hollidaysburg.

Betty James died of congestive heart failure in November 2008, at age 90, after serving as James Industries' president from 1960 to 1998.{{cite news |title=Betty James, Who Named the Slinky Toy, Is Dead at 90 |url=https://www.nytimes.com/2008/11/25/business/25james.html |access-date=February 25, 2009|last=Hevesi|first= Dennis|newspaper=The New York Times | date=November 25, 2008}}

In July 2012, Poof-Slinky, Inc. was acquired by the private equity firm Propel Equity Partners.{{Cite web |date=May 28, 2013 |title=Propel Equity Partners Acquires ALEX® |url=https://www.businesswire.com/news/home/20130528005951/en/Propel-Equity-Partners-Acquires-ALEX%C2%AE |access-date=January 22, 2023 |website=www.businesswire.com |language=en}} In 2014, Propel Equity Partners consolidated Poof-Slinky and several other toy brands into Alex Brands.{{Cite web |date=January 29, 2014 |title=ALEX TOYS®, POOF-SLINKY® and ZOOB® Come Together Under New Collective Brand Identity |url=https://www.businesswire.com/news/home/20140129005283/en/ALEX-TOYS%C2%AE-POOF-SLINKY%C2%AE-and-ZOOB%C2%AE-Come-Together-Under-New-Collective-Brand-Identity |access-date=January 22, 2023 |website=www.businesswire.com |language=en}}

In July 2020, the Slinky brand was sold to Just Play.{{Cite web|url=https://www.licenseglobal.com/toys-games/just-play-acquires-slinky-and-shrinky-dinks-brands|title = Just Play Acquires the Slinky and Shrinky Dinks Brands|date = July 2020}}

The rules that govern the mechanics of a Slinky are Hooke's law and the effects of gravitation.{{cn|date=October 2024}}

The oscillation of a vertically suspended Slinky has the periodic duration{{Cite journal |last=Pretz |first=Jörg |date=July 1, 2021 |title=Oscillations of a suspended slinky |url=https://iopscience.iop.org/article/10.1088/1361-6404/abcddf |journal=European Journal of Physics |volume=42 |issue=4 |pages=045008 |doi=10.1088/1361-6404/abcddf |arxiv=2005.12203 |bibcode=2021EJPh...42d5008P |s2cid=218869730 |issn=0143-0807}}

$T\; =\; \backslash sqrt\{\backslash frac\{32\; L\}\{g\}\}\; \backslash ,\; ,$

where $L$ is the length of the Slinky in the gravitational field of the Earth and $g$ the acceleration due to gravity $g=9.81\; \backslash ,\backslash mathrm\{m/s\}^2$. Please note, that the expression for $T$ is independent of the spring constant $k$ and the mass $m$ of the Slinky. For a spring pendulum one would expect such a dependence. This is because the dependence on $k$ and $m$ is hidden in the length $L(k,m)$:

$L(k,m)\; =\; \backslash frac\{mg\}\{2k\}\; =\; \backslash frac\{W\}\{2k\}\backslash ,\; ,$

this allows one to write:

$T\; =\; 4\; \backslash sqrt\{\backslash frac\{m\}\{k\}\}\; \backslash ,\; .$

This expression differs from the ordinary spring pendulum

$T\_\{\backslash mbox\{spring\; pendulum\}\}\; =\; 2\backslash pi\; \backslash sqrt\{\backslash frac\{m\}\{k\}\}\; \backslash ,\; ,$

because for the spring pendulum one assumes a massless spring with a mass $m$ attached at the bottom.

When set in motion on a stepped platform such as a stairway, the Slinky transfers energy along its length in a longitudinal wave. The whole spring descends end over end in a periodical motion as if it were "walking" down one step at a time.Ikenson, Ben. Patents: Ingenious Inventions: How They Work and How They Came to Be.

When the top end of the Slinky is dropped, the information of the tension change must propagate to the bottom end before both sides begin to fall; the top of an extended Slinky will drop while the bottom initially remains in its original position, compressing the spring.{{cite AV media | url=http://blogs.discovermagazine.com/badastronomy/2011/09/26/slinky-drop-physics/ | title=Slinky drop physics - video of extended Slinky being dropped | magazine=Discover magazine | date=September 26, 2011}} This creates a suspension time of ~0.3 s for an original Slinky,{{cite journal|title=Modeling a falling slinky|arxiv=1208.4629|last=Cross|first=Rod C.|author2=Wheatland, Mike S. |date=August 22, 2012|doi=10.1119/1.4750489|volume=80|issue=12|journal=American Journal of Physics|page=1051|bibcode=2012AmJPh..80.1051C|s2cid=33704140}}{{cite journal|last=Cross|first=Rod C.|author2=Wheatland, Mike S. |title=Modeling a falling slinky|journal=American Journal of Physics|year=2012|volume=80|issue=12|pages=1051|doi=10.1119/1.4750489|publisher=American Association of Physics Teachers|arxiv=1208.4629|bibcode=2012AmJPh..80.1051C|s2cid=33704140}} but has potential to create a much larger suspension time.

A suspended Slinky's center of mass is accelerating downward at 1g (about {{Convert|32|ft/s2|m/s2|abbr=out|disp=or}}); when released{{snd}}the lower portion moves up toward the top portion with an equivalent, constant upward acceleration as the tension is relieved. As the spring contracts, every point along its length will accelerate downward with gravity and tension, and experience a decrease in overall downward acceleration related to height along the spring due to the spring force changing with extension{{snd}}at the bottom of the spring the upward initial acceleration reduces in accordance with Hooke's law as the spring contracts, but the centre toward which it is moving gets closer{{snd}}meaning the base will have been displaced sufficiently toward the centre of inertial mass for it to appear to have hung still. Should this phenomenology extend to very light strings with heavy suspended masses (which have approximately linear tension distributions), different mathematics would be needed to explain the phenomenon.{{cn|date=October 2024}}

The jingle for the Slinky television commercial was created in Columbia, South Carolina in 1962 with Johnny McCullough and Homer Fesperman writing the music and Charles Weagly penning the lyrics. It became the longest-running jingle in advertising history.{{cite book | last = Walsh | first = Tim | year = 2005 | title = Timeless Toys: Classic Toys and the Playmakers Who Created Them | publisher = Andrews McMeel Publishing | isbn = 978-0-7407-5571-2 | pages = 62–65}}

The jingle has itself been parodied and referenced in popular culture. It is seen in the "Log" commercial on The Ren & Stimpy Show and sung by actor Jim Carrey in Ace Ventura: When Nature Calls. It is also referenced in the movie Lords of Dogtown, where it is sung in full by Emile Hirsch, and is sung by Eddie Murphy as part of the final routine in the stand-up comedy film Eddie Murphy Raw. It was also parodied in an ad for the Isuzu Amigo used as a promo for the vehicle's return in late March 1998, nearly two months before the ad was pulled due to criticism from the company that made the Slinky.{{cite magazine | last = Halliday | first = Jean | date = May 18, 1998 | url = https://adage.com/article/news/isuzu-pulls-commercial-parodied-slinky-ads-intro-tv-spot-amigo-suv-drew-criticism-marketer-flight/65788 |url-access=subscription |archive-url=https://web.archive.org/web/20230226171042/https://adage.com/article/news/isuzu-pulls-commercial-parodied-slinky-ads-intro-tv-spot-amigo-suv-drew-criticism-marketer-flight/65788 |archive-date=February 26, 2023 |title = Isuzu Pulls Commercial That Parodies Slinky Ads: Intro TV Spot for Amigo SUV Drew Criticism; Marketer Says Flight Was Over |magazine=Ad Age |publisher=Crain Communications |access-date=February 10, 2024}}{{cbignore}}

{{Redirect|Slinky Dog|the character in Toy Story|List of Toy Story characters#Slinky Dog}}

Early in the history of James Industries, Helen Herrick Malsed of Washington state sent the company a letter and drawings for developing Slinky pull-toys. The company liked her ideas, and Slinky Dog and Slinky Train were added to the company's product line. Slinky Dog, a small plastic dog whose front and rear ends were joined by a metal Slinky, debuted in 1952. Malsed received royalties of $60,000 to $70,000 annually for 17 years on her patent for the Slinky pull-toy idea, but never visited the plant.{{cite news |last=McDowell |first=Edwin |title=Helen H. Malsed, 88, Creator of Slinky Toys |newspaper=The New York Times |date=November 28, 1998 |url=https://query.nytimes.com/gst/fullpage.html?res=9E03E3DB1139F93AA15752C1A96E958260 |url-access=subscription |archive-url=https://web.archive.org/web/20160824221309/http://www.nytimes.com/1998/11/29/business/helen-h-malsed-88-creator-of-slinky-toys.html |archive-date=August 24, 2016 |access-date=February 26, 2009}}

In 1995, the Slinky Dog (voiced by Jim Varney and Blake Clark) was redesigned for all of Pixar's Toy Story movies. James Industries had discontinued their Slinky Dog a few years previously. Betty James approved of the new Slinky Dog, telling the press, "The earlier Slinky Dog wasn't nearly as cute as this one."{{cite news |last=Witchel |first=Alex |date=February 21, 1996 |title=Talking Toys with Betty James; Persevering for Family and Slinky |newspaper=The New York Times |url=https://query.nytimes.com/gst/fullpage.html?res=9C00E1D61339F932A15751C0A960958260 |access-date=February 26, 2009}}

File:Slinky rainbow.jpg

Plastic Slinkys are also available. They 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 of Avon Plastics in Albany, Minnesota. Reum came up with the idea as he was experimenting 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 December 28, 1976, and issued by the U.S. Patent Office on October 17, 1978.{{cite patent | country = US | number = 4120929 | status = patent | fdate = December 28, 1976 | gdate = October 17, 1978 | title = Method for producing a spirally wound plastic article | invent1 = Reum, Donald James}}

In 1999, the United States Postal Service issued a Slinky postage stamp.{{cite book |title=Sourcebook for Receptive and Expressive Language |publisher=Wayne State University Press |location=Detroit, Michigan |year=2006 |page=106 |isbn=0-8143-3314-1 |url=https://books.google.com/books?id=qO0s0Z52IYYC&q=Slinky+postage+stamp&pg=PA106 |access-date=February 25, 2009}} 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.{{cite web|url=http://www.legis.state.pa.us/cfdocs/billinfo/billinfo.cfm?syear=2001&sind=0&body=H&type=B&BN=1893|title=Regular Session 2001–2002, House Bill 1893|publisher=Pennsylvania General Assembly|access-date=March 31, 2011}} 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" of the 20th century's 100 most memorable and creative toys.{{cite press release |title=Toy Industry Association Announces Its Century of Toys List |publisher=Business Wire for Toy Industry Association |date=January 21, 2003 |url=http://www.allbusiness.com/manufacturing/miscellaneous-mfg-doll-toy-games-games/5673984-1.html |access-date=February 19, 2009}}

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, causing a metallic sound that sharply lowers in pitch. The effect can be amplified by attaching a plastic cup to one end of the Slinky.{{cite web|url=http://www.abc.net.au/science/experimentals/experiments/episode19_2.htm|title=the experiMENTALS: experiments - laser canon sound effect - The Lab - Australian Broadcasting Corporation's Gateway to Science|website=www.abc.net.au|access-date=February 19, 2018}}

The Helixophone is the name composer and artist Sonia Paço-Rocchia gave to a musical instrument made with a Slinky and a resonator. Hélix is a sound installation with up to 20 Helixophones, automated and playing an interactive sound composition.{{cite web|access-date=March 10, 2021|language=fr-CA|title=Sonia Paço-Rocchia - Helix - Exposition à Victoriaville – Le Carré 150|url=https://www.lecarre150.com/expoarchives/detail/Sonia-Paco-Rocchia/Helix/15-05-2017-10-00|website=www.lecarre150.com}}{{cite web|access-date=March 10, 2021|language=fr-ca|last=Sara|title=2017|url=https://www.fimav.qc.ca/fr/2017|website=fimav.qc.ca|date=December 16, 2015 }}{{cite web|access-date=March 10, 2021|date=January 9, 2018|first=Sophie|language=fr-FR|last=Poisson|title=Rebondir|url=https://journalmetro.com/local/verdun/1337751/rebondir/|website=Journal Métro}}{{cite web|access-date=March 10, 2021|language=fr|title=ICI Radio-Canada Première {{!}} Balados, livres audio|url=http://ici.radio-canada.ca/premiere/emissions/bon-pied-bonne-heure/segments/entrevue/85115/phos-installation-matane-sonia-paco-rocchia-sonore-interactive-helix|website=Radio-Canada}}{{cite web|access-date=March 10, 2021|author=Radio-Canada: Ici Alberta|language=fr|title=Hélix au Centre d'arts visuels de l'Alberta|website=Facebook |url=https://www.facebook.com/icialberta/videos/1936501479705990/}}

Metal Slinkys can be used as an antenna; it resonates between 7 and 8 MHz. During the 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 adequate performance. It was also used to extend the ranges of handheld radios.{{cite book|title=Last-Minute Survival Secrets: 128 Ingenious Tips to Endure the Coming Apocalypse and Other Minor Inconveniences|year=2015|publisher=Chicago Review Press, Incorporated|url=https://archive.org/details/lastminutesurviv00gree|url-access=registration|page=[https://archive.org/details/lastminutesurviv00gree/page/24 24]|isbn=9781613749852}}

In 1985, in conjunction with the Johnson Space Center and the Houston Museum of Natural Science, Space Shuttle Discovery astronauts created a video demonstrating how familiar toys behaved in space. One astronaut described the toy as "sort of droop[ing]". The video was prepared to stimulate interest in school children about the basic principles of physics and the phenomenon of weightlessness.{{cite news |title=Toy Time in Space |newspaper=The New York Times |date=April 16, 1985 |url=https://query.nytimes.com/gst/fullpage.html?sec=health&res=9B07E3DC1239F935A25757C0A963948260 |url-access=subscription |archive-url=https://web.archive.org/web/20121110092247/http://www.nytimes.com/1985/04/16/science/toy-time-in-space.html |archive-date=November 10, 2012 |access-date=February 26, 2009}}{{cbignore}}

Several online videos have shown that a Slinky can be mounted on the pole of a bird feeder to deter squirrels from climbing up the pole.{{Cite web|url=https://abc13.com/society/slinky-used-to-keep-squirrels-away/1667062/|title=Woman uses Slinky to keep squirrels from bird feeder|date=December 21, 2016}}

• Spring (device) § Classification

{{refs}}

{{commonscat}}

• {{Official website|https://justplayproducts.com/brands/slinky/|Just Play}}
• {{Official website|https://web.archive.org/web/20050216012555/http://www.poof-slinky.com/|Poof-Slinky, Inc}} (archive)
• [http://sydney.edu.au/news/84.html?newsstoryid=10758 University of Sydney] - home institution of Slinky physics researchers

{{Authority control}}

Category:Educational toys

Category:Metal toys

Category:Toy companies of the United States

Category:Springs (mechanical)

Category:1940s toys

Category:1950s toys

Category:1960s toys

Category:Products introduced in 1945

Category:Goods manufactured in the United States