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Damaschke Field

Damaschke Field, officially Dutch Damaschke Stadium, is a sports playing field and stadium in Oneonta, New York. Primarily used for baseball, the field has been a municipal landmark for over a hundred years.

History
The original baseball field was officially opened on Memorial Day in 1905 under the name Elm Park. Numerous stars from the early years of US baseball, including Babe Ruth and Rogers Hornsby, drew large crowds at the field for semi-pro and exposition games. A permanent steel grandstand was erected for spectators in 1938.

In August 1968, the city renamed the site as Dutch Damaschke Stadium to honor local sports coach, referee, and counselor Ernest C. "Dutch" Damaschke, who had served as Oneonta's Recreation Commissioner for more than thirty years. The field and stadium are administered as public facilities within Oneonta's large Neahwa Park.

The site was the longtime home of the area's minor league baseball team, the Oneonta Red Sox (1966), Oneonta Yankees (1967–1998), Oneonta Tigers (1999–2009). The field has also regularly hosted the Oneonta Indians football team, the Oneonta United soccer team, and the Hartwick College baseball team. It is currently the home field of the Oneonta Outlaws, a collegiate summer baseball team in the Perfect Game Collegiate Baseball League.

A few games were staged here in late May of 1973 by the Syracuse Chiefs of the International League while their home field MacArthur Stadium was being repaired after a fire.

title: Damaschke Field


text:
Talk:Roobarb

Roobarb and Custard
copied from User talk:GRAHAMUK

''Hi I came across Roobarb and Custard created by you when it came up on discussion at reference desk. I'm planning to create an article on the "Roobarb and Custard effect" and would like to know your initial source of the Roobarb article and how the animation style came to be called by this name. Thanks. Jay 6 July 2005 06:41 (UTC)''

 * Most of the reference for this article came from an exhibition at the Museum of Film and Television in Bradford, Yorkshire. I'm not sure if the exhibition was permanent or temporary, it was a good few years back. Well worth visiting if you're ever in the area. Graham 8 July 2005 12:48 (UTC)

 * Does anyone know if I can find online material anywhere for the "Roobarb and Custard effect" ? Jay 16:52, 18 July 2005 (UTC)

 * I don't believe "Roobarb and Custard effect" has become a term used in the animation industry. Google only returns 2 results for the phrase, and surprise surprise, they're both from this article. I'm removing this text unless anyone can cite a veifiable source for this term The jiggly effect was new, and any similar effect in animation is called the "Roobarb and Custard effect" to this day.  --Psychonaut3000 00:54, 26 June 2006 (UTC)

 * Oh well, I've to go back to looking for a name for the 'effect'. Jay 18:48, 12 August 2006 (UTC)
 * The name is Squigglevision. Jay (talk) 14:59, 11 June 2012 (UTC)

Colour
Is Roobarb green? I thought he was yellow. Can we attempt some form of consensus on the colour? Chrisbrennan 05:10, 12 April 2006
 * At the start of 'When it wasn't Thorsday' Roobarb describes himself as green, and in the picture on the article page he's clearly much greener than his yellow beak. Can we go with green? Squiddy | (squirt ink?)  11:14, 9 September 2010 (UTC)

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

title: Talk:Roobarb


text:
Tarzan the Ape Man (1932 film)

Tarzan the Ape Man is a 1932 pre-Code American action adventure film released by Metro-Goldwyn-Mayer featuring Edgar Rice Burroughs' famous jungle hero Tarzan and starring Johnny Weissmuller, Neil Hamilton, C. Aubrey Smith and Maureen O'Sullivan. It was Weissmuller's first of 12 Tarzan films. O'Sullivan played Jane in six features between 1932 and 1942. The film is loosely based on Burroughs' 1912 novel Tarzan of the Apes, with the dialogue written by Ivor Novello. The film was directed by W.S. Van Dyke. Metro-Goldwyn-Mayer released two remakes of Tarzan, the Ape Man in 1959 and in 1981, but each was a different adaptation of Rice Burroughs' novel. It is also the first appearance of Tarzan's famous yell.

Plot
James Parker and Harry Holt travel in Africa on a quest for the legendary elephant burial grounds and their ivory. They are joined by Parker's daughter Jane. Holt is attracted to Jane, and tries somewhat ineffectively to protect her from the jungle's dangers. The expedition encounters an attack by both hippopotami and crocodiles. The mysterious Tarzan wards off the attack, but abducts Jane.

The experience is terrifying to Jane at first, but as their relationship develops, she finds herself happy; "not a bit afraid, not a bit sorry". As she returns to her father, her feelings are brought to a test. She wants Tarzan to come with her to London, and to be part of her world. But Tarzan turns his back on her and returns to the jungle. Her father tells her that is where Tarzan belongs; she cries, "not now, he belongs to me."

The expedition is captured by a tribe of aggressive dwarfs. Jane sends Tarzan's chimpanzee friend Cheeta (Jiggs) for help, bringing Tarzan to their rescue. During the rescue, Tarzan summons elephants and they escape from the dwarfs' stronghold, although Jane's father dies from wounds just as they reach the elephant graveyard. Jane decides to stay in the jungle with Tarzan and in the final scene, to the music of Tchaikovsky's Romeo and Juliet, the happy couple appear on a rock, Jane holding Cheeta like a baby.

Cast

 * Johnny Weissmuller as Tarzan
 * Maureen O'Sullivan as Jane Parker
 * Neil Hamilton as Harry Holt
 * C. Aubrey Smith as James Parker
 * Doris Lloyd as Mrs Cutten
 * Forrester Harvey as Beamish
 * Ivory Williams as Riano
 * Ray Corrigan as Ape
 * Johnny Eck as Bird Creature
 * Angelo Rossitto as Evil Dwarf (uncredited)

Production
MGM finally found who they were looking for when they came across decorated Olympian Weissmuller. The professional swimmer had five gold medals in the 1924 and 1928 Olympics, alongside 67 world and 52 national titles. The only obstacle with signing him onto the role was his contract to model BVD underwear. In order for them to release him from the contract, MGM agreed to have actresses such as Greta Garbo and Marie Dressler, to be featured in BVD ads.

The film was shot on Lot One of the Metro-Goldwyn-Mayer studios in Culver City, California and at the Lake Sherwood area north of Los Angeles as well as Silver Springs in Florida. Lions from the film were borrowed from nearby Goebel's Lion Farm in Thousand Oaks, CA. Goebel himself would often camp by the filming site near Lake Sherwood to watch his lions during filming.

As with most Weissmuller Tarzan films, the elephants were Indian, which have smaller ears, rather than African, so large fake ears, and fake tusks, were fitted onto the animals in an attempt to make them look authentic. Similarly, the tribe of African dwarfs, made to look like pygmies (all males), portrayed in the film was actually a cast of several white midgets wearing blackface.

Stock footage made in Africa for W.S. Van Dyke's Trader Horn was added to location work shot in the then-undeveloped Toluca Lake region north of Los Angeles.

Release
The film was released on April 2, 1932.

Reception
The movie proved to be a huge hit, pulling in nearly $1 million in profits. The overall success of the film led MGM to star Weissmuller and O'Sullivan in a total of five sequels.

Film review aggregator Rotten Tomatoes reported an approval rating of 100% "Fresh", based on 14 reviews, with a rating average of 7.9/10.

Film series
The Tarzan the Ape Man (1932) sequels that were produced by MGM, starred Johnny Weissmuller and Maureen O'Sullivan, were:
 * Tarzan and His Mate (1934)
 * Tarzan Escapes (1936)
 * Tarzan Finds a Son! (1939)
 * Tarzan's Secret Treasure (1941)
 * Tarzan's New York Adventure (1942)

The Tarzan sequels that were produced by RKO, starred Johnny Weissmuller were:
 * Tarzan Triumphs (1943)
 * Tarzan's Desert Mystery (1943)
 * Tarzan and the Amazons (1945)
 * Tarzan and the Leopard Woman (1946)
 * Tarzan and the Huntress (1947)
 * Tarzan and the Mermaids (1948)

Following the twelve films starring Johnny Weissmuller, MGM and RKO would produce a further 16 Tarzan films set in the same continuity with different actors playing Tarzan, along with two remake films in 1959 (starring Denny Miller as Tarzan) and 1981 (starring Bo Derek as Jane). • Lex Barker

• * Tarzan's Magic Fountain (1949)

• * Tarzan and the Slave Girl (1950)

• * Tarzan's Peril (1951)

• * Tarzan's Savage Fury (1952)

• * Tarzan and the She-Devil (1953)

• Gordon Scott

• * Tarzan's Hidden Jungle (1955)

• * Tarzan and the Lost Safari (1957)

• * Tarzan and the Trappers (1958)

• * Tarzan's Fight for Life (1958)

• * Tarzan's Greatest Adventure (1959)

• * Tarzan the Magnificent (1960)

• Jock Mahoney

• * Tarzan Goes to India (1962)

• * Tarzan's Three Challenges (1963)

• Mike Henry

• * Tarzan and the Valley of Gold (1966)

• * Tarzan and the Great River (1967)

• * Tarzan and the Jungle Boy (1968)

title: Tarzan the Ape Man (1932 film)


text:
User:Brat32

I'm gone.

title: User:Brat32


text:
William Murray, 8th Earl of Mansfield

William David Mungo James Murray, 8th Earl of Mansfield, 7th Earl of Mansfield, (7 July 1930 – 21 October 2015), styled Lord Scone until 1970, was a British nobleman and Conservative politician.

Biography
William Murray was born on 7 July 1930. He was the only son of Mungo Murray, 7th Earl of Mansfield and Mansfield, and his wife Dorothea Helena, younger daughter of Sir Lancelot Carnegie. He was educated at Eton College and Christ Church, Oxford. He served with the Scots Guards in Malaya from 1949 to 1950. He was called to the bar, Inner Temple, in 1958.

Murray was a barrister from 1958 until 1971, when he succeeded his father as Earl of Mansfield.

He was a member of the British Delegation to the European Parliament from 1973 to 1975 (prior to the direct election of Members of the European Parliament), and was an opposition spokesman in the House of Lords from 1975 to 1979. He was a Minister of State in the Scottish Office from 1979 to 1983 and in the Northern Ireland Office from 1983 to 1984.

He was appointed an Honorary Sheriff of Perthshire in 1974, a Justice of the Peace in 1975 and a Deputy Lieutenant for Perth and Kinross in 1980.

Murray has also held a number of business and charitable appointments, such as serving as first president of the Federation of Hunting Associations of the European Communities (FACE) from 1977 to 1979.

He was the first President of the Scottish Association for the Care and Resettlement of Offenders and from 1985 to 1996 served as First Crown Estate Commissioner.

He succeeded as the 11th Lord Balvaird on 2 September 1971 and he succeeded as the 13th Lord Scone on 2 September 1971. He was also the feudal Baron of Balvaird.

Marriage and children
Murray married Pamela Joan Foster on 19 December 1955. They had three children:

The Countess was a Patroness of the Royal Caledonian Ball. She died on 2 October 2022, at the age of 87.
 * Alexander David Mungo Murray, 9th Earl of Mansfield and Mansfield (born 17 October 1956)
 * Lady Georgina Dorothea Mary Murray (born 10 March 1967), married to John Bullough
 * Hon James William Murray (born 7 June 1969)

Death
Murray died on 21 October 2015 and his funeral and memorial service were held at St John's Kirk of Perth on 30 October 2015, with a wake at Scone Palace. He was succeeded by his son Alexander David Mungo Murray.

title: William Murray, 8th Earl of Mansfield


text:
Oregon Contemporary

Oregon Center for Contemporary Art (also known as Oregon Contemporary, formerly Disjecta) is an art center in Portland, Oregon. It is home to the Portland Biennial since 2010, continuing in the tradition of the Portland Art Museum's ended Oregon Biennial.

Programming
Oregon Contemporary's Curator in Residence program began in 2011 and is the first of its kind in the region. Curators include Lucy Cotter (2021–22), Justin Hoover (2019–20), Suzy Halajian (2018-19), Julia Greenway (2017–18), Michele Fiedler (2016-17), Chiara Giovando (2015–16), Rachel Adams (2014-15), Summer Guthery (2013–14), Josephine Zarkovich (2012–13), and Jenene Nagy (2011-12).

Visual arts programming highlights include solo exhibitions by Natalie Ball, Avantika Bawa, Karl Burkheimer, Tannaz Farsi, Anna Fidler, Chris Fraser, Dan Gilsdorf, Peter Halley, Mark Licari, and Jenene Nagy.

In 2010 (then known as Disjecta), Oregon Contemporary launched the first Portland Biennial. The Biennial, which originated at the Portland Art Museum in 1949, is a major survey of Oregon artists who define and advance the state's contemporary arts landscape. The Portland 2019 Biennial was curated by a group of three regional curators–Yaelle S. Amir, Elisheba Johnson, and Ashley Stull-Meyers. The Biennial received positive reviews particularly for including new, diverse voices and a wider curatorial scope than previous biennials.

Past curators of the Biennial include Cris Moss (2010), Prudence F. Roberts (2012), Amanda Hunt (2014), and Michelle Grabner (2016).

History
Oregon Contemporary, was founded under the name, 'Disjecta' as a non-profit art organization in 2005 with the goals of moving to an expanded 20,000 sf space in North Park Blocks. The plans were launched with a high profile party. Disjecta then moved to the Templeton Building on what is now known as the Burnside Bridgehead.

In 2008, Disjecta announced the public opening of a 20,000 sf facility at 8371 N Interstate in the historic Kenton neighborhood. The center now houses five fully leased artist studios, along with 3,500 square feet of visual exhibition space, a 600 sf performance space, and an open space that houses performances and community events.

In 2016, Disjecta announced the departure of founder, Bryan Suereth, amid some mild controversy. The board hired Blake Shell as executive director in April 2017. On June 14, 2021, Disjecta was officially renamed the Oregon Center for Contemporary Art (or Oregon Contemporary, for short).

title: Oregon Contemporary


text:
Integrated Electronic Control Centre

The Integrated Electronic Control Centre (IECC) was developed in the late 1980s by the British Rail Research Division for UK-based railway signalling centres, although variations exist around the world. It is the most widely deployed VDU based signalling control system in the UK, with over 50 workstations in control centres that manage many of the most complex and busy areas of the network.

IECC consists of a number of operator’s workstations with VDU/LCD displays which depict the control area and is semi-automatic using Automatic Route Setting (ARS) – a computer-based route setting system driven from a pre-programmed timetable database. ARS can also handle severely disrupted service patterns and assist the signaller in the event of train or infrastructure failures.

IECCs were developed as an alternative to the traditional switch or button panel control, which in turn replaced mechanical lever frames. From the start, they controlled Solid State Interlockings (SSIs), a software version of the traditional relay interlocking, but existing relay interlockings may also be controlled from an IECC. The system can control as many miles of track as required, but typically around 50–100 miles.

Recently, PC-based control systems, similar to the IECC have been developed and are sold by various signalling contractors, e.g. Westinghouse Rail Systems WESTCAD.

Early history
The concept of IECC was developed at the Railway Technical Centre in Derby during the 1980s, and in particular the initial software for ARS and SSI.

A contract for the development of an operational standard system was let in January 1987 to CAP Group, including the supply of a complete system for Yoker (Glasgow) and the ARS for the Waterloo area. This was the first time a software house became involved in railway signalling after competing against the main incumbent suppliers of GEC-General Signal and Westinghouse Signals Ltd. The solution used off-the-shelf microcomputer technology (Motorola 68000 microprocessors and VME Bus) to host the sub-systems of IECC in high availability configurations linked via a duplicated Nine Tiles Superlink local area network. Subsequent contracts were let to CAP Group (became Sema Group in 1988) for further operational IECC systems involving the supply of turnkey hardware and software. These included the first IECC to go live at Liverpool Street in Easter 1989 quickly followed by York. In September 2020 the original Liverpool Street IECC was replaced with a new IECC Scalable system.

Later developments
As a result of UK railway privatisation in the mid-1990s, British Rail Research was bought by AEA Technology Rail, who took over the supply of new IECCs, support for the existing installed base, and enhancements to the hardware and software. In 2006, the AEA rail business became DeltaRail (now called Resonate Group), who have developed IECC Scalable which replicates all the functionality of the original IECC on a modern hardware platform and software architecture. Following a successful six-month trial at Swindon B in 2012, IECC Scalable is now the standard for new installations, starting with Cambridge where it controls the Ely-Norwich line which has been resignalled on the "modular signalling" concept for secondary routes.

List of IECCs in service as of 9 January 2024
The following installations are not true IECCs of the BR/SEMA/DeltaRail design. They are VDU based signalling control systems with a similar "look and feel" but in most cases they do not incorporate Automatic Route Setting.

Some locations shown below are interim installations which will eventually move into larger signalling control centres, such as Leamington and Madeley, which in time will move to the West Midlands Signalling Centre.

title: Integrated Electronic Control Centre


text:
Frederick James Hargreaves

Frederick James Hargreaves (10 February 1891 – 4 September 1970) was a British astronomer and optician.

He was considered the foremost optician in Britain, and was noted for his skill in mirror making and other optics for astronomical telescopes. He also made a series of observations and drawings of the turbulence in the belts and zones of Jupiter's atmosphere.

He served as president of the British Astronomical Association (1942-1944).

He partnered to create the firm Cox Hargreaves and Thompson, with first premises under the embankment of the mainline station near Preston Park, Brighton, Sussex. Later, moving to the much better environment for really accurate grinding and surface continuity at the large tunnel layout (Deep Level Air Raid Shelter No. 4), in the grounds of Cane Hill Asylum, Coulsdon, Surrey, from 1952-1970. Cut deep into a chalk hill, these brick-lined tunnels had an all-year round constant temperature and absolutely no vibration. Mirrors tested at point of manufacture and later using modern testing equipment have shown Hargreaves' hand-cut mirrors to be accurate to an average of 3 wavelengths of sodium light.

Hargreaves trained telescope-maker Norman Fisher (1936-1994) in mirror making at the Cane Hill tunnels. The Norman Fisher Observatory is sited at Kenley, Surrey.

Awards and honors

 * Awarded the Jackson-Gwilt Medal in 1938.
 * The crater Hargreaves on the Moon is named after him.

title: Frederick James Hargreaves


text: User talk:68.49.12.253

title: User talk:68.49.12.253


text:
Saint-Pierre-de-Plesguen

Saint-Pierre-de-Plesguen (Sant-Pêr-Plewenn) is a former commune in the Ille-et-Vilaine department in Brittany in northwestern France. On 1 January 2019, it was merged into the new commune Mesnil-Roc'h.

Personalities
Hughes Felicité Robert de Lamennais lived in Saint-Pierre-de-Plesguen during the 19th century.

Population
Inhabitants of Saint-Pierre-de-Plesguen are called saint-pierrais in French.

title: Saint-Pierre-de-Plesguen


text:
Acrolepiidae

The Acrolepiidae are a family of moths known as false diamondback moths. In modern classifications, they are often treated as a subfamily (Acrolepiinae) of the family Glyphipterigidae.

Caterpillars are typically spotted and 10 to 12 mm in length. Adults have a wingspan between 16 and 18 mm and are generally nocturnal.

Species
Some representative species are:

 * Acrolepia aiea, Swezey 1933
 * Acrolepia alliella, Sato 1979
 * Acrolepia autumnitella, Curtis 1838
 * Acrolepia nothocestri, Busck 1914
 * Acrolepiopsis assectella, Zeller, 1839
 * Acrolepiopsis betulella, Curtis 1838
 * Acrolepiopsis incertella, Chambers 1872
 * Acrolepiopsis marcidella, Curtis 1850
 * Acrolepiopsis sapporensis, Matsumura 1931
 * Acrolepiopsis tauricella, Staudinger 1870
 * Acrolepiopsis vesperella, Zeller 1850
 * Digitivalva arnicella, Heyden 1863
 * Digitivalva eglanteriella, Mann 1855
 * Digitivalva granitella, Treitschke 1833
 * Digitivalva occidentella, Klimesch 1956
 * Digitivalva pulicariae, Klimesch 1956
 * Digitivalva reticulella, Hübner 1796

title: Acrolepiidae


text: Category:Israeli art

title: Category:Israeli art


text:
Jeju language

Jeju (Jeju: 제줏말; Jeju RR:, or , or ), often called Jejueo or Jejuan in English-language scholarship, is a Koreanic language originally from Jeju Island, South Korea. It is not mutually intelligible with mainland Korean dialects. While it was historically considered a divergent Jeju dialect of the Korean language, it is increasingly referred to as a separate language in its own right. It is declining in usage and was classified by UNESCO in 2010 as critically endangered, the highest level of language endangerment possible. Revitalization efforts are ongoing.

The consonants of Jeju are similar to those of Seoul Korean, but Jeju has a larger and more conservative vowel inventory. Jeju is a head-final, agglutinative, suffixing language like Korean. Nouns are followed by particles that may function as case markers. Verbs inflect for tense, aspect, mood, evidentiality, relative social status, formality, and other grammatical information. Korean and Jeju differ significantly in their verbal paradigms. For instance, the continuative aspect marker of Jeju and the mood or aspect distinction of many Jeju connective suffixes are absent in Korean. Most of the Jeju lexicon is Koreanic, and the language preserves many Middle Korean words now lost in Standard Korean. Jeju may also have a Peninsular Japonic substratum, but this argument has been disputed.

Jeju was already divergent from the Seoul dialect of Korean by the fifteenth century and unintelligible to mainland Korean visitors by the sixteenth century. The language was severely undermined by the Jeju uprising of 1948, the Korean War, and the modernization of South Korea. Many fluent speakers remaining in Jeju Island are now over seventy years old. Most people in Jeju Island now speak a variety of Korean with a Jeju substratum. The language may be somewhat more vigorous in a diaspora community in Osaka, Japan, as many Jeju people migrated to Osaka in the 1920s, but even there, younger members of the community tend to speak Japanese.

Nomenclature and relationship to Korean

Various terms in both Korean and English exist for the Jeju language, which also vary depending on whether it is considered a separate language or a dialect of Korean by the speaker.

Among native speakers, the term "Jeju speech" is most commonly used. In English-language scholarship, it is often called Jejueo or Jejuan.

Language or dialect distinction
Jeju is closely related to Korean. It was traditionally considered an especially divergent dialect of Korean, and is still referred to as such by the National Institute of the Korean Language and the South Korean Ministry of Education.

Until the 2000s, South Korean academia preferred the term "Jeju dialect". While the term "Jeju language" was first used in 1947, it was not until the mid-1990s that the term gained traction. The majority of South Korean academic publications switched to using "Jeju language" by the early 2010s. Since somewhat earlier, "Jeju language" has also been the term preferred in local law, such as the 2007 Language Act for the Preservation and Promotion of the Jeju Language, and by non-governmental organizations working to preserve the language. The only English-language monograph on Jeju, published in 2019, consistently refers to it as a language as well.

Mutual intelligibility with modern South Korean Korean
Jeju is not mutually intelligible with even the southernmost dialects of South Korea. In a 2014 survey measuring intelligibility, Korean speakers from three different dialect zones (Seoul, Busan, and Yeosu) were exposed to one minute of spoken Jeju, with a control group of native Jeju speakers. On average, South Korean native speakers from all three dialect zones answered less than 10% of the basic comprehension questions correctly, while native Jeju speakers answered over 89% of the questions correctly. These results are comparable to the results of an intelligibility test of Norwegian for native Dutch speakers. Diaspora Jeju speakers living in Japan have also reported that they find it difficult to understand South Korean news media, and resort to Japanese subtitles when watching South Korean TV shows.

Geographic distribution
Jeju was traditionally spoken throughout Jeju Province except in the Chuja Islands, halfway between Jeju Island and mainland Korea, where a variety of Southwestern Korean is found. The language is also used by some of the first- and second-generation members of the Zainichi Korean community in Ikuno-ku, Osaka, Japan.

Compared to mainland Korean dialect groups, there is little internal variation within Jeju. A distinction between a northern and southern dialect with a geographic divide at Hallasan is sometimes posited, but an eastern-western dialectal divide cutting through Jeju City and Seogwipo may better explain the few dialectal differences that do exist. A 2010 survey of regional variation in 305 word sets suggests that the north–south divide and the east–west divide coexist, resulting in four distinct dialect groups.

Pre-modern history
The Koreanic languages are likely not native to Jeju Island; it has been proposed that the family has its roots in Manchuria, a historical region in northeastern Asia. It is thought that Koreanic speakers migrated from southern Manchuria between the third and eighth centuries CE. Linguist Alexander Vovin suggests that the ancient kingdom of Tamna, which ruled the island until the twelfth century, may have spoken a Japonic language that left a substrate influence on Jeju. When exactly this putative Japonic language may have been replaced by the Koreanic ancestor of Jeju remains unclear.

Unlike mainland Korea, which was ruled only indirectly by the Mongols, Jeju was placed under direct Yuan administration in the late thirteenth century. Significant numbers of Mongol soldiers migrated to the island during this period, and their language acted as a superstratum that may have accelerated local language change. Linguist Yang Changyong speculates that the formation of Jeju as a language independent of Korean was influenced by Mongol.

During the late thirteenth century, Jeju Island came under direct Yuan administration, which lead to significant migration of Mongol soldiers to the island. Acting as a superstratum, their language contributed to the change of the local language. Yang Changyong, a linguist, speculates that Mongol influence played a significant role in the formation of Jejueo as a distinct language independent from standard Korean.

By the fifteenth century, when the invention of Hangul greatly improved the understanding of Korean phonology, Seoul Korean and Jeju were already divergent; the Seoul prestige dialect of fifteenth-century Middle Korean disallowed the diphthong, which Jeju allows. Sixteenth- and seventeenth-century references to the language of Jeju by mainland Korean literati state that it was already unintelligible to mainland Koreans. Kim Sang-heon (1570―1652), who from 1601 to 1602 served as the island's pacification commissioner, gives six words in the "provincial language" with clear cognates in modern Jeju and also writes:

謫人 申長齡 乃譯官也 嘗曰 「比島語音 酷以中華 如驅牛馬之聲 尤不可分辯云云 盖風氣與華不隔而然耶 曾爲元朝所據置官於此故與華相雜而然耶」... 所謂俚語者 但高細不可曉

"The exiled man Shin Jangnyeong was originally a government interpreter. He said, 'The language of this island is most like Chinese, and the sounds they make while driving cattle and horses are yet more impossible to tell apart. Is this because the climate is not far from that of China, or because the Yuan dynasty once ruled and appointed officials here and the Chinese mingled with them?'... What is called the provincial language is but high and thin and cannot be understood."

In 1629, the Korean government banned the emigration of Jeju Islanders to the mainland, further restricting linguistic contacts between Jeju and Korean. At the same time, the island was also used throughout the Joseon era (1392―1910) as a place of exile for disgraced scholar-officials. These highly educated speakers of Seoul Korean often tutored the children of their Jeju neighbors during their exile and established a continuous and significant Seoul Korean superstratum in Jeju.

Japanese colonial period (1910–1945)
Under the Japanese colonial rule, Jejueo remained the dominating language in both public and private spheres on Jeju Island. However, with the entrance of Japanese loanwords to the lexicon, some speakers became monolingual Japanese speakers. Migration of Jeju Islanders to Japan began to skyrocket in 1911, with significant communities established, more so in cities like Osaka, becoming home to 38,000 Jeju Islanders by 1911. Despite gaining independence, citizens of Jeju and Korea still migrated to Japan, continuing to impact the linguistic landscape of Jeju Island as the younger generations within the diaspora communities only spoke Japanese, leading the decline in fluency in Jejueo.

Modern period and decline (1945–present)
Severe disruption to the Jeju language community began after the end of Japanese rule and World War II in 1945. Korea was divided between an American government in the South and a Soviet government in the north, which were succeeded by South Korea and North Korea correspondingly in 1948. Popular opposition to the division and many other issues led to a rebellion on Jeju island on 3 April 1948. The Syngman Rhee regime suppressed the rebellion with mass killings of civilians. As many as 60,000 Jeju Islanders, or a full fifth of the pre-rebellion population, were killed. 40,000 more fled to Japan. Out of the 400 villages of the island, only 170 remained.

The devastating impact of the massacres on the Jeju language community was exacerbated by the outbreak of the Korean War in 1950. While Jeju was never occupied by the North Korean army, nearly 150,000 Korean-speaking refugees from the mainland fleeing North Korean invasion arrived in Jeju in the first year of the war.

The above events shattered the Jeju language's former dominance on the island, and Standard Korean began to displace Jeju in the public sphere by the 1950s. The 1970s Saemaeul Undong, an ambitious rural modernization program launched by Park Chung Hee, disrupted the traditional village community where Jeju had thrived. The language came to be perceived as an incorrect dialect of Korean; students were even subject to corporal punishment if they used it in school. Standard Korean became more commonplace in private settings even outside of Jeju City. The language attitude of native Jeju speakers in this period was self-disparaging, and even Jeju people regarded the use of Jeju "with contempt." A 1981 survey of language attitudes among high school and university students natively speaking Seoul Korean, Chungcheong Korean, Southwestern Korean, Southeastern Korean, and Jeju showed that Jeju speakers were the most likely among the five groups to ascribe negative traits to their native variety.

A 1992 study of code-switching by native Jeju speakers shows that Jeju was by then in an unfavorable diglossic relationship with Korean, and was largely restricted to informal contexts even between Jeju natives. Within a primarily Jeju conversation, Standard Korean was used to emphasize the rationality or truth value of statements. Switching to Jeju in a primarily Standard Korean conversation signified that the speaker was making a subjective statement or being less serious.

The same study notes that by 1992, even this variety restricted to the informal domain was usually a Korean dialect with a Jeju substratum, rather than the traditional Jeju language:

현재 상용되는 제주말의 경우, 표준말과의 차이가 과거에 비해 크게 줄어들고 있는 상황으로써 특히 어미활용에서 표준말과의 차이가 극대화되며, 다른 부분에서는 상대적으로 표준말과의 차이가 극소화된다는 점이다. 따라서 제주사람들은 과거 사용되던 토박이 말에 가까운 것은 '진한 (심한) 제주말'로, 현재 사용되는 제주말은 '옅은 제주말' 또는 '(표준어와) 섞어진 말'로 표현하는 등, 제주말과 표준말이 일종의 방언 연속체를 형성하는 것으로 인식하고 있다.

"As for the Jeju language [lit. 'Jeju speech'] in general use nowadays [as of 1992], the situation is that its differences from Standard Korean are greatly diminishing compared to the past. Its greatest differences with Standard Korean [now] lie especially in the suffix paradigm, and in other areas the differences are being minimized. The Jeju people accordingly understand that Jeju and Standard Korean are in a form of dialect continuum, and refer to the native language formerly in use as "thick (or intense) Jeju language" and the Jeju language currently in use as "light Jeju language" or "mixed (with Korean) language."

Current status and ongoing endangerment
Since 2010, UNESCO has classified Jeju as a critically endangered language, defined as one whose "youngest speakers are grandparents and older... [who] speak the language partially and infrequently." In 2018, the Endangered Languages Archive at SOAS University of London collected audio and video recordings of native Jeju speakers having everyday conversations, singing traditional songs, and performing rituals.

The official language of South Korea is Standard Korean. Nearly all residents of Jeju Island are bilingual in Standard Korean and Jeju, while many younger individuals are even more fluent in English than in Jeju. Standard Korean is most commonly used in the majority of public areas, while Jeju tends to be reserved for use at home and a few local markets. All schools located on Jeju Island are required to teach Standard Korean and only offer Jeju as an elective course. In addition, many Jeju Islander migrate to mainland Korea for a number of various reasons such as education, employment, and marriage contributing to decline of the Jejueo language. As a result, there are currently no monolingual speakers of Jeju.

The distinctive phonological, syntactic, and lexical features of the Jeju Island language, known as Jejueo or Jeju dialect, compared to Standard Korean, pose obstacles to effective communication. Phonological differences, such as variations in pitch accent and vowel distinctions, may lead to misunderstandings or difficulties in comprehension between Jeju natives and speakers of Standard Korean. Communication can also be made more difficult by syntactic variances, word order flexibility, and particle usage inconsistencies between Standard Korean and Jejueo. In contrast to the mainstream linguistic rules observed in mainland Korean, Jejueo maintains earlier grammatical structures and syntactic patterns that may lead to misunderstandings or confusion during conversations.

As of 2018, fluent speakers in Jeju Island were all over seventy years of age, while passive competence was found in some people in their forties and fifties. Younger Islanders speak Korean with Jeju substrate influence found in residual elements of the Jeju verbal paradigm and in select vocabulary such as kinship terms. The language is more vigorous in Osaka, where there may be fluent speakers born as late as the 1960s.

A 2008 survey of adult residents' knowledge of ninety Jeju cultural words showed that only twenty-one were understood by the majority of those surveyed. Lack of heritage knowledge of Jeju is even more severe among younger people. In 2010, 400 Jeju teenagers were surveyed for their knowledge of 120 basic Jeju vocabulary items, but only 19 words were recognized by the majority while 45 words were understood by less than 10%. A 2018 study suggests that even the verbal paradigm, among the more resilient parts of the substratum, may be in danger; the average middle schooler was more competent in the verb system of English, a language "taught only a few hours a week in school and in private tutoring institutions," than of Jeju.

Local attitudes towards Jeju
Historically, the Jeju language was seen as impolite or uncultured. Jeju uses fewer honorifics and has four levels of politeness, in comparison to the seven levels in Standard Korean. Because of the linguistic differences and cultural differences, Jeju Islanders were marginalized and excluded among mainland Koreans. In a 2011 Korea Times article, a student said they believed the language was not respectful enough to use with professors, and that the Seoul dialect was more sophisticated. In addition, Jeju is often associated with the countryside, as the majority of speakers tend to have traditional occupations, including farming, fishing, and diving. As a result, many younger children express a disinterest in learning the language.

Improving sentiment
However, recent surveys show improved sentiment towards the Jeju language. In a National Institute of the Korean Language survey in 2005, only 9.4% of Jeju Islanders were very proud of the regional variety. When the same survey was readministered in 2015, 36.8% were very proud of the language, and Jeju Islanders had become the most likely among South Korean dialect groups to have "very positive" opinions of the regional variety. In a 2017 study of 240 Jeju Islanders, 82.8% of those sampled considered Jeju to be "nice to listen to," and 74.9% hoped that their children would learn the language. But significant generational differences in attitudes were also observed. For instance, only 13.8% of Jeju Islanders between 20 and 40 much preferred Jeju over Standard Korean, while 49.1% of those above 80 did.

In a 2013 survey of Jeju natives, 77.9% agreed with the statement that "[the Jeju language] has to be passed down as part of Jeju culture." But a 2015 study of approximately 1,000 Jeju Islanders suggests that even though most Jeju Islanders believe the language to be an important part of the island's culture, the vast majority are skeptical of the language's long-term viability, and more people are unwilling than willing to actively participate in language preservation efforts.

Revitalization efforts

Revitalization efforts have been ongoing.

Government efforts
On 27 September 2007, the Jeju provincial government promulgated the Language Act for the Preservation and Promotion of the Jeju Language, which established five-year plans for state-backed language preservation. The Act encouraged public schools on Jeju Island to offer Jeju as an extracurricular activity, as well as to incorporate the language as a part of regular classes if relevant and feasible. In addition, multiple programs were provided for adults. For example, adult language programs are offered every year at the Jeju National University and are free of charge. There are also several local centres on Jeju Island that offer classes in Jeju Language specifically to marriage-based immigrants.

However, it was not until UNESCO's 2010 designation of Jeju as critically endangered that the provincial government became proactive in Jeju preservation efforts. In 2016, the provincial government allotted ₩685,000,000 (US$565,592 in 2016) to revitalization programs, and the government-funded Jeju Research Institute has compiled phrasebooks of the language. The provincial Ministry of Education has also published Jeju textbooks for elementary and secondary schools, although some textbooks really teach Standard Korean interspersed with Jeju lexical items. Some public schools offer after-school programs for Jeju, but the short duration of these classes may be insufficient to promote more than "symbolic" use by students. The linguistic competence of many teachers has also been challenged.

On 12 August 2011, the Research Centre for Jeju Studies was opened with the purpose of implementing projects for the revitalization and safeguarding of Jeju Language. The project encouraged the promotion of Jeju Language in schools by tasking the Education Bureau with several initiatives, including a training program for teachers. The project also started a radio broadcast in Jeju Language, as well as a radio campaign for Jeju slang and an annual Jeju Language festival. An iPhone application was developed, including a glossary, as well as a collection of proverbs, poems, and quizzes in Jeju Language. Finally, an introductory conversation brochure was distributed to both citizens and visitors of Jeju Island.

Popular media efforts
The Jeju Language Preservation Society, founded in December 2008, publishes a bimonthly Jeju-language magazine Deongdeureong-makke (덩드렁마께) and holds Jeju teaching programs and speaking contests. Children's books and a 2014 poetry anthology have also been published. Local bands and theater troupes have made Jeju-language performances. Regional newspapers such as the Jemin Ilbo and the Halla Ilbo include Jeju-language sections.

Local branches of KBS and MBC have launched Jeju radio programs and a television series. Recent South Korean media with nationwide appeal, including the 2010 television series Life is Beautiful and The Great Merchant, the 2012 drama film Jiseul, and the 2015 television series Warm and Cozy, have also featured spoken Jeju.

Cultural differences
In addition to the difference in language and dialect, Jeju Islanders and mainland Koreans share a number of cultural differences.

The historical isolation and unique identity of Jeju Island, which have nourished a strong sense of regional pride and unity among Jeju inhabitants, are two significant cultural differences. Jeju Island's distinct cultural traditions, folk beliefs, and practices set it apart from the Korean mainland are a result of the island's geographic isolation. For example, Jeju's traditional women divers, or haenyeo, represent the ideals of resiliency, collaboration, and environmental care and represent the island's matriarchal legacy and collective spirit.

Moreover, Jeju Island's tumultuous history, including the Jeju rebellion and subsequent mass killings, has left a profound impact on the collective memory and social identity of Jeju Islanders. The trauma and scars of historical events continue to resonate in the cultural consciousness, shaping perceptions, attitudes, and behaviors among Jeju natives. These experiences have contributed to a distinct sense of identity and solidarity among Jeju Islanders, often manifesting in cultural expressions, artistic forms, and community rituals that reflect resilience and resistance against oppression.

Religious practices on Jeju Island encompass a diverse range of beliefs, including shamanism, Buddhism, and Christianity, each contributing to the island's rich religious heritage and spiritual landscape. These religious traditions intersect with cultural rituals and festivals, such as the annual Jeju Fire Festival and Seongsan Sunrise Festival, which celebrate Jeju's natural beauty, cultural heritage, and community solidarity.

Orthography
Jeju has historically had no written language. Two recently devised standard orthographies are currently in use: a system created in 1991 by scholars of the Jeju Dialect Research Society, and a system promulgated by the provincial government in 2014. Both systems use the Korean alphabet Hangul with one additional letter ㆍ, which was used in the Middle and Early Modern Korean scripts but is now defunct in written Korean. Similar to the modern Korean script, Jeju orthographies have morphophonemic tendencies, meaning that transcribing the underlying morphology generally takes precedence over the surface form. The two orthographies differ largely because they are based on different morphological analyses of the language, especially of the verbal paradigm, as seen in the example below.

This article will use the government's orthography where the two differ.

Transliteration or romanization
The transliteration scheme generally used in Korean linguistics, including when transcribing Jeju, is the Yale Romanization system. Yang C., Yang S., and O'Grady 2019 instead uses a variant of the Revised Romanization system with the addition of the sequence aw for ㆍ.

This article also uses Revised Romanization with the addition of aw, but without Yang C., Yang S., and O'Grady 2019's one-to-one correspondence between Hangul glyphs and the Latin alphabet.

Consonants
The non-approximant consonants of Jeju correspond to the nineteen non-approximant consonants of Standard Korean, and Jeju displays the three-way contrast between stops and affricates characteristic of Modern Korean. Whether the voiced glottal fricative, absent in Standard Korean, exists as a phoneme in Jeju or merely as an allophone of remains disputed. A 2000 acoustic and aerodynamic study of eight native Jeju speakers concludes that "the consonants of the two languages seem to be the same in every respect... the phonetic realization of all [Jeju] consonants are the same as those found in [Seoul] Korean."

Consonantal phonological processes
Jeju allophony involves a number of phonological processes also found in Seoul Korean. As in Korean, surfaces as  intervocally. Also as in Korean, lax stops and affricates have fully voiced allophones in medial position, all obstruents have unreleased allophones in final position, and syllable-final sibilants surface as. Whether non-lax stops and affricates can appear in final position is controversial. The morphological analysis necessary for the government's orthography permits them, while the analysis behind the Jeju Language Research Society's orthography forbids them.

Most non-morphophonological consonant assimilation rules of Standard Korean are also found in Jeju. and are regularly palatalized to  before  or. Lax obstruents are tensed following another obstruent. aspirates both the preceding and the subsequent lax obstruent. A nasal consonant nasalizes a preceding obstruent or. becomes following all consonants except itself or, and this  can itself nasalize the preceding obstruent so that the underlying sequence  is realized as. On the other hand, underlying and  both produce.

Jeju also has consonant allophones that appear only at morpheme boundaries. Some of these are found in Standard Korean, such as the insertion of before  or  at most word-internal morpheme boundaries; the palatalization of  to  before an affixal ; and the tensing of obstruents following certain morpheme-final nasals. Other rules are absent in Standard Korean. For instance, a sonorant-final word or morpheme can trigger aspiration (for older speakers) or tensing (for younger speakers) in a subsequent lax consonant. In some cases this is due to an underlying consonant cluster, but not all cases can be explained in this way. Other Jeju-specific processes include the doubling of a word-final consonant when followed by a vowel, glide, or, and the lenition of  to  at some word boundaries.

Verbal conjugation can also lead to consonantal changes. Verb stem-final and  are lost before. In the case of verb stems ending in,. , and, the final consonants are always preserved in so-called regular verbs, but in irregular verbs, and  are lenited to  and  respectively while  and  are lost when followed by a vowel.

Underlying consonant clusters
While not permitted in the surface representation of Jeju, morpheme-final consonant clusters can exist in the underlying form. Many cases of post-sonorant aspiration involve morphemes whose Middle Korean cognates feature a final, suggesting that an underlying final after the sonorant should be posited in Jeju as well. Besides these -final clusters, Jeju permits a number of other final consonant clusters, including, , , , and (in the analysis of the government's orthography). These clusters surface as a single consonant in isolation or before a consonant, but are fully realized when followed by a vowel.

Vowels
Jeju traditionally has a nine-vowel system: the eight vowels of Korean with the addition of ㆍ, a Middle Korean phoneme lost in Seoul in the eighteenth century. The Jeju-do dialect is known to exhibit more conservative vowel sounds preserving older vowel distinctions, compared to standard Korean.

The phonemic identity of ㆍ is controversial, but native speakers most commonly realize the phoneme as. and are only distinguished in the initial syllable.

Among younger and less fluent speakers, and  have both raised to  and  or  respectively, resulting in a seven-vowel system identical to the vowel inventory of Seoul Korean. The raising of Jeju occurred before the raising of, and may have predated Standard Korean's ongoing merger of  and. The subsequent loss of may have been motivated by a language-internal desire for symmetry in the vowel system. On the other hand, the vowel mergers are accelerated among Jeju speakers living in coastal communities more exposed to Standard Korean.

Jeju has two or three glides:, , and possibly. can occur with all vowels except and. and have merged even among speakers who distinguish the monophthongs, and many speakers who retain  also merge  with. cannot occur with the three back vowels or with. occurs only with, and the resulting diphthong is generally realized as  word-initially and  otherwise.

Glide-vowel sequences may be analyzed as diphthongs, with the phonemic identities of, , and being , , and  respectively.

Vowel phonological processes
Several phonological processes affect the surface realization of Jeju vowels. In one process shared with Standard Korean, a bisyllabic vowel sequence may be contracted to a monosyllabic polyphthong.

Vowel-affecting processes are particularly numerous in the verbal paradigm. Verb stem-final is lost before a vowel-initial suffix. Similar to Standard Korean, a stem-final diphthongizes a subsequent vowel by inserting the onglide. Unlike in its sister language, Jeju insertion may occur even with an intervening consonant, and between a verb stem ending in, , or and a suffix with initial.

Many of Jeju's consonant-initial verbal suffixes take an initial epenthetic vowel if the previous morpheme ends with a consonant. The default epenthetic vowel is -으-, but the vowel surfaces as -이-   following a sibilant and as -우-   following an underlying labial.

Like Standard Korean but unlike Middle Korean, Koreanic vowel harmony is no longer generally applicable in all native morphemes but remains productive in sound symbolism and certain verbal suffixes. Jeju has two harmonic classes, yin and yang. The neutral vowel can occur with either class.

For instance, the perfective aspect marker -엇 takes the vowel harmonic allomorph -앗  after verb stems whose (final) vowel is yang:

In certain cases, suffix allomorphs do not match the harmonic class of the previous vowel. Verb stems with final vowel or  take the yang allomorph if their Middle Korean forms were, thus conserving their original harmonic class while violating their current one. Disyllabic stems that end in also take the yang allomorph, but monosyllabic  stems or disyllabic  stems do not.

Phonotactics
Jeju syllable structure is (C)(G)V(C) with G being a glide.

As in Standard Korean,  cannot occur syllable-initially, and   does not occur word-initially in native words.

Prosody
Jeju does not have phonemic vowel length, stress, or tone. Its phonological hierarchy is characterized by accentual phrases similar to those of Standard Korean, with a basic Low-High-Low-High tonal pattern varying according to sentence type, but there are also important differences in the two languages' prosody. Jeju has a weaker tonal distinction within the first half of the accentual phrase than Seoul Korean does, while its aspirate consonants do not produce as significant a high pitch as their Seoul equivalents. Jeju uses more contour tones, where the pitch shifts within a single syllable, than Seoul Korean. Unlike in Seoul Korean, older and fluent speakers of Jeju will also lengthen the final vowel of both clauses in alternative questions.

Grammar
 ORD: ordinal numeral INTR: interrogative MED: medial demonstrative SE: sentence ender CE: canonical ending REP : reportive NPST: nonpast

Jeju is typologically similar to Korean, both being head-final agglutinative languages. However, the two languages show significant differences in the verbal paradigm, such as Jeju's use of a dedicated conditional suffix.

Nouns
Jeju nouns may be a single morpheme, a compound of multiple nouns, or a base noun with a merged attributive verb, or form through derivational affixes attached to nouns or verb stems. In compound nouns that include a native morpheme, the phoneme -s- may intervene between the two elements. Because this "in-between " appears only after a vowel and before a consonant, it is never realized as but almost always surfaces as.

 * Single-morpheme noun: 쉐 "cattle"
 * Noun compound:

 * Noun compound with :

 * Noun with merged attributive verb:

 * Noun derived from noun through affix:

 * Noun derived from verb through affix:

 * Verbal noun:

(Examples from Yang C., Yang S, and O'Grady 2019 and Ko J. 2011a)

Some Jeju nouns are bound nouns, meaning that they cannot appear independently without a noun phrase. The example below features the bound noun 침 "worth" accompanied by the obligatory attributive verb.

Jeju has two suffixing plural markers, which are obligatory for plural nouns accompanied by determiners and optional otherwise. The plural marker -덜 can occur with all nouns and pronouns. The marker -네 is restricted for humans and pronouns, and can also have an associative meaning: e.g. 만수네  "Mansu and his family" (lit. 'Mansu and his associates'). The combined sequence -네덜 is sometimes also used.

Nouns accompanied by numerals usually take a variety of classifiers, such as 재 for counting trees and 곡지  for counting songs. Classifiers for cardinals are unmarked, but those for ordinals are followed by the ordinal-marking 체.

Noun particles
Jeju marks noun case and other semantic relations through suffixing noun particles. Particles that mark the nominative, accusative, and genitive cases are very frequently omitted. The table below is not exhaustive and lists only some of the most significant particles.

Verbs
The Jeju verb consists of a root that is followed by suffixes that provide grammatical information such as voice, tense, aspect, mood, evidentiality, relative social status, and the formality of the utterance. Jeju verbs include not only action verbs familiar to English speakers such as 먹다 "to eat" or 베리다  "to see," but also adjectival verbs such as 버치다  "to be heavy" or 훍다  "to be thick." Verbs can take derivational suffixes to form adverbs and nouns.

 * ᄇᆞ디- "to be close" →  ᄇᆞ디게  "closely"
 * 궂- "to be bad" →  궂임  "badness"
 * 입- "to wear" →  입기  "wearing"

Especially for wh-questions and exclamations, Jeju speakers commonly use a verbal noun in place of a verb inflected for tense-aspect-mood.

Verbs may also be given an attributive meaning through one of four adnominal suffixes.

 * Adnominal suffix 은 : Past event for action verbs, achieved state for adjectival verbs

 * Adnominal suffix 단 : Habitual action in the past

 * Adnominal suffix (으)는 : Nonpast/present event or state, commonly habitual; cannot occur with other suffixes and must combine directly with the bare verb stem; can occur with adjectival verbs, unlike in Korean

 * Adnominal suffix 을 : Future/conjectural event or state

Pre-final suffixes
Jeju has a number of pre-final verbal suffixes: tense-aspect-mood markers which follow the verb stem but cannot appear at the end of the inflected verb. The exact number of these suffixes is unclear because scholars disagree on the correct morphological segmentation. One analysis of the suffix paradigm, as presented in Yang C., Yang S., and O'Grady 2019, is given below.

There is relatively widespread agreement on the existence of the following four discrete TAM morphemes, presented in the order they co-occur: the continuative aspect marker 어ᇝ, the perfective aspect marker 엇 , the prospective mood marker 읔 , and the realis mood marker (으)느. Depending on the analysis of the aforementioned epenthetical vowels that precede many verbal suffixes, the base forms of the three morphemes may alternately be analyzed as 엄시, 어시 , 크 , and 느.

is an imperfective or continuative aspect particle, referring to a process perceived as ongoing and similar to the English construction "be VERB-ing." With an adjectival verb, it has an inchoative ("beginning to; become") meaning. A verb with is interpreted as either present or future by default, and some analyses interpret the particle as also conveying the present tense for specific events and states. The suffix has a vowel-harmonic variant, as well as allomorphs , , and when following certain vowels.

Often characterized as a perfective aspect marker, has also been described as a present perfect marker and as behaving as a perfective marker with some verbs and as a past tense marker with others. can express non-past events in certain constructions that call for verbs "conceptualized in their entirety," such as a hypothetical future event. In adjectival verbs, it may also refer to a current state that contrasts with a past situation. can also be doubled for a habitual or a past perfect interpretation. Also like, this suffix takes the vowel-harmonic variant and has allomorphs , , and  after certain vowels.

The prospective mood marker 읔/으크 marks the subject's intention in first-person-subject declarative sentences or second-person-subject interrogative sentences, and the speaker's conjecture otherwise. may also have a future-tense interpretation.

can only be followed by a small number of suffixes in Yang C., Yang S., and O'Grady 2019's analysis. Some analyses treat the initial vowel of the following suffix as part of an allomorph or nuanced variant of, so that 가커라 "[I] will go" may be segmented as  or.

The realis or indicative mood marker (으)느 indicates "a fact or habitual action in the nonpast" which the speaker perceives to be true in general, permanently, or over a longer duration of time, as demonstrated in the contrast below. The putative non-past-tense marker may also be analyzed as an allomorph of. In this context, the morpheme has also been interpreted as a perfect marker (not to be confused with the perfective marker).

The existence of the Korean subject-honorific marker (으)시 is controversial for Jeju, with some scholars arguing that it was entirely absent and others that it was restricted to higher registers. Ko J. 2011b notes that it was used only "by officials while referring to people of very high status and by the seonbi of the educated classes."

Segmenting verb-final suffixes
The segmentation of verb-final elements is controversial. The two recent extensive treatments of the topic, Yang C., Yang S., and O'Grady 2019 and Kim Jee-hong 2015, give incompatible analyses of the suffix paradigm.

Yang C., Yang S., and O'Grady 2019 includes a slot for tense in the Jeju verb, with three dedicated markers.

 * Non-past tense: 은
 * Past tense: 언, with vowel-harmonic allomorph 안
 * Future tense: 을

They further divide verb-final suffixes into three categories: Type 1, which cannot occur with tense markers; Type 2, which must occur with either a tense marker or the aspect marker, which loses its underlying before a Type 2 suffix; and a mixed type, which can occur with the non-past marker but not with the other two tense markers. The vast majority of suffixes are categorized as Tense 1 and thus cannot follow a tense marker. Uniquely among pre-final suffixes, the past tense marker can also appear without a final suffix.

Examples of Yang C., Yang S., and O'Grady 2019's segmentation are given below.

In Kim Jee-hong's analysis, verb-final single morphemes are termed "canonical endings." Canonical endings are contrasted with a wide variety of "non-canonical endings," formed by the fusion of various grammatical elements such as multiple canonical endings, truncated conjunctive and embedded sentences, and bound nouns connected to the verb stem or a canonical ending via an attributive or a nominalizer. The most common canonical component of these non-canonical endings is the suffix 어 (vowel-harmonic allomorph 아 ), which Kim calls the unmarked "default ending."

Since Yang C., Yang S., and O'Grady 2019's tenses align with the aforementioned attributive suffixes, sentences they analyze as "Tense-Type 2 Suffix" sequences are often analyzed as non-canonical endings with a "Canonical ending-Attributive-Bound noun" composition by Kim Jee-hong. Many of Yang C., Yang S., and O'Grady 2019's Type 1 suffixes are also interpreted as polymorphemic non-canonical endings. Kim Jee-hong also segments some of Yang C., Yang S., and O'Grady 2019's mixed-type suffixes so that the base form of the suffix includes the of the latter's non-past tense marker.

Examples from Kim Jee-hong 2015's analysis, directly corresponding to the examples above of Yang C., Yang S., and O'Grady 2019, are given below. The "default ender" is bolded.

Sentence enders
Jeju has a number of clause-final suffixes, called "sentence enders" in Yang C., Yang S., and O'Grady 2019 and "terminal suffixes" in Korean, that provide information such as degree of formality, social status, evidentality, and modality. Sentence enders may consist of one or multiple morphemes. Kim Jee-hong argues for four speech levels in Jeju, defined by the degree of formality and deference their sentence enders connote: informal and plain (non-honorific); formal and plain; informal and honorific, marked by the morpheme 우, and formal and honorific, featuring the morpheme 읍. An archaic speech level showing extreme deference is attested from shamanic chants.

As different segmentation hypotheses produce different sentence enders. the chart below will list only a small, illustrative sample of the dozens of suffixes that appear in Yang C., Yang S., and O'Grady 2019 and Kim Jee-h. 2015. The classification is based on Kim Jee-hong 2017, which differs from Kim Jee-hong 2015.

The honorific verbs, which show deference to the addressee, are formed by a special suffix that can be followed only by a small number of sentence enders.

The informal honorific forms are marked by 우 or (으)우. The former is used with the copula verb 이다 and with all inflected verbs, and the latter is used with uninflected adjectival verbs. and may take the alternative form 수  after a verb inflected for aspect and a non-liquid consonant, respectively. The informal honorific form cannot occur with uninflected action verbs. The two suffixes may only be followed by the sentence enders in the table below. Informal honorific requests cannot be formed morphologically.

The formal honorific forms involve the honorific marker 읍 followed by one or two morphemes. Only the six following formal honorific forms are possible.

Connectives
Jeju uses an array of verb-final connective suffixes to link clauses within sentences, much as English does with conjunctions such as and, or, that, but, and because.

Some Jeju connectives, such as the suffixes 언/엉 "and", occur in pairs with one variant ending in  and the other in. Hong Chong-rim and Song Sang-jo both note that the choice between and  is often determined by the inflections of the subsequent clause; certain pre-final suffixes and sentence enders require a -connective in the previous clause, while others require a -connective. Hong suggests that is used for specific and objective events and states, while  implies a general and subjective event or state. Song argues that is used for completed or achieved verbs, and  for incomplete or unachieved verbs. The nuances below are thus possible.

The distinction between and  does not exist in mainland Korean varieties. Yang C., Yang S., and O'Grady 2019 reports that "the contrast between and  appears to be disappearing, and the distinctions that remain are subtle and variable."

An important class of connectives, used for reporting speech and thoughts, is formed by the suffix 엔/엥, which fuses with sentence enders as in the example of below.

Similarly, informal honorific conjectural becomes 켄 ; plain forms  and  become 젠 ; question enders  and  become 겐  and 곤 ; honorific imperative  becomes 읍센 ; and so forth. These fused suffixes may be used for both quotative and reportive purposes. In Standard Korean, indirect speech is strictly distinguished from the quotative by the removal of addressee honorifics and the switching of pronouns. In Jeju, the lines between direct and indirect speech are more blurred. All four forms below—given in order of increasing indirectness—are in use, and have the same meaning, "He said [to a superior] that he was going home."

Other connectives include (으)민 "if"; (으)난  "because"; and 단/당  "after".

Auxiliary and light verbs
Jeju has many auxiliary verbs that are linked to the preceding main verb by the morpheme 어/아. These include 안네다 "to give," for an action that benefits a superior; 불다  "to throw away," for an action yielding a complete result; and 지다  "to become," for a change of state. is also used to indicate ability.

Jeju also uses light verbs, which have little semantic meaning but combine with nouns to form verbs. The most common light verb is ᄒᆞ다 "to do," e.g. 부름씨  "errand" → 부름씨ᄒᆞ다  "to run an errand". There is also a large inventory of periphrastic phrases that convey modality.

Post-phrasal particles
Jeju has a small group of particles that commonly occur at the very end of phrases or sentences, many of which play important roles as discourse markers. The four principal ones are the formality marker 마씀 and the emphatic markers 게, 이 , and 양.

(variants 마씸, 마씨 ) may occur after subsentential phrases such as a bare or case-inflected noun, or attach to a small number of mostly plain sentence enders. The particle shows the speaker's deference towards the addressee, but is considered more emotionally intimate than the verbally inflected honorifics. In certain contexts, may be used with an intention to snub the addressee.

is a discourse marker that attaches to adverbs, nouns and noun particles, and both sentence enders and connectives. It adds emphasis to the utterance and is often used to agree with or confirm something the addressee has just said. is used similarly to, but is weaker in its emphasis. Both cannot be used while addressing a social superior, and also cannot appear in formal speech. Both particles can also appear in isolation: as a strong affirmation to a question,  as an indication that the speaker has not heard or does not believe what has been said.

shows deference, but is considered more informal than. At the end of a sentence, it emphasizes the speaker's beliefs or attitudes. For example, a question becomes a rhetorical one when is attached: 이시카  "Could there be?" → 이시카양 "How could there be?" The particle is also commonly used for sarcastic mock deference, such as by parents while scolding children. Sentence-initially or internally, the suffix may establish the preceding element as the topic of discourse. is also used in isolation as an interjection to get the attention of unfamiliar individuals, such as a shopkeeper, or to request the addressee to repeat what they have just said.

In the example below from Yang C. 2009, three of the four particles discussed above are used.

Note the granddaughter's use of the verbally inflected honorific and the deference-marking  and  while addressing the grandmother.

Pronouns and deixis
Jeju has the following basic personal pronouns.

According to Yang C., Yang S., and O'Grady 2019, there are four basic deictic demonstratives in Jeju. Most other sources mention three, which are identical to those of Standard Korean.

 * Proximal: 이 "this"
 * Medial or absent: 그 "that"
 * Distal: 저 "that"

Vocabulary
Most of the Jeju lexicon is Koreanic, and "a sizeable number" of words are identical with Korean. There are false friends between the languages, such as Korean 감다 "to wash hair" and Jeju ᄀᆞᆷ다  "to wash the body." Jeju also preserves many Middle Korean terms now lost in Korean, such as 갓 "wife; woman" and 어시  "parent." Like Korean, Jeju uses many Sino-Korean words based on local readings of Classical Chinese.

Jeju Island was ruled by the Mongols in the late thirteenth century and some Middle Mongol terms still survive in the language, though the extent of Mongol influence is disputed. Popular claims of hundreds of Mongol loans in Jeju are linguistically unsound. Uncontroversial Mongol loans are most common in terms relating to animal husbandry.

Jeju may have loans from an ancient Japonic substratum. As the last fluent generation of Jeju speakers were born under or shortly after Japanese rule, remaining speakers also use many loans from Modern Japanese.

Sound symbolism
Jeju has widespread sound symbolism in ideophones. The use of sound symbolism to form emphatic variants of words is more common in Jeju than in Seoul Korean.

Jeju sound symbolism operates with both consonants and vowels. The intensity of a Jeju word may be strengthened by using tense and especially aspirate obstruents. The sound symbolism may also be emphasized through the addition of consonants, by adding the sequence -락 to both reduplicated segments, and with fortition or lenition. The yang harmonic class of vowels has a bright, small connotation, and the yin vowel class gives a dark, large connotation. Ko Jae-hwan also gives examples of three or four layers of vowel sound symbolism.

 * Consonant sound symbolism:
 * 고시롱 "savory" → 꼬시롱  "[very] savory" → 코시롱  "[extremely] savory"
 * 을강을강 "[small] sound of rat gnawing teeth" → 글강글강  "[large] sound of rat gnawing teeth"
 * ᄇᆞᆯ착ᄇᆞᆯ착 "easily angered" → ᄇᆞᆯ치락ᄇᆞᆯ치락  "[very] easily angered"
 * 크뜽크뜽 "neatly aligned" → 코찡코찡  "[very] neatly aligned"
 * Vowel sound symbolism:
 * 동골동골 "round [of a small object]" → 둥굴둥굴  "round [of a large object]"
 * ᄋᆞᆼ당ᄋᆞᆼ당 "[small and light] sound of muttered complaints" → 옹당옹당  "[large and heavy] sound of muttered complaints" → 웅당웅당  "[very large and very heavy] sound of muttered complaints"
 * ᄆᆞᆫ들ᄆᆞᆫ들 "smooth to the touch [of a very small or dry object]" → 맨들맨들  "smooth to the touch [of a somewhat small or dry object]" → 문들문들  "slippery to the touch [of a somewhat large or wet object]" → 민들민들  "slippery to the touch [of a very large or wet object]"

Multiple sound-symbolic strategies may combine in a single word. Kang S. 2008 gives eight sound symbolic variants of the ideophone ᄆᆞᆯ탁ᄆᆞᆯ탁 "the shape of many objects being blunt," each more intense than the other:

ᄆᆞᆯ탁ᄆᆞᆯ탁 → ᄆᆞᆯ트락ᄆᆞᆯ트락  → ᄆᆞᆯ착ᄆᆞᆯ착  → ᄆᆞᆯ치락ᄆᆞᆯ치락  → 뫁탁몰탁  →  몰착몰착  → 몰트락몰트락  → 몰치락몰치락

Kinship terminology
The kinship terminology of Jeju has been the focus of particular attention. Jeju has a complex kinship system that distinguishes the gender of both the speaker and the relative. Gender distinctions are particularly noticeable in sibling terminology. The words 성 and 아시  refer to "older same-gender sibling" and "younger same-gender sibling" respectively, while 오라방  and 누이  refer specifically to "brother of a female" and "sister of a male" respectively. Female speakers also tend to refer to relatives with native compounds, whereas male speakers prefer Sino-Korean terms. For instance, the same cousin may be referred to by a man as ᄉᆞ춘 "cousin" but by a woman as 고모님 ᄄᆞᆯ  "paternal aunt's daughter." A major distinction between Jeju and Korean kinship terms is that women do not use honorifics to refer to their in-laws, reflecting weaker historical influence from Confucian patriarchal norms.

Jeju also uses supplementary prefixes to clarify the type of kinship, equivalent to "step-" or "maternal" in English. These include 친-, 성- , and 당- for paternal relations, 웨-  for maternal relations, 다슴-  for step-relations, 처-  and 가시-  for a male's in-laws, and 시-  for a woman's in-laws. Five other prefixes, which may be combined, mark relative age: 쳇- or 큰-  "eldest," 셋-  "second eldest of three or more," 말젯-  "third eldest of four or more," and 족은-  "youngest." These are used to distinguish relatives of the same generation.

 * 하르방 "grandfather"
 * 큰하르방 "oldest brother of one's grandfather"
 * 셋하르방 "second brother of one's grandfather"
 * 큰말젯하르방 "third brother of one's grandfather"
 * 셋말젯하르방 "fourth brother of one's grandfather"
 * 족은말젯하르방 "fifth brother of one's grandfather"
 * 족은하르방 "youngest brother of one's grandfather"

Other prefixes include 왕-, used in 왕하르방 "great-grandfather", and 넛- , used to refer to a sibling of one's grandparent generally.

Sample text
The following is an excerpt from a version of the Menggam bon-puri, one of the epic chants recited by Jeju shamans. In this myth, the poacher Song Saman discovers an abandoned skull in the hills and cares for it as if it were his own ancestor. The skull reciprocates by warning Song Saman of his early death and advising him on how to avoid the chasa, the three gods of death.

This version was transcribed between 1956 and 1963 from the recitation of the shaman Byeon Sin-saeng, born c. 1904. The transcription predates both standardized orthographies of Jeju. The transcriber openly notes that the orthography is inconsistent. No attempt was made in this article to standardize or update the orthography.

title: Jeju language


text:
Chronometry

Chronometry or horology (lit. 'the study of time') is the science studying the measurement of time and timekeeping. Chronometry enables the establishment of standard measurements of time, which have applications in a broad range of social and scientific areas. Horology usually refers specifically to the study of mechanical timekeeping devices, while chronometry is broader in scope, also including biological behaviours with respect to time (biochronometry), as well as the dating of geological material (geochronometry).

Horology is commonly used specifically with reference to the mechanical instruments created to keep time: clocks, watches, clockwork, sundials, hourglasses, clepsydras, timers, time recorders, marine chronometers, and atomic clocks are all examples of instruments used to measure time. People interested in horology are called horologists. That term is used both by people who deal professionally with timekeeping apparatuses, as well as enthusiasts and scholars of horology. Horology and horologists have numerous organizations, both professional associations and more scholarly societies. The largest horological membership organisation globally is the NAWCC, the National Association of Watch and Clock Collectors, which is US based, but also has local chapters elsewhere.

Records of timekeeping are attested during the Paleolithic, in the form of inscriptions made to mark the passing of lunar cycles and measure years. Written calendars were then invented, followed by mechanical devices. The highest levels of precision are presently achieved by atomic clocks, which are used to track the international standard second.

Etymology
Chronometry is derived from two root words, chronos and metron (χρόνος and μέτρον in Ancient Greek respectively), with rough meanings of "time" and "measure". The combination of the two is taken to mean time measuring.

In the Ancient Greek lexicon, meanings and translations differ depending on the source. Chronos, used in relation to time when in definite periods, and linked to dates in time, chronological accuracy, and sometimes in rare cases, refers to a delay. The length of the time it refers ranges from seconds to seasons of the year to lifetimes, it can also concern periods of time wherein some specific event takes place, or persists, or is delayed. The root word is correlated with the god Chronos in Ancient Greek mythology, who embodied the image of time, originated from out of the primordial chaos. Known as the one who spins the Zodiac Wheel, further evidence of his connection to the progression of time. However, Ancient Greek makes a distinction between two types of time, chronos, the static and continuing progress of present to future, time in a sequential and chronological sense. And Kairos, a concept based in a more abstract sense, representing the opportune moment for action or change to occur.

Kairos (καιρός) carries little emphasis on precise chronology, instead being used as a time specifically fit for something, or also a period of time characterised by some aspect of crisis, also relating to the endtime. It can as well be seen in the light of an advantage, profit, or fruit of a thing, but has also been represented in apocalyptic feeling, and likewise shown as variable between misfortune and success, being likened to a body part vulnerable due to a gap in armor for Homer, benefit or calamity depending on the perspective. It is also referenced in Christian theology, being used as implication of God's action and judgement in circumstances.

Because of the inherent relation between chronos and kairos, their function the Ancient Greek's portrayal and concept of time, understanding one means understanding the other in part. The implication of chronos, an indifferent disposition and eternal essence lies at the core of the science of chronometry, bias is avoided, and definite measurement is favoured.

Biochronometry
Biochronometry (also chronobiology or biological chronometry) is the study of biological behaviours and patterns seen in animals with factors based in time. It can be categorised into Circadian rhythms and Circannual cycles. Examples of these behaviours can be: the relation of daily and seasonal tidal cues to the activity of marine plants and animals, the photosynthetic capacity and phototactic responsiveness in algae, or metabolic temperature compensation in bacteria.

Circadian rhythms of various species can be observed through their gross motor function throughout the course of a day. These patterns are more apparent with the day further categorised into activity and rest times. Investigation into a species is conducted through comparisons of free-running and entrained rhythms, where the former is attained from within the species' natural environment and the latter from a subject that has been taught certain behaviours. Circannual rhythms are alike but pertain to patterns within the scale of a year, patterns like migration, moulting, reproduction, and body weight are common examples, research and investigation are achieved with similar methods to circadian patterns.

Circadian and circannual rhythms can be seen in all organisms, in both single and multi-celled organisms. A sub-branch of biochronometry is microbiochronometry (also chronomicrobiology or microbiological chronometry), and is the examination of behavioural sequences and cycles within micro-organisms. Adapting to circadian and circannual rhythms is an essential evolution for living organisms, these studies, as well as educating on the adaptations of organisms also bring to light certain factors affecting many of species' and organisms' responses, and can also be applied to further understand the overall physiology, this can be for humans as well, examples include: factors of human performance, sleep, metabolism, and disease development, which are all connected to biochronometrical cycles.

Mental chronometry
Mental chronometry (also called cognitive chronometry) studies human information processing mechanisms, namely reaction time and perception. As well as a field of chronometry, it also forms a part of cognitive psychology and its contemporary human information processing approach. Research comprises applications of the chronometric paradigms – many of which are related to classical reaction time paradigms from psychophysiology – through measuring reaction times of subjects with varied methods, and contribute to studies in cognition and action. Reaction time models and the process of expressing the temporostructural organisation of human processing mechanisms have an innate computational essence to them. It has been argued that because of this, conceptual frameworks of cognitive psychology cannot be integrated in their typical fashions.

One common method is the use of event-related potentials (ERPs) in stimulus-response experiments. These are fluctuations of generated transient voltages in neural tissues that occur in response to a stimulus event either immediately before or after. This testing emphasises the mental events' time-course and nature and assists in determining the structural functions in human information processing.

Geochronometry
The dating of geological materials makes up the field of geochronometry, and falls within areas of geochronology and stratigraphy, while differing itself from chronostratigraphy. The geochronometric scale is periodic, its units working in powers of 1000, and is based in units of duration, contrasting with the chronostratigraphic scale. The distinctions between the two scales have caused some confusion – even among academic communities.

Geochronometry deals with calculating a precise date of rock sediments and other geological events, giving an idea as to what the history of various areas is, for example, volcanic and magmatic movements and occurrences can be easily recognised, as well as marine deposits, which can be indicators for marine events and even global environmental changes. This dating can be done in a number of ways. All dependable methods – barring the exceptions of thermoluminescence, radioluminescence and ESR (electron spin resonance) dating – are based in radioactive decay, focusing on the degradation of the radioactive parent nuclide and the corresponding daughter product's growth. By measuring the daughter isotopes in a specific sample its age can be calculated. The preserved conformity of parent and daughter nuclides provides the basis for the radioactive dating of geochronometry, applying the Rutherford Soddy Law of Radioactivity, specifically using the concept of radioactive transformation in the growth of the daughter nuclide.

Thermoluminescence is an extremely useful concept to apply, being used in a diverse amount of areas in science, dating using thermoluminescence is a cheap and convenient method for geochronometry. Thermoluminescence is the production of light from a heated insulator and semi-conductor, it is occasionally confused with incandescent light emissions of a material, a different process despite the many similarities. However, this only occurs if the material has had previous exposure to and absorption of energy from radiation. Importantly, the light emissions of thermoluminescence cannot be repeated. The entire process, from the material's exposure to radiation would have to be repeated to generate another thermoluminescence emission. The age of a material can be determined by measuring the amount of light given off during the heating process, by means of a phototube, as the emission is proportional to the dose of radiation the material absorbed.

Time metrology
Time metrology or time and frequency metrology is the application of metrology for timekeeping, including frequency stability. Its main tasks are the realization of the second as the SI unit of measurement for time and the establishment of time standards and frequency standards as well as their dissemination.

History
Early humans would have used their basic senses to perceive the time of day, and relied on their biological sense of time to discern the seasons in order to act accordingly. Their physiological and behavioural seasonal cycles mainly being influenced by a melatonin based photoperiod time measurement biological system – which measures the change in daylight within the annual cycle, giving a sense of the time in the year – and their circannual rhythms, providing an anticipation of environmental events months beforehand to increase chances of survival.

There is debate over when the earliest use of lunar calendars was, and over whether some findings constituted as a lunar calendar. Most related findings and materials from the palaeolithic era are fashioned from bones and stone, with various markings from tools. These markings are thought to not have been the result of marks to represent the lunar cycles but non-notational and irregular engravings, a pattern of latter subsidiary marks that disregard the previous design is indicative of the markings being the use of motifs and ritual marking instead.

However, as humans' focus turned to farming the importance and reliance on understanding the rhythms and cycle of the seasons grew, and the unreliability of lunar phases became problematic. An early human accustomed to the phases of the moon would use them as a rule of thumb, and the potential for weather to interfere with reading the cycle further degraded the reliability. The length of a moon is on average less than our current month, not acting as a dependable alternate, so as years progress the room of error between would grow until some other indicator would give indication. The Ancient Egyptian calendars were among the first calendars made, and the civil calendar even endured for a long period afterwards, surviving past even its culture's collapse and through the early Christian era. It has been assumed to have been invented near 4231 BC by some, but accurate and exact dating is difficult in its era and the invention has been attributed to 3200 BC, when the first historical king of Egypt, Menes, united Upper and Lower Egypt. It was originally based on cycles and phases of the moon, however, Egyptians later realised the calendar was flawed upon noticing the star Sirius rose before sunrise every 365 days, a year as we know it now, and was remade to consist of twelve months of thirty days, with five epagomenal days. The former is referred to as the Ancient Egyptians' lunar calendar, and the latter the civil calendar.

Early calendars often hold an element of their respective culture's traditions and values, for example, the five day intercalary month of the Ancient Egyptian's civil calendar representing the birthdays of the gods Horus, Isis, Set, Osiris and Nephthys. Maya use of a zero date as well as the Tzolkʼin's connection to their thirteen layers of heaven (the product of it and all the human digits, twenty, making the 260-day year of the year) and the length of time between conception and birth in pregnancy.

Europe
There are many horology museums and several specialized libraries devoted to the subject. One example is the Royal Greenwich Observatory, which is also the source of the Prime Meridian and the home of the first marine timekeepers accurate enough to determine longitude (made by John Harrison). Other horological museums in the London area include the Clockmakers' Museum, which re-opened at the Science Museum in October 2015, the horological collections at the British Museum, the Science Museum (London), and the Wallace Collection. The Guildhall Library in London contains an extensive public collection on horology. In Upton, also in the United Kingdom, at the headquarters of the British Horological Institute, there is the Museum of Timekeeping. A more specialised museum of horology in the United Kingdom is the Cuckooland Museum in Cheshire, which hosts the world's largest collection of antique cuckoo clocks.

One of the more comprehensive museums dedicated to horology is the Musée international d'horlogerie, in La Chaux-de-Fonds in Switzerland, which contains a public library of horology. The Musée d'Horlogerie du Locle is smaller but located nearby. Other good horological libraries providing public access are at the Musée international d'horlogerie in Switzerland, at La Chaux-de-Fonds, and at Le Locle.

In France, Besançon has the Musée du Temps (Museum of Time) in the historic Palais Grenvelle. In Serpa and Évora, in Portugal, there is the Museu do Relógio. In Germany, there is the Deutsches Uhrenmuseum in Furtwangen im Schwarzwald, in the Black Forest, which contains a public library of horology.

North America
The two leading specialised horological museums in North America are the National Watch and Clock Museum in Columbia, Pennsylvania, and the American Clock and Watch Museum in Bristol, Connecticut. Another museum dedicated to clocks is the Willard House and Clock Museum in Grafton, Massachusetts. One of the most comprehensive horological libraries open to the public is the National Watch and Clock Library in Columbia, Pennsylvania.

Organizations
Notable scholarly horological organizations include:
 * American Watchmakers-Clockmakers Institute – AWCI (United States of America)
 * Antiquarian Horological Society – AHS (United Kingdom)
 * British Horological Institute – BHI (United Kingdom)
 * Chronometrophilia (Switzerland)
 * Deutsche Gesellschaft für Chronometrie – DGC (Germany)
 * Horological Society of New York – HSNY (United States of America)
 * National Association of Watch and Clock Collectors – NAWCC (United States of America)
 * UK Horology - UK Clock & Watch Company based in Bristol

title: Chronometry


text:
National Highway System (United States)

The National Highway System (NHS) is a network of strategic highways within the United States, including the Interstate Highway System and other roads serving major airports, ports, military bases, rail or truck terminals, railway stations, pipeline terminals and other strategic transport facilities. Altogether, it constitutes the largest highway system in the world.

Individual states are encouraged to focus federal funds on improving the efficiency and safety of this network. The roads within the system were identified by the United States Department of Transportation (USDOT) in cooperation with the states, local officials, and metropolitan planning organizations (MPOs) and approved by the United States Congress in 1995.

Legislation
The Intermodal Surface Transportation Efficiency Act (ISTEA) in 1991 established certain key routes such as the Interstate Highway System, be included. The act provided a framework to develop a National Intermodal Transportation System which "consists of all forms of transportation in a unified, interconnected manner, including the transportation systems of the future, to reduce energy consumption and air pollution while promoting economic development and supporting the Nation's preeminent position in international commerce".

The National Highway System Designation Act of 1995 (,, COMPS-1425) is a United States Act of Congress that was signed into law by President Bill Clinton on November 28, 1995. The legislation designated about 160,955 mi of roads, including the Interstate Highway System, as the NHS.

Aside from designating the system, the act served several other purposes, including restoring $5.4 billion in funding to state highway departments, giving Congress the power to prioritize highway system projects, repealing all federal speed limit controls, and prohibits the federal government from requiring states to use federal-aid highway funds to convert existing signs or purchase new signs with metric units.

The act also created a State Infrastructure Bank pilot program. Ten states were chosen in 1996 for this new method of road financing. These banks would lend money like regular banks, with funding coming from the federal government or the private sector, and they would be repaid through such means as highway tolls or taxes. In 1997, 28 more states asked to be part of the program. Ohio was the first state to use a state infrastructure bank to start building a road. An advantage of this method was completing projects faster; state laws and the lack of appropriate projects were potential problems.

Overview
According to the Federal Highway Administration, the 160000 mi National Highway System includes roads important to the United States' economy, defense, and mobility, from one or more of the following road networks (specific routes may be part of more than one sub-system):

 * Interstate Highway System: The entire Interstate Highway System (which is also known as the Dwight D. Eisenhower National System of Interstate and Defense Highways) is included in the NHS, but retains its separate identity within the NHS.
 * Other Principal Arterials: Highways in rural and urban areas which provide access between an arterial and a major port, airport, public transportation facility, or other intermodal transportation facility. (Facilities accessed include 207 airports, 198 ports, 190 rail or truck terminals, 67 Amtrak railway stations, 58 pipeline terminals as well as 82 intercity bus terminals, 307 public transit stations, 37 ferry terminals, and 20 multi-purpose passenger terminals.)
 * Strategic Highway Network (STRAHNET): The entire network of highways which are important to the United States’ strategic defense policy and which provide defense access, continuity, and emergency capabilities for defense purposes.
 * Major Strategic Highway Network Connectors: Highways which provide access between major military installations and routes which are part of STRAHNET.
 * Intermodal Connectors: Routes which provide access between major intermodal facilities and the other four subsystems making up the NHS.

The system includes 4% of the nation's roads, but carries more than 40% of all highway traffic, 75% of heavy truck traffic, and 90% of tourist traffic. All urban areas with a population of over 50,000 and about 90% of America's population live within 5 mi of the network, which is the longest in the world.

title: National Highway System (United States)