Examine individual changes

'{{short description|Ball used in cue sports}} {{redirect|Cue ball|the video game|Jimmy White's 2: Cueball|things called "Q-ball"|Q-ball (disambiguation)}} {{Use dmy dates|date=October 2012}} [[File:Billiard ball comparison.jpg|thumb|200px|{{Cuegloss|Cue ball|Cue balls}} from (left to right): {{unordered list | [[Russian pyramid]] and [[Kaisa (billiards)|kaisa]]—68&nbsp;mm ({{frac|2|11|16}}&nbsp;in) | [[Carom billiards|Carom]]—61.5&nbsp;mm ({{frac|2|7|16}}&nbsp;in) | International [[pool (cue sports)|pool]]—57.15&nbsp;mm ({{frac|2|1|4}}&nbsp;in) | [[Blackball (pool)|British-style]] pool (large) —56&nbsp;mm ({{frac|2|3|16}}&nbsp;in) | [[Snooker]]—52.5&nbsp;mm ({{frac|2|1|15}}&nbsp;in) | British-style pool (regular)—51&nbsp;mm (2&nbsp;in) }} Not shown: miniature pool—approximately 38&nbsp;mm ({{frac|1|1|2}}&nbsp;in).]] A '''billiard ball''' is a small, hard [[ball]] used in [[cue sports]], such as [[carom billiards]], [[Pool (cue sports)|pool]], and [[snooker]]. The number, type, diameter, color, and pattern of the balls differ depending upon the specific game being played. Various particular ball properties such as [[hardness]], [[friction coefficient]] and [[Resilience (materials science)|resilience]] are important to accuracy. ==History== [[File:US114945 - Patents for Injection Moulding by John Wesley Hyatt (Diagram 1).png|thumb|[[John Wesley Hyatt|Hyatt]]'s celluloid ball patent (1871)]] Early balls were made of various materials, including wood and clay (the latter remaining in use well into the 20th century). Although affordable [[ox]]-bone balls were in common use in Europe,<ref name="ebay">Note: Antique ox-bone balls remain a very common item on [[eBay]].</ref> elephant [[ivory]] was favored since at least 1627 until the early 20th century;<ref name="Shamos 1999">{{Shamos 1999}}</ref>{{rp|17}} the earliest known written reference to ivory billiard balls is in the 1588 inventory of the [[Duke of Norfolk]].<ref name="Everton 1986">{{Cite book |title=The History of Snooker and Billiards |last=Everton |first=Clive |authorlink=Clive Everton |location=Haywards Heath, UK |publisher=[[Transworld (company)|Partridge Pr.]] ננננננננננננננננ |year=1986 |isbn=1-85225-013-5 |edition=rev. ver. of ''The Story of Billiards and Snooker'', 1979 |quote=11 balls of {{sic|hide=y|yvery}} }}</ref> Dyed and numbered balls appeared around the early 1770s.<ref name="Shamos 1999" />{{rp|17}} By the mid-19th century, elephants were being slaughtered for their ivory at an alarming rate, just to keep up with the demand for high-end billiard balls – no more than eight balls could be made from a single elephant's tusks.{{citation needed|date=February 2010|reason=When sourced, this should probably be added to the article on elephants.}} The billiard industry realized that the supply of elephants (their primary source of ivory) was [[endangered species|endangered]], as well as dangerous to obtain (the latter an issue of notable public concern at the turn of the 19th century).<ref name="Shamos 1999" />{{rp|17}} Inventors were challenged to come up with an alternative material that could be [[Manufacturing|manufactured]], with a [[United States dollar|US$]]10,000 prize being offered by a New York supplier,<ref name="Shamos 1999" />{{rp|17}} [[Michael Phelan (billiards)|Phelan]] and [[H. W. Collender|Collender]].{{Citation needed|date=February 2010|reason=Can't find reliable source for company name.}} (This would be worth approximately ${{formatnum:{{Inflation|US|10000|1869|r=1}}}} in {{CURRENTYEAR}}{{Inflation-fn|US}}.) Although not the first artificial substance to be used for the balls (e.g. [[Sorel cement]], invented in 1867, was marketed as an artificial ivory), [[John Wesley Hyatt]] invented a composition material in 1869 called [[nitrocellulose]] for billiard balls (US patent 50359, the first American patent for billiard balls). It is unclear if the cash prize was ever awarded<!--to anyone, that is-->, and there is no evidence suggesting he did in fact win it.<ref name="Shamos 1999" />{{rp|17}}<ref name="Plastiquarian">{{cite web |url=http://www.plastiquarian.com/hyatt.htm |title=Hyatt |author= |year=2002 |work=Plastiquarian.com |location=London |publisher=[[Plastics Historical Society]] |accessdate=26 February 2008 |deadurl=yes |archiveurl=https://web.archive.org/web/20071221114457/http://www.plastiquarian.com/hyatt.htm |archivedate=21 December 2007 |df=dmy }}</ref> By 1870 it was commercially branded [[Celluloid]], the first industrial plastic. However, the nature of celluloid made it volatile in production, occasionally exploding, which ultimately made this early plastic impractical.<ref name="Shamos 1999" />{{rp|17}} Subsequently, to avoid the problem of celluloid instability, the industry experimented with various other synthetic materials for billiard balls such as [[Bakelite]], [[Poly(methyl methacrylate)|Crystallite]] and other plastic compounds. The exacting requirements of the billiard ball are met today with balls cast from plastic materials that are strongly resistant to cracking and chipping. Currently [[Saluc]], under the brand names Aramith and Brunswick Centennial, manufactures [[phenolic resin]] balls.<ref>[http://www.saluc.com/html/billiard/index.php Aramith]</ref><ref>{{cite web|url=http://www.brunswickbilliards.com/our_rich_history/billiard_balls/index.html|title=History|work=brunswickbilliards.com|access-date=9 February 2016|archive-url=https://web.archive.org/web/20140327190020/http://www.brunswickbilliards.com/our_rich_history/billiard_balls/index.html|archive-date=27 March 2014|dead-url=yes|df=dmy-all}}</ref> Other plastics and resins such as [[polyester]] (under various trade names) and clear [[Acrylic glass|acrylic]] are also used. Ivory balls remained in use in [[artistic billiards]] competition until the late 20th century.<ref name="Shamos 1999" />{{rp|17}} ==Types== ===Carom billiards=== [[File:Carom billiards balls.jpg|thumb|200px|Carom balls, [[Four-ball billiards|four-ball]] needs an additional object ball.]] In the realm of [[carom billiards]] (or carambole) games, three balls are used to play [[straight-rail]], [[three-cushion]], [[balkline and straight rail|balkline]], [[Five-pin billiards|five-pins]], and related games on pocketless [[billiards table]]s. The exception is [[Four-ball billiards|four-ball]] which needs an extra object ball. Carom balls are not numbered, and at 61–61.5&nbsp;mm (between approximately {{frac|2|3|8}} and {{frac|2|7|16}}&nbsp;in) in diameter<ref name="UMB-II-12-2">{{cite web |url=http://www.umb.org/Rules/Carom_Rules.pdf |format=PDF |title=World Rules of {{sic|hide=y|Carom Billiard|reason=Yes, UMB did leave off the "s" in "Billiards".}} |at=Chapter II ("Equipment"), Article 12 ("Balls, Chalk"), Section 2 |work=UMB.org |author= |publisher=[[Union Mondiale de Billard]] |location=Sint-Martens-Latem, Belgium |date=1 January 1989 |archiveurl=https://web.archive.org/web/20070928031638/http://www.umb.org/Rules/Carom_Rules.pdf |archivedate=28 September 2007 |accessdate=5 March 2007 |deadurl=yes |df=dmy }} Officially but somewhat poorly translated version, from the French original.</ref> are larger than pool balls. The 61.5&nbsp;mm size are more common. They are typically colored as follows: :* Red {{Cuegloss|Object ball|object ball}} (or, uncommonly, blue; two object balls are used in [[Four-ball billiards|four-ball]]) :* White {{Cuegloss|Cue ball|cue ball}} for player 1 :* White with a spot (or sometimes yellow) cue ball for player 2 ===Pool=== {{anchor|American-style pool}} {|class="wikitable" style="font-size:90%;float:left; margin:1em 2em 1em 0em;" |- |align=center|1||bgcolor="gold" colspan=3| ||yellow |- |align=center|2||bgcolor="blue" colspan=3| ||blue |- |align=center|3||bgcolor="red" colspan=3| ||red |- |align=center|4||bgcolor="indigo" colspan=3| ||violet |- |align=center|5||bgcolor="orangered" colspan=3| ||orange |- |align=center|6||bgcolor="forestgreen" colspan=3| ||green |- |align=center|7||bgcolor="brown" colspan=3| ||brown |- |align=center|8||bgcolor="black" colspan=3| ||black |- |align=center|9||bgcolor="white"| ||bgcolor="gold"| ||bgcolor="white"| ||yellow and white |- |align=center|10||bgcolor="white"| ||bgcolor="blue"| ||bgcolor="white"| ||blue and white |- |align=center|11||bgcolor="white"| ||bgcolor="red"| ||bgcolor="white"| ||red and white |- |align=center|12||bgcolor="white"| ||bgcolor="indigo"| ||bgcolor="white"| ||violet and white |- |align=center|13||bgcolor="white"| ||bgcolor="orangered"| ||bgcolor="white"| ||orange and white |- |align=center|14||bgcolor="white"| ||bgcolor="forestgreen"| ||bgcolor="white"| ||green and white |- |align=center|15||bgcolor="white"| ||bgcolor="brown"| ||bgcolor="white"| ||brown and white |- |align=center|•||bgcolor="white" colspan=3| ||{{Cuegloss|Cue ball|cue ball}}, white or off-white <small>(sometimes with one or more spots)</small> |} {{Multiple image |total_width=400 |image1=Bicentennial Billard Balls.jpg |caption1=Old style [[Brunswick Corporation|Brunswick]] pool balls, the numbers are not located on the stripe |image2=Cribbage pool rack closeup.jpg |caption2=Modern style [[Saluc|Super Aramith Pro]] pool balls racked in [[Cribbage (pool)|Cribbage]] arrangement }} Pool balls are used to play various [[Pool (cue sports)|pool]] (pocket billiards or pool billiards) games, such as [[eight-ball]], [[nine-ball]] and [[one-pocket]]. In North America and Asia, they are referred to simply as "billiard balls" (except among carom and snooker players). These balls, used the most widely throughout the world, are considerably smaller than carom billiards balls, slightly larger than British-style pool balls and substantially larger than those for snooker. According to [[World Pool-Billiard Association|WPA]]/[[Billiard Congress of America|BCA]] equipment specifications, the weight may be from {{cvt|5.5|to(-)|6.0|oz|g}} with a diameter of {{cvt|2.250|in|mm}}, plus or minus {{cvt|0.005|in|mm|3}}.<ref name="WPAequipspec">{{cite web |url=http://www.wpa-pool.com/web/WPA_Tournament_Table_Equipment_Specifications |archiveurl=https://web.archive.org/web/20130928165510/http://www.wpa-pool.com/web/WPA_Tournament_Table_Equipment_Specifications |archivedate=2013-09-28 |title=WPA Tournament Table & Equipment Specifications |work=WPA-Pool.com |publisher=World Pool-Billiard Association |date=November 2001 }}</ref><ref name="BCAbook">{{cite book | year = 2004 | title = Billiards: The Official Rules and Records Book | publisher = [[Billiards Congress of America]] | location = [[Colorado Springs, Colorado|Colorado Springs]] | page = 5 | isbn = 978-1-878493-14-9 | author = BCA Rules Committee }}</ref> These are often referred to as {{convert|2+1/4|in|mm|adj=on}} balls. The balls are numbered and colored as in the table. The first series of the numbering of the balls from 1 through 7 being solid. Are the same as 9 to 15 being striped. They are eight away from the other of the same color. [[File:Baseball pool balls and rack.png|thumb|Extended set for [[baseball pocket billiards]].]] In [[baseball pocket billiards]], the ball set is extended to 21 balls, in which the 16 ball is black and white, while balls 17 through 21 have no special design, but look exactly like balls 9 through 13, respectively, except for their numbers. Balls 1 through 7 are often referred to as {{Cuegloss|Solids|solids}} and 9 through 15 as {{Cuegloss|Stripes|stripes}} though there are many other colloquial terms for each {{Cuegloss|Suit|suit}} of balls (highs and lows, etc.). Striped balls were introduced around 1889.<ref name="Shamos 1999" />{{rp|246}} Though it looks similar to the solids, the 8 ball is not considered a solid because it is the only ball that is black. Some games such as nine-ball do not distinguish between stripes and solids, but rather use the numbering on the balls to determine which {{Cuegloss|Object ball|object ball}} must be pocketed. In other games such as [[three-ball]] and [[straight pool]] neither type of marking is of any consequence. In eight-ball, straight pool, and related games, all sixteen balls are employed. In the games of [[seven-ball]], nine-ball, [[ten-ball]] and related, only object balls 1 through 7, 9 and 10, respectively (plus the cue ball) are used. Some balls used in televised pool games are colored differently in order to make them distinguishable on television monitors. Specifically, the 4 ball is colored pink instead of dark violet, and the 12 is white with a pink stripe, to make it easier to distinguish their color from the black 8 ball, and similarly the 7 and 15 balls use a light tan color instead of a deep maroon. Television was also the genesis of the cue ball with six red spots on its surface (known as a "measles" cue ball) so that {{Cuegloss|Spin|spin}} placed on it is evident to viewers. Red also signifies non magnetic. Where as green is signifying magnetic, also sometimes blue! For Coin-operated tables as mentioned in the next paragraph. Coin-operated pool tables such as those found at [[Bar (establishment)|bars]] historically have often used either an oversized cue, larger than the more popular magnetic cue. Sometimes the cue can be a less expensive type of ball refereed to as a mud ball. Which is a ball with metal grindings mixed into the resin, so much it is magnetic enough to separate, like a metal core ball! Unlike the regular set of balls (which are captured until the game ends and the table is paid again for another game) as it makes it possible that the cue ball can be returned for further play, should it be accidentally potted.) Oversized, I have seen, but not used in my area much. Where a regular coin op cue ball has a metal core in it. The oversize ball is separated by its size. A magnetic ball is separated by a magnet! In Asia and Europe, some pool tables use a smaller cue ball instead. Modern tables usually employ a magnetic ball of regulation or near-regulation size and weight, since players have complained for many decades that the heavy and often oversized cue balls do not "play" correctly. Addressing the oversize cue. When making any shot with an oversized cue 2-3/8". Will not be equal to the same shot with a regular cue or 2-1/4" size ball. When dealing with regular pool or pocket billiards. All the object balls are 2-1/4". If you hit any one of them with an oversize cue you will not be able to hit the object ball square for any shot as it is higher, and not center on a rail shot. Center to center it is 1/16 off! This is a good argument for using a magnetic cue rather that oversize, on a coin op table!<!--R. Givens's "Eight-ball Bible" can be cited on these points, but my copy is missing. -SMcCandlish--> ===British-style pool (blackball)=== [[File:British Style Pool Balls.jpg|left|thumb|145px|Setup for blackball]] In WPA [[Blackball (pool)|blackball]] and its predecessor [[World Eight-ball Pool Federation|WEPF]] or ''English eight-ball pool'' (not to be confused with the games of eight-ball or English billiards), fifteen object balls again are used, but fall into two unnumbered {{Cuegloss|Group|groups}}, the {{Cuegloss|Red ball|reds}} (or less commonly {{Cuegloss|Blue ball|blues}}) and {{Cuegloss|Yellow ball|yellows}}, with a white cue ball, and black 8 ball. Aside from the 8, shots are not {{Cuegloss|Call-shot|called}} since there is no reliable way to identify particular balls to be pocketed. Because they are unnumbered they are wholly unsuited to certain pool games, such as nine-ball, in which ball order is important. They are noticeably smaller than the American-style balls, and with a cue ball that is slightly smaller than the object balls, while the table's {{Cuegloss|Pocket|pockets}} are tighter to compensate. Neither the WPA nor the WEPF (publicly) define ball or even table dimensions, though presumably{{cn|date=August 2017}} league and tournament organizers are given some guidelines in this regard. Most manufacturers that supply this market provide sets that range from {{convert|2|in|mm|0}} up to {{convert|2+3/16|in|mm|0}}, often with a slightly smaller cue ball, e.g. {{cvt|1+7/8|in|mm|0}} for a 2-inch set. The most common object ball diameters are {{cvt|2|in|mm|0}} and {{cvt|2+1/8|in|mm|0}}. The yellow-and-red sets are sometimes commercially referred to as "casino sets" (they were formerly used for televised eight-ball championships,<ref name="Shamos 1999"/>{{rp|45}} most often held in casinos). The use of such sets, however, predates television, as they were used for B.B.C. Co. Pool, the forerunner of modern eight-ball, at least as early as 1908.<ref name="Shamos 1999" />{{rp|24}} ===Snooker=== [[File:Set of Snookerballs.png|thumb|right|300px|Complete set of snooker balls.]] {| class="wikitable" style="font-size:90%;float:left; margin:1em 2em 1em 0em;" |- !Colour!!Value |- | [[File:Snooker_ball_red.png|14px]] {{Cuegloss|Red ball|Red}}|| 1 point |- | [[File:Snooker_ball_yellow.png|14px]] {{Cuegloss|Yellow ball|Yellow}} || 2 points |- | [[File:Snooker_ball_green.png|14px]] {{Cuegloss|Green ball|Green}} || 3 points |- | [[File:Snooker_ball_brown.png|14px]] {{Cuegloss|Brown ball|Brown}} || 4 points |- | [[File:Snooker_ball_blue.png|14px]] {{Cuegloss|Blue ball|Blue}} || 5 points |- | [[File:Snooker_ball_pink.png|14px]] {{Cuegloss|Pink ball|Pink}} || 6 points |- | [[File:Snooker_ball_black.png|14px]] {{Cuegloss|Black ball|Black}} || 7 points |} Ball sets for the sport of snooker look at first glance like a mixture of American- and British-style pool balls. There are twenty-two balls in total, arranged as a rack of 15 unmarked reds, six {{Cuegloss|Colour ball|colour balls}} placed at various predetermined spots on the table, and a white cue ball. ''(See [[snooker]] for more information on ball setup.)'' The colour balls are sometimes numbered American-style, with their point values, for the amateur/home market, as follows in the adjacent table. Snooker balls are technically standardized at {{cvt|52.5|mm|in|2}} in diameter within a tolerance of plus or minus {{cvt|0.05|mm|in|3}}. No standard weight is defined, but all balls in the set must be the same weight within a tolerance of {{cvt|3|g|oz|2}}.<ref name="WSAequipspec">[http://www.worldsnooker.com/equipment.htm "Equipment"] {{webarchive|url=https://web.archive.org/web/20080801105033/http://www.worldsnooker.com/equipment.htm |date=1 August 2008 }}, World Snooker Association, publication date unknown (Retrieved 28 January 2007), London, UK.</ref> However, many sets are actually {{cvt|2+1/16|in|mm|1}}, even from major manufacturers. Snooker sets are also available with considerably smaller-than-regulation balls (and even with ten instead of fifteen reds) for play on smaller tables (down to half-size), and are sanctioned for use in some amateur leagues. Sets for [[Snooker|American snooker]] are typically {{cvt|2+1/8|in|mm|1}}, with numbered colour balls. {{clear left}} The set of eight colours used for snooker balls (including white) are thought to be derived from the game of [[croquet]]. Snooker was invented in 1884 by [[Neville Francis Fitzgerald Chamberlain|British Army officers]] stationed in India. Croquet reached its peak popularity at the same time, particularly amongst people in the same social context. The eight coloured balls of croquet use the same identical set of eight colours. There are many other similarities between croquet and snooker, which when taken together, suggest that the derivation of the latter owes much to the existence of the former.<ref>{{cite web|title=An Introduction to Croquet: A Brief History|url=https://www.croquet.org.uk/?p=tech/CroquetIntro#history|publisher=The Croquet Association (of England and Wales)|accessdate=13 May 2017}}</ref> ===Other games=== {{Multiple image |total_width=400 |image1=Russian billiards ball at a corner pocket.jpg |caption1=Russian pyramid ball at a corner pocket. The relative size of the ball and the pocket makes the game very challenging. |image2=Golfbiljart Doel.jpg |caption2=Bumper pool ball near a pocket. The bumpers increase the difficulty in potting the ball. }} Various other games have their own variants of billiard balls. [[English billiards]] balls are like carom balls but are the same size as snooker balls. [[Russian pyramid]] uses a set of fifteen numbered but otherwise all-white balls, and a red or yellow cue ball that may be even larger than carom billiards balls at 68&nbsp;mm (2¹¹⁄₁₆&nbsp;in) or 72&nbsp;mm (2⁴⁄₅ in). [[Kaisa (cue sport)|Kaisa]] has the same pocket and ball dimensions but uses only five balls: one yellow, two red and two cue balls, one for each player.<ref name="BVRP">{{Cite web |url=https://cuesup.com/russian-pyramid-pool-a-game-bearing-more-games/ |title=Russian Billiards|work=CuesUp.com |author=<!--Staff writer; no byline.--> |year=2016 |accessdate=2016-12-28 }}</ref> [[Bumper pool]] requires four white and four red object balls, and two special balls, one red with a white spot and the other white with red spot; all are usually {{frac|2|1|8}} inch (approximately 52.5&nbsp;mm) in diameter. [[Bar billiards]] uses six or seven white balls (depending on regional variations) and one red ball {{cvt|1+7/8|in|mm|0}} in diameter. ===Training balls=== [[File:Jim Rempe practice ball.jpg|thumb|150px|left|The [[Jim Rempe]] Training Ball]] Several brands of practice balls exist, which have systems of spots, stripes, differently colored halves and/or targeting rings. For example, Saluc markets several practice ball systems, including the Jim Rempe Training Ball, a {{Cuegloss|Cue ball|cue ball}} marked with rings and targets on the surface of the ball so that the practicing player can better judge the effects of very particular amounts of {{Cuegloss|Sidespin|sidespin}}, {{Cuegloss|Topspin|topspin}}, {{Cuegloss|Backspin|backspin}} and other forms of cue ball control, and learn better control of [[Cue stick|cue]] {{Cuegloss|Stroke|stroke}}.<ref name="Saluc 1">{{Cite web|url= http://www.saluc.com/html/index.php?idlien=17 |title=Product Line &gt; Training Balls|year=2005|work=Saluc.com|publisher=[[Saluc|Saluc S.A.]]|location=Callenelle, Belgium|accessdate=2008-02-18}} {{Dead link|date=October 2010|bot=H3llBot}}</ref> Various competing products, such as several other Saluc models<ref name="Saluc 1" /> and Elephant Practice Balls,<ref name="Elephant">{{Cite web|url= http://www.elephantballs.com/store/products/22 |title=Elephant Practice Balls|year=2007|work=ElephantBalls.com|publisher=Elephant Balls, Ltd.|location=Columbus, Ohio|accessdate=2008-02-18}}</ref> use a similar aiming system. Some such sets consist of just a special cue ball and manual, while others also include an object ball marked for aiming practice. {{clear}} ===Novelty balls=== [[File:Novelty billiard balls.jpg|thumb|right|200px|Various novelty [[pocket billiards]] balls. Clockwise from the top: Red and white balls and markers from a proprietary game called Starball; an [[Elvis Presley]] commemorative cue ball from [[Graceland]]; a [[leopard]]-patterned 9 ball; colorful balls from a [[poker]]-themed set; regular balls and the small "jack" from a miniature [[bocce]] set used on a table instead of a lawn or court.]] There is a market for specialty cue balls and even entire ball sets, featuring sports team logos, cartoon characters, animal pelt patterns, etc. Entrepreneurial inventors also supply a variety of novelty billiard games with unique rules and balls, some with playing card markings, others with stars and stripes, and yet others in sets of more than thirty balls in several suits. Marbled-looking and glittery materials are also popular for home tables. There are even [[blacklight]] sets for playing in near-dark. There are also [[practical joke]] cue and 8 balls, with off-center weights in them that make their paths curve and wobble. Miniature sets in various sizes (typically {{frac||2|3}} or {{frac||1|2}} of normal size) are also commonly available, primarily intended for undersized toy tables. Even an egg-shaped ball has been patented<ref>U.S. Patent No. 7,468,002</ref> and marketed under such names as Bobble Ball and Tag Ball. ==In popular culture== [[File:8 ball face.jpg|thumb|left|A [[Magic 8 Ball]]]] [[File:USS Sam Rayburn (SSBN-635) missile hatches.jpg|thumb|upright|[[Ballistic missile submarine]] {{USS|Sam Rayburn|SSBN-635|6}} displays a billiard motif on her missile hatches]] The 8 ball is frequently used iconically in Western, especially American, culture. It can often be found as an element of T-shirt designs, album covers and names, tattoos, household goods like paperweights and cigarette lighters, belt buckles, etc. A classic toy is the [[Magic 8-Ball]] "oracle". [[Don and Ron Harris|A wrestler]], [[Eightball & MJG|a rapper]], and [[8-Ball (band)|a rock band]] have all independently adopted the name. The term "8-ball" is also [[slang]] both for {{convert|1/8|oz|g}} of [[cocaine]] or [[crystal methamphetamine|crystal meth]], and for a bottle of [[Olde English 800]] [[malt liquor]]. It has also been used to refer to African-Americans, particularly those of darker skin tones, as in the film ''[[Full Metal Jacket]]''. The expression "behind the eight [ball]" is used to indicate a [[dilemma]] from which it is difficult to extricate oneself. The term derives from the game [[kelly pool]].<ref name="IEOB">{{cite book | last = Shamos | first = Michael Ian | year = 1993 | title = The Illustrated Encyclopedia of Billiards | publisher = Lyons & Burford | location = New York City | pages = 85, 128 and 168 | isbn = 1-55821-219-1}}</ref><ref>{{cite journal | last = Jewett | first = Bob |date=February 2002 | title = 8-Ball Rules: The many different versions of one of today's most common games | journal = Billiards Digest Magazine | pages = Pages 22–23}}</ref><ref>Ralph Hickok (2001). [http://www.hickoksports.com/history/billiard.shtml Sports History: Pocket Billiards] {{webarchive|url=http://webarchive.loc.gov/all/20020223060649/http://www.hickoksports.com/history/billiard.shtml |date=23 February 2002 }}. Retrieved 22 February 2007.</ref><ref>Billiard Congress America (1995–2005) [http://www.bca-pool.com/aboutus/history/start.shtml A Brief History of the Noble Game of Billiards] {{webarchive|url=https://web.archive.org/web/20070127151057/http://www.bca-pool.com/aboutus/history/start.shtml |date=27 January 2007 }} by Mike Shamos. Retrieved 22 February 2007.</ref><ref name="Mizerak">{{cite book | author= Steve Mizerak and Michael E. Panozzo | title = Steve Mizerak's Complete Book of Pool | publisher = Contemporary Books | location = [[Chicago|Chicago, Ill]] | pages = 127–8 | year = 1990 | isbn = 0-8092-4255-9}}</ref> In the ''[[Seinfeld]]'' episode "[[The Reverse Peephole]]", the character Puddy wears a jacket featuring the eight-ball. Because the [[Collision#Billiards|collisions between billiard balls]] are nearly [[Elastic collision|elastic]], and the balls roll on a surface that produces low [[rolling friction]], their behavior is often used to illustrate [[Newton's laws of motion]]. Idealized, frictionless billiard balls are a staple of [[Mathematics|mathematical]] theorems and [[physics]] models, and figure in [[dynamical billiards]], [[scattering theory]], [[Lissajous knots]], [[billiard ball computing]] and [[Reversible cellular automaton|reversible cellular automata]], [[Polchinski's paradox]], [[contact dynamics]], [[collision detection]], the [[illumination problem]], [[Ultracold atom|atomic ultracooling]], [[quantum mirage]]s and elsewhere in these fields. "Billiard balls" or "pool balls" is the name given to balls used in [[stage magic]] tricks, especially the classic "[[multiplying billiard balls]]". Though obviously derived from real billiard balls, today they are usually smaller, for easier manipulation and hiding, but not so small and light that they are difficult to [[juggle]], as the magic and juggling disciplines have often overlapped since their successful combination by pioneers like [[Paul Vandy]]. An urban legend received cultural attention to many saying, "If the [[Earth]] were the size of a billiard ball, it would be smoother". It was used in 2008's Discover Magazine<ref>{{cite web |url=http://blogs.discovermagazine.com/badastronomy/2008/09/08/ten-things-you-dont-know-about-the-earth/#.VpDO6I-cGCg |title=Ten things you don't know about the Earth |publisher=Bad Astronomy |date=8 September 2008 |accessdate=8 September 2008}}</ref> stating no diameter variations measuring +/-0.005" should be made, but mistook the diameter tolerance for smoothness. If the Earth were reduced to the size of a billiard ball, its mountains and trenches would equal the texture of 320 grit sandpaper and the variation in diameter would be 0.0049", which is near the maximum diameter tolerance.<ref>{{cite web |url=https://ourplnt.com/earth-smooth-billiard-ball/ |title=IS EARTH AS SMOOTH AS A BILLIARD BALL? NO, HERE’S WHY |publisher=Our Planet |date=17 August 2017 |accessdate=17 August 2017}}</ref> (see also: [[Earth#Shape|Earth's Shape]]) The phrase "as smooth as a billiard ball" is sometimes applied to describe a [[Baldness|bald person]], and the term "cue ball" is also slang for someone who sports a [[shaved head]]. In [[Polandball]], numbered pool balls are used to denote aboriginal, prehistoric, or native peoples who do not have a flag of their own. Green 6-balls also denote [[extraterrestrial intelligence|extraterrestrials]]. {{clear}} ==References== {{reflist}} ===Patents=== * {{US patent|50359}}—Billiard ball {{circa|1865}} * {{US patent|76765}}—Billiard ball {{circa|1868}} * {{US patent|88634}}—Billiard ball {{circa|1869}} * {{US patent|114945}}—Billiard ball {{circa|1871}} {{Cue sports nav}} {{DEFAULTSORT:Billiard Ball}} [[Category:Cue sports equipment|Ball, billiard]] [[Category:Balls]] [[Category:Game equipment]]'