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Cheers

Cheers is an American television sitcom that aired on NBC from September 30, 1982 to May 20, 1993 for 11 seasons and 275 episodes. The show was produced by Charles/Burrows/Charles Productions in association with Paramount Network Television and was created by the team of James Burrows and Glen and Les Charles. The show is set in the titular bar in Boston, where a group of locals meet to drink, relax, socialize, and escape from their day to day issues.

At the center of the show is the bar's owner and head bartender, Sam Malone, who is a womanizing former relief pitcher for the Boston Red Sox. The show's ensemble cast introduced in the pilot episode are waitresses Diane Chambers and Carla Tortelli, second bartender Coach Ernie Pantusso, and regular customers Norm Peterson and Cliff Clavin. Later main characters of the show also include Frasier Crane, Woody Boyd, Lilith Sternin, and Rebecca Howe.

After premiering in 1982, it was nearly canceled during its first season when it ranked almost last in ratings for its premiere (74th out of 77 shows). However, Cheers eventually became a Nielsen ratings juggernaut in the United States, earning a top-10 rating during eight of its 11 seasons, including one season at number one (season 9). The show spent most of its run on NBC's Thursday night "Must See TV" lineup. Its widely watched series finale in 1993 became the most-watched single TV episode of the 1990s, and the show's 275 episodes have been successfully syndicated worldwide. Nominated for Outstanding Comedy Series for all 11 of its seasons on the air, it earned 28 Primetime Emmy Awards from a record of 117 nominations.

During its run, Cheers became one of the most popular series in history and received critical acclaim from its start to its end. In 1997, the episodes "Thanksgiving Orphans" and "Home Is the Sailor," aired originally in 1987, were respectively ranked No. 7 and No. 45 on TV Guide's 100 Greatest Episodes of All Time. Its series finale was watched by an estimated 93 million viewers, almost 40% of the US population at the time. The series also produced three spin-offs: The Tortellis, Wings, and Frasier; and a Spanish remake. In 2002, Cheers was ranked No. 18 on TV Guide's 50 Greatest TV Shows of All Time. In 2013, the Writers Guild of America ranked it as the eighth-best-written TV series and TV Guide ranked it No. 11 on their list of the 60 greatest shows.

Characters
Before the Cheers pilot "Give Me a Ring Sometime" was completed and aired in 1982, the series consisted of four employees in the first script. Later revisions added Norm Peterson and Cliff Clavin (regular customers of Cheers) as among the regular characters of the series, even though neither were featured.

In later years, Woody Boyd replaced Coach, after the character died off-screen in season three (1984–85), following actor Nicholas Colasanto's death. Frasier Crane started as a recurring character and became a permanent one. In season six (1987–88), new character Rebecca Howe was added, having been written into the show after the finale of the previous season (1986–87). Lilith Sternin started as a one-time character in an episode of season four, "Second Time Around" (1985). After her second season five appearance, she became a recurring character and was later featured as a permanent one during season 10 (1991–92).

Original main characters

 * Ted Danson as Sam Malone: A bartender and proprietor of Cheers, Sam is also a lothario. Before the series began, he was a baseball relief pitcher for the Boston Red Sox nicknamed "Mayday Malone" until he became an alcoholic, harming his career. He has an on-again, off-again relationship with Diane Chambers, his class opposite, in the first five seasons (1982–1987). During their off-times, Sam has flings with many not-so-bright "sexy women" yet fails to pursue a meaningful relationship. After Diane is written out of the series, he tries to pursue Rebecca Howe, with varying results. At the end of the series, he is still unmarried and faces his sexual addiction with the help of Dr. Robert Sutton's (Gilbert Lewis) group meetings, advised by Frasier.
 * Shelley Long as Diane Chambers: An academic, sophisticated graduate student attending Boston University. In the pilot, Diane is abandoned by her fiancé, leaving her without a job, a man or money. Realizing that one of her few practical skills is memorization, which comes in handy when dealing with drink orders, she reluctantly becomes a barmaid. Later, she becomes a close friend of Coach and has an on-and-off relationship with bartender Sam Malone, her class opposite. During their off-relationship times, Diane dates men who fit her upper-class ideals, such as Frasier Crane. Diane returns to Cheers while dating Frasier to help cure Sam of his drinking addiction with help from Dr. Crane. Diane's biggest enemy is Carla, who frequently insults her, but Diane's lack of retaliation serves to annoy Carla even more. In 1987, Diane leaves Boston and Sam for a writing and film or screenplay writing career in California. She promises Sam she will return to Boston to marry him but does not do so.
 * Nicholas Colasanto as "Coach" Ernie Pantusso: A "borderline senile" co-bartender, widower and retired baseball coach. Coach is also a friend of Sam and a close friend of Diane. He has a daughter, Lisa (Allyce Beasley). Coach listens to people's problems and solves them. However, other people also help resolve his own problems. In 1985, Coach died without explicit explanation, as Colasanto died of a heart attack.
 * Rhea Perlman as Carla Tortelli: A "wisecracking, cynical" cocktail waitress, who treats customers badly. When the series premieres, she is the mother of five children by her ex-husband Nick Tortelli (Dan Hedaya). Over the course of the series, she bears three more, the depiction of which incorporated Perlman's real-life pregnancies. All of her children are ill behaved, except Ludlow, whose father is a prominent academic. She flirts with men, including ones who are not flattered by her ways, and believes in superstitions. Later, she marries Eddie LeBec, an ice hockey player, who later becomes a penguin mascot for ice shows. After he dies in an ice show accident by an ice resurfacer, Carla later discovers that Eddie had committed bigamy with another woman, whom he had gotten pregnant. Carla sleeps with Sam's enemy, John Allen Hill, to Sam's annoyance and anger.
 * George Wendt as Norm Peterson: A bar regular and occasionally employed accountant. A recurrent joke on the show, especially in the earlier seasons, is that the character was such a popular and constant fixture at the bar that anytime he entered through the front door, everyone present would yell out his name ("NORM!") in greeting (when present in the scene Diane would be heard saying "Norman!" moments later) ; usually, this cry would be followed by one of the present bartenders asking Norm how he was, usually receiving a sardonic response and a request for a beer. ("It's a dog-eat-dog world, and I'm wearing Milkbone underwear.") He has infrequent accounting jobs and a troubled marriage with (but is still in love with and married to) Vera, an unseen character, though she is occasionally heard. Later in the series, he becomes a house painter and an interior decorator. Even later in the series, Norm secures his dream job, tasting beer at a brewery. The character was not originally intended to be a main cast role; Wendt auditioned for a minor role of George for the pilot episode. The role was only to be Diane Chambers' first customer and had only one word: "Beer!" After he was cast in a more permanent role, the character was renamed Norm.

Subsequent main characters
A know-it-all bar regular and mail carrier. He lives with his mother Esther Clavin (Frances Sternhagen) in first the family house and later his own apartment. In the bar, Cliff continuously spouts nonsensical and annoying trivia, making him an object of derision for the bar patrons (especially Carla). Ratzenberger auditioned for the role of a minor character George, but it went to Wendt, evolving the role into Norm Peterson. The producers decided they wanted a resident bar know-it-all, so the US Postal Worker Cliff Clavin was added for the pilot, as a recurring character for the first season before becoming a main character starting with the second. The producers changed his occupation into a mail carrier as they thought such a man would have wider knowledge than a guard. A psychiatrist and bar regular, a recurring character for seasons 3 and 4 who joins the main cast by season 5. Frasier started out as Diane Chambers' love interest in the third season (1984–85). In the fourth season (1985–86), after Diane jilts him at the altar in Europe, Frasier starts to frequent Cheers and becomes a regular. He later marries Lilith Sternin and has a son, Frederick. After the series ends, the character becomes the focus of the spin-off Frasier, in which he is divorced from Lilith and living in Seattle. A not-so-bright bartender, first appearing in season 4. He arrives from his Midwest hometown of Hanover, Indiana to Boston, to see Coach, his "pen pal" (as referring to exchanging "pens", not letters). When Sam tells Woody that Coach died, Sam hires Woody in Coach's place. Later, he marries his girlfriend Kelly Gaines (Jackie Swanson), also not-so-bright but raised in a rich family. In the final season, he runs for city council and, surprisingly, wins. A psychiatrist and bar regular, a recurring character until joining the main cast in season 10. She is often teased by bar patrons about her uptight personality and appearance. In "Second Time Around" (1986), her first and only episode of the fourth season, her date with Frasier does not go well because they constantly argue. In the fifth season, with help from Diane, Lilith and Frasier begin a relationship. Eventually, they marry and have a son, Frederick. In the eleventh and final season, she commits adultery and leaves Frasier to live with another man in an experimental underground environment called the "Eco-pod". She breaks it off, returns later in the season and reconciles with Frasier. However, in the spin-off Frasier, the couple has divorced, with Lilith maintaining custody of Frederick. In season 11 of Cheers, Bebe Neuwirth is given "starring" credit only when she appears. First appearing in season 6, she starts out as a strong independent woman, manager of the bar for the corporation that buys Cheers from Sam after his on-off relationship with Diane ends. Eventually, when Sam regains ownership, she begs him to let her remain, first as a cocktail waitress and later as a manager. She repeatedly has romantic failures with mainly rich men and becomes more and more "neurotic, insecure, and sexually frustrated". At the start, Sam frequently attempts to seduce Rebecca without success. As her personality changes, he loses interest in her. In the series finale, after failed relationships with rich men, Rebecca marries a plumber and quits working for the bar. In the Frasier episode "The Show Where Sam Shows Up", she is revealed to be divorced and back at the bar. When Frasier asks whether this means that she is working there again, Sam says, "No, she's just back at the bar."
 * John Ratzenberger as Cliff Clavin:
 * Kelsey Grammer as Frasier Crane:
 * Woody Harrelson as Woody Boyd:
 * Bebe Neuwirth as Lilith Sternin:
 * Kirstie Alley as Rebecca Howe:

Recurring characters
Although Cheers operated largely around that main ensemble cast and their interactions with various one-off characters, guest stars and recurring characters did occasionally supplement them. Notable repeat guests included Dan Hedaya as Nick Tortelli and Jean Kasem as Loretta Tortelli (who were the main characters in the first spin-off, The Tortellis), Fred Dryer as Dave Richards, Annie Golden as Margaret O'Keefe, Derek McGrath as Andy Schroeder (also referred to as Andy Andy), interchangeably Joel Polis and Robert Desiderio as rival bar owner Gary, Jay Thomas as Eddie LeBec, Roger Rees as Robin Colcord, Tom Skerritt as Evan Drake, Frances Sternhagen as Esther Clavin, Richard Doyle as Walter Gaines, Keene Curtis as John Allen Hill, Anthony Cistaro as Henri, Michael McGuire as Professor Sumner Sloan, and Harry Anderson as Harry "The Hat" Gittes. Jackie Swanson, who played the recurring role of Woody's girlfriend and eventual wife "Kelly Gaines-Boyd", appeared in 24 episodes from 1989 to 1993. The character is as equally dim and naive—but ultimately as sweet-natured—as Woody.

Paul Willson played the recurring barfly character Paul Krapence. (In one early appearance in the first season he was called "Glen", and was later credited on-screen as "Gregg" and "Tom", but he was playing the same character throughout.) Thomas Babson played "Tom", a law student often mocked by Cliff Clavin, for continually failing to pass the Massachusetts bar exam. "Al", played by Al Rosen, appeared in 38 episodes, and was known for his surly quips. Rhea Perlman's father Philip Perlman played the role of "Phil".

Celebrity appearances
Other celebrities guest-starred in single episodes as themselves throughout the series. Sports figures appeared on the show as themselves, with a connection to Boston or Sam's former team, the Red Sox, such as Luis Tiant, Wade Boggs, and Kevin McHale (of the Boston Celtics). Some television stars also made guest appearances as themselves such as Alex Trebek, Arsenio Hall, Dick Cavett, Robert Urich, George McFarland and Johnny Carson. Various political figures even made appearances on Cheers such as then-Chairman of the Joint Chiefs of Staff Admiral William J. Crowe, former Colorado Senator Gary Hart, then-Speaker of the House Tip O'Neill, then-Senator John Kerry, then-Governor Michael Dukakis, Ethel Kennedy (widow of Robert F. Kennedy), and then-Mayor of Boston Raymond Flynn, the last five of whom all represented Cheers' home state and city.

In maternal roles, Glynis Johns, in a guest appearance in 1983, played Diane's mother, Helen Chambers. Nancy Marchand played Frasier's mother, Hester Crane, in an episode that aired in 1985. In an episode that aired in 1992, Celeste Holm – who had previously played Ted Danson's mother in "Three Men and a Baby" – appeared as Kelly's jokester of a paternal grandmother. Melendy Britt appeared in the episode "Woody or Won't He" (1990) as Kelly's mother, Roxanne Gaines, a very attractive high-society lady and a sexy, flirtatious upper-class cougar who tries to seduce Woody.

The musician Harry Connick Jr. appeared in an episode as Woody's cousin and plays a song from his Grammy-winning album We Are in Love (c. 1991). John Cleese won a Primetime Emmy Award for his guest appearance as "Dr. Simon Finch-Royce" in the fifth-season episode "Simon Says". Emma Thompson guest-starred as Nanny G/Nannette Guzman, a famous singing nanny and Frasier's ex-wife. Christopher Lloyd guest-starred as a tortured artist who wanted to paint Diane. Marcia Cross portrayed Rebecca's sister Susan in the season 7 episode Sisterly Love. John Mahoney once appeared as an inept jingle writer, which included a brief conversation with Frasier Crane, whose father he later portrayed on the spin-off Frasier. Peri Gilpin, who later played Roz Doyle on Frasier, also appeared in one episode of Cheers, in its 11th season, as Holly Matheson, a reporter who interviews Woody. The Righteous Brothers, Bobby Hatfield and Bill Medley, also guest-starred in different episodes. In "The Guy Can't Help It", Rebecca meets a plumber, played by Tom Berenger, who came to fix one of the beer keg taps. They marry in the series finale, triggering her resignation from Cheers. Judith Barsi appears in the episode Relief Bartender.

Notable guest appearances of actresses portraying Sam's sexual conquests or potential sexual conquests include Kate Mulgrew in the three-episode finale of season four, portraying Boston councilwoman Janet Eldridge; Donna McKechnie as Debra, Sam's ex-wife (with whom he is on good terms), who pretends to be an intellectual in front of Diane; Barbara Babcock as Lana Marshall, a talent agent who specializes in representing male athletes, with whom she routinely sleeps on demand; Julia Duffy as Rebecca Prout, a depressed intellectual friend of Diane's; Alison La Placa as magazine reporter Paula Nelson; Carol Kane as Amanda, who Sam eventually learns was a fellow patient at the sanitarium with Diane; Barbara Feldon as Lauren Hudson, Sam's annual Valentine's Day fling (in an homage to Same Time, Next Year); Sandahl Bergman as Judy Marlowe, a longtime casual sex partner and whose now grown daughter, Laurie Marlowe (Chelsea Noble), who has always considered Sam a pseudo-father figure, Sam falls for; Madolyn Smith-Osborne as Dr. Sheila Rydell, a colleague of Frasier and Lilith; Valerie Mahaffey as Valerie Hill, John Allen Hill's daughter whom Sam pursues if only to gain an upper hand in his business relationship with Hill; and Alexis Smith as Alice Anne Volkman, Rebecca's much older ex-professor. In season 9, episode 17, "I'm Getting My Act Together and Sticking It in Your Face", Sam, believing Rebecca wants a more serious relationship, pretends to be gay, his lover being a casual friend named Leon (Jeff McCarthy)—the plan ultimately leads to a kiss between Sam and Leon.

Death of Nicholas Colasanto
Near the end of production of the third season, the writers of Cheers had to deal with the death of one of the main actors. Nicholas Colasanto's heart condition had been diagnosed in the mid-1970s, but it had worsened. He had lost weight and was having trouble breathing during filming, and he was hospitalized shortly before filming finished for season three due to fluid in his lungs. He recovered but was not cleared to return to work. He was visiting the set in January 1985 to watch the filming of several episodes, and co-star Shelley Long commented, "I think we were all in denial. We were all glad he was there, but he lost a lot of weight." Co-star Rhea Perlman added that he "wanted to be there so badly. He didn't want to be sick. He couldn't breathe well. It was hard. He was laboring all the time." Colasanto ultimately died of a heart attack at his home on February 12, 1985.

The third-season episodes of Cheers were filmed out of order, partly to accommodate Shelley Long's pregnancy. As a result, they had already completed filming the season finale at the time of his death, which had scenes with Colasanto in it. As the remaining episodes were filmed, Coach's absence was explained by having one of the characters mention that Coach was out of town for various reasons.

The Cheers writing staff assembled in June 1985 to discuss how to deal with the absence of Coach. They quickly discarded the idea that he had moved away, as they felt that he would never abandon his friends. In addition, most viewers were aware of Colasanto's death, so the writing staff decided to handle the situation more openly. The season four opener, "Birth, Death, Love and Rice", dealt with Coach's death and introduced Woody Harrelson, Colasanto's replacement.

Themes
Nearly all of Cheers takes place in the front room of the bar, but the characters often go into the rear pool room or the bar's office. Cheers does not show any action outside the bar until the first episode of the second season, which takes place in Diane's apartment.

The show's main theme in its early seasons is the romance between intellectual waitress Diane Chambers and the bar's owner, Sam Malone, a former Major League Baseball pitcher for the Boston Red Sox and recovering alcoholic. After Shelley Long (Diane) left the show, the focus shifted to Sam's new relationship with Rebecca Howe, a neurotic corporate ladder climber.

Many Cheers scripts centered or touched upon a variety of social issues, albeit humorously. As Toasting Cheers puts it, "The script was further strengthened by the writers' boldness in successfully tackling controversial issues such as alcoholism, homosexuality, and adultery."

Social class was a subtext of the show. The "upper class" — represented by characters like Diane Chambers, Frasier Crane, and Lilith Sternin — rub shoulders with middle- and working-class characters Sam Malone, Carla Tortelli, Norm Peterson, and Cliff Clavin. An extreme example of this was the relationship between Woody Boyd and a millionaire's daughter, Kelly Gaines. Many viewers enjoyed Cheers in part because of this focus on character development in addition to plot development.

Feminism and the role of women were also recurring themes throughout the show, with some critics seeing each of the major female characters portraying an aspect as a flawed feminist in her own way. Diane is a vocal feminist, and Sam is the epitome of everything she hates: promiscuity and chauvinism (see "Sam and Diane").

Homosexuality was dealt with from the first season, which was rare in the early 1980s on American television. In the first-season episode "The Boys in the Bar" (the title being a reference to the play and subsequent movie The Boys in the Band), a friend and former teammate of Sam's comes out in his autobiography. Some of the male regulars pressure Sam to take action to ensure that Cheers does not become a gay bar. The episode won a GLAAD Media Award, and the script's writers, Ken Levine and David Isaacs, were nominated for a Primetime Emmy Award.

Addiction also plays a role on Cheers, almost exclusively through Sam. He is a recovering alcoholic who had bought a bar during his drinking days. Frasier has a notable bout of drinking in the fourth-season episode "The Triangle", while Woody develops a gambling problem in the seventh season episode "Call Me Irresponsible". Carla and other characters drink beer while pregnant, but nobody seems to mind.

Cheers owners
Cheers had several owners before Sam, as the bar was opened in 1889. The "Est. 1895" on the bar's sign is a made-up date chosen by Carla for numerology purposes, revealed in season 8, episode 6, "The Stork Brings a Crane", which also revealed the bar's address as 112$1/2$ Beacon Street and that it originated under the name Mom's. In the series' second episode, "Sam's Women", Coach tells a customer looking for Gus, the owner of Cheers, that Gus is dead. In a later episode, Gus O'Mally comes back from Arizona for one night and helps run the bar.

The biggest storyline surrounding the ownership of Cheers begins in the fifth-season finale, "I Do, Adieu", when Sam and Diane part ways, due to Shelley Long's departure from the series. In addition, Sam leaves on a trip to circumnavigate the globe. Before he leaves, he sells Cheers to the Lillian Corporation. He returns in the sixth-season premiere, "Home is the Sailor", having sunk his boat, to find the bar under the new management of Rebecca Howe. He begs for his job back and is hired by Rebecca as a bartender. In the seventh-season premiere, "How to Recede in Business", Rebecca is fired and Sam is promoted to manager. Rebecca is allowed to keep a job at Lillian vaguely similar to what she had before, but only after Sam has Rebecca (in absentia) "agree" to a long list of demands that the corporation had for her.

From there, Sam occasionally attempts to buy the bar back with schemes that usually involve the wealthy executive Robin Colcord. Sam acquires Cheers again in the eighth-season finale, when it is sold back to him for 85¢ by the Lillian Corporation after he alerts the company to Colcord's insider trading. Fired by the corporation because of her silence on the issue, Rebecca is hired by Sam as a hostess/office manager. For the rest of the episode, to celebrate Sam's reclaiming the bar, a huge banner reading "Under OLD Management!" hangs from the staircase. When it is learned that the Pool Room and bathrooms are actually owned by Melville's (which spawns a war of wits between Sam and Melville's owner John Allen Hill), Rebecca later purchases them from Hill, making Sam and Rebecca partners in the ownership of Cheers (and more or less co-runners of the establishment).

Sam has two main battles. One is with Gary's Olde Towne Tavern, trying to beat them at some activity or another but always failing, except for one episode when Diane helps Cheers win the bowling trophy, and extending to the practical jokes they play on each other. The second is with Melville's owner John Allen Hill, who keeps annoying Sam with his pettiness and ego. Hill had an ongoing relationship with Carla.

Creation and concept
Some believe that the show is a rehashing of Boston's ABC affiliate WCVB's locally produced 1979 sitcom Park Street Under featuring Steve Sweeney and American Repertory Theater founder Karen MacDonald. Three men developed and created the Cheers television series: Glen and Les Charles ("Glen and Les") and James Burrows, who identified themselves as "two Mormons and a Jew." They aimed at "creating a show around a Spencer Tracy-Katharine Hepburn-type relationship" between their two main characters, Sam and Diane. Malone represents the average man, while Chambers represents class and sophistication. The show revolves around characters in a bar under "humorous adult themes" and "situations".

The original idea was a group of workers who interacted like a family, the goal being a concept similar to The Mary Tyler Moore Show. The creators considered making an American version of the British Fawlty Towers, set in a hotel or an inn. When the creators settled on a bar as their setting, the show began to resemble the radio program Duffy's Tavern, originally written and cocreated by James Burrows' father Abe Burrows. They liked the idea of a tavern, as it provided a continuous stream of new people, for a variety of characters. An early concept revolved around a woman becoming the new owner of the bar and the animosity created between her and the regulars, an idea that was used later in Season 6 when the character of Rebecca Howe is introduced.

Early discussions about the location of the show centered on Barstow, California, then Kansas City, Missouri. They eventually turned to the East Coast and finally Boston. The Bull & Finch Pub in Boston, which was the model for Cheers, was chosen from a phone book. When Glen Charles asked the bar's owner, Tom Kershaw, to shoot exterior and interior photos, he agreed, charging $1. Kershaw has since gone on to make millions of dollars, licensing the pub's image and selling a variety of Cheers memorabilia. The Bull & Finch became the 42nd-busiest outlet in the American food and beverage industry in 1997. During initial casting, Shelley Long, who was in Boston at the time filming A Small Circle of Friends, remarked that the bar in the script resembled a bar she had come upon in the city, which turned out to be the Bull & Finch.

Production team
The crew of Cheers numbered in the hundreds. The three creators—James Burrows and Glen and Les Charles—kept offices on Paramount's lot for the duration of the Cheers run. The Charles Brothers remained in overall charge throughout the show's run, frequently writing major episodes, though starting with the third season they began delegating the day-to-day running of the writing staff to various showrunners. Ken Estin and Sam Simon were appointed as showrunners for the third season, and succeeded by David Angell, Peter Casey and David Lee the following year. Angell, Casey and Lee would remain as showrunners until the end of the seventh season when they left to develop their own sitcom, Wings, and were replaced by Bill and Cheri Steinkellner and Phoef Sutton for the eighth through tenth seasons. For the final season, Tom Anderson and Dan O'Shannon acted as the showrunners.

James Burrows is regarded as being a factor in the show's longevity, directing 243 of the 270 episodes and supervising the show's production. Among the show's other directors were Andy Ackerman, Thomas Lofaro, Tim Berry, Tom Moore, Rick Beren, as well as cast members John Ratzenberger and George Wendt.

Craig Safan provided the series' original music for its entire run except the theme song. His extensive compositions for the show led to his winning numerous ASCAP Top TV Series awards for his music.

Casting
The character of Sam Malone was originally intended to be a retired football player and was slated to be played by Fred Dryer, but Danson was chosen in part because he was younger and had more acting experience than Dryer. After casting Ted Danson, it was decided that a former baseball player (Sam "Mayday" Malone) would be more believable than a retired football player. Dryer, however, went on to play sportscaster Dave Richards, an old friend of Sam, in three episodes. Bill Cosby was also considered early in the casting process for the role of Sam, after having been recommended by the network.

Shelley Long was recommended by various sources to the producers for the role of Diane Chambers, but Long wished to be offered the part straight out and had to be coaxed into giving an audition. When she did read for the part, according to Glen Charles, "that was it, we knew that we wanted her." Before the final decision was made, three pairs of actors were tested in front of the producers and network executives for Sam and Diane: Danson and Long, Fred Dryer and Julia Duffy, and William Devane and Lisa Eichhorn. The chemistry was so apparent between Long and Danson that it secured them the roles. Ted Danson was sent to bartending school to prepare him for the part and according to Burrows, had to learn "how to pretend that he knew a lot about sports" since Danson was not a sports fan in real life and had never been to a baseball game.

The character of Cliff Clavin was created for John Ratzenberger after he auditioned for the role of Norm Peterson, which eventually went to George Wendt. While chatting with producers afterward, he asked if they were going to include a "bar know-it-all", the part he eventually played. Alley joined the cast when Shelley Long left, and Woody Harrelson joined when Nicholas Colasanto died. Danson, Perlman and Wendt were the only actors to appear in every episode of the series; Ratzenberger appears in all but two (and his name wasn't part of the opening credit montage during the first season).

Filming styles and locations

Most Cheers episodes were, as a voiceover stated at the start of each, "filmed before a live studio audience" on Paramount Stage 25 in Hollywood, generally on Tuesday nights. Scripts for a new episode were issued the Wednesday before for a read-through, Friday was rehearsal day, and final scripts were issued on Monday. Burrows, who directed most episodes, insisted on using film stock rather than videotape. He was also noted for using motion in his directorial style, trying to constantly keep characters moving rather than standing still. Burrows and the Charles brothers emphasized to the cast to "never assume that you're not being watched" because the camera would be focused on the actors at all times, so they had to always be reacting and "always be funny". During the first season when ratings were poor Paramount and NBC asked that the show use videotape to save money, but a poor test taping ended the experiment and Cheers continued to use film.

Due to a decision by Glen and Les Charles, the cold open was often not connected to the rest of the episode, with the lowest-ranked writers assigned to create the jokes for them. Some cold opens were taken from episodes that ran too long.

The first year of the show took place entirely within the confines of the bar, the first location outside the bar being Diane's apartment in the second year. When the series became a hit, the characters started venturing further afield, first to other sets and eventually to an occasional exterior location. The exterior location shots of the bar are of the Bull & Finch Pub, located directly north of the Boston Public Garden. The pub has become a tourist attraction because of its association with the series, and draws nearly one million visitors annually. It has since been renamed Cheers Beacon Hill; its interior is different from the TV bar. The pub itself is at 84 Beacon Street (on the corner of Brimmer Street). In August 2001, there was a replica made of the bar in Faneuil Hall to capitalize on the popularity of the show.

After the show ended, the 1,000-square-foot bar set from Cheers was offered to the Smithsonian, which turned it down because it was too large. It was displayed for a short time at the defunct Hollywood Entertainment Museum, but later returned to storage, where it remained for many years. In 2014, CBS donated the set to the Museum of Television after a years-long campaign by James Burrows and his office on behalf of the museum's founder, James Comisar. At the time of the donation, Comisar initiated a planned $100,000 restoration of the set using former conservators from the Los Angeles County Museum of Art, although a site for the 10,000 item collection of the museum had not been decided upon.

Theme song
Before "Where Everybody Knows Your Name", written by Gary Portnoy and Judy Hart Angelo, became the show's theme song, Cheers' producers rejected two of Portnoy's and Hart Angelo's songs. The songwriters had collaborated to provide music for Preppies, an unsuccessful Broadway musical. When told they could not appropriate "People Like Us", Preppies' opening song, the pair wrote another song, "My Kind of People", which resembles "People Like Us" and was intended to satirize "the lifestyle of old decadent old-money WASPs", but to meet producers' demands, they rewrote the lyrics to be about "likeable losers" in a Boston bar. The show's producers rejected this song, as well. After they read the script of the series pilot, they created another song "Another Day". When Portnoy and Hart Angelo heard that NBC had commissioned thirteen episodes, they created an official theme song "Where Everybody Knows Your Name" and rewrote the lyrics. On syndicated airings of Cheers, the theme song was shortened to make room for additional commercials.

Critical reception
Cheers was critically acclaimed in its first season, though it landed a disappointing 74th out of 96 shows in that year's ratings. This critical support, the early success at the Primetime Emmy Awards, and the support of the president of NBC's entertainment division Brandon Tartikoff, are thought to be the main reasons for the show's survival and eventual success. Tartikoff stated in 1983 that Cheers was a sophisticated adult comedy and that NBC executives "never for a second doubted" that the show would be renewed. Writer Levine believes that the most important reason was that the network recognized that it did not have other hit shows to help promote Cheers; as he later wrote, "[NBC] had nothing else better to replace it with."

Writing in 2016, drama critic Chris Jones called Cheers "a hinge sitcom – one foot in classic bits and shtick not far removed from Mel Brooks and another in ambitious, Seinfeld-like absurdism." In 2013, GQ magazine held an online competition to find the best TV comedy. Cheers was voted the greatest comedy show of all time. In 2017, James Charisma of 'Paste' magazine ranked the show's opening sequence No. 5 on a list of The 75 Best TV Title Sequences of All Time. In 2022, Rolling Stone ranked Cheers as the eighth-greatest TV show of all time. In 2023, Variety ranked Cheers #11 on its list of the 100 greatest TV shows of all time.

Ratings
Ratings improved for the summer reruns after the first season. The cast went on various talk shows to try to further promote the series after its first season. By the second season Cheers was competitive with CBS's top-rated show Simon & Simon. With the growing popularity of Family Ties, which ran in the slot ahead of Cheers from January 1984 until Family Ties was moved to Sundays in 1987, and the placement of The Cosby Show in front of both at the start of their third season (1984), the line-up became a runaway ratings success that NBC eventually dubbed "Must See Thursday". The next season, Cheers ratings increased dramatically after Woody Boyd became a regular character as well. The fifth season earned the series the highest rating for the year that it would ever achieve. Although ratings mostly declined each year after that, the show retained a competitive advantage and rose to rank number one for the year for its first and only time in the ninth season. Although ratings and ranking both lost ground in the last two seasons, it still performed well, as it was the only show on NBC during those seasons to be in the top 10. By the end of its final season, the show had a run of eight consecutive seasons in the top ten of the Nielsen ratings; seven of them were in the top five.

NBC dedicated a whole night to the final episode of Cheers, following the one-hour season finale of Seinfeld (which was its lead-in). The show began with a "pregame" show hosted by Bob Costas, followed by the final 98-minute episode itself. NBC affiliates then aired tributes to Cheers during their local newscasts, and the night concluded with a special Tonight Show broadcast live from the Bull & Finch Pub. Although the episode fell short of its hyped ratings predictions to become the most-watched television episode, it was the most watched show that year, bringing in 93 million viewers (64 percent of all viewers that night), almost 40% of the US population at the time, and ranked 11th all time in entertainment programming. The 1993 final broadcast of Cheers also emerged as the highest rated broadcast of NBC to date, as well as the most watched single episode from any television series throughout the decade 1990s on U.S. television.

The episode originally aired in the usual Cheers spot of Thursday night, and was then rebroadcast on Sunday. While the original broadcast did not outperform the M*A*S*H finale, the combined non-repeating audiences for the Thursday and Sunday showings did. Television had greatly changed between the two finales, leaving Cheers with a broader array of competition for ratings.

NBC timeslots:
 * Season 1 Episodes 1–12: Thursday at 9:00 pm
 * Season 1 Episode 13 – Season 2 Episode 10: Thursday at 9:30 pm
 * Season 2 Episode 11 – Season 11 Episode 28: Thursday at 9:00 pm

Serialized storylines
Although not the first sitcom to do it, Cheers employed the use of end-of-season cliffhangers and, starting with the third season, the show's storylines became more serialized. The show's success helped make such multi-episode story arcs popular on sitcoms, which Les Charles regrets. "[W]e may have been partly responsible for what's going on now, where if you miss the first episode or two, you are lost. You have to wait until you can get the whole thing on DVD and catch up with it. If that blood is on our hands, I feel kind of badly about it. It can be very frustrating.'"

Cheers began with a limited five-character ensemble consisting of Ted Danson, Shelley Long, Rhea Perlman, Nicholas Colasanto and George Wendt. Cheers was able to gradually phase in characters such as Cliff, Frasier, Lilith, Rebecca, and Woody. By the time season 10 began, the show had eight front characters in its roster.

Awards and honors
Over its eleven-season run, the Cheers cast and crew earned many awards. The show garnered a record 111 Primetime Emmy Award nominations, with a total of 28 wins. In addition, Cheers earned 31 Golden Globe nominations, with a total of six wins. Danson, Long, Alley, Perlman, Wendt, Ratzenberger, Harrelson, Grammer, Neuwirth, and Colasanto all received Emmy nominations for their roles. Cheers won the Golden Globe Award for "Best TV-Series – Comedy/Musical" in 1991 and the Primetime Emmy Award for Outstanding Comedy Series in 1983, 1984, 1989, and 1991. The series was presented with the "Legend Award" at the 2006 TV Land Awards, with many of the surviving cast members attending the event.

The following are awards that have been earned by the Cheers cast and crew over its 11-season run:

Syndication
Cheers grew in popularity as it aired on American television and entered off-network syndication in 1987, initially distributed by Paramount Domestic Television. When the show went off the air in 1993, Cheers was syndicated in 38 countries, with 179 American television markets and 83 million viewers. When the quality of some earlier footage of Cheers began to deteriorate, it underwent a careful restoration in 2001. The series aired on Nick at Nite from 2001 to 2004 and on TV Land from 2004 to 2008, with Nick at Nite airing week-long Cheers "Everybody Knows Your Name" marathons. The show was removed from the lineup in 2004. The series began airing on Hallmark Channel in the United States in October 2008, and WGN America in 2009. In January 2011, Reelz Channel began airing the series in hour-long blocks. MeTV began airing Cheers weeknights in 2010. USA Network has aired the series on Sunday early mornings and weekday mornings to allow it to show extended-length films of $2 1/2$ hours and maintain symmetric schedules.

In 2011, Cheers was made available on the Netflix and Amazon Prime Video streaming services.

Cheers began airing on Eleven (a digital channel of Network Ten) in Australia on January 11, 2011. NCRV in the Netherlands aired all 275 episodes in sequence, once per night, repeating the series a total of three times.

In Italy, Cheers aired on Italia 1 & Canale 5 as Cin Cin from 1985 until 1988.

Cheers was first screened in the UK on Channel 4, and was one of the then-fledgling network's first imports. As of 2012, Cheers has been repeated on UK satellite channel CBS Drama. It has also been shown on the UK free-to-air channel ITV4, with two episodes every weeknight. On March 16, 2015, the series began airing on UK subscription channel Gold on weekdays at 9:30 a.m. and 10:00 a.m. Cheers aired again daily in 2019 on Channel 4.

High definition and 4K
A high-definition transfer of Cheers began running on HDNet in the United States in August 2010. The program was originally shot on film (but transferred to and edited on videotape) and broadcast in a 4:3 aspect ratio. The series has also been remastered for 4K

Home media
Paramount Home Entertainment and (from 2006 onward) CBS Home Entertainment have released all 11 seasons of Cheers on DVD in Region 1, Region 2, and Region 4. In the US, some episodes from the final three seasons appear on the DVDs with music substitutions. For example, in the episode "Grease", "I Fought the Law" was replaced even though its removal affects the comedic value of the scenes in which it was originally heard. The finale episode (73 minutes long without commercials) is presented in its three-part syndicated cut. The series is also available in high-definition Blu-ray.

On March 6, 2012, CBS released Fan Favorites: The Best of Cheers. Based on the 2012 Facebook poll, the selected episodes are:

 * 1) "Give Me a Ring Sometime" (season 1, episode 1)
 * 2) "Diane's Perfect Date" (season 1, episode 17)
 * 3) "Pick a Con, Any Con" (season 1, episode 19)
 * 4) "Abnormal Psychology" (season 5, episode 4)
 * 5) "Thanksgiving Orphans" (season 5, episode 9)
 * 6) "Dinner at Eight-ish" (season 5, episode 20)
 * 7) "Simon Says" (season 5, episode 21)
 * 8) "An Old-Fashioned Wedding", parts one and two (season 10, episodes 25)

On May 5, 2015, CBS DVD released Cheers – The Complete Series on DVD in Region 1.

Digital media distribution
The complete 11 seasons of Cheers are available through the iTunes Store, Amazon Prime Video, Peacock and Hulu in high definition. In Canada, all seasons are available on streaming service Crave.

The entire series was available in the UK on All 4.

Licensing
The series lent itself naturally to the development of Cheers bar-related merchandise, culminating in the development of a chain of Cheers themed pubs. Paramount's licensing group, led by Tom McGrath, developed the Cheers pub concept initially in partnership with Host Marriott, which placed Cheers themed pubs in over 15 airports around the world. Boston boasts the original Cheers bar, historically known to Boston insiders as the Bull and Finch; a Cheers restaurant in the Faneuil Hall marketplace; and Sam's Place, a spin-off sports bar concept also located in Faneuil Hall. In 1997, Europe's first officially licensed Cheers bar opened in London's Regent's Street W1. Like Cheers Faneuil Hall, Cheers London is a replica of the set. The gala opening was attended by James Burrows and cast members George Wendt and John Ratzenberger. The Cheers bar in London closed on December 31, 2008. The actual bar set had been on display at the Hollywood Entertainment Museum until the museum's closing in early 2006.

The theme song to the show was eventually licensed to a Canadian restaurant, Kelsey's Neighbourhood Bar & Grill.

CBS currently holds the rights to the Cheers franchise as a result of the 2005 Viacom split which saw Paramount transfer its entire television studio to CBS (both CBS and Viacom would reunite in 2019).

Spin-offs
Some of the actors and actresses from Cheers brought their characters onto other television shows, either in a guest appearance or on a new spin-off series. The most successful Cheers spin-off was Frasier, which featured Frasier Crane following his relocation back to Seattle, Washington. Sam, Diane, and Woody all individually appeared in Frasier episodes, with Lilith appearing as a guest on multiple episodes. In the season nine episode "Cheerful Goodbyes", Frasier returns to Boston and meets up with the Cheers gang, later attending Cliff's retirement party. Frasier was revived in 2023, moving back to Boston like Cheers.

Although Frasier was more successful, The Tortellis was the first series to spin off from Cheers, premiering in 1987. The show featured Carla's ex-husband Nick Tortelli and his wife Loretta, but was canceled after 13 episodes and drew protests for its stereotypical depictions of Italian Americans.

Crossovers
In addition to direct spin-offs, several Cheers characters had guest appearance crossovers with other shows, including Wings and St. Elsewhere (episode "Cheers"). Cheers has also been spoofed or referenced in other media, including The Simpsons (spoofing the title sequence and theme song in "Flaming Moe's"; actually visiting the place with vocal role reprises of the majority of the principal cast in "Fear of Flying"), Scrubs (episode "My Life in Four Cameras"), and the 2012 comedy film Ted.

The eighth-anniversary special of Late Night with David Letterman, airing in 1990, begins with a scene at Cheers in which the bar's TV gets stuck on NBC and all the bar patrons decide to go home instead of staying to watch David Letterman. The scene was re-used to open Letterman's final episode in 1993. A similar scene aired in the Super Bowl XVII Pregame Show on NBC, in which the characters briefly discuss the upcoming game.

In 2019, members of the Cheers cast, Rhea Perlman, George Wendt, John Ratzenberger and Kirstie Alley reprised their characters in an episode of The Goldbergs where they play customers of Geoff's short-lived food delivery business.

In the 2010 show Adventure Time, the show Cheers is referenced a few times, usually by Ice King/Simon because it was his favorite show back when he was a human living in the 20th century. This is explored in greater detail in the 2023 spin-off series Fionna and Cake, which is partially set within the mind of Simon. All televisions in that world simply play an animated rendition of Cheers reruns on every channel, and the characters sometimes sing the theme song in difficult moments. The season finale of the show is simply entitled "Cheers".

Cultural references
In Australia, Cheers is remembered for its role in the infamous cancellation of the 1992 Nine Network special Australia's Naughtiest Home Videos. Due to the then-owner of Nine Network Kerry Packer's objections to its content, Australia's Naughtiest Home Videos was pulled off the air during its first and only broadcast; viewers saw the network abruptly begin airing a rerun of Cheers midway through the special, either after a scheduled commercial break or a Nine Network bumper claiming a technical problem. Nine Network's affiliate in Perth didn't air the special at all and filled its timeslot with two episodes of Cheers. When the program was re-aired in its entirety in 2008, it abruptly cut away to the opening of Cheers midway through in a reenactment of the incident before resuming the second half that didn't get aired.

In the Cheers episode "Woody For Hire, Norman Meets the Apes" Woody shows and tells everyone how he was an extra on Boston based drama Spenser: For Hire. In the season 4 episode of Seinfeld titled "The Pitch", Jerry and George are presenting their idea for a sitcom to NBC executives. George is unhappy with their offer and feels that he deserves the same salary as Ted Danson which he claims was $800,000 per episode, being that Cheers is also an NBC show. Danson's reported salary was actually $250,000 per episode. At this point Cheers was in its 10th season and Ted Danson had won an Emmy and a Golden Globe the year before. In another Seinfeld episode, The Trip, George runs into George Wendt (portraying himself) while backstage on the set of The Tonight Show and annoys him by suggesting that the series change its setting from a bar to a rec room or community center.

In the seventh episode of the second season of How I Met Your Mother, a coffee shop barista mistakenly hears Barney's name as "Swarley" and writes it on his cup. This leads to a running gag in which everyone mercilessly refers to Barney as "Swarley" despite his protests, which culminates in everyone in McClaren's bar shouting "Swarley" when he enters and playing the Cheers theme song. The credits are then shown in the "Cheers" style. In the season seven episode, In Tailgate, Ted and Barney are outraged with the price to get into MacLaren's on New Year's Eve, so they offer for everyone to come upstairs. In the apartment, there is a puzzles sign that is designed to parody Cheers. Ted and Barney employ Kevin as their bartender, and they invent a theme song which also parodies the Cheers theme song.

In the 2004 video game Tony Hawk's Underground 2, "Jeers" is set in Boston, with the typeface referencing the Cheers logo. It is located down a set of stairs, and when near the front door, there is bar chatter coming from inside.

In the 2015 video game Fallout 4, which is set in Boston, there is a bar named Prost Bar near Boston Common that, when entered, is an almost exact replica of the bar featured on the series. It includes two dead bodies sitting at the end of the bar, with one of them wearing a mail carrier's uniform, a direct reference to regular barfly Cliff Clavin.

In the season 2 finale of the NBC sitcom The Good Place, Ted Danson's character Michael appears as a bartender while wearing a blue plaid button-down, in a clear homage to Danson's character in Cheers.

Remake
In September 2011, Plural Entertainment debuted a remake of the series on Spanish television, also titled Cheers. Set at an Irish pub, it starred Alberto San Juan as Nicolás "Nico" Arnedo, the equivalent of Sam Malone on the original series. It also used the original theme song, rerecorded in Spanish by Dani Martín, under the title "Donde la gente se divierte."

In December 2012, The Irish Film and Television Network announced that casting was underway on an Irish-language version of Cheers produced by production company Sideline. The new show, tentatively titled Teach Seán, would air on Ireland's TG4 and features a main character who, like Sam Malone, is a bar owner, a retired athlete, and a recovering alcoholic. However, because of being set in Ireland, the barman is a "former hurling star" rather than an ex-baseball player. As of August 2019, the Irish remake has not occurred.

Cheers: Live on Stage
On September 9, 2016, a stage adaptation called Cheers: Live on Stage opened at the Shubert Theatre in Boston. Comprising pieces of the original TV series, the play was adapted by Erik Forrest Jackson. It was produced by Troika/Stageworks. The director was Matt Lenz. It starred Grayson Powell as Sam Malone, Jillian Louis as Diane Chambers, Barry Pearl as Ernie "Coach" Pantusso, Sarah Sirotta as Carla Tortelli, Paul Vogt as Norm Peterson, and Buzz Roddy as Cliff Clavin. The production was scheduled to tour through 2017, but was cancelled in 2016.

title: Cheers


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Counterpoint

In music, counterpoint is a method of composition in which two or more musical lines (or voices) are simultaneously played which are harmonically correlated yet independent in rhythm and melodic contour. It has been most commonly identified in the European classical tradition, strongly developing during the Renaissance and in much of the common practice period, especially in the Baroque period. The term originates from the Latin punctus contra punctum meaning "point against point", i.e. "note against note".

In Western pedagogy, counterpoint is taught through a system of species (see below).

There are several different forms of counterpoint, including imitative counterpoint and free counterpoint. Imitative counterpoint involves the repetition of a main melodic idea across different vocal parts, with or without variation. Compositions written in free counterpoint often incorporate non-traditional harmonies and chords, chromaticism and dissonance.

General principles
The term "counterpoint" has been used to designate a voice or even an entire composition. Counterpoint focuses on melodic interaction—only secondarily on the harmonies produced by that interaction. In the words of John Rahn:

"It is hard to write a beautiful song. It is harder to write several individually beautiful songs that, when sung simultaneously, sound as a more beautiful polyphonic whole. The internal structures that create each of the voices separately must contribute to the emergent structure of the polyphony, which in turn must reinforce and comment on the structures of the individual voices. The way that is accomplished in detail is ... 'counterpoint'."

Work initiated by Guerino Mazzola (born 1947) has given counterpoint theory a mathematical foundation. In particular, Mazzola's model gives a structural (and not psychological) foundation of forbidden parallels of fifths and the dissonant fourth. Octavio Agustin has extended the model to microtonal contexts.

In counterpoint, the functional independence of voices is the prime concern. The violation of this principle leads to special effects, which are avoided in counterpoint. In organ registers, certain interval combinations and chords are activated by a single key so that playing a melody results in parallel voice leading. These voices, losing independence, are fused into one and the parallel chords are perceived as single tones with a new timbre. This effect is also used in orchestral arrangements; for instance, in Ravel’s Bolero #5 the parallel parts of flutes, horn and celesta resemble the sound of an electric organ. In counterpoint, parallel voices are prohibited because they violate the homogeneity of musical texture when independent voices occasionally disappear turning into a new timbre quality and vice versa.

Development
Some examples of related compositional techniques include: the round (familiar in folk traditions), the canon, and perhaps the most complex contrapuntal convention: the fugue. All of these are examples of imitative counterpoint.

Examples from the repertoire
There are many examples of song melodies that are harmonically interdependent yet independent in rhythm and melodic contour. For example, "Frère Jacques" and "Three Blind Mice" combine euphoniously when sung together. A number of popular songs that share the same chord progression can also be sung together as counterpoint. A well-known pair of examples is "My Way" combined with "Life on Mars".

Johann Sebastian Bach is revered as one of the greatest masters of counterpoint. For example the harmony implied in the opening subject of the Fugue in G-sharp minor from Book II of the Well-Tempered Clavier is heard anew in a subtle way when a second voice is added. “The counterpoint in bars 5-8... sheds an unexpected light on the tonality of the Subject.” :

Bach's 3-part Invention in F minor combines three independent melodies:

According to pianist András Schiff, Bach's counterpoint influenced the composing of both Mozart and Beethoven. In the development section of the opening movement of Beethoven's Piano Sonata in E minor, Beethoven demonstrates this influence by adding "a wonderful counterpoint" to one of the main themes.

A further example of fluid counterpoint in late Beethoven may be found in the first orchestral variation on the "Ode to Joy" theme in the last movement of Beethoven's Symphony No. 9, bars 116–123. The famous theme is heard on the violas and cellos, while "the basses add a bass-line whose sheer unpredictability gives the impression that it is being spontaneously improvised. Meantime a solo bassoon adds a counterpoint that has a similarly impromptu quality."

In the Prelude to Richard Wagner's opera Die Meistersinger von Nürnberg, three themes from the opera are combined simultaneously. According to Gordon Jacob, "This is universally and justly acclaimed as an extraordinary feat of virtuosity." However, Donald Tovey points out that here "the combination of themes ... unlike classical counterpoint, really do not of themselves combine into complete or euphonious harmony."

One spectacular example of 5-voice counterpoint can be found in the finale to Mozart's Symphony No 41 ("Jupiter" Symphony). Here five tunes combine simultaneously in "a rich tapestry of dialogue": See also Invertible counterpoint.

Species counterpoint
Species counterpoint was developed as a pedagogical tool in which students progress through several "species" of increasing complexity, with a very simple part that remains constant known as the cantus firmus (Latin for "fixed melody"). Species counterpoint generally offers less freedom to the composer than other types of counterpoint and therefore is called a "strict" counterpoint. The student gradually attains the ability to write free counterpoint (that is, less rigorously constrained counterpoint, usually without a cantus firmus) according to the given rules at the time. The idea is at least as old as 1532, when Giovanni Maria Lanfranco described a similar concept in his Scintille di musica (Brescia, 1533). The 16th-century Venetian theorist Zarlino elaborated on the idea in his influential Le institutioni harmoniche, and it was first presented in a codified form in 1619 by Lodovico Zacconi in his Prattica di musica. Zacconi, unlike later theorists, included a few extra contrapuntal techniques, such as invertible counterpoint. In 1725 Johann Joseph Fux published Gradus ad Parnassum (Steps to Parnassus), in which he described five species:

 * 1) Note against note;
 * 2) Two notes against one;
 * 3) Four notes against one;
 * 4) Notes offset against each other (as suspensions);
 * 5) All the first four species together, as "florid" counterpoint.

A succession of later theorists quite closely imitated Fux's seminal work, often with some small and idiosyncratic modifications in the rules. Many of Fux's rules concerning the purely linear construction of melodies have their origin in solfeggi. Concerning the common practice era, alterations to the melodic rules were introduced to enable the function of certain harmonic forms. The combination of these melodies produced the basic harmonic structure, the figured bass.

Considerations for all species
The following rules apply to melodic writing in each species, for each part:

 * 1) The final note must be approached by step. If the final is approached from below, then the leading tone must be raised in a minor key (Dorian, Hypodorian, Aeolian, Hypoaeolian), but not in Phrygian or Hypophrygian mode. Thus, in the Dorian mode on D, a C♯ is necessary at the cadence.
 * 2) Permitted melodic intervals are the perfect unison, fourth, fifth, and octave, as well as the major and minor second, major and minor third, and ascending minor sixth. The ascending minor sixth must be immediately followed by motion downwards.
 * 3) If writing two skips in the same direction—something that must be only rarely done—the second must be smaller than the first, and the interval between the first and the third note may not be dissonant. The three notes should be from the same triad; if this is impossible, they should not outline more than one octave. In general, do not write more than two skips in the same direction.
 * 4) If writing a skip in one direction, it is best to proceed after the skip with step-wise motion in the other direction.
 * 5) The interval of a tritone in three notes should be avoided (for example, an ascending melodic motion F–A–B♮) as is the interval of a seventh in three notes.
 * 6) There must be a climax or high point in the line countering the cantus firmus. This usually occurs somewhere in the middle of exercise and must occur on a strong beat.
 * 7) An outlining of a seventh is avoided within a single line moving in the same direction.

And, in all species, the following rules govern the combination of the parts:

 * 1) The counterpoint must begin and end on a perfect consonance.
 * 2) Contrary motion should dominate.
 * 3) Perfect consonances must be approached by oblique or contrary motion.
 * 4) Imperfect consonances may be approached by any type of motion.
 * 5) The interval of a tenth should not be exceeded between two adjacent parts unless by necessity.
 * 6) Build from the bass, upward.

First species
In first species counterpoint, each note in every added part (parts being also referred to as lines or voices) sounds against one note in the cantus firmus. Notes in all parts are sounded simultaneously, and move against each other simultaneously. Since all notes in First species counterpoint are whole notes, rhythmic independence is not available.

In the present context, a "step" is a melodic interval of a half or whole step. A "skip" is an interval of a third or fourth. (See Steps and skips.) An interval of a fifth or larger is referred to as a "leap".

A few further rules given by Fux, by study of the Palestrina style, and usually given in the works of later counterpoint pedagogues, are as follows.

 * 1) Begin and end on either the unison, octave, or fifth, unless the added part is underneath, in which case begin and end only on unison or octave.
 * 2) Use no unisons except at the beginning or end.
 * 3) Avoid parallel fifths or octaves between any two parts; and avoid "hidden" parallel fifths or octaves: that is, movement by similar motion to a perfect fifth or octave, unless one part (sometimes restricted to the higher of the parts) moves by step.
 * 4) Avoid moving in parallel fourths. (In practice Palestrina and others frequently allowed themselves such progressions, especially if they do not involve the lowest of the parts.)
 * 5) Do not use an interval more than three times in a row.
 * 6) Attempt to use up to three parallel thirds or sixths in a row.
 * 7) Attempt to keep any two adjacent parts within a tenth of each other, unless an exceptionally pleasing line can be written by moving outside that range.
 * 8) Avoid having any two parts move in the same direction by skip.
 * 9) Attempt to have as much contrary motion as possible.
 * 10) Avoid dissonant intervals between any two parts: major or minor second, major or minor seventh, any augmented or diminished interval, and perfect fourth (in many contexts).

In the adjacent example in two parts, the cantus firmus is the lower part. (The same cantus firmus is used for later examples also. Each is in the Dorian mode.)

Second species
In second species counterpoint, two notes in each of the added parts work against each longer note in the given part.

Additional considerations in second species counterpoint are as follows, and are in addition to the considerations for first species:
 * 1) It is permissible to begin on an upbeat, leaving a half-rest in the added voice.
 * 2) The accented beat must have only consonance (perfect or imperfect). The unaccented beat may have dissonance, but only as a passing tone, i.e. it must be approached and left by step in the same direction.
 * 3) Avoid the interval of the unison except at the beginning or end of the example, except that it may occur on the unaccented portion of the bar.
 * 4) Use caution with successive accented perfect fifths or octaves. They must not be used as part of a sequential pattern. The example shown is weak due to similar motion in the second measure in both voices. A good rule to follow: if one voice skips or jumps try to use step-wise motion in the other voice or at the very least contrary motion.

Third species
In third species counterpoint, four (or three, etc.) notes move against each longer note in the given part.

Three special figures are introduced into third species and later added to fifth species, and ultimately outside the restrictions of species writing. There are three figures to consider: The nota cambiata, double neighbor tones, and double passing tones.

Double neighbor tones: the figure is prolonged over four beats and allows special dissonances. The upper and lower tones are prepared on beat 1 and resolved on beat 4. The fifth note or downbeat of the next measure should move by step in the same direction as the last two notes of the double neighbor figure. Lastly a double passing tone allows two dissonant passing tones in a row. The figure would consist of 4 notes moving in the same direction by step. The two notes that allow dissonance would be beat 2 and 3 or 3 and 4. The dissonant interval of a fourth would proceed into a diminished fifth and the next note would resolve at the interval of a sixth.

Fourth species
In fourth species counterpoint, some notes are sustained or suspended in an added part while notes move against them in the given part, often creating a dissonance on the beat, followed by the suspended note then changing (and "catching up") to create a subsequent consonance with the note in the given part as it continues to sound. As before, fourth species counterpoint is called expanded when the added-part notes vary in length among themselves. The technique requires chains of notes sustained across the boundaries determined by beat, and so creates syncopation. A dissonant interval is allowed on beat 1 because of the syncopation created by the suspension. While it is not incorrect to start with a half note, it is also common to start 4th species with a half rest. Short example of "fourth species" counterpoint

Fifth species (florid counterpoint)
In fifth species counterpoint, sometimes called florid counterpoint, the other four species of counterpoint are combined within the added parts. In the example, the first and second bars are second species, the third bar is third species, the fourth and fifth bars are third and embellished fourth species, and the final bar is first species. In florid counterpoint it is important that no one species dominates the composition. Short example of "Florid" counterpoint

Contrapuntal derivations
Since the Renaissance period in European music, much contrapuntal music has been written in imitative counterpoint. In imitative counterpoint, two or more voices enter at different times, and (especially when entering) each voice repeats some version of the same melodic element. The fantasia, the ricercar, and later, the canon and fugue (the contrapuntal form par excellence) all feature imitative counterpoint, which also frequently appears in choral works such as motets and madrigals. Imitative counterpoint spawned a number of devices, including:

 * Melodic inversion: The inverse of a given fragment of melody is the fragment turned upside down—so if the original fragment has a rising major third (see interval), the inverted fragment has a falling major (or perhaps minor) third, etc. (Compare, in twelve-tone technique, the inversion of the tone row, which is the so-called prime series turned upside down.) (Note: in invertible counterpoint, including double and triple counterpoint, the term inversion is used in a different sense altogether. At least one pair of parts is switched, so that the one that was higher becomes lower. See Inversion in counterpoint; it is not a kind of imitation, but a rearrangement of the parts.)
 * Retrograde: Whereby an imitative voice sounds the melody backwards in relation to the leading voice.
 * Retrograde inversion: Where the imitative voice sounds the melody backwards and upside-down at once.
 * Augmentation: When in one of the parts in imitative counterpoint the note values are extended in duration compared to the rate at which they were sounded when introduced.
 * Diminution: When in one of the parts in imitative counterpoint the note values are reduced in duration compared to the rate at which they were sounded when introduced.

Free counterpoint
Broadly speaking, due to the development of harmony, from the Baroque period on, most contrapuntal compositions were written in the style of free counterpoint. This means that the general focus of the composer had shifted away from how the intervals of added melodies related to a cantus firmus, and more toward how they related to each other.

Nonetheless, according to Kent Kennan: "....actual teaching in that fashion (free counterpoint) did not become widespread until the late nineteenth century." Young composers of the eighteenth and nineteenth centuries, such as Mozart, Beethoven, and Schumann, were still educated in the style of "strict" counterpoint, but in practice, they would look for ways to expand on the traditional concepts of the subject.

Main features of free counterpoint:
 * 1) All forbidden chords, such as second-inversion, seventh, ninth etc., can be used freely as long as they resolve to a consonant triad
 * 2) Chromaticism is allowed
 * 3) The restrictions about rhythmic-placement of dissonance are removed. It is possible to use passing tones on the accented beat
 * 4) Appoggiatura is available: dissonance tones can be approached by leaps.

Linear counterpoint
Linear counterpoint is "a purely horizontal technique in which the integrity of the individual melodic lines is not sacrificed to harmonic considerations. "Its distinctive feature is rather the concept of melody, which served as the starting-point for the adherents of the 'new objectivity' when they set up linear counterpoint as an anti-type to the Romantic harmony." The voice parts move freely, irrespective of the effects their combined motions may create." In other words, either "the domination of the horizontal (linear) aspects over the vertical" is featured or the "harmonic control of lines is rejected."

Associated with neoclassicism, the technique was first used in Igor Stravinsky's Octet (1923), inspired by J. S. Bach and Giovanni Palestrina. However, according to Knud Jeppesen: "Bach's and Palestrina's points of departure are antipodal. Palestrina starts out from lines and arrives at chords; Bach's music grows out of an ideally harmonic background, against which the voices develop with a bold independence that is often breath-taking."

According to Cunningham, linear harmony is "a frequent approach in the 20th century...[in which lines] are combined with almost careless abandon in the hopes that new 'chords' and 'progressions'...will result." It is possible with "any kind of line, diatonic or duodecuple".

Dissonant counterpoint
Dissonant counterpoint was originally theorized by Charles Seeger as "at first purely a school-room discipline," consisting of species counterpoint but with all the traditional rules reversed. First species counterpoint must be all dissonances, establishing "dissonance, rather than consonance, as the rule," and consonances are "resolved" through a skip, not step. He wrote that "the effect of this discipline" was "one of purification". Other aspects of composition, such as rhythm, could be "dissonated" by applying the same principle.

Seeger was not the first to employ dissonant counterpoint, but was the first to theorize and promote it. Other composers who have used dissonant counterpoint, if not in the exact manner prescribed by Charles Seeger, include Johanna Beyer, John Cage, Ruth Crawford-Seeger, Vivian Fine, Carl Ruggles, Henry Cowell, Carlos Chávez, John J. Becker, Henry Brant, Lou Harrison, Wallingford Riegger, and Frank Wigglesworth.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Counterpoint


text:
Cyanide

In chemistry, cyanide is a chemical compound that contains a C\tN functional group. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom.

In inorganic cyanides, the cyanide group is present as the cyanide anion −C\tN. This anion is extremely poisonous. Soluble salts such as sodium cyanide (NaCN) and potassium cyanide (KCN) are highly toxic. Hydrocyanic acid, also known as hydrogen cyanide, or HCN, is a highly volatile liquid that is produced on a large scale industrially. It is obtained by acidification of cyanide salts.

Organic cyanides are usually called nitriles. In nitriles, the \sC\tN group is linked by a single covalent bond to carbon. For example, in acetonitrile (CH3\sC\tN), the cyanide group is bonded to methyl (\sCH3). Although nitriles generally do not release cyanide ions, the cyanohydrins do and are thus toxic.

Bonding
The cyanide ion −C\tN is isoelectronic with carbon monoxide -C\tO+ and with molecular nitrogen N≡N. A triple bond exists between C and N. The negative charge is concentrated on carbon C.

In nature
Cyanides are produced by certain bacteria, fungi, and algae. It is an antifeedant in a number of plants. Cyanides are found in substantial amounts in certain seeds and fruit stones, e.g., those of bitter almonds, apricots, apples, and peaches. Chemical compounds that can release cyanide are known as cyanogenic compounds. In plants, cyanides are usually bound to sugar molecules in the form of cyanogenic glycosides and defend the plant against herbivores. Cassava roots (also called manioc), an important potato-like food grown in tropical countries (and the base from which tapioca is made), also contain cyanogenic glycosides.

The Madagascar bamboo Cathariostachys madagascariensis produces cyanide as a deterrent to grazing. In response, the golden bamboo lemur, which eats the bamboo, has developed a high tolerance to cyanide.

The hydrogenase enzymes contain cyanide ligands attached to iron in their active sites. The biosynthesis of cyanide in the NiFe hydrogenases proceeds from carbamoyl phosphate, which converts to cysteinyl thiocyanate, the CN− donor.

Interstellar medium
The cyanide radical •CN has been identified in interstellar space. Cyanogen, (CN)2, is used to measure the temperature of interstellar gas clouds.

Pyrolysis and combustion product
Hydrogen cyanide is produced by the combustion or pyrolysis of certain materials under oxygen-deficient conditions. For example, it can be detected in the exhaust of internal combustion engines and tobacco smoke. Certain plastics, especially those derived from acrylonitrile, release hydrogen cyanide when heated or burnt.

Organic derivatives
In IUPAC nomenclature, organic compounds that have a \sC\tN functional group are called nitriles. An example of a nitrile is acetonitrile, CH3\sC\tN. Nitriles usually do not release cyanide ions. A functional group with a hydroxyl \sOH and cyanide \sCN bonded to the same carbon atom is called cyanohydrin (R2C(OH)CN). Unlike nitriles, cyanohydrins do release poisonous hydrogen cyanide.

Protonation
Cyanide is basic. The pKa of hydrogen cyanide is 9.21. Thus, addition of acids stronger than hydrogen cyanide to solutions of cyanide salts releases hydrogen cyanide.

Hydrolysis
Cyanide is unstable in water, but the reaction is slow until about 170 °C. It undergoes hydrolysis to give ammonia and formate, which are far less toxic than cyanide:
 * CN- + 2 H2O → HCO2- + NH3

Cyanide hydrolase is an enzyme that catalyzes this reaction.

Alkylation
Because of the cyanide anion's high nucleophilicity, cyano groups are readily introduced into organic molecules by displacement of a halide group (e.g., the chloride on methyl chloride). In general, organic cyanides are called nitriles. In organic synthesis, cyanide is a C-1 synthon; i.e., it can be used to lengthen a carbon chain by one, while retaining the ability to be functionalized.
 * RX + CN- → RCN + X-

Redox
The cyanide ion is a reductant and is oxidized by strong oxidizing agents such as molecular chlorine (Cl2), hypochlorite (ClO-), and hydrogen peroxide (H2O2). These oxidizers are used to destroy cyanides in effluents from gold mining.

Metal complexation
The cyanide anion reacts with transition metals to form M-CN bonds. This reaction is the basis of cyanide's toxicity. The high affinities of metals for this anion can be attributed to its negative charge, compactness, and ability to engage in π-bonding.

Among the most important cyanide coordination compounds are the potassium ferrocyanide and the pigment Prussian blue, which are both essentially nontoxic due to the tight binding of the cyanides to a central iron atom. Prussian blue was first accidentally made around 1706, by heating substances containing iron and carbon and nitrogen, and other cyanides made subsequently (and named after it). Among its many uses, Prussian blue gives the blue color to blueprints, bluing, and cyanotypes.

Manufacture
The principal process used to manufacture cyanides is the Andrussow process in which gaseous hydrogen cyanide is produced from methane and ammonia in the presence of oxygen and a platinum catalyst.

 * 2 CH4 + 2 NH3 + 3 O2 → 2 HCN + 6 H2O

Sodium cyanide, the precursor to most cyanides, is produced by treating hydrogen cyanide with sodium hydroxide:
 * HCN + NaOH → NaCN + H2O

Toxicity
Among the most toxic cyanides are hydrogen cyanide (HCN), sodium cyanide (NaCN), potassium cyanide (KCN), and calcium cyanide (Ca(CN)₂). These compounds are extremely poisonous and require careful handling to avoid severe health risks. The cyanide anion is an inhibitor of the enzyme cytochrome c oxidase (also known as aa3), the fourth complex of the electron transport chain found in the inner membrane of the mitochondria of eukaryotic cells. It attaches to the iron within this protein. The binding of cyanide to this enzyme prevents transport of electrons from cytochrome c to oxygen. As a result, the electron transport chain is disrupted, meaning that the cell can no longer aerobically produce ATP for energy. Tissues that depend highly on aerobic respiration, such as the central nervous system and the heart, are particularly affected. This is an example of histotoxic hypoxia.

The most hazardous compound is hydrogen cyanide, which is a gas and kills by inhalation. For this reason, an air respirator supplied by an external oxygen source must be worn when working with hydrogen cyanide. Hydrogen cyanide is produced by adding acid to a solution containing a cyanide salt. Alkaline solutions of cyanide are safer to use because they do not evolve hydrogen cyanide gas. Hydrogen cyanide may be produced in the combustion of polyurethanes; for this reason, polyurethanes are not recommended for use in domestic and aircraft furniture. Oral ingestion of a small quantity of solid cyanide or a cyanide solution of as little as 200 mg, or exposure to airborne cyanide of 270 ppm, is sufficient to cause death within minutes.

Organic nitriles do not readily release cyanide ions, and so have low toxicities. By contrast, compounds such as trimethylsilyl cyanide (CH3)3SiCN readily release HCN or the cyanide ion upon contact with water.

Antidote
Hydroxocobalamin reacts with cyanide to form cyanocobalamin, which can be safely eliminated by the kidneys. This method has the advantage of avoiding the formation of methemoglobin (see below). This antidote kit is sold under the brand name Cyanokit and was approved by the U.S. FDA in 2006.

An older cyanide antidote kit included administration of three substances: amyl nitrite pearls (administered by inhalation), sodium nitrite, and sodium thiosulfate. The goal of the antidote was to generate a large pool of ferric iron (Fe(3+)) to compete for cyanide with cytochrome a3 (so that cyanide will bind to the antidote rather than the enzyme). The nitrites oxidize hemoglobin to methemoglobin, which competes with cytochrome oxidase for the cyanide ion. Cyanmethemoglobin is formed and the cytochrome oxidase enzyme is restored. The major mechanism to remove the cyanide from the body is by enzymatic conversion to thiocyanate by the mitochondrial enzyme rhodanese. Thiocyanate is a relatively non-toxic molecule and is excreted by the kidneys. To accelerate this detoxification, sodium thiosulfate is administered to provide a sulfur donor for rhodanese, needed in order to produce thiocyanate.

Sensitivity
Minimum risk levels (MRLs) may not protect for delayed health effects or health effects acquired following repeated sublethal exposure, such as hypersensitivity, asthma, or bronchitis. MRLs may be revised after sufficient data accumulates.

Mining
Cyanide is mainly produced for the mining of silver and gold: It helps dissolve these metals allowing separation from the other solids. In the cyanide process, finely ground high-grade ore is mixed with the cyanide (at a ratio of about 1:500 parts NaCN to ore); low-grade ores are stacked into heaps and sprayed with a cyanide solution (at a ratio of about 1:1000 parts NaCN to ore). The precious metals are complexed by the cyanide anions to form soluble derivatives, e.g., [Ag(CN)2]- (dicyanoargentate(I)) and [Au(CN)2]- (dicyanoaurate(I)). Silver is less "noble" than gold and often occurs as the sulfide, in which case redox is not invoked (no O2 is required). Instead, a displacement reaction occurs:

The "pregnant liquor" containing these ions is separated from the solids, which are discarded to a tailing pond or spent heap, the recoverable gold having been removed. The metal is recovered from the "pregnant solution" by reduction with zinc dust or by adsorption onto activated carbon. This process can result in environmental and health problems. A number of environmental disasters have followed the overflow of tailing ponds at gold mines. Cyanide contamination of waterways has resulted in numerous cases of human and aquatic species mortality.

Aqueous cyanide is hydrolyzed rapidly, especially in sunlight. It can mobilize some heavy metals such as mercury if present. Gold can also be associated with arsenopyrite (FeAsS), which is similar to iron pyrite (fool's gold), wherein half of the sulfur atoms are replaced by arsenic. Gold-containing arsenopyrite ores are similarly reactive toward inorganic cyanide.

Industrial organic chemistry
The second major application of alkali metal cyanides (after mining) is in the production of CN-containing compounds, usually nitriles. Acyl cyanides are produced from acyl chlorides and cyanide. Cyanogen, cyanogen chloride, and the trimer cyanuric chloride are derived from alkali metal cyanides.

Medical uses
The cyanide compound sodium nitroprusside is used mainly in clinical chemistry to measure urine ketone bodies mainly as a follow-up to diabetic patients. On occasion, it is used in emergency medical situations to produce a rapid decrease in blood pressure in humans; it is also used as a vasodilator in vascular research. The cobalt in artificial vitamin B12 contains a cyanide ligand as an artifact of the purification process; this must be removed by the body before the vitamin molecule can be activated for biochemical use. During World War I, a copper cyanide compound was briefly used by Japanese physicians for the treatment of tuberculosis and leprosy.

Illegal fishing and poaching
Cyanides are illegally used to capture live fish near coral reefs for the aquarium and seafood markets. The practice is controversial, dangerous, and damaging but is driven by the lucrative exotic fish market.

Poachers in Africa have been known to use cyanide to poison waterholes, to kill elephants for their ivory.

Pest control
M44 cyanide devices are used in the United States to kill coyotes and other canids. Cyanide is also used for pest control in New Zealand, particularly for possums, an introduced marsupial that threatens the conservation of native species and spreads tuberculosis amongst cattle. Possums can become bait shy but the use of pellets containing the cyanide reduces bait shyness. Cyanide has been known to kill native birds, including the endangered kiwi. Cyanide is also effective for controlling the dama wallaby, another introduced marsupial pest in New Zealand. A licence is required to store, handle and use cyanide in New Zealand.

Cyanides are used as insecticides for fumigating ships. Cyanide salts are used for killing ants, and have in some places been used as rat poison (the less toxic poison arsenic is more common).

Niche uses
Potassium ferrocyanide is used to achieve a blue color on cast bronze sculptures during the final finishing stage of the sculpture. On its own, it will produce a very dark shade of blue and is often mixed with other chemicals to achieve the desired tint and hue. It is applied using a torch and paint brush while wearing the standard safety equipment used for any patina application: rubber gloves, safety glasses, and a respirator. The actual amount of cyanide in the mixture varies according to the recipes used by each foundry.

Cyanide is also used in jewelry-making and certain kinds of photography such as sepia toning.

Although usually thought to be toxic, cyanide and cyanohydrins increase germination in various plant species.

Human poisoning
Deliberate cyanide poisoning of humans has occurred many times throughout history. Common salts such as sodium cyanide are involatile but water-soluble, so are poisonous by ingestion. Hydrogen cyanide is a gas, making it more indiscriminately dangerous, however it is lighter than air and rapidly disperses up into the atmosphere, which makes it ineffective as a chemical weapon. Poisoning by hydrogen cyanide is more effective in an enclosed space, such as a gas chamber. Most significantly, hydrogen cyanide released from pellets of Zyklon-B was used extensively in the extermination camps of the Holocaust.

Food additive
Because of the high stability of their complexation with iron, ferrocyanides (Sodium ferrocyanide E535, Potassium ferrocyanide E536, and Calcium ferrocyanide E538 ) do not decompose to lethal levels in the human body and are used in the food industry as, e.g., an anticaking agent in table salt.

Chemical tests for cyanide
Cyanide is quantified by potentiometric titration, a method widely used in gold mining. It can also be determined by titration with silver ion. Some analyses begin with an air-purge of an acidified boiling solution, sweeping the vapors into a basic absorber solution. The cyanide salt absorbed in the basic solution is then analyzed.

Qualitative tests
Because of the notorious toxicity of cyanide, many methods have been investigated. Benzidine gives a blue coloration in the presence of ferricyanide. Iron(II) sulfate added to a solution of cyanide, such as the filtrate from the sodium fusion test, gives prussian blue. A solution of para-benzoquinone in DMSO reacts with inorganic cyanide to form a cyanophenol, which is fluorescent. Illumination with a UV light gives a green/blue glow if the test is positive.

title: Cyanide


text:
Carbonate

A carbonate is a salt of carbonic acid, H2CO3, characterized by the presence of the carbonate ion, a polyatomic ion with the formula CO3(2-). The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate group O\dC(\sO\s)2.

The term is also used as a verb, to describe carbonation: the process of raising the concentrations of carbonate and bicarbonate ions in water to produce carbonated water and other carbonated beverages – either by the addition of carbon dioxide gas under pressure or by dissolving carbonate or bicarbonate salts into the water.

In geology and mineralogy, the term "carbonate" can refer both to carbonate minerals and carbonate rock (which is made of chiefly carbonate minerals), and both are dominated by the carbonate ion, CO3(2-). Carbonate minerals are extremely varied and ubiquitous in chemically precipitated sedimentary rock. The most common are calcite or calcium carbonate, CaCO3, the chief constituent of limestone (as well as the main component of mollusc shells and coral skeletons); dolomite, a calcium-magnesium carbonate CaMg(CO3)2; and siderite, or iron(II) carbonate, FeCO3, an important iron ore. Sodium carbonate ("soda" or "natron"), Na2CO3, and potassium carbonate ("potash"), K2CO3, have been used since antiquity for cleaning and preservation, as well as for the manufacture of glass. Carbonates are widely used in industry, such as in iron smelting, as a raw material for Portland cement and lime manufacture, in the composition of ceramic glazes, and more. New applications of alkali metal carbonates include: thermal energy storage, catalysis and electrolyte both in fuel cell technology as well as in electrosynthesis of H2O2 in aqueous media.

Structure and bonding
The carbonate ion is the simplest oxocarbon anion. It consists of one carbon atom surrounded by three oxygen atoms, in a trigonal planar arrangement, with D3h molecular symmetry. It has a molecular mass of 60.01 g/mol and carries a total formal charge of −2. It is the conjugate base of the hydrogencarbonate (bicarbonate) ion, HCO3-, which is the conjugate base of H2CO3, carbonic acid.

The Lewis structure of the carbonate ion has two (long) single bonds to negative oxygen atoms, and one short double bond to a neutral oxygen atom.

 * Carbonate-ion-localised-2D.png

This structure is incompatible with the observed symmetry of the ion, which implies that the three bonds are the same length and that the three oxygen atoms are equivalent. As in the case of the isoelectronic nitrate ion, the symmetry can be achieved by a resonance among three structures:

 * Carbonate-ion-resonance-2D.png

This resonance can be summarized by a model with fractional bonds and delocalized charges:

 * Carbonate-ion-delocalised-partial-charges-2D.png Carbonate-3D-vdW.png

Chemical properties
Metal carbonates generally decompose on heating, liberating carbon dioxide leaving behind an oxide of the metal. This process is called calcination, after calx, the Latin name of quicklime or calcium oxide, CaO, which is obtained by roasting limestone in a lime kiln:
 * CaCO3 → CaO + CO2

As illustrated by its affinity for Ca(2+), carbonate is a ligand for many metal cations. Transition metal carbonate and bicarbonate complexes feature metal ions covalently bonded to carbonate in a variety of bonding modes.

Lithium, sodium, potassium, rubidium, caesium, and ammonium carbonates are water-soluble salts, but carbonates of 2+ and 3+ ions are often poorly soluble in water. Of the insoluble metal carbonates, CaCO3 is important because, in the form of scale, it accumulates in and impedes flow through pipes. Hard water has the source of this material.

Acidification of carbonates generally liberates carbon dioxide:
 * CaCO3 + 2 HCl → CaCl2 + CO2 + H2O

Thus, scale can be removed with acid.

In solution the equilibrium between carbonate, bicarbonate, carbon dioxide and carbonic acid is sensitive to pH, temperature, and pressure. Although di- and trivalent carbonates have low solubility, bicarbonate salts are far more soluble. This difference is related to the disparate lattice energies of solids composed of mono- vs dianions, as well as mono- vs dications.

In aqueous solution, carbonate, bicarbonate, carbon dioxide, and carbonic acid participate in a dynamic equilibrium. In strongly basic conditions, the carbonate ion predominates, while in weakly basic conditions, the bicarbonate ion is prevalent. In more acid conditions, aqueous carbon dioxide, CO2(aq), is the main form, which, with water, H2O, is in equilibrium with carbonic acid – the equilibrium lies strongly towards carbon dioxide. Thus sodium carbonate is basic, sodium bicarbonate is weakly basic, while carbon dioxide itself is a weak acid.

Organic carbonates
In organic chemistry a carbonate can also refer to a functional group within a larger molecule that contains a carbon atom bound to three oxygen atoms, one of which is double bonded. These compounds are also known as organocarbonates or carbonate esters, and have the general formula R\sO\sC(\dO)\sO\sR′, or RR′CO3. Important organocarbonates include dimethyl carbonate, the cyclic compounds ethylene carbonate and propylene carbonate, and the phosgene replacement, triphosgene.

Buffer
Three reversible reactions control the pH balance of blood and act as a buffer to stabilise it in the range 7.37–7.43:

 * 1) H+ + HCO3- ⇌ H2CO3
 * 2) H2CO3 ⇌ CO2(aq) + H2O
 * 3) CO2(aq) ⇌ CO2(g)

Exhaled CO2(g) depletes CO2(aq), which in turn consumes H2CO3, causing the equilibrium of the first reaction to try to restore the level of carbonic acid by reacting bicarbonate with a hydrogen ion, an example of Le Châtelier's principle. The result is to make the blood more alkaline (raise pH). By the same principle, when the pH is too high, the kidneys excrete bicarbonate (HCO3-) into urine as urea via the urea cycle (or Krebs–Henseleit ornithine cycle). By removing the bicarbonate, more H+ is generated from carbonic acid (H2CO3), which comes from CO2(g) produced by cellular respiration.

Crucially, a similar buffer operates in the oceans. It is a major factor in climate change and the long-term carbon cycle, due to the large number of marine organisms (especially coral) which are made of calcium carbonate. Increased solubility of carbonate through increased temperatures results in lower production of marine calcite and increased concentration of atmospheric carbon dioxide. This, in turn, increases Earth temperature. The amount of CO3(2-) available is on a geological scale and substantial quantities may eventually be redissolved into the sea and released to the atmosphere, increasing CO2 levels even more.

Carbonate salts

 * Carbonate overview:

Presence outside Earth
It is generally thought that the presence of carbonates in rock is strong evidence for the presence of liquid water. Recent observations of the planetary nebula NGC 6302 show evidence for carbonates in space, where aqueous alteration similar to that on Earth is unlikely. Other minerals have been proposed which would fit the observations.

Until recently carbonate deposits have not been found on Mars via remote sensing or in situ missions, even though Martian meteorites contain small amounts. Groundwater may have existed at Gusev and Meridiani Planum.

title: Carbonate