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Green flash

The green flash and green ray are meteorological optical phenomena that sometimes occur transiently around the moment of sunset or sunrise. When the conditions are right, a distinct green spot is briefly visible above the Sun's upper limb; the green appearance usually lasts for no more than two seconds. Rarely, the green flash can resemble a green ray shooting up from the sunset or sunrise point.

Green flashes occur because the Earth's atmosphere can cause the light from the Sun to separate, or refract, into different colors. Green flashes are a group of similar phenomena that stem from slightly different causes, and therefore, some types of green flashes are more common than others.

Observing
Green flashes may be observed from any altitude. They usually are seen at an unobstructed horizon, such as over the ocean, but are possible over cloud tops and mountain tops as well. They may occur at any latitude, although at the equator, the flash rarely lasts longer than a second.

The green flash also may be observed in association with the Moon and bright planets at the horizon, including Venus and Jupiter. With an unrestricted view of the horizon, green flashes are regularly seen by airline pilots, particularly when flying westwards as the sunset is slowed. If the atmosphere is layered, the green flash may appear as a series of flashes.

While observing at the Vatican Observatory in 1960, D.J.K. O'Connell produced the first color photograph of the green flash at sunset.

Explanation
Green flash occurs because the atmosphere causes the light from the Sun to separate, or refract, into different frequencies. Green flashes are enhanced by mirages, which increase refraction. A green flash is more likely to be seen in stable, clear air, when more of the light from the setting sun reaches the observer without being scattered. One might expect to see a blue flash, since blue light is refracted most of all and the blue component of the sun's light is therefore the last to disappear below the horizon, but the blue is preferentially scattered out of the line of sight, and the remaining light ends up appearing green.

With slight magnification, a green rim on the top of the solar disk may be seen on most clear-day sunsets, although the flash or ray effects require a stronger layering of the atmosphere and a mirage, which serves to magnify the green from a fraction of a second to a couple of seconds.

In addition to atmospheric refraction and lensing, another primary cause of the Green Flash may be due to a phenomenon recently discovered by researchers at the Washington University School of Medicine, which found that when two photons of infrared light collide with a human retina cell, causing what researchers there call "a double hit," it creates the perception of bright neon green. The researchers at Washington University in St. Louis discovered this inadvertently while working with powerful infrared lasers, which should have been invisible to them, yet the researchers consistently kept seeing bright green flashes from the source of the laser. Because the Green Flash occurs exactly where we would expect the bulk of refracted infrared sunlight (just beyond red but not by much), the most likely hypothesis is that the Green Flash is refracted and magnified infrared light that "double-hits" the retina or camera lens, creating the effect of bright green.

Types
The "green flash" description relates to a group of optical phenomena, some of which are listed below:

The majority of flashes observed are inferior-mirage or mock-mirage effects, with the others constituting only 1% of reports. Some types not listed in the table above, such as the cloud-top flash (seen as the Sun sinks into a coastal fog, or at distant cumulus clouds), are not understood.

Blue flashes
On rare occasion, the amount of blue light is sufficient to be visible as a "blue flash".

Green rim

As an astronomical object sets or rises in relation to the horizon, the light it emits travels through Earth's atmosphere, which works as a prism separating the light into different colors. The color of the upper rim of an astronomical object could go from green to blue to violet depending on the decrease in concentration of pollutants as they spread throughout an increasing volume of atmosphere. The lower rim of an astronomical object is always red. A green rim is very thin and is difficult or impossible to see with the naked eye. In usual conditions, a green rim of an astronomical object gets fainter when an astronomical object is very low above the horizon because of atmospheric reddening, but sometimes the conditions are right to see a green rim just above the horizon.

The following quote describes what was probably the longest observation of a green rim, which at times could have been a green flash. It was seen on and off for 35 minutes by members of the Richard Evelyn Byrd party from the Antarctic Little America exploration base in 1934:

"There was a rush for the surface and as eyes turned southward, they saw a tiny but brilliant green spot where the last ray of the upper rim of the sun hung on the skyline. It lasted an appreciable length of time, several seconds at least, and no sooner disappeared than it flashed forth again. Altogether it remained on the horizon with short interruptions for thirty-five minutes. When it disappeared momentarily it seemed to have been shut off by a tiny spurt, an inequality in the skyline caused by the barrier surface. Even by moving the head up a few inches it would disappear and reappear again and after it had finally disappeared from view it could be recaptured by climbing up the first few steps of the antanea [sic] post."

For the explorers to have seen a green rim on and off for 35 minutes, there must have been some mirage effect present.

A green rim is present at every sunset, but it is too thin to be seen with the naked eye. Often a green rim changes to a green flash and back again during the same sunset. The best time to observe a green rim is about 10 minutes before sunset. That is too early to use any magnification like binoculars or a telescope to look directly at the Sun without potential harm to the eyes. (Of course, a magnified image might be projected onto a sheet of paper for safe viewing.) As the Sun gets closer to the horizon, the green rim becomes fainter due to atmospheric reddening. According to the above, it is probably correct to conclude that although a green rim is present during every sunset, a green flash is rarer because of the required mirage.

In popular culture
Jules Verne's 1882 novel The Green Ray helped to popularize the green flash phenomenon.

Walt Disney Pictures' 2007 movie Pirates of the Caribbean: At World's End references the green flash as a signal that a soul had returned from the dead.

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Unicorn

The unicorn is a legendary creature that has been described since antiquity as a beast with a single large, pointed, spiraling horn projecting from its forehead.

In European literature and art, the unicorn has for the last thousand years or so been depicted as a white horse- or goat-like animal with a long straight horn with spiralling grooves, cloven hooves, and sometimes a goat's beard. In the Middle Ages and Renaissance, it was commonly described as an extremely wild woodland creature, a symbol of purity and grace, which could be captured only by a virgin. In encyclopedias, its horn was described as having the power to render poisoned water potable and to heal sickness. In medieval and Renaissance times, the tusk of the narwhal was sometimes sold as a unicorn horn.

A bovine type of unicorn is thought by some scholars to have been depicted in seals of the Bronze Age Indus Valley civilization, the interpretation remaining controversial. An equine form of the unicorn was mentioned by the ancient Greeks in accounts of natural history by various writers, including Ctesias, Strabo, Pliny the Younger, Aelian, and Cosmas Indicopleustes. The Bible also describes an animal, the re'em, which some translations render as unicorn.

The unicorn continues to hold a place in popular culture. It is often used as a symbol of fantasy or rarity. In the 21st century, it has become an LGBT symbol.

Indus Valley civilization
A creature with a single horn, conventionally called a unicorn, is the most common image on the soapstone stamp seals of the Bronze Age Indus Valley civilization ("IVC"), from the centuries around 2000 BC. It has a body more like a cow than a horse, and a curved horn that goes forward, then up at the tip. The mysterious feature depicted coming down from the front of the back is usually shown; it may represent a harness or other covering. Typically, the unicorn faces a vertical object with at least two stages; this is variously described as a "ritual offering stand", an incense burner, or a manger. The animal is always in profile on Indus seals, but the theory that it represents animals with two horns, one hiding the other, is disproved by a (much smaller) number of small terracotta unicorns, probably toys, and the profile depictions of bulls, where both horns are clearly shown. It is thought that the unicorn was the symbol of a powerful "clan or merchant community", but may also have had some religious significance.

In South Asia, the unicorn is only seen during the IVC period, and disappeared in South Asian art after this. Jonathan Mark Kenoyer stated the IVC "unicorn" has no "direct connection" with later unicorn motifs observed in other parts of the world; nonetheless, it remains possible that the IVC unicorn had contributed to later myths of fantastical one-horned creatures in West Asia.

Classical antiquity
Unicorns are not found in Greek mythology, but rather in the accounts of natural history, for Greek writers of natural history were convinced of the reality of unicorns, which they believed lived in India, a distant and fabulous realm for them. The earliest description is from Ctesias, who in his book Indika ("On India") described them as wild asses, fleet of foot, having a horn a cubit and a half (700 mm) in length, and colored white, red and black. Unicorn meat was said to be too bitter to eat.

Ctesias got his information while living in Persia. Unicorns or, more likely, winged bulls, appear in reliefs at the ancient Persian capital of Persepolis in Iran. Aristotle must be following Ctesias when he mentions two one-horned animals, the oryx (a kind of antelope) and the so-called "Indian ass" (ἰνδικὸς ὄνος). Antigonus of Carystus also wrote about the one-horned "Indian ass". Strabo says that in the Caucasus there were one-horned horses with stag-like heads. Pliny the Elder mentions the oryx and an Indian ox (perhaps a greater one-horned rhinoceros) as one-horned beasts, as well as "a very fierce animal called the monoceros which has the head of the stag, the feet of the elephant, and the tail of the boar, while the rest of the body is like that of the horse; it makes a deep lowing noise, and has a single black horn, which projects from the middle of its forehead, two cubits [900 mm] in length." In On the Nature of Animals (Περὶ Ζῴων Ἰδιότητος, De natura animalium), Aelian, quoting Ctesias, adds that India produces also a one-horned horse (iii. 41; iv. 52), and says (xvi. 20) that the  (μονόκερως) was sometimes called  (καρτάζωνος), which may be a form of the Arabic, meaning 'rhinoceros'.

Cosmas Indicopleustes, a merchant of Alexandria who lived in the 6th century, made a voyage to India and subsequently wrote works on cosmography. He gives a description of a unicorn based on four brass figures in the palace of the King of Ethiopia. He states, from report, that "it is impossible to take this ferocious beast alive; and that all its strength lies in its horn. When it finds itself pursued and in danger of capture, it throws itself from a precipice, and turns so aptly in falling, that it receives all the shock upon the horn, and so escapes safe and sound".

Middle Ages and Renaissance

Medieval knowledge of unicorns stemmed from biblical and ancient sources, and unicorns were variously represented as a kind of wild ass, goat, or horse.

Several European medieval travelers claimed to have seen unicorns in their travels outside of Europe. For example Felix Fabri claimed to have seen a unicorn in Sinai.

The predecessor of the medieval bestiary, compiled in Late Antiquity and known as (Φυσιολόγος), popularized an elaborate allegory in which a unicorn, trapped by a maiden (representing the Virgin Mary), stood for the Incarnation. As soon as the unicorn sees her, it lays its head on her lap and falls asleep. This became a basic emblematic tag that underlies medieval notions of the unicorn, justifying its appearance in both secular and religious art. The unicorn is often shown hunted, raising parallels both with vulnerable virgins and sometimes the Passion of Christ. The myths refer to a beast with one horn that can only be tamed by a virgin; subsequently, some writers translated this into an allegory for Christ's relationship with the Virgin Mary.

The unicorn also figured in courtly terms: for some 13th-century French authors such as Thibaut of Champagne and Richard de Fournival, the lover is attracted to his lady as the unicorn is to the virgin. With the rise of humanism, the unicorn also acquired more orthodox secular meanings, emblematic of chaste love and faithful marriage. It plays this role in Petrarch's Triumph of Chastity, and on the reverse of Piero della Francesca's portrait of Battista Strozzi, paired with that of her husband Federico da Montefeltro (painted c. 1472–74), Bianca's triumphal car is drawn by a pair of unicorns.

However, when the unicorn appears in the medieval legend of Barlaam and Josaphat, ultimately derived from the life of the Buddha, it represents death, as the Golden Legend explains. Unicorns in religious art largely disappeared after they were condemned by Molanus after the Council of Trent.

The unicorn, tamable only by a virgin woman, was well established in medieval lore by the time Marco Polo described them as "scarcely smaller than elephants. They have the hair of a buffalo and feet like an elephant's. They have a single large black horn in the middle of the forehead... They have a head like a wild boar's... They spend their time by preference wallowing in mud and slime. They are very ugly brutes to look at. They are not at all such as we describe them when we relate that they let themselves be captured by virgins, but clean contrary to our notions." It is clear that Marco Polo was describing a rhinoceros.

Alicorn
The horn itself and the substance it was made of was called alicorn, and it was believed that the horn holds magical and medicinal properties. The Danish physician Ole Worm determined in 1638 that the alleged alicorns were the tusks of narwhals. Such beliefs were examined wittily and at length in 1646 by Sir Thomas Browne in his Pseudodoxia Epidemica.

False alicorn powder, made from the tusks of narwhals or horns of various animals, was sold in Europe for medicinal purposes as late as 1741. The alicorn was thought to cure many diseases and have the ability to detect poisons, and many physicians would make "cures" and sell them. Cups were made from alicorn for kings and given as a gift; these were usually made of ivory or walrus ivory. Entire horns were very precious in the Middle Ages and were often really the tusks of narwhals.

Entrapment
One traditional method of hunting unicorns involved entrapment by a virgin.

In one of his notebooks Leonardo da Vinci wrote:

"The unicorn, through its intemperance and not knowing how to control itself, for the love it bears to fair maidens forgets its ferocity and wildness; and laying aside all fear it will go up to a seated damsel and go to sleep in her lap, and thus the hunters take it."

The famous late Gothic series of seven tapestry hangings The Hunt of the Unicorn are a high point in European tapestry manufacture, combining both secular and religious themes. The tapestries now hang in the Cloisters division of the Metropolitan Museum of Art in New York City. In the series, richly dressed noblemen, accompanied by huntsmen and hounds, pursue a unicorn against mille-fleur backgrounds or settings of buildings and gardens. They bring the animal to bay with the help of a maiden who traps it with her charms, appear to kill it, and bring it back to a castle; in the last and most famous panel, "The Unicorn in Captivity", the unicorn is shown alive again and happy, chained to a pomegranate tree surrounded by a fence, in a field of flowers. Scholars conjecture that the red stains on its flanks are not blood but rather the juice from pomegranates, which were a symbol of fertility. However, the true meaning of the mysterious resurrected unicorn in the last panel is unclear. The series was woven about 1500 in the Low Countries, probably Brussels or Liège, for an unknown patron. A set of six engravings on the same theme, treated rather differently, were engraved by the French artist Jean Duvet in the 1540s.

Another famous set of six tapestries of Dame à la licorne ("Lady with the unicorn") in the Musée de Cluny, Paris, were also woven in the Southern Netherlands before 1500, and show the five senses (the gateways to temptation) and finally Love ("A mon seul desir" the legend reads), with unicorns featured in each piece. Facsimiles of these unicorn tapestries were woven for permanent display in Stirling Castle, Scotland, to take the place of a set recorded in the castle in a 16th-century inventory.

A rather rare, late-15th-century, variant depiction of the hortus conclusus in religious art combined the Annunciation to Mary with the themes of the Hunt of the Unicorn and Virgin and Unicorn, so popular in secular art. The unicorn already functioned as a symbol of the Incarnation and whether this meaning is intended in many prima facie secular depictions can be a difficult matter of scholarly interpretation. There is no such ambiguity in the scenes where the archangel Gabriel is shown blowing a horn, as hounds chase the unicorn into the Virgin's arms, and a little Christ Child descends on rays of light from God the Father. The Council of Trent finally banned this somewhat over-elaborated, if charming, depiction, partly on the grounds of realism, as no one now believed the unicorn to be a real animal.

Shakespeare scholars describe unicorns being captured by a hunter standing in front of a tree, the unicorn goaded into charging; the hunter would step aside the last moment and the unicorn would embed its horn deeply into the tree (See annotations of Timon of Athens, Act 4, scene 3, c. line 341: "wert thou the unicorn, pride and wrath would confound thee and make thine own self the conquest of thy fury".)

Heraldry
In heraldry, a unicorn is often depicted as a horse with a goat's cloven hooves and beard, a lion's tail, and a slender, spiral horn on its forehead (non-equine attributes may be replaced with equine ones). Whether because it was an emblem of the Incarnation or of the fearsome animal passions of raw nature, the unicorn was not widely used in early heraldry, but became popular from the 15th century. Though sometimes shown collared and chained, which may be taken as an indication that it has been tamed or tempered, it is more usually shown collared with a broken chain attached, showing that it has broken free from its bondage.

Scotland
In heraldry the unicorn is best known as a symbol of Scotland: the unicorn was believed to be the natural enemy of the lion – a symbol that the English royals had adopted around a hundred years before Two unicorns supported the royal arms of the King of Scots and Duke of Rothesay, and since the 1707 union of England and Scotland, the royal arms of the United Kingdom have been supported by a unicorn along with an English lion. Two versions of the royal arms exist: that used in Scotland gives more emphasis to the Scottish elements, placing the unicorn on the left and giving it a crown, whereas the version used in England and elsewhere gives the English elements more prominence. John Guillim, in his book; A Display of Heraldry, has illustrated the unicorn as a symbol of power, honor and respect.

Golden coins known as the unicorn and half-unicorn, both with a unicorn on the obverse, were used in Scotland in the 15th and 16th century. In the same realm, carved unicorns were often used as finials on the pillars of Mercat crosses, and denoted that the settlement was a royal burgh. Certain noblemen such as the Earl of Kinnoull were given special permission to use the unicorn in their arms, as an augmentation of honour. The crest for Clan Cunningham bears a unicorn head.

Gallery
Unicorns as heraldic charges:

Queer culture

By the beginning of the 21st century, unicorns became a queer icon, second only to the rainbow flag, symbolizing queerness. The rainbow flag, created by American artist Gilbert Baker in 1978 as a joyous symbol of the diversity of the queer community, became prominent during the gay rights protests of the 1970s and 1980s. Unicorns, which were intrinsically linked to rainbows since the Victorian era, became symbol of the queer community.

There is no consensus on how the unicorn became a gay icon. Alice Fisher, an editor of Observer Design magazine, notes that the values of a unicorn – as rare and magical – have resulted in the word being used with various connotations. However, she argues that the Victorian association between rainbows and unicorns has resulted in unicorns becoming a queer icon.

When directly asked, queer people give different answers about why they have close personal relationships with unicorns. They often relate to one or more of the following aspects: uniqueness, magical quality, elusiveness and gender fluidity.

Queer individuals tend to relate to the unicorn because of their unique sexual orientation and gender identity. A New Orleans journalist, Tracey Anne Duncan, described her connection to unicorn when she watched The Last Unicorn as a child. In the film, the protagonist believed she was one of a kind throughout her life. Tracey was able to relate to that feeling, even though she did not really know what "her kind" was at that time.

The unicorn is an imaginary animal that lives in a world of myths and legends. Queer people, whose existence seems to blur the lines between societal norms of masculinity and femininity, may feel like they do not fully belong in this world. It explains their interests in mythical creatures such as unicorns, mermaids, and fairies.

Some argue that the gender fluidity of the unicorn makes it a suitable representation of the LGBT community. In ancient myths, the unicorn is portrayed as male, whereas in the modern times, it is depicted as a female creature.

Biblical
An animal called the re'em (רְאֵם) is mentioned in several places in the Hebrew Bible, often as a metaphor representing strength. The allusions to the re'em as a wild, untamable animal of great strength and agility, with mighty horn or horns best fit the aurochs (Bos primigenius); this view is further supported by the Assyrian cognate word rimu, which is often used as a metaphor of strength, and is depicted as a powerful, fierce, wild mountain bull with large horns. This animal was often depicted in ancient Mesopotamian art in profile, with only one horn visible.

The translators of the Authorized King James Version of the Bible (1611) followed the Greek Septuagint (monokeros) and the Latin Vulgate (unicornis) and employed unicorn to translate re'em, providing a recognizable animal that was proverbial for its untamable nature. The American Standard Version translates this term "wild ox" in each case.

 * "God brought them out of Egypt; he hath as it were the strength of an unicorn."—
 * "God brought him forth out of Egypt; he hath as it were the strength of an unicorn."—
 * "His glory is like the firstling of his bullock, and his horns are like the horns of unicorns: with them he shall push the people together to the ends of the earth."—
 * "Will the unicorn be willing to serve thee, or abide by thy crib? Canst thou bind the unicorn with his band in the furrow? or will he harrow the valleys after thee? Wilt thou trust him, because his strength is great? or wilt thou leave thy labour to him? Wilt thou believe him, that he will bring home thy seed, and gather it into thy barn?"—
 * "Save me from the lion's mouth; for thou hast heard me from the horns of unicorns."—
 * "He maketh them [the cedars of Lebanon] also to skip like a calf; Lebanon and Sirion like a young unicorn."—
 * "But my horn shalt thou exalt like the horn of the unicorn: I shall be anointed with fresh oil."—
 * "And the unicorns shall come down with them, and the bullocks with their bulls; and their land shall be soaked with blood, and their dust made fat with fatness."—

The classical Jewish understanding of the Bible did not identify the Re'em animal as the unicorn. However, some rabbis in the Talmud debate the proposition that the Tahash animal (Exodus 25, 26, 35, 36 and 39; Numbers 4; and Ezekiel 16:10) was a domestic, single-horned kosher creature that existed in Moses' time, or that it was similar to the keresh animal described in Marcus Jastrow's Talmudic dictionary as "a kind of antelope, unicorn".

Chinese mythology
The qilin, a creature in Chinese mythology, is sometimes called "the Chinese unicorn", and some ancient accounts describe a single horn as its defining feature. However, it is more accurately described as a hybrid animal that looks less unicorn than chimera, with the body of a deer, the head of a lion, green scales and a long forwardly-curved horn. The Japanese version (kirin) more closely resembles the Western unicorn, even though it is based on the Chinese qilin. The Quẻ Ly of Vietnamese myth, similarly sometimes mistranslated "unicorn" is a symbol of wealth and prosperity that made its first appearance during the Duong dynasty, about 600 CE, to Emperor Duong Cao To, after a military victory which resulted in his conquest of Tây Nguyên. In November 2012 the History Institute of the DPRK Academy of Social Sciences, as well as the Korea News Service, reported that the Kiringul had been found, which is associated with a kirin ridden by King Dongmyeong of Goguryeo.

Beginning in the Ming dynasty, the qilin became associated with giraffes, after Zheng He's voyage to East Africa brought a pair of the long-necked animals and introduced them at court in Nanjing as qilin. The resemblance to the qilin was noted in the giraffe's ossicones (bony protrusions from the skull resembling horns), graceful movements, and peaceful demeanor.

Shanhaijing (117) mentioned the Bo-horse, a chimera horse with an ox tail, a single horn, a white body, and a sound like a person calling. The creature was said to live at Honest-head Mountain. Guo Pu in his jiangfu said that the Bo-horse was able to walk on water. Another similar creature, also mentioned in Shanhaijing (80) and said to live in Mount Winding-Centre, was the Bo, but it had a black tail, tiger's teeth and claws, devoured leopards and tigers.

Hornless unicorn
It was probably thought that, like other horned animals, the unicorn's horn grew after birth. In the The Lady and the Unicorn tapestry set of (c. 1500), it has been claimed that the Taste tapestry shows a young unicorn without a horn among the animals in the millefleur background, above the two women.

The alabaster burial monument of Henry Manners, 2nd Earl of Rutland shows a hornless unicorn at his feet.

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title: Unicorn


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Thomas Telford

Thomas Telford (9 August 1757 – 2 September 1834) was a Scottish civil engineer. After establishing himself as an engineer of road and canal projects in Shropshire, he designed numerous infrastructure projects in his native Scotland, as well as harbours and tunnels. Such was his reputation as a prolific designer of highways and related bridges, he was dubbed the Colossus of Roads (a pun on the Colossus of Rhodes), and, reflecting his command of all types of civil engineering in the early 19th century, he was elected as the first president of the Institution of Civil Engineers, a post he held for 14 years until his death.

The town of Telford in Shropshire was named after him.

Early career
Telford was born on 9 August 1757, at Glendinning, a hill farm 3 mi east of Eskdalemuir Kirk, in the rural parish of Westerkirk, in Eskdale, Dumfriesshire. His father John Telford, a shepherd, died soon after Thomas was born. Thomas was raised in poverty by his mother Janet Jackson (died 1794). At the age of 14, he was apprenticed to a stonemason, and some of his earliest work can still be seen on the bridge across the River Esk in Langholm in Dumfries and Galloway. He worked for a time in Edinburgh and in 1782 he moved to London where, after meeting architects Robert Adam and Sir William Chambers, he was involved in building additions to Somerset House there. Two years later he found work at Portsmouth dockyard and – although still largely self-taught – was extending his talents to the specification, design and management of building projects.

In 1787, through his wealthy patron William Pulteney, he became Surveyor of Public Works in Shropshire. His projects included renovation of Shrewsbury Castle, the town's prison (during the planning of which he met leading prison reformer John Howard), the Church of St. Mary Magdalene, Bridgnorth and another church, St Michael, in Madeley. Called in to advise on a leaking roof at St Chad's Church, Shrewsbury in 1788, he warned the church was in imminent danger of collapse; his reputation was made locally when it collapsed 3 days later, but he was not the architect for its replacement.

As the Shropshire county surveyor, Telford was also responsible for bridges. In 1790 he designed a bridge carrying the London–Holyhead road over the River Severn at Montford, the first of some 40 bridges he built in Shropshire, including major crossings of the Severn at Buildwas, and Bridgnorth. The bridge at Buildwas was Telford's first iron bridge. He was influenced by Abraham Darby's bridge at Ironbridge, and observed that it was grossly over-designed for its function, and many of the component parts were poorly cast. By contrast, his bridge was 30 ft wider in span and half the weight, although it now no longer exists. He was one of the first engineers to test his materials thoroughly before construction. As his engineering prowess grew, Telford was to return to this material repeatedly.

In 1795, the bridge at Bewdley in Worcestershire was swept away in the winter floods and Telford was responsible for the design of its replacement. The same winter floods saw the bridge at Tenbury also swept away. This bridge across the River Teme was the joint responsibility of both Worcestershire and Shropshire and the bridge has a bend where the two counties meet. Telford was responsible for the repair to the northern (Shropshire) end of the bridge.

Ellesmere Canal
Telford's reputation in Shropshire led to his appointment in 1793 to manage the detailed design and construction of the Ellesmere Canal, linking the ironworks and collieries of Wrexham via the north-west Shropshire town of Ellesmere, with Chester, utilising the existing Chester Canal, and then the River Mersey.

Among other structures, this involved the spectacular Pontcysyllte Aqueduct over the River Dee in the Vale of Llangollen, where Telford used a new method of construction consisting of troughs made from cast iron plates and fixed in masonry. Extending for over 1000 ft with an altitude of 126 ft above the valley floor, the Pontcysyllte Aqueduct consists of nineteen arches, each with a 45 ft span. Being a pioneer in the use of cast-iron for large scaled structures, Telford had to invent new techniques, such as using boiling sugar and lead as a sealant on the iron connections. Eminent canal engineer William Jessop oversaw the project, but he left the detailed execution of the project in Telford's hands. The aqueduct was designated a UNESCO World Heritage Site in 2009. The same period also saw Telford involved in the design and construction of the Shrewsbury Canal. When the original engineer, Josiah Clowes, died in 1795, Telford succeeded him. One of Telford's achievements on this project was the design of Longdon-on-Tern Aqueduct, the cast-iron aqueduct at Longdon-on-Tern, pre-dating that at Pontcysyllte, and substantially bigger than the UK's first cast-iron aqueduct, built by Benjamin Outram on the Derby Canal just months earlier. The aqueduct is no longer in use, but is preserved as a distinctive piece of canal engineering.

The Ellesmere Canal was left uncompleted in 1805 because it failed to generate the revenues needed to finance the connecting sections to Chester and Shrewbury. However, alongside his canal responsibilities, Telford's reputation as a civil engineer meant he was constantly consulted on numerous other projects. These included water supply works for Liverpool, improvements to London's docklands and the rebuilding of London Bridge (c. 1800).

Most notably (and again William Pulteney was influential), in 1801 Telford devised a master plan to improve communications in the Highlands of Scotland, a massive project that was to last some 20 years. It included the building of the Caledonian Canal along the Great Glen and redesign of sections of the Crinan Canal, some 920 mi of new roads, over a thousand new bridges (including the Craigellachie Bridge), numerous harbour improvements (including works at Aberdeen, Dundee, Peterhead, Wick, Portmahomack and Banff), and 32 new churches.

Telford also undertook highway works in the Scottish Lowlands, including 184 mi of new roads and numerous bridges, ranging from a 112 ft (34 m) span stone bridge across the Dee at Tongueland in Kirkcudbright (1805–06) to the 129 ft (39 m) tall Cartland Crags bridge near Lanark (1822).

In 1809, Telford was tasked with improving the Howth Road in Dublin, to connect the new harbour at Howth to the city of Dublin as part of wider plan to improve communication between Dublin and London. The milestones that are a feature of this route from Howth to the GPO on O'Connell Street still mark the route. He also drafted the first design of the Ulster Canal. Irish engineer, William Dargan, was trained by Telford.

Telford was consulted in 1806 by the King of Sweden about the construction of a canal between Gothenburg and Stockholm. His plans were adopted and construction of the Göta Canal began in 1810. Telford travelled to Sweden at that time to oversee some of the more important initial excavations.

Many of Telford's projects were undertaken due to his role as a member of the Exchequer Bill Loan Commission, an organ set up under the Poor Employment Act of 1817, to help finance public work projects that would generate employment.

The 'Colossus of Roads'
During his later years, Telford was responsible for rebuilding sections of the London to Holyhead road, a task completed by his assistant of ten years, John MacNeill; today, much of the route is the A5 trunk road, although the Holyhead Road diverted off the A5 along what is now parts of A45, A41 and A464 through the cities of Coventry, Birmingham and Wolverhampton. Between London and Shrewsbury, most of the work amounted to improvements. Beyond Shrewsbury, and especially beyond Llangollen, the work often involved building a highway from scratch. Notable features of this section of the route include the Waterloo Bridge across the River Conwy at Betws-y-Coed, the ascent from there to Capel Curig and then the descent from the pass of Nant Ffrancon towards Bangor. Between Capel Curig and Bethesda, in the Ogwen Valley, Telford deviated from the original road, built by Romans during their occupation of this area.

On the island of Anglesey a new embankment across the Stanley Sands to Holyhead was constructed, but the crossing of the Menai Strait was the most formidable challenge, overcome by the Menai Suspension Bridge (1819–26). Spanning 580 ft, this was the longest suspension bridge of the time. Unlike modern suspension bridges, Telford used individually linked 9.5 ft iron eye bars for the cables.

Telford also worked on the North Wales coast road between Chester and Bangor, including another major suspension bridge at Conwy, opened later the same year as its Menai counterpart.

Further afield Telford designed a road to cross the centre of the Isle of Arran. Named the 'String road', this route traverses bleak and difficult terrain to allow traffic to cross between east and west Arran avoiding the circuitous coastal route. His work on improving the Glasgow – Carlisle road, later to become the A74, has been described as "a model for future engineers."

Telford improved on methods for the building of macadam roads by improving the selection of stone based on thickness, taking into account traffic, alignment and slopes.

The punning nickname Colossus of Roads was given to Telford by his friend, the eventual Poet Laureate, Robert Southey.

In 1821, he was elected a foreign member of the Royal Swedish Academy of Sciences.

The 'Telford Church'
An Act of Parliament in 1823 provided a grant of £50,000 for the building of up to 40 churches and manses in communities without any church buildings (hence the alternative name: 'Parliamentary Church' or 'Parliamentary Kirk'). The total cost was not to exceed £1500 on any site and Telford was commissioned to undertake the design. He developed a simple church of T-shaped plan and two manse designs – a single-storey and a two-storey, adaptable to site and ground conditions, and to brick or stone construction, at £750 each. Of the 43 churches originally planned, 32 were eventually built around the Scottish highlands and islands (the other 11 were achieved by redoing existing buildings). The last of these churches was built in 1830. Some have been restored and/or converted to private use.

Late career
Other works by Telford include the St Katharine Docks (1824–28) close to Tower Bridge in central London, where he worked with the architect Philip Hardwick, the Gloucester and Berkeley Ship Canal (today known as the Gloucester and Sharpness Canal), Over Bridge near Gloucester, the second Harecastle Tunnel on the Trent and Mersey Canal (1827), and the Birmingham and Liverpool Junction Canal (today part of the Shropshire Union Canal) – started in May 1826 but finished, after Telford's death, in January 1835. At the time of its construction in 1829, Galton Bridge was the longest single span in the world. Telford surveyed and planned the Macclesfield Canal, which was completed by William Crosley (or Crossley). He also built Whitstable harbour in Kent in 1832, in connection with the Canterbury and Whitstable Railway with an unusual system for flushing out mud using a tidal reservoir. He also completed the Grand Trunk after James Brindley died due to being over-worked.

In 1820, Telford was appointed the first President of the recently formed Institution of Civil Engineers, a post he held until his death.

Freemasonry
He was Initiated into Freemasonry in Antiquity Lodge, No. 26, (Portsmouth, England) in 1770. This lodge no longer exists. He was a founder member of Phoenix Lodge, No. 257 (also in Portsmouth). Telford designed a room within the George Inn for the lodge. In 1786 he became an affiliate member of Salopian Lodge, No. 262 (Shrewsbury, England).

Telford's death
Telford's young draughtsman and clerk 1830–34 George Turnbull in his diary states: "On the 23rd [August 1834] Mr Telford was taken seriously ill of a bilious derangement to which he had been liable … he grew worse and worse … [surgeons] attended him twice a day, but it was to no avail for he died on the 2nd September, very peacefully at about 5pm. … His old servant James Handscombe and I were the only two in the house [24 Abingdon Street, London] when he died. He was never married. Mr Milne and Mr Rickman were, no doubt, Telford's most intimate friends. … I went to Mr Milne and under his direction … made all the arrangements about the house and correspondence. … Telford had no blood relations that we knew of. The funeral took place on the 10th September [in Westminster Abbey]. … Mr Telford was of the most genial disposition and a delightful companion, his laugh was the heartiest I ever heard; it was a pleasure to be in his society."

Thomas Telford was buried in the nave of Westminster Abbey; a statue was erected to him nearby, in St Andrew's Chapel adjoining the north transept.

Throughout his life Telford had a great affection for his birthplace of Eskdale and its people and in his will left legacies to the two local libraries at Westerkirk and Langholm.

Honours
In 2011 he was one of seven inaugural inductees to the Scottish Engineering Hall of Fame.

Telford the poet
Telford's reputation as a man of letters may have preceded his fame as an engineer: he had published poetry between 1779 and 1784, and an account of a tour of Scotland with Robert Southey. His will left bequests to Southey (who would later write Telford's biography), the poet Thomas Campbell (1777–1844) and to the publishers of the Edinburgh Encyclopædia (to which he had been a contributor).

George Turnbull states that Telford wrote and gave him a poem:

(Turnbull includes notes that explain nine references to Burns's life in the poem.)

Turnbull also states:

"His ability and perseverance may be understood from various literary compositions of after life, such as the articles he contributed to the Edinburgh Encyclopædia, such as Architecture, Bridge-building, and Canal-making. Singular to say the earliest distinction he acquired in life was as a poet. Even at 30 years of age he reprinted at Shrewsbury a poem called 'Eskdale', … Some others of his poems are in my possession."

Another example, later in Telford's life, was To Sir John Malcolm on Receiving His Miscellaneous Poems (1831).

Bridges designed by Telford

Telford designed many bridges and aqueducts during his career. They include:

Places named after Telford
Telford is commemorated in the names of many sites:
 * Telford New Town;
 * Thomas Telford School;
 * Thomas Telford Road, Langholm, where Telford was an apprentice in his early years;
 * Telford Hall, a hall of residence at Loughborough University. A plaque in his honour hangs in the hall's common room;
 * Telford, Pennsylvania, the Borough of County Line in Montgomery County, Pennsylvania changed its name to Telford in 1857, after the North Pennsylvania Railroad Company named its new station there "Telford" in honour of Thomas Telford;
 * Telford College, Edinburgh;
 * Telford Bridge (footbridge), in 2008, a footbridge was erected over the Shubenacadie Canal in Dartmouth, Nova Scotia and named for Telford, who made important contributions to the nineteenth-century Canadian canal;
 * Thomas Telford Basin, part of a residential development on the Ashton Canal in Manchester.

Autobiography
Telford's autobiography, titled The Life of Thomas Telford, Civil Engineer, written by himself, was published posthumously in 1838.

People acquainted with Thomas Telford

 * Charles Atherton, fellow civil engineer
 * Hugh Baird (engineer), fellow civil engineer
 * Hamilton Fulton, fellow civil engineer
 * John Gibb (engineer), fellow civil engineer
 * William Hazledine, supplied ironwork for many projects of Thomas Telford
 * William Jessop, fellow civil engineer
 * John Benjamin Macneill, fellow civil engineer
 * Sir William Pulteney, 5th Baronet, patron of Thomas Telford
 * William Reynolds (industrialist), constructed Longdon-on-Tern Aqueduct for Telford
 * George Turnbull (civil engineer), fellow civil engineer

title: Thomas Telford


text:
Talk:Green flash

Comment
PAGE IS A MESS, pictures over text and vice versa. Someone clean it up? I don't know how.Mzmadmike 14:43, 5 May 2007 (UTC)

The current article seems to balance the different viewing opportunities, ". . usually seen at an unobstructed horizon, such as over the ocean, but are possible over cloud-tops and mountain-tops as well." I can't speak to viewing over cloud tops but I have seen it from sea level in Kenai, Alaska looking west over 4,000-foot mountains. The sun had just set into a distinct notch in the horizon so it does not have to be a flat horizon. And I know a reliable viewer who saw a green flash from the Sierra Nevada range in California (8,000 feet?) while looking over the Coast Range (2,000-4,000 feet). DavidinKenai (talk) 16:55, 27 March 2009 (UTC)

Previously the article said that you both needed a low line of hills and an unobstructed view of the horizon. I kept the unobstructed view as I know an amateur astronomer who just saw it for the first time last month over the ocean. Is there any reason a low line of hills would also work? --rmhermen

A key issue seems to be atmospheric layering and 'the right conditions'. It could be a low line of hills would help keep things still and enhance the layering? User:Rjstott In any event the effect is enhanced by a low horizon.

 * I've seen it just once, but quite impressive. Like all other references I recall, it was over the ocean, seen from the waterfront. All references I recall also call it the green flash, so I'm thinking that might be the preferred page title, but maybe others' experience differs?--Richard Jones 13:28, 20 Mar 2004 (UTC)

Page title
(William M. Connolley 20:15, 11 Oct 2004 (UTC)) I think the common name for this is green flash. green ray is less common. Google gives GF 35k and GR 9k (but this is complicated by other things that match). This page even says that GR and GF are different things!

 * I just moved it to "Green flash" and I mentioned that green ray and green flash are not completely synonymous. AxelBoldt 23:47, 19 May 2005 (UTC)

Picture
This page needs a picture. It would be nice if we could find an uncopyrighted one, or if someone would take one (easier said than done, I know) and release it under the GFDL. Wmahan. 21:58, 24 September 2005 (UTC)

Green flash in the media
Does this refer to the green flash legend from the Florida Keys? If so, I could reference Carl Hiassen's new book "Flush" in this article. (I'm actually reading it right now, so I thought I'd ask...) Mattderojas 23:24, 19 January 2006 (UTC)
 * I recently did a whole slew of research on the Green Flash and hope to greatly expand the article when I have time. I was recently reading Flush, too, and I was surprised when I read about the Green Flash. I added it to the article. -- M  @  th  wiz  2020  01:24, 20 January 2006 (UTC)

Floridian literature and Floridians themselves, up and down the peninsula, are steeped in the green flash. I added a reference to a well-known example, the 1962 novel A Flash of Green by John D. MacDonald, who arrived in Florida in 1949. The 1984 film by Victor Nuñez (Ulee's Gold) starring Ed Harris is an adaptation of the MacDonald novel. Rt3368 (talk) 02:01, 30 January 2008 (UTC)

Blue flash
"Very occasionally, the amount of blue light is sufficient to be visible as a "blue flash". (This is not to be confused with the blue flash reported to occur during nuclear criticality accidents.)" – HA HA HA, who the hell would confuse a blue flash of the setting sun with a nuclear criticality accident? :P Bossk-Office 00:31, 1 May 2007 (UTC)

 * Someone seeing it suddenly, while otherwise engaged, during a threat scenario. Unlikely, but possible.  Would you prefer they didn't specify?  But seriously, people come to an encyclopedia because they don't know the answer.  If there are two answers, they need access to both. Mzmadmike 14:42, 5 May 2007 (UTC)

 * It's not the two phenomena which are confusable, it's the fact that the same term is used to name them. The wording was obviously an attempt at disambiguating the usage, which is valid since someone searching for 'blue flash' will be led here.220.239.3.5 00:50, 11 July 2007 (UTC)

On Tuesday afternoon at around 6 pm December 9, 2014 I was at Ke'e beach, Ha'ena, Kauai to observe the sun set over the ocean, the only location in North Kauai you can see the sun set over the ocean at this time of year. It soon became apparent that I would not see the sun set on the ocean as there was a dark layer of cloud just covering the horizon. But even better, I watched the sun as the tip disappeared when it went down behind the cloud and saw the most gorgeous PURPLE BLUE flash. (The previous day, with no clouds on the horizon, also with binoculars, I had seen an excellent emerald flash.) Very enjoyable. 69.199.125.229 (talk) 03:50, 21 December 2014 (UTC)Dr. Raymond Schep.

removing pictures
Everybody, before you remove a picture, please, ask yourself few quesions: "What do I know about green flashes? How many I've seen myself and am I really qualified to decide what picture to remove?" Thank you. Mbz1
 * Wikipedia is not your image repository. Please do not get upset because someone removed one or mroe of the eight hojillion images you added to this page.  Jeez. Assume good faith, my friend.  Assume good faith. // 24.250.125.206 13:15, 25 September 2007 (UTC)

I hope no one minds, I removed the fourth image (an animation) as I didn't think it added anything and was pretty jerky. The image above has something very similar running across the bottom as a film strip. I also re-arranged the text to make to formatting better. I think the article looks fine now but content could do with some work. Seems like a good subject

CaptinJohn 15:45, 25 September 2007 (UTC)
 * Please help ensure that all free-use images are uploaded to Commons, as opposed to here on the English Wikipedia. Also, please add them to the page on Commons at http://commons.wikimedia.org/wiki/Category:Green_Flash.  That way, they will still be available even if they are removed from this article.  Unlike this article, Commons pages actually are image repositories.  Thanks! JohnMGarrison (talk) 03:51, 30 May 2008 (UTC)

The Gallery section currently has 18 photos of essentially the same orange blob with a barely perceptible green tinge on top. Certainly this can reduced to only the best examples of the phenomenon. I have tagged the article appropriately so as solicit opinions as to what should be moved and/or removed. — Senator2029 (talk) 00:27, 31 July 2011 (UTC)

Acknowledgments
I'd like to thank Dr. Andy Young for his help in the writing of green rim section of the article. Not only he has the most comprehensive explanation of mirages and green flashes, not only he has the most comprehensive Annotated bibliography of mirages, green flashes, atmospheric refraction, etc., but he also responded hundreds of my questions via e-mails.--Mbz1 (talk) 18:12, 24 November 2008 (UTC)

Pirates
should it be noted that the Green Flash is used in PotC: at worlds end, where it symbolyses the soul crossing from the land of the dead? Lord loss210 (talk) 18:25, 17 January 2010 (UTC)

Speed of light
I don't know enough about the phenomenon but I'd argue with the assertion that "light moves more slowly in the lower, denser air than in the thinner air above". If anyone knows what this really means in the context of the article, please feel free to modify it (i.e. better than I feel I can). —Preceding unsigned comment added by AstroWiki (talk • contribs) 13:09, 15 July 2010 (UTC)
 * Yes it does. That is why light is refracted.JMcC (talk) 12:23, 2 October 2010 (UTC)

Fata Morgana
Is there a link to be made with Fata Morgana (mirage)? JMcC (talk) 12:23, 2 October 2010 (UTC)

Explanation of green flashes
I removed the paragraph about "There are problems with the explanation of the cause of the green flash". It was added by 207.103.7.226 without any supporting citations. Even though the index of refraction of air is very small, it can still be enough to deflect light noticeably because of the very long distance it travels through the atmosphere while undergoing small amounts of refraction. The reason the flash is so small is because most of the sun has set below the horizon. The green rim phenomenon demonstrates that the entire image of the sun can be affected: green light from the whole image is preferentially shifted upward, causing a small but noticeable green tint at the top (and red at bottom) of the image. It seems that whoever added this paragraph didn't personally understand the phenomenon, but that doesn't mean the phenomenon lacks a scientific explanation. Perhaps the intent of 207.103.7.226's edit was to request clarification in the explanation, in which case he should have edited the Talk page (and this should now clarify it). Rotiro (talk) 18:51, 23 May 2011 (UTC)

The explanation section doesn't currently include an actual explanation. Can someone source one and add it? Otherwise perhaps the secction should be renamed to reflect the text, which discusses best viewing opportunities. (Anonymous) 16:16, 14 June 2012 (UTC) — Preceding unsigned comment added by 65.216.138.253 (talk)

I agree, the explanation section urgently needs an actual explanation. This is probably what most people coming to this article are looking for. --seberle (talk) 11:29, 17 June 2012 (UTC)

How is this for an explanation, provided by (relatively) recent research at the Washington University Medical School? In synopsis, the human eye is actually capable of accidentally seeing infrared light. When strong, clear, and very bright infrared light enters the human eye, it's capable of "double hitting" a retina cell, where two infrared photons work together to become visible, while one infrared photon alone is not. So of all irony, the green flash is actually super-bright infrared being refracted and magnified like a lens by the atmosphere, double-hitting our retinas and causing a bright green sensation. I'm so curious about the reports of blue flashes and purple flashes as well. This is as much a biological phenomenon as a meteorological one- could infrared "double-hits" manifest as different colors for different people? — Preceding unsigned comment added by Carl.r.larson (talk • contribs) 05:59, 4 December 2022 (UTC)

 * Hey, me, Carl, again, I am wondering folks, does this "Green Flash" not attach conceptually to both relativity AND quantum physics (via that infrared light being quantized / up-classified / amplified in wavelength so we can see it as potentially green, blue, purple, or even could this be an explanation for why we see double (and sometimes even triple) rainbows as well? Will the theoretical equations that are written about this become the first bridges across the "Theory of Everything" that aims to unite Einstein's Relativity with the field of Quantum Physics? If we had a planetary-sized, perhaps, silicate-biotelescope driven by AI in a century from now, could we see a "Green Flash" on an exoplanet? Do the equations that govern this phenomenon require avenues that attach to relativity as well as quantum physics? Are we not looking at *a* "holy grail" of physics when we see the Green Flash? I am a believer in the "Many Paths" approach to enlightenment, and suspect there will be more theories that require equations that bridge the relativity-quantum physics gap, but this phenomenon, for one, seems to demand that of astrophysicists. I humbly need to re-read the equations and remain a conceptual / theoretical commenter, LLAP y'all! Carl.r.larson (talk) 19:49, 15 February 2023 (UTC)

File:Development of Green Flash.jpg to appear as POTD soon
Hello! This is a note to let the editors of this article know that File:Development of Green Flash.jpg will be appearing as picture of the day on October 10, 2011. You can view and edit the POTD blurb at Template:POTD/2011-10-10. If this article needs any attention or maintenance, it would be preferable if that could be done before its appearance on the Main Page so Wikipedia doesn't look bad. :) Thanks!  howcheng  {chat} 17:28, 6 October 2011 (UTC)

Explanation
The explanation section doesn't actually explain what a green flash is. It opens with 'Green flashes are enhanced by mirage', and continues in that vein. The real explanation for a green flash is found in the Green rim section. Quite odd, don't you think? Tomásdearg92 (talk) 15:21, 30 April 2013 (UTC)

 * I tend to think of a green flash in general as the last bit of the green rim being the only thing that is visible as the sun sets. Usually this would be only moderately visible. This can be magnified and made brighter by mirage effects. The green rim is caused by atmospheric dispersion, where density gradients in the atmosphere act like a prism and slightly spread out the light of low objects into a vertical spectrum. — Preceding unsigned comment added by 137.75.201.73 (talk) 18:52, 16 February 2015 (UTC)

External links modified
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 * Added archive https://web.archive.org/20111111060527/http://www.bbc.co.uk/weather/features/understanding/greenflash.shtml to http://www.bbc.co.uk/weather/features/understanding/greenflash.shtml

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Before or After Sunset (and Sunrise)?
The page currently states a green flash occurs "right after sunset or right before sunrise". However, since the precise definition of sunset is when the top edge of the sun disappears below the horizon, and the pictures clearly show the green flash while a portion of the sun is still visible, surely this should read "right before sunset or right after sunrise"? Peace Makes Plenty (talk) 15:14, 6 December 2016 (UTC)

I agree with you, according to precise definition of sunset, it should be "right before sunset or right after sunrise". 81.6.34.246 (talk) 00:16, 27 April 2018 (UTC)

Introduction
Can someone familiar with this subject review the introduction? It seems to be based on negative statements that are quite confusing (e.g. the first sentence reads "Green flashes and green rays are NOT meteorological optical phenomena that sometimes occur just before sunset or right after sunrise." emphasis added.) Shouldn't the "not" be taken out? Also, the last sentence of the intro is extremely unclear and seems to be a misinterpretation of the linked source. The source is saying that three of the four types of green flash are more common than the fourth type, if I'm reading it correctly. And please indicate what "Earth NOAA" refers to. — Preceding unsigned comment added by Michijake (talk • contribs) 20:10, 29 May 2019 (UTC)

Stars
Isn't this also related to how stars and bright planets appear to strobe red and green when they are a low angle to the horizon? The first time I ever saw it through binoculars it freaked me out, I didn't even know what it was until it rose higher in the sky and stabilized to one color.

64.222.112.139 (talk) 07:39, 10 February 2021 (UTC)

In Popular culture
The following should be added to the list of references in the "In popular culture" section A Flash of Green A Novel by John D MacDonald. Also a movie made from the novel. Referenced as follows. https://en.wikipedia.org/wiki/John_D._MacDonald And: https://www.kirkusreviews.com/book-reviews/john-d-macdonald/flash-of-green/ ˜˜˜˜ — Preceding unsigned comment added by Donslevin3 (talk • contribs) 19:05, 28 June 2021 (UTC)
 * Hello Donslevin3, and I appreciate your suggestion. I am going to say, thanks, but no thanks. There's no indication that the MacDonald novel bears any relation to the optical phenomenon known as a green flash; any similarity in the title appears to be purely based on the words alone. In any case, the In popular culture section probably needs to be trimmed. Best, Altamel (talk) 05:41, 6 July 2021 (UTC)

title: Talk:Green flash


text:
Talk:Evolution of an idea

surely the believe that ideas evolve is not original to Dawkins. How about Hegel or Bateson? SR

title: Talk:Evolution of an idea