text:
Dagome iudex

Dagome iudex is one of the earliest historical documents relating to Poland. Although Poland is not mentioned by name, it refers to Dagome and Ote (Mieszko I and his wife, Oda von Haldensleben) and their sons in 991, placing their land (called "Civitas Schinesghe") under the protection of the Apostolic See. The document's name derives from its opening words.

History
The Dagome iudex survives in the form of a summary, completed c. 1080. It was found in a register compiled by a curial cardinal during the papacy of Gregory VII.

Most historians believe that the word "Dagome" is a melding of two names: the Christian "Dago", for "Dagobert" (Mieszko's hypothetical baptismal name), and the "Me," for pagan "Mieszko." The Latin word iudex ("judge") could refer to "prince." Another interpretation is that "Dagome iudex" is a corruption of "Ego Mesco dux" ("I, Prince Mieszko"). In the Vatican copy, the e of Dagome might have an s adscriptum (similar to cedilla), although the Vatican copyist read iudex literally, relating it to Sardinia and its four "judges".

Place names are misspelled by the writer who made the summary. He was apparently unaware that the document related to territory later called Poland.

The boundaries of the "Gniezno" state are described as those that extended to the "Long Sea" (the Baltic), Prussia, Rus', Kraków, Moravia and the Oder River. Lesser Poland is included by the mention of its capital, Kraków ("craccoa"). Between alemura, probably Olomouc and Upper Lusatia region of the Milceni (terra mileze) a straightened border could include Silesia.

The text seems to use civitas schinesghe as a synonym of Greater Poland. Otherwise, the boundary description would be more logical if schenisghe meant the city of Szczecin. Of the other regions and places in Mieszko's territory, it mentioned only Kraków and Lusatia, both without fines (border). The regions outside Mieszko's rule, pruzze (Prussia) and russe (Ruthenia) were mentioned with the word fines.

The Dagome iudex is of critical importance to Polish history, since it provided a general description of the future Polish state in that period. It, however, left many questions unanswered. First, it did not explain why Mieszko I placed his state under the Pope's protection. Also, it is unclear why the document did not mention Mieszko's eldest son, Bolesław I the Brave. Instead, his sons by his second wife (except the third), Oda, were mentioned instead. Finally, Mieszko I is not referred to as "Dagome" in any other document.

Historians suppose that Bolesław's absence from the document might be explained by an old custom whereby children received their inheritance as soon as they reached the age of majority. Thus, Bolesław the Brave might have received Kraków as his part of his father's legacy before the Dagome iudex was written.

Text of the Dagome iudex

 * In Latin:

 * Item in alio tomo sub Iohanne XV papa Dagome iudex et Ote senatrix et filii eorum: Misicam et Lambertus - nescio cuius gentis homines, puto autem Sardos fuisse, quoniam ipsi a IIII iudicibus reguntur - leguntur beato Petro contulisse unam civitatem in integro, que vocatur Schinesghe, cum omnibus suis pertinentiis infra hos affines, sicuti incipit a primo latere longum mare, fine Bruzze usque in locum, qui dicitur Russe et fines Russe extendente usque in Craccoa et ab ipsa Craccoa usque ad flumen Oddere recte in locum, qui dicitur Alemure, et ab ipsa Alemura usque in terram Milze recte intra Oddere et exinde ducente iuxta flumen Oddera usque in predictam civitatem Schinesghe.

 * In English translation:

 * "Also in another volume from the times of Pope John XV, Dagome, lord, and Ote, lady, and their sons Misico and Lambert (I do not know of which nation those people are, but I think they are Sardinians, for those are ruled by four judges) were supposed to give to Saint Peter one state in whole which is called Schinesghe, with all its lands in borders which run along the long sea, along Prussia to the place called Rus, thence to Kraków and from said Kraków to the River Oder, straight to a place called Alemure, and from said Alemure to the land of Milczanie, and from the borders of that people to the Oder and from that, going along the River Oder, ending at the earlier mentioned city of Schinesghe."

title: Dagome iudex


text:
DA

Da, DA, dA, DÄ and other variants may refer to:

Arts, entertainment, and media

 * DA! (band), a Chicago post-punk band of the 1980s
 * Da (play), a 1978 play by Hugh Leonard
 * Da (film), a 1988 film based on the play
 * Damon Amendolara, American sports talk radio host
 * Daniel Amos, also known as D.A. and Dä, an American Christian rock band
 * Dennis Armand Lucchesi, who recorded the song "Ready 'n' Steady" under the name "D.A."
 * Destination America, television channel
 * DeviantArt or DA, a website that focuses on art
 * Dumbledore's Army, a group formed by Harry Potter in his 5th year to teach students defensive spells
 * Jon Moxley, formerly Dean Ambrose in WWE, a wrestler

Degrees and licenses

 * Diploma of Anesthesiology, a degree conferred by some medical institutions such as the Royal College of Anaesthetists
 * Doctor of Arts, an academic degree

Organizations

 * Da!, a Russian youth movement
 * Debtors Anonymous
 * Air Georgia, a Georgian airline (IATA code DA)

Politics and judiciary

 * Da (political party), a defunct Israeli political party
 * Defence Advisory Notice, a government demand in Australia and the UK not to publish or broadcast a specified news item
 * Democratic Alliance (South Africa), a South African political party
 * Democratic Awakening, East German political party
 * Department of Agriculture (Philippines), an executive department
 * Deutsche Alternative ("German Alternative"), a rightist group
 * District attorney, (United States) chief prosecutor for a local government area, particularly a county
 * Dreptate şi Adevăr a defunct alliance of parties in Romania

Places

 * Da County, a division in Sichuan, China
 * DA postcode area, a postcode area in England
 * Da River or Black River, a river in China and northwestern Vietnam
 * Dah, Ivory Coast, a village in Montagnes District, Ivory Coast, also spelt "Da"

Biology and medicine

 * DA (chemotherapy), standard-dose cytarabine plus daunorubicin
 * Deoxyanthocyanidin
 * Domoic acid, a neurotoxin produced by phytoplankton
 * Donor-Acceptor
 * Dopamine, a monoamine neurotransmitter

Other uses in science and technology

 * Dalton (unit) (symbol Da), also called the unified atomic mass unit
 * Deca- or da-, an SI prefix for a factor of 10
 * Distribution amplifier, a device that accepts a single input signal and provides this same signal to multiple isolated outputs
 * Double-action, a firearm operation mechanism in which the trigger both cocks and releases the hammer
 * NZR DA class, a New Zealand diesel locomotive
 * SJ Da, a Swedish electric locomotive
 * Domain authority Domain Authority

Sports

 * U.S. Soccer Development Academy, former United States soccer league

Other uses

 * D.A. Wallach (born 1985), American musician and business executive
 * Da (Javanese), a syllable in Javanese script
 * Da. or Dòna, the honorific Mrs. in Occitan language
 * Da Hoss, an American racehorse
 * Dame of St Andrew, a discontinued award within the Order of Barbados
 * Danish language (ISO 639-1 alpha-2 code DA)
 * Dearness allowance, cost of living allowance to government employees in Bangladesh, India, and Pakistan
 * Desk accessory, graphical programs
 * Direct action (military), in special operations
 * Disadvantage, an off-case argument used by the Negative team in a policy debate
 * Doomsday argument, a probabilistic argument based on demographics predicting how many people will be born
 * Duck's ass or duck's arse, a haircut; particularly popular during the 1950s
 * Dynamic game difficulty balancing, also known as difficulty adjustment or DA, an algorithm in video games.

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

title: DA


text:
Derek Walcott

Sir Derek Alton Walcott  OM  (23 January 1930 – 17 March 2017) was a Saint Lucian poet and playwright. He received the 1992 Nobel Prize in Literature. His works include the Homeric epic poem Omeros (1990), which many critics view "as Walcott's major achievement." In addition to winning the Nobel Prize, Walcott received many literary awards over the course of his career, including an Obie Award in 1971 for his play Dream on Monkey Mountain, a MacArthur Foundation "genius" award, a Royal Society of Literature Award, the Queen's Medal for Poetry, the inaugural OCM Bocas Prize for Caribbean Literature, the 2010 T. S. Eliot Prize for his book of poetry White Egrets and the Griffin Trust For Excellence in Poetry Lifetime Recognition Award in 2015.

Early life and childhood
Walcott was born and raised in Castries, Saint Lucia, in the West Indies, the son of Alix (Maarlin) and Warwick Walcott. He had a twin brother, the playwright Roderick Walcott, and a sister, Pamela Walcott. His family is of English, Dutch and African descent, reflecting the complex colonial history of the island that he explores in his poetry. His mother, a teacher, loved the arts and often recited poetry around the house. His father was a civil servant and a talented painter. He died when Walcott and his brother were one year old, and were left to be raised by their mother. Walcott was brought up in Methodist schools. His mother, who was a teacher at a Methodist elementary school, provided her children with an environment where their talents could be nurtured. Walcott's family was part of a minority Methodist community, who felt overshadowed by the dominant Catholic culture of the island established during French colonial rule.

As a young man Walcott trained as a painter, mentored by Harold Simmons, whose life as a professional artist provided an inspiring example for him. Walcott greatly admired Cézanne and Giorgione and sought to learn from them. Walcott's painting was later exhibited at the Anita Shapolsky Gallery in New York City, along with the art of other writers, in a 2007 exhibition named The Writer's Brush: Paintings and Drawing by Writers.

He studied as a writer, becoming "an elated, exuberant poet madly in love with English" and strongly influenced by modernist poets such as T. S. Eliot and Ezra Pound. Walcott had an early sense of a vocation as a writer. In the poem "Midsummer" (1984), he wrote:

Forty years gone, in my island childhood, I felt that the gift of poetry had made me one of the chosen, that all experience was kindling to the fire of the Muse.

At 14, Walcott published his first poem, a Miltonic, religious poem, in the newspaper The Voice of St Lucia. An English Catholic priest condemned the Methodist-inspired poem as blasphemous in a response printed in the newspaper. By 19, Walcott had self-published his first two collections with the aid of his mother, who paid for the printing: 25 Poems (1948) and Epitaph for the Young: XII Cantos (1949). He sold copies to his friends and covered the costs. He later commented:

"I went to my mother and said, 'I'd like to publish a book of poems, and I think it's going to cost me two hundred dollars.' She was just a seamstress and a schoolteacher, and I remember her being very upset because she wanted to do it. Somehow she got it—a lot of money for a woman to have found on her salary. She gave it to me, and I sent off to Trinidad and had the book printed. When the books came back I would sell them to friends. I made the money back."

The influential Bajan poet Frank Collymore critically supported Walcott's early work.

After attending high school at Saint Mary's College, he received a scholarship to study at the University College of the West Indies in Kingston, Jamaica.

Career
After graduation, Walcott moved to Trinidad in 1953, where he became a critic, teacher and journalist. He founded the Trinidad Theatre Workshop in 1959 and remained active with its board of directors.

Exploring the Caribbean and its history in a colonialist and post-colonialist context, his collection In a Green Night: Poems 1948–1960 (1962) attracted international attention. His play Dream on Monkey Mountain (1970) was produced on NBC-TV in the United States the year it was published. Makak is the protagonist in this play; and "Makak"s condition represents the condition of the colonized natives under the oppressive forces of the powerful colonizers". In 1971 it was produced by the Negro Ensemble Company off-Broadway in New York City; it won an Obie Award that year for "Best Foreign Play". The following year, Walcott won an OBE from the British government for his work.

He was hired as a teacher by Boston University in the United States, where he founded the Boston Playwrights' Theatre in 1981. That year he also received a MacArthur Foundation Fellowship in the United States. Walcott taught literature and writing at Boston University for more than two decades, publishing new books of poetry and plays on a regular basis. Walcott retired from his position at Boston University in 2007. He became friends with other poets, including the Russian expatriate Joseph Brodsky, who lived and worked in the U.S. after being exiled in the 1970s, and the Irishman Seamus Heaney, who also taught in Boston.

Walcott's epic poem Omeros (1990), which loosely echoes and refers to characters from the Iliad, has been critically praised as his "major achievement." The book received praise from publications such as The Washington Post and The New York Times Book Review, which chose Omeros as one of its "Best Books of 1990".

Walcott was awarded the Nobel Prize in Literature in 1992, the second Caribbean writer to receive the honour after Saint-John Perse, who was born in Guadeloupe, received the award in 1960. The Nobel committee described Walcott's work as "a poetic oeuvre of great luminosity, sustained by a historical vision, the outcome of a multicultural commitment". He won an Anisfield-Wolf Book Award for Lifetime Achievement in 2004.

His later poetry collections include Tiepolo's Hound (2000), illustrated with copies of his watercolours; The Prodigal (2004), and White Egrets (2010), which received the T. S. Eliot Prize and the 2011 OCM Bocas Prize for Caribbean Literature.

Derek Walcott held the Elias Ghanem Chair in Creative Writing at the University of Nevada, Las Vegas in 2007. In 2008, Walcott gave the first Cola Debrot Lectures In 2009, Walcott began a three-year distinguished scholar-in-residence position at the University of Alberta. In 2010, he became Professor of Poetry at the University of Essex.

As a part of St Lucia's Independence Day celebrations, in February 2016, he became one of the first knights of the Order of Saint Lucia.

Themes
Methodism and spirituality have played a significant role from the beginning in Walcott's work. He commented: "I have never separated the writing of poetry from prayer. I have grown up believing it is a vocation, a religious vocation." Describing his writing process, he wrote: "the body feels it is melting into what it has seen… the 'I' not being important. That is the ecstasy... Ultimately, it's what Yeats says: 'Such a sweetness flows into the breast that we laugh at everything and everything we look upon is blessed.' That's always there. It's a benediction, a transference. It's gratitude, really. The more of that a poet keeps, the more genuine his nature." He also notes: "if one thinks a poem is coming on... you do make a retreat, a withdrawal into some kind of silence that cuts out everything around you. What you're taking on is really not a renewal of your identity but actually a renewal of your anonymity."

Influences
Walcott said that his writing was influenced by the work of the American poets Robert Lowell and Elizabeth Bishop, who were also friends.

Playwriting
He published more than twenty plays, the majority of which have been produced by the Trinidad Theatre Workshop and have also been widely staged elsewhere. Many of them address, either directly or indirectly, the liminal status of the West Indies in the post-colonial period. Through poetry he also explores the paradoxes and complexities of this legacy.

Essays
In his 1970 essay "What the Twilight Says: An Overture", discussing art and theatre in his native region (from Dream on Monkey Mountain and Other Plays), Walcott reflects on the West Indies as a colonized space. He discusses the problems for an artist of a region with little in the way of truly Indigenous forms, and with little national or nationalist identity. He states: "We are all strangers here... Our bodies think in one language and move in another". The epistemological effects of colonization inform plays such as Ti-Jean and his Brothers. Mi-Jean, one of the eponymous brothers, is shown to have much information but truly knows nothing. Every line Mi-Jean recites is rote knowledge gained from the coloniser; he is unable to synthesize it or apply it to his life as a colonised person.

Walcott notes of growing up in West Indian culture:

"What we were deprived of was also our privilege. There was a great joy in making a world that so far, up to then, had been undefined... My generation of West Indian writers has felt such a powerful elation at having the privilege of writing about places and people for the first time and, simultaneously, having behind them the tradition of knowing how well it can be done—by a Defoe, a Dickens, a Richardson."

Walcott identified as "absolutely a Caribbean writer", a pioneer, helping to make sense of the legacy of deep colonial damage. In such poems as "The Castaway" (1965) and in the play Pantomime (1978), he uses the metaphors of shipwreck and Crusoe to describe the culture and what is required of artists after colonialism and slavery: both the freedom and the challenge to begin again, salvage the best of other cultures and make something new. These images recur in later work as well. He writes: "If we continue to sulk and say, Look at what the slave-owner did, and so forth, we will never mature. While we sit moping or writing morose poems and novels that glorify a non-existent past, then time passes us by."

Omeros
Walcott's epic book-length poem Omeros was published in 1990 to critical acclaim. The poem very loosely echoes and references Homer and some of his major characters from The Iliad. Some of the poem's major characters include the island fishermen Achille and Hector, the retired English officer Major Plunkett and his wife Maud, the housemaid Helen, the blind man Seven Seas (who symbolically represents Homer), and the author himself.

Although the main narrative of the poem takes place on the island of St. Lucia, where Walcott was born and raised, Walcott also includes scenes from Brookline, Massachusetts (where Walcott was living and teaching at the time of the poem's composition), and the character Achille imagines a voyage from Africa onto a slave ship that is headed for the Americas; also, in Book Five of the poem, Walcott narrates some of his travel experiences in a variety of cities around the world, including Lisbon, London, Dublin, Rome, and Toronto. Composed in a variation on terza rima, the work explores the themes that run throughout Walcott's oeuvre: the beauty of the islands, the colonial burden, the fragmentation of Caribbean identity, and the role of the poet in a post-colonial world.

In this epic, Walcott speaks in favour of unique Caribbean cultures and traditions to challenge the modernity that existed as a consequence of colonialism.

Criticism and praise
Walcott's work has received praise from major poets including Robert Graves, who wrote that Walcott "handles English with a closer understanding of its inner magic than most, if not any, of his contemporaries", and Joseph Brodsky, who praised Walcott's work, writing: "For almost forty years his throbbing and relentless lines kept arriving in the English language like tidal waves, coagulating into an archipelago of poems without which the map of modern literature would effectively match wallpaper. He gives us more than himself or 'a world'; he gives us a sense of infinity embodied in the language." Walcott noted that he, Brodsky, and the Irish poet Seamus Heaney, who all taught in the United States, were a band of poets "outside the American experience".

The poetry critic William Logan critiqued Walcott's work in a New York Times book review of Walcott's Selected Poems. While he praised Walcott's writing in Sea Grapes and The Arkansas Testament, Logan had mostly negative things to say about Walcott's poetry, calling Omeros "clumsy" and Another Life "pretentious". Logan concluded with: "No living poet has written verse more delicately rendered or distinguished than Walcott, though few individual poems seem destined to be remembered."

Most reviews of Walcott's work are more positive. For instance, in The New Yorker review of The Poetry of Derek Walcott, Adam Kirsch had high praise for Walcott's oeuvre, describing his style in the following manner:

"By combining the grammar of vision with the freedom of metaphor, Walcott produces a beautiful style that is also a philosophical style. People perceive the world on dual channels, Walcott's verse suggests, through the senses and through the mind, and each is constantly seeping into the other. The result is a state of perpetual magical thinking, a kind of Alice in Wonderland world where concepts have bodies and landscapes are always liable to get up and start talking."

Kirsch calls Another Life Walcott's "first major peak" and analyzes the painterly qualities of Walcott's imagery from his earliest work through to later books such as Tiepolo's Hound. Kirsch also explores the post-colonial politics in Walcott's work, calling him "the postcolonial writer par excellence". Kirsch calls the early poem "A Far Cry from Africa" a turning point in Walcott's development as a poet. Like Logan, Kirsch is critical of Omeros, which he believes Walcott fails to successfully sustain over its entirety. Although Omeros is the volume of Walcott's that usually receives the most critical praise, Kirsch believes Midsummer to be his best book.

In 2013 Dutch filmmaker Ida Does released Poetry is an Island, a feature documentary film about Walcott's life and the ever-present influence of his birthplace of St Lucia.

Personal life
In 1954 Walcott married Fay Moston, a secretary, and they had a son, the St. Lucian painter Peter Walcott. The marriage ended in divorce in 1959. Walcott married a second time to Margaret Maillard in 1962, who worked as an almoner in a hospital. Together they had two daughters, Elizabeth Walcott-Hackshaw and Anna Walcott-Hardy, before divorcing in 1976. In 1976, Walcott married for a third time, to actress Norline Metivier; they divorced in 1993. His companion until his death was Sigrid Nama, a former art gallery owner.

Walcott was also known for his passion for travelling to countries around the world. He split his time between New York, Boston, and St. Lucia, and incorporated the influences of different locations into his pieces of work.

Allegations of sexual harassment
In 1982, a Harvard sophomore accused Walcott of sexual harassment in September 1981. She alleged that after she refused a sexual advance from him, she was given the only C in the class. In 1996 a student at Boston University sued Walcott for sexual harassment and "offensive sexual physical contact". The two reached a settlement.

In 2009, Walcott was a leading candidate for the position of Oxford Professor of Poetry. He withdrew his candidacy after reports of the accusations against him of sexual harassment from 1981 and 1996.

When the media learned that pages from an American book on the topic were sent anonymously to a number of Oxford academics, this aroused their interest in the university's decisions. Ruth Padel, also a leading candidate, was elected to the post. Within days, The Daily Telegraph reported that she had alerted journalists to the harassment cases. Under severe media and academic pressure, Padel resigned. Padel was the first woman to be elected to the Oxford post, and some journalists attributed the criticism of her to misogyny and a gender war at Oxford. They said that a male poet would not have been so criticized, as she had reported published information, not rumour.

Numerous respected poets, including Seamus Heaney and Al Alvarez, published a letter of support for Walcott in The Times Literary Supplement, and criticized the press furore. Other commentators suggested that both poets were casualties of the media interest in an internal university affair because the story "had everything, from sex claims to allegations of character assassination". Simon Armitage and other poets expressed regret at Padel's resignation.

Death
Walcott died at his home in Cap Estate, St. Lucia, on 17 March 2017. He was 87. He was given a state funeral on Saturday, 25 March, with a service at the Cathedral Basilica of the Immaculate Conception in Castries and burial at Morne Fortune.

Legacy
In 1993, a public square and park located in central Castries, Saint Lucia, was named Derek Walcott Square. A documentary film, Poetry Is an Island: Derek Walcott, by filmmaker Ida Does, was produced to honour him and his legacy in 2013.

The Saint Lucia National Trust acquired Walcott's childhood home at 17 Chaussée Road, Castries, in November 2015, renovating it before opening it to the public as Walcott House in January 2016.

In 2019, Arrowsmith Press, in partnership with The Derek Walcott Festival in Port-of-Spain, Trinidad, and the Boston Playwrights' Theatre, began awarding the annual Derek Walcott Prize for Poetry to a full-length book of poems by a living poet who is not a US citizen published in the previous calendar year.

In January 2020, the Sir Arthur Lewis Community College in St. Lucia announced that Walcott's books on Caribbean Literature and poetry have been donated to its Library.

Awards and honours

 * 1969: Cholmondeley Award
 * 1971: Obie Award for Best Foreign Play (for Dream on Monkey Mountain)
 * 1972: Officer of the Order of the British Empire
 * 1981: MacArthur Foundation Fellowship ("genius award")
 * 1988: Queen's Gold Medal for Poetry
 * 1990: Arts Council of Wales International Writers Prize
 * 1990: W. H. Smith Literary Award (for poetry Omeros)
 * 1992: Nobel Prize in Literature
 * 2004: Anisfield-Wolf Book Award for Lifetime Achievement
 * 2008: Honorary doctorate from the University of Essex
 * 2011: T. S. Eliot Prize (for poetry collection White Egrets)
 * 2011: OCM Bocas Prize for Caribbean Literature (for White Egrets)
 * 2015: Griffin Trust For Excellence in Poetry Lifetime Recognition Award
 * 2016: Knight Commander of the Order of Saint Lucia

Poetry collections

 * 1948: 25 Poems
 * 1949: Epitaph for the Young: Xll Cantos
 * 1951: Poems
 * 1962: In a Green Night: Poems 1948—60
 * 1964: Selected Poems
 * 1965: The Castaway and Other Poems
 * 1969: The Gulf and Other Poems
 * 1973: Another Life
 * 1976: Sea Grapes
 * 1979: The Star-Apple Kingdom
 * 1981: Selected Poetry
 * 1981: The Fortunate Traveller
 * 1983: The Caribbean Poetry of Derek Walcott and the Art of Romare Bearden
 * 1984: Midsummer
 * 1986: Collected Poems, 1948–1984, featuring "Love After Love"
 * 1987: The Arkansas Testament
 * 1990: Omeros
 * 1997: The Bounty
 * 2000: Tiepolo's Hound, includes Walcott's watercolors
 * 2004: The Prodigal
 * 2007: Selected Poems (edited, selected, and with an introduction by Edward Baugh)
 * 2010: White Egrets
 * 2014: The Poetry of Derek Walcott 1948–2013
 * 2016: Morning, Paramin (illustrated by Peter Doig)

Plays

 * 1950: Henri Christophe: A Chronicle in Seven Scenes
 * 1952: Harry Dernier: A Play for Radio Production
 * 1953: Wine of the Country
 * 1954: The Sea at Dauphin: A Play in One Act
 * 1957: Ione
 * 1958: Drums and Colours: An Epic Drama
 * 1958: Ti-Jean and His Brothers
 * 1966: Malcochon: or, Six in the Rain
 * 1967: Dream on Monkey Mountain
 * 1970: In a Fine Castle
 * 1974: The Joker of Seville
 * 1974: The Charlatan
 * 1976: O Babylon!
 * 1977: Remembrance
 * 1978: Pantomime
 * 1980: The Joker of Seville and O Babylon!: Two Plays
 * 1982: The Isle Is Full of Noises
 * 1984: The Haitian Earth
 * 1986: Three Plays: The Last Carnival, Beef, No Chicken, and A Branch of the Blue Nile
 * 1991: Steel
 * 1993: Odyssey: A Stage Version
 * 1997: The Capeman (book and lyrics, both in collaboration with Paul Simon)
 * 2002: Walker and The Ghost Dance
 * 2011: Moon-Child
 * 2014: O Starry Starry Night

Other books

 * 1990: The Poet in the Theatre, Poetry Book Society (London)
 * 1993: The Antilles: Fragments of Epic Memory (New York: Farrar, Straus & Giroux)
 * 1996: Conversations with Derek Walcott, (Jackson, MS: University of Mississippi)
 * 1996: (With Joseph Brodsky and Seamus Heaney) Homage to Robert Frost (New York: Farrar, Straus & Giroux)
 * 1998: What the Twilight Says (essays), (New York: Farrar, Straus & Giroux)
 * 2002: Walker and Ghost Dance (New York: Farrar, Straus & Giroux)
 * 2004: Another Life: Fully Annotated, Boulder, CO: Lynne Rienner Publishers

title: Derek Walcott


text:
Decipherment

In philology, decipherment is the discovery of the meaning of texts written in ancient or obscure languages or scripts.

Ancient languages
In a few cases, a multilingual artifact has been necessary to facilitate decipherment, the Rosetta Stone being the classic example. Statistical techniques provide another pathway to decipherment, as does the analysis of modern languages derived from ancient languages in which undeciphered texts are written. Archaeological and historical information is helpful in verifying hypothesized decipherments.

Deciphered scripts

 * Cuneiform
 * Egyptian hieroglyphs
 * Kharoshthi
 * Linear B
 * Mayan
 * Staveless Runes
 * Cypriot Syllabary

Undeciphered scripts

 * Rongorongo (Decipherment of rongorongo)
 * Indus script
 * Cretan hieroglyphs
 * Byblos syllabary
 * Linear A
 * Linear Elamite
 * Cypro-Minoan syllabary
 * Espanca
 * Numidian language

Undeciphered texts

 * Phaistos Disc
 * Rohonc Codex
 * Voynich Manuscript

title: Decipherment


text:
Talk:Decipherment

From the article:

 * (Decipherment) Is usually considered the second step in comprehension after cryptanalysis

That's odd, because as I understand it some degree of comprehension is usually needed in cryptanalysis, as otherwise a false decrypt is hard to discern from plaintext - can you explain? -- The Anome

-- Hmm, let me think about it..

VERY good question.

little guru

I don't think the dead sea scrolls count under 'decipherment'. Conservation, transcription, translation, yes, but there were no particular problems reading the texts, since they were all in well-known script. --MichaelTinkler

-- I have removed this definition (see text below) from the article, as it appears to be a personal concept, as opposed to a concept that is in general use: (a Google search for "philosophy decipherment" finds pages about the main sense, not this). Could any expert in philosophy correct me (giving a reference) if I'm wrong? -- The Anome

 * Decipherment is the Cryptanalysis of documents, events, lab experiments, body language etc. that a philosopher undertakes to get as close as possible to truth.

 * Is usually considered the second step in comprehension after cryptanalysis

 * Because of the fact that the epistemologist doesn't know if the reality that he is examining could be considered truth at first approach, he starts what is called scientific experimentation.

-- The word decipherment is according to the dictionaries I have access to, just a synonym for "decoding". The article now deals almost exclusively with philological decipherment of unknown scripts/languages. Isn't that a bit like having an article about the "Oceans of the world" and spending the entire article talking about the Atlantic?? I know that Wikipedia isn't supposed to "define common words", but shouldn't the article at least give some form of mention of the fact that the word often means something else? --Gabbe 12:30 Jan 8, 2003 (UTC)
 * I think I would agree with most of this. As I use the words, we have decypher=decrypt (if the underlying obscuration is a cypher), decode=decrypt (if underlying is a code), and cryptanalysis the process of doing decryption. Decypherment=an act of decyphering, and so on. The dictionary cited would seem to have missed a trick. The spelling difference between cy and ci has been a bit of a TT here on WP (see WikiProject Crytography at discussion/cypher vs cipher for extended coverage). ww 15:19, 10 Aug 2004 (UTC)
 * I vote for moving relevant (most) parts of this article to one entitled "Paleographic decipherment", or something along those lines. Simply "decipherment/decypherment" is far too ambiguous. —Gabbe 11:46, Dec 19, 2004 (UTC)
 * Perhaps, although we could keep it here, and simply have a disambiguation header at the top of the page saying something like "This article is about the analysis of documents in unknown languages; see cryptanalysis for a discussion of breaking secret codes and ciphers."? — Matt Crypto 00:45, 20 Dec 2004 (UTC)

Decipher, Inc.
This page is clearly not a disambiguation article, so where should a link to Decipher, Inc. go? --IanWatson 23:44, 22 October 2006 (UTC)

statistics
http://www.google.com/search?q=cache:7jmYpJoTv3EJ:www.bluhorizonlines.org/icon/icon6.html+decipherment+-wikipedia+mathemathical+theory&hl=en&ct=clnk&cd=1&gl=us —The preceding unsigned comment was added by Nasz (talk • contribs) 11:18, 9 February 2007 (UTC).

link to orphan
Wow, this page doesn't get much traffic.

Anyway, I linked the orphan Combinatorial method (linguistics) here. Not advocating it, but it could probably use some fresh air. kwami (talk) 05:48, 4 August 2009 (UTC)

Moving text here that relates to other topics - this is not a disambiguation page
Onceinawhile (talk) 14:22, 22 December 2023 (UTC)

title: Talk:Decipherment


text:
Decca Navigator System

The Decca Navigator System was a hyperbolic radio navigation system that allowed ships and aircraft to determine their position by using radio signals from a dedicated system of static radio transmitters. The system used phase comparison of two low frequency signals between 70 and 129 kHz, as opposed to pulse timing systems like Gee and LORAN. This made it much easier to design receivers using 1940s electronics, and operation was simplified by giving a direct readout of Decca coordinates without the complexity of a cathode ray tube and highly skilled operator.

The system was invented and developed by Decca in the UK. It was first deployed by the Royal Navy during World War II for the vital task of clearing the minefields to enable the D-Day landings. The Allied forces needed an accurate system not known to the Germans and thus free of jamming. After the war, it came off the secret list and was commercially developed by the Decca Company and deployed around UK and later used in many areas around the world. At its peak there were about 180 transmitting stations using "chains" of three or four transmitters each to allow position fixing by plotting intersecting electronic lines. Decca's primary use was for ship navigation in coastal waters, offering much better accuracy than the competing LORAN system. Fishing vessels were major post-war users, but it was also used on some aircraft, including a very early (1949) application of moving map displays. The system was deployed extensively in the North Sea and was used by helicopters operating to oil platforms.

The opening of the more accurate Loran-C system to civilian use in 1974 offered stiff competition, but Decca was well established by this time and continued operations to 2000. Decca Navigator was eventually replaced, along with Loran and similar systems, by the GPS in 2000, when that became available for public use.

Overview

The Decca Navigator System consisted of individual groups of land-based radio transmitters organised into chains of three or four stations. Each chain consisted of a master station and three (occasionally two) secondary stations, termed Red, Green and Purple. Ideally, the secondaries would be positioned at the vertices of an equilateral triangle with the master at the centre. The baseline length, that is, the master-secondary distance, was typically 60-120 nmi.

Each station transmitted a continuous wave signal that, by comparing the phase difference of the signals from the master and one of the secondaries, produced a relative phase measure that was presented on a clock-like display. The phase difference was caused by the relative distance between the stations as seen by the receiver. As the receiver moves these distances change and those changes are represented by the movement of the hands on the displays.

If one selects a particular phase difference, say 30 degrees, and plots all the locations where that phase difference occurs, the result is a set of hyperbolic lines of position called a pattern. As there were three secondaries there were three patterns, also termed Red, Green and Purple. The patterns were drawn on nautical charts as a set of hyperbolic lines in the appropriate colour.

Receivers determined their location by measuring the phase difference from two or more of the patterns from the displays. They could then look at the chart to find where the two closest charted hyperbolas crossed. The accuracy of this measurement was improved by choosing the set of two patterns that resulted in the lines crossing at as close to a right angle as possible.

Detailed principles of operation
When two stations transmit at the phase-locked frequency, the difference in phase between the two signals is constant along a hyperbolic path. If two stations transmit on the same frequency, it is impossible for the receiver to separate them. Instead, each chain was allocated a nominal frequency, known as 1f, and each station in the chain transmitted at a harmonic of this base frequency, as follows:

The frequencies given are those for Chain 5B, known as the English Chain, but all chains used similar frequencies between 70 kHz and 129 kHz.

Decca receivers multiplied the signals received from the Master and each Slave by different values to arrive at a common frequency (least common multiple, LCM) for each Master/Slave pair, as follows:

It was phase comparison at this common frequency that resulted in the hyperbolic lines of position. The interval between two adjacent hyperbolas on which the signals are in phase was called a lane. Since the wavelength of the common frequency was small compared with the distance between the Master and Slave stations there were many possible lines of position for a given phase difference, and so a unique position could not be arrived at by this method.

Other receivers, typically for aeronautical applications, divided the transmitted frequencies down to the basic frequency (1f) for phase comparison, rather than multiplying them up to the LCM frequency.

Lanes and zones
Early Decca receivers were fitted with three rotating Decometers that indicated the phase difference for each pattern. Each Decometer drove a second indicator that counted the number of lanes traversed – each 360 degrees of phase difference was one lane traversed. In this way, assuming the point of departure was known, a more or less distinct location could be identified.

The lanes were grouped into zones, with 18 green, 24 red, or 30 purple lanes in each zone. This meant that on the baseline (the straight line between the Master and its Slave) the zone width was the same for all three patterns of a given chain. Typical lane and zone widths on the baseline are shown in the table below (for chain 5B):

The lanes were numbered 0 to 23 for red, 30 to 47 for green and 50 to 79 for purple. The zones were labelled A to J, repeating after J. A Decca position coordinate could thus be written: Red I 16.30; Green D 35.80. Later receivers incorporated a microprocessor and displayed a position in latitude and longitude.

Multipulse
Multipulse provided an automatic method of lane and zone identification by using the same phase comparison techniques described above on lower frequency signals.

The nominally continuous wave transmissions were in fact divided into a 20-second cycle, with each station in turn simultaneously transmitting all four Decca frequencies (5f, 6f, 8f and 9f) in a phase-coherent relationship for a brief period of 0.45 seconds each cycle. This transmission, known as Multipulse, allowed the receiver to extract the 1f frequency and so to identify the lane that the receiver was in (to a resolution of a zone).

As well as transmitting the Decca frequencies of 5f, 6f, 8f and 9f, an 8.2f signal, known as Orange, was also transmitted. The beat frequency between the 8.0f (Red) and 8.2f (Orange) signals allowed a 0.2f signal to be derived and so resulted in a hyperbolic pattern in which one cycle (360°) of phase difference equates to 5 zones.

Assuming that one's position was known to this accuracy, this gave an effectively unique position.

Range and accuracy
During daylight, ranges of around 400 nmi could be obtained, reducing at night to 200 to 250 nmi, depending on propagation conditions.

The accuracy depended on:
 * Width of the lanes
 * Angle of cut of the hyperbolic lines of position
 * Instrumental errors
 * Propagation errors (for example, Skywave)

By day these errors could range from a few meters on the baseline up to a nautical mile at the edge of coverage. At night, skywave errors were greater and, on receivers without multipulse capabilities, it was not unusual for the position to jump a lane, sometimes without the navigator knowing.

Although in the days of differential GPS this range and accuracy may appear poor, in its day the Decca system was one of the few, if not the only, position fixing system available to many mariners. Since the need for an accurate position is less when the vessel is further from land, the reduced accuracy at long ranges was not a great problem.

Origins
In 1936 William J. O'Brien, an engineer, contracted tuberculosis that put his career on hold for a period of two years. During this period he had the idea of position fixing by means of phase comparison of continuous wave transmissions. This was not the first such system, but O'Brien apparently developed his version without knowledge of the others, and made several advancements in the art that would prove useful. He initially imagined the system being used for aircraft testing, specifically the accurate calculation of ground speed. Some experiments were carried out in California in 1938, selecting frequencies with harmonic "beats" that would allow for station identification in a network of transmitters. Both the U.S. Army and Navy considered the idea too complicated and work ended in 1939.

O’Brien's friend, Harvey F. Schwarz, was chief engineer of the Decca Record company in England. In 1939 O’Brien sent him details of the system so it could be put forward to the British military. Initially Robert Watson-Watt reviewed the system but he did not follow it up, deeming it too easily jammed (and likely due to the existing work on the Gee system, being carried out by Watt's group). However, in October 1941 the British Admiralty Signal Establishment (ASE) became interested in the system, which was then classified as Admiralty Outfit QM. The first marine trials were conducted between Anglesey and the Isle of Man, at frequencies of 305/610 kHz, on 16 September 1942.

Further trials were conducted in the northern Irish Sea in April 1943 at 70/130 kHz. It was decided that the original frequencies were not ideal, and a new system using a 14 kHz inter-signal spacing was selected. This led to the common 5, 6, 8 and 9f frequencies, used throughout the life of the Decca system. 7f was reserved for a Loran-C-like extension, but never developed. A follow-up test was carried out in the Irish Sea in January 1944 to test a wide variety of upgrades and production equipment. By this time the competing Gee system was known to the Admiralty and the two systems were tested head-to-head under the code names QM and QH. QM was found to have better sea-level range and accuracy, which led to its adoption.

D-Day landings
A three-station trial was held in conjunction with a large-scale assault and landing exercise in the Moray Firth in February/March 1944. The success of the trials and the relative ease of use and accuracy of the system resulted in Decca receiving an order for 27 Admiralty Outfit QM receivers. The receiver consisted of an electronics unit with two dials and was known to its operators as the "Blue Gasmeter Job". A Decca chain was set up, consisting of a master station at Chichester and slaves at Swanage and Beachy Head. A fourth decoy transmitter was located in the Thames Estuary as part of the deception that the invasion would be focussed on the Calais area. 21 minesweepers and other vessels were fitted with Admiralty Outfit QM and, on 5 June 1944, 17 of these ships used it to accurately navigate across the English Channel and to sweep the minefields in the planned areas. The swept areas were marked with buoys in preparation for the Normandy Landings.

After the initial ship tests, Decca conducted tests in cars, driving in the Kingston By-Pass area to verify receiver accuracy. In the car installation, it was found possible to navigate within an individual traffic lane. The company entertained high hopes that the system could be used in aircraft, to permit much more precise navigation in the critical airspace around airports and urban centres where traffic density was highest.

Commercial deployment
After the end of World War II the Decca Navigator Co. Ltd. was formed (1945) and the system expanded rapidly, particularly in areas of British influence; at its peak it was deployed in many of the world's major shipping areas. More than 15,000 receiving sets were in use aboard ships in 1970. There were 4 chains around England, 1 in Ireland and 2 in Scotland, 12 in Scandinavia (5 each in Norway and Sweden and 1 each in Denmark and Finland), a further 4 elsewhere in northern Europe and 2 in Spain.

Canada was another early user, with branch offices set up in Toronto in 1953. The first chain was installed in southwest Newfoundland in 1956 as part of a joint Canada-US Navy surveying program. This led to commercial deployments the next year in Nova Scotia and an inland system for air traffic in the busy Quebec City-Montreal area. A fourth chain covering eastern Newfoundland was added in 1958. When meetings in Montreal in 1958 led to VOR and DME being selected as the standard aviation navigation systems, the Montreal system was moved eastward to cover the Anticosti Island area of the Gulf of St. Lawrence, and the western Newfoundland chain was later repositioned to better cover the Cabot Strait. A series of chains was also proposed to cover the Northwest Passage had oil tanker traffic used the area, but this never came to be. Another was briefly set up covering Lake Ontario in 1971 for the International Field Year for the Great Lakes. The last Canadian chain shut down in 1986, after Loran-C became widespread.

In the late 1950s an experimental Decca chain was set up in the United States, in the New York area, to be used for navigating the Vertol 107 helicopters of New York Airways. These helicopters were operating from the principal local airports—Idlewild Airport on Long Island, Newark Airport in New Jersey, LaGuardia Airport in the Borough of Queens, nearer to Manhattan, and a site on the top of the (then) PanAm Building on Park Avenue. Use of Decca was essential because its signals could be received down to sea level, were not subject to the line-of-sight limitations of VOR/DME and did not suffer the slant-range errors that create problems with VOR/DME close to the transmitters. The Decca installations in the New York Airways helicopters included the unique Decca 'roller map' displays that enabled the pilot to see his or her position at a glance, a concept infeasible with VOR/DME.

This chain installation was considered highly controversial at the time, for political reasons. This led to the U.S. Coast Guard, under instructions from the Treasury Department to which it reported, banning the use of Decca receivers in ships entering New York harbour for fear that the system might create a de facto standard (as it had become in other areas of the world). It also served to protect the marketing interests of the Hoffman Electronics division of ITT, a principal supplier of VOR/DME systems, that Decca might have been poised to usurp.

This situation was exacerbated by the workload problems of the Air Traffic Controllers Association (ATCA), under its executive director Francis McDermott, whose members were forced to use radar data on aircraft positions, relaying those positions by radio to the aircraft from their control locations. An example of the problem, cited by experts, was the collision of a Douglas DC8 and a Lockheed Constellation over Staten Island, New York, that—according to some experts—could have been avoided if the aircraft had been Decca-equipped and could not only have determined their positions more precisely but would not have suffered from the rho-theta position errors inherent in VOR/DME.

Other chains were established in Japan (6 chains); Namibia and South Africa (5 chains); India and Bangladesh (4 chains); North-West Australia (2 chains); the Persian Gulf (1 chain with stations in Qatar and the United Arab Emirates and a second chain in the north of the Gulf with stations in Iran) and the Bahamas (1 chain). Four chains were planned for Nigeria but only two were built and these did not enter into public service. Two chains in Vietnam were used during the Vietnam War for helicopter navigation, with limited success. During the Cold War period, following WWII, the R.A.F. established a confidential chain in Germany. The Master station was in Bad Iburg near Osnabrück and there were two Slaves. The purpose of this chain was to provide accurate air navigation for the corridor between Western Germany and Berlin in the event that a mass evacuation of allied personnel may be required. In order to maintain secrecy, frequencies were changed at irregular intervals.

Decca, Racal, and the closedown

The headquarters of Decca Navigator were at New Malden, Surrey, just off the Kingston by-pass. There was a Decca School, at Brixham, Devon, where employees were sent on courses from time to time. Racal, the UK weapons and communications company, acquired Decca in 1980. Merging Decca's radar assets with their own, Racal began selling off the other portions of the company, including avionics and Decca Navigator.

A significant amount of income from the Decca system was due to the receivers being leased to users, not sold outright. This guaranteed predictable annual income. When the patents on the original technology lapsed in the early 1980s, new receivers were quickly built by a number of companies. In particular, Aktieselskabet Dansk Philips ('Danish Philips', ap) introduced receivers that could be purchased outright, and were much smaller and easier to use than the current Decca counterparts. The "ap" versions directly output the longitude and latitude to two decimals (originally in datum ED50 only) instead of using the "deco meter" displays, offering accuracy better than ±9.3 m, much better than the Decca units. This also eliminated the need for the special charts printed with Decca lanes and zones.

Decca sued ap for infringement and, in the ensuing court battle, Decca lost the monopoly. That signalled the beginning of the end for the company. Income dwindled and eventually, the UK Ministry of Transport stepped in, having the lighthouse authorities take responsibility for operating the system in the early 1990s.

A ruling from the European Union forced the UK government to withdraw funding. The general lighthouse authority ceased Decca transmissions at midnight on 31 March 2000. The Irish chain provided by Bórd Iascaigh Mhara continued transmitting until 19 May 2000. Japan continued operating their Hokkaidō chain until March 2001, the last Decca chain in operation.

Delrac
In the immediate post-war era, Decca began studying a long-range system like Decca, but using much lower frequencies to enable reception of skywaves at long distances. In February 1946 the company proposed a system with two main stations located at Shannon Airport in Ireland and Gander International Airport in Newfoundland (today part of Canada). Together, these stations would provide navigation over the main great circle route between London and New York. A third station in Bermuda would provide general ranging information to measure progress along the main track.

Work on this concept continued, and in 1951 a modified version was presented that offered navigation over very wide areas. This was known as Delrac, short for "Decca Long Range Area Cover". A further development, including features of the General Post Office's POPI system, was introduced in 1954, proposing 28 stations that provided worldwide coverage. The system was predicted to offer 10 mile accuracy at 2000 mile range 95% of the time. Further development was ended in favour of the Dectra system.

Dectra
In the early 1960s the Radio Technical Commission for Aeronautics (RTCA), as part of a wider ICAO effort, began the process of introducing a standard long-range radio navigation system for aviation use. Decca proposed a system that could offer both high-accuracy at short ranges and trans-Atlantic navigation with less accuracy, using a single receiver. The system was known as Dectra, short for "Decca Track".

Unlike the Delrac system, Dectra was essentially the normal Decca Navigator system with the modification of several existing transmitter sites. These were located at the East Newfoundland and Scottish chains, which were equipped with larger antennas and high-power transmitters, broadcasting 20 times as much energy as normal chain stations. Given that the length of the chain baselines did not change, and were relatively short, at long distance the signal offered almost no accuracy. Instead, Dectra operated as a track system; aircraft would navigate by keeping themselves within the signal defined by a particular Decca lane.

The main advantage of Dectra compared to other systems being proposed for the RTCA solution was that it could be used for both medium-range navigation over land, as well as long-range navigation over the Atlantic. In comparison, the VOR/DME system that ultimately won the competition offered navigation over perhaps a 200-mile radius, and could not offer a solution to the long-distance problem. Additionally, as the Decca system provided an X and Y location, as opposed to the angle-and-range VOR/DME, Decca proposed offering it with their Decca Flight Log moving map display to further improve ease of navigation. In spite of these advantages, the RTCA ultimately chose VOR/DME for two primary reasons; VOR offered coverage over about the same range as Decca, about 200 miles, but did so with a single transmitter instead of Decca's four, and Decca's frequencies proved susceptible to interference from static due to lightning, while VOR's higher frequencies were not quite as sensitive.

Decca continued to propose that Dectra be used for the long-range role. In 1967 they installed another transmitter in Iceland to provide ranging along the Scotland-Newfoundland track, with a second proposed to be installed on the Azores. They also installed Dectra receivers with Omnitrac computers and a lightweight version of the Flight Log on a number of commercial airliners, notably a BOAC Vickers VC10. The Omnitrac could take inputs from Decca (and Dectra), Loran-C, VOR/DME, an air data computer and doppler radars and combine them all to produce a lat/long output along with bearing, distance-to-go, bearing and an autopilot coupling. Their efforts to standardize this were eventually abandoned as inertial navigation systems began to be installed for these needs.

Hi-Fix
A more accurate system named Hi-Fix was developed using signalling in the 1.6 MHz range. It was used for specialised applications such as precision measurements involved with oil-drilling and by the Royal Navy for detailed mapping and surveying of coasts and harbours. The Hi-Fix equipment was leased for a period with temporary chains established to provide coverage of the area required, Hi-Fix was commercialised by Racal Survey in the early 1980s. An experimental chain was installed with coverage of central London and receivers placed in London buses and other vehicles to demonstrate an early vehicle location and tracking system. Each vehicle would report its location automatically via a conventional VHF two-way radio link, the data added to a voice channel.

Another application was developed by the Bendix Pacific division of Bendix Corporation, with offices in North Hollywood, California, but not deployed: PFNS—Personal Field Navigation System—that would enable individual soldiers to ascertain their geographic position, long before this capability was made possible by the satellite-based GPS (Global Positioning System).

A further application of the Decca system was implemented by the U.S. Navy in the late 1950s and early 1960s for use in the Tongue of the Ocean/Eleuthera Sound area near The Bahamas, separating the islands of Andros and New Providence. The application was for sonar studies made possible by the unique characteristics of the ocean floor.

An interesting characteristic of the Decca VLF signal discovered on BOAC, later British Airways, test flights to Moscow, was that the carrier switching could not be detected even though the carrier could be received with sufficient strength to provide navigation. Such testing, involving civilian aircraft, is quite common and may well not be in the knowledge of a pilot.

The 'low frequency' signalling of the Decca system also permitted its use on submarines. One 'enhancement' of the Decca system was to offer the potential of keying the signal, using Morse code, to signal the onset of nuclear war. This option was never taken up by the UK government. Messages were clandestinely sent, however, between Decca stations thereby bypassing international telephone calls, especially in non-UK chains.

Special DECCA towers

 * Puckeridge DECCA tower
 * Zeven DECCA-transmitter

title: Decca Navigator System