prompt_front: Answer the question based on the given passages. Only give me the answer and do not output any other words.

Question: How many times did the plague occur in the city where Flora's painter died?

The following are given passages.
Context 1: Passage 1:
The Martyrdom of Saint Lawrence (Titian)
The Martyrdom of Saint Lawrence is a 1558 painting by Titian, now in the church of I Gesuiti in Venice  It so impressed Philip II of Spain that he commissioned a second version in 1567 for the basilica at El Escorial 

See also
List of works by Titian
Passage 2:
Black Death
The Black Death (also known as the Pestilence, the Great Mortality or the Plague) was a bubonic plague pandemic occurring in Western Eurasia and North Africa from 1346 to 1353  It is the most fatal pandemic recorded in human history, causing the deaths of 75–200 million people, peaking in Europe from 1347 to 1351  Bubonic plague is caused by the bacterium Yersinia pestis spread by fleas, but during the Black Death it probably also took a secondary form, spread by person-to-person contact via aerosols, causing pneumonic plague The Black Death was the beginning of the second plague pandemic  The plague created religious, social and economic upheavals, with profound effects on the course of European history 
The origin of the Black Death is disputed  Genetic analysis points to the evolution of Yersinia pestis in the Tian Shan mountains on the border between Kyrgyzstan and China 2,600 years ago  The immediate territorial origins of the Black Death and its outbreak remains unclear with some pointing towards Central Asia, China, the Middle East and Europe  The pandemic was reportedly first introduced to Europe during the siege of the Genoese trading port of Kaffa in Crimea by the Golden Horde army of Jani Beg in 1347  From Crimea, it was most likely carried by fleas living on the black rats that travelled on Genoese ships, spreading through the Mediterranean Basin and reaching North Africa, Western Asia and the rest of Europe via Constantinople, Sicily and the Italian Peninsula  There is evidence that once it came ashore, the Black Death mainly spread person-to-person as pneumonic plague, thus explaining the quick inland spread of the epidemic, which was faster than would be expected if the primary vector was rat fleas causing bubonic plague  In 2022, it was discovered that there was a sudden surge of deaths in what is today Kyrgyzstan from the Black Death in the late 1330s; when combined with genetic evidence, this implies that the initial spread may not have been due to Mongol conquests in the 14th century, as previously speculated The Black Death was the second great natural disaster to strike Europe during the Late Middle Ages (the first one being the Great Famine of 1315–1317) and is estimated to have killed 30 percent to 60 percent of the European population, as well as about one-third of the population of the Middle East  The plague might have reduced the world population from c  475 million to 350–375 million in the 14th century  There were further outbreaks throughout the Late Middle Ages and, with other contributing factors (the Crisis of the Late Middle Ages), the European population did not regain its level in 1300 until 1500  Outbreaks of the plague recurred around the world until the early 19th century 

Names
European writers contemporary with the plague described the disease in Latin as pestis or pestilentia, 'pestilence'; epidemia, 'epidemic'; mortalitas, 'mortality'  In English prior to the 18th century, the event was called the "pestilence" or "great pestilence", "the plague" or the "great death"  Subsequent to the pandemic "the furste moreyn" (first murrain) or "first pestilence" was applied, to distinguish the mid-14th century phenomenon from other infectious diseases and epidemics of plague The 1347 pandemic plague was not referred to specifically as "black" in the time of occurrence in any European language, though the expression "black death" had occasionally been applied to fatal disease beforehand  "Black death" was not used to describe the plague pandemic in English until the 1750s; the term is first attested in 1755, where it translated Danish: den sorte død, lit  'the black death'  This expression as a proper name for the pandemic had been popularized by Swedish and Danish chroniclers in the 15th and early 16th centuries, and in the 16th and 17th centuries was transferred to other languages as a calque: Icelandic: svarti dauði, German: der schwarze Tod, and French: la mort noire  Previously, most European languages had named the pandemic a variant or calque of the Latin: magna mortalitas, lit  'Great Death' The phrase 'black death' – describing Death as black – is very old  Homer used it in the Odyssey to describe the monstrous Scylla, with her mouths "full of black Death" (Ancient Greek: πλεῖοι μέλανος Θανάτοιο, romanized: pleîoi mélanos Thanátoio)  Seneca the Younger may have been the first to describe an epidemic as 'black death', (Latin: mors atra) but only in reference to the acute lethality and dark prognosis of disease  The 12th–13th century French physician Gilles de Corbeil had already used atra mors to refer to a "pestilential fever" (febris pestilentialis) in his work On the Signs and Symptoms of Diseases (De signis et symptomatibus aegritudium)  The phrase mors nigra, 'black death', was used in 1350 by Simon de Covino (or Couvin), a Belgian astronomer, in his poem "On the Judgement of the Sun at a Feast of Saturn" (De judicio Solis in convivio Saturni), which attributes the plague to an astrological conjunction of Jupiter and Saturn  His use of the phrase is not connected unambiguously with the plague pandemic of 1347 and appears to refer to the fatal outcome of disease The historian Cardinal Francis Aidan Gasquet wrote about the Great Pestilence in 1893 and suggested that it had been "some form of the ordinary Eastern or bubonic plague"  In 1908, Gasquet said use of the name atra mors for the 14th-century epidemic first appeared in a 1631 book on Danish history by J  I  Pontanus: "Commonly and from its effects, they called it the black death" (Vulgo & ab effectu atram mortem vocitabant) 

Previous plague epidemics
Research from 2017 suggests plague first infected humans in Europe and Asia in the Late Neolithic-Early Bronze Age  Research in 2018 found evidence of Yersinia pestis in an ancient Swedish tomb, which may have been associated with the "Neolithic decline" around 3000 BCE, in which European populations fell significantly  This Y  pestis may have been different from more modern types, with bubonic plague transmissible by fleas first known from Bronze Age remains near Samara The symptoms of bubonic plague are first attested in a fragment of Rufus of Ephesus preserved by Oribasius; these ancient medical authorities suggest bubonic plague had appeared in the Roman Empire before the reign of Trajan, six centuries before arriving at Pelusium in the reign of Justinian I  In 2013, researchers confirmed earlier speculation that the cause of the Plague of Justinian (541–542 CE, with recurrences until 750) was Y  pestis  This is known as the first plague pandemic  In 610, the Chinese physician Chao Yuanfang described a "malignant bubo" "coming in abruptly with high fever together with the appearance of a bundle of nodes beneath the tissue " The Chinese physician Sun Simo who died in 652 also mentioned a "malignant bubo" and plague that was common in Lingnan (Guangzhou)  Ole Jørgen Benedictow believes that this indicates it was an offshoot of the first plague pandemic which made its way eastward to Chinese territory by around 600 

14th-century plague
Causes
Early theory
The most authoritative contemporary account is found in a report from the medical faculty in Paris to Philip VI of France  It blamed the heavens, in the form of a conjunction of three planets in 1345 that caused a "great pestilence in the air" (miasma theory)  Muslim religious scholars taught that the pandemic was a "martyrdom and mercy" from God, assuring the believer's place in paradise  For non-believers, it was a punishment  Some Muslim doctors cautioned against trying to prevent or treat a disease sent by God  Others adopted preventive measures and treatments for plague used by Europeans  These Muslim doctors also depended on the writings of the ancient Greeks 

Predominant modern theory
Due to climate change in Asia, rodents began to flee the dried-out grasslands to more populated areas, spreading the disease  The plague disease, caused by the bacterium Yersinia pestis, is enzootic (commonly present) in populations of fleas carried by ground rodents, including marmots, in various areas, including Central Asia, Kurdistan, Western Asia, North India, Uganda and the western United States Y  pestis was discovered by Alexandre Yersin, a pupil of Louis Pasteur, during an epidemic of bubonic plague in Hong Kong in 1894; Yersin also proved this bacillus was present in rodents and suggested the rat was the main vehicle of transmission  The mechanism by which Y  pestis is usually transmitted was established in 1898 by Paul-Louis Simond and was found to involve the bites of fleas whose midguts had become obstructed by replicating Y  pestis several days after feeding on an infected host  This blockage starves the fleas and drives them to aggressive feeding behaviour and attempts to clear the blockage by regurgitation, resulting in thousands of plague bacteria being flushed into the feeding site, infecting the host  The bubonic plague mechanism was also dependent on two populations of rodents: one resistant to the disease, which act as hosts, keeping the disease endemic, and a second that lacks resistance  When the second population dies, the fleas move on to other hosts, including people, thus creating a human epidemic 

DNA evidence
Definitive confirmation of the role of Y  pestis arrived in 2010 with a publication in PLOS Pathogens by Haensch et al  They assessed the presence of DNA/RNA with polymerase chain reaction (PCR) techniques for Y  pestis from the tooth sockets in human skeletons from mass graves in northern, central and southern Europe that were associated archaeologically with the Black Death and subsequent resurgences  The authors concluded that this new research, together with prior analyses from the south of France and Germany, "ends the debate about the cause of the Black Death, and unambiguously demonstrates that Y  pestis was the causative agent of the epidemic plague that devastated Europe during the Middle Ages"  In 2011, these results were further confirmed with genetic evidence derived from Black Death victims in the East Smithfield burial site in England  Schuenemann et al  concluded in 2011 "that the Black Death in medieval Europe was caused by a variant of Y  pestis that may no longer exist" Later in 2011, Bos et al  reported in Nature the first draft genome of Y  pestis from plague victims from the same East Smithfield cemetery and indicated that the strain that caused the Black Death is ancestral to most modern strains of Y  pestis Since this time, further genomic papers have further confirmed the phylogenetic placement of the Y  pestis strain responsible for the Black Death as both the ancestor of later plague epidemics including the third plague pandemic and as the descendant of the strain responsible for the Plague of Justinian  In addition, plague genomes from significantly earlier in prehistory have been recovered DNA taken from 25 skeletons from 14th century London have shown plague is a strain of Y  pestis almost identical to that which hit Madagascar in 2013  Further DNA evidence also proves the role of Y  Pestis and traces the source to the Tian Shan Mountains in Kyrgyzstan 

Alternative explanations
It is recognised that an epidemiological account of plague is as important as an identification of symptoms, but researchers are hampered by the lack of reliable statistics from this period  Most work has been done on the spread of the disease in England, and even estimates of overall population at the start vary by over 100% as no census was undertaken in England between the time of publication of the Domesday Book of 1086 and the poll tax of the year 1377  Estimates of plague victims are usually extrapolated from figures for the clergy 
Mathematical modelling is used to match the spreading patterns and the means of transmission  A research in 2018 challenged the popular hypothesis that "infected rats died, their flea parasites could have jumped from the recently dead rat hosts to humans"  It suggested an alternative model in which "the disease was spread from human fleas and body lice to other people"  The second model claims to better fit the trends of death toll because the rat-flea-human hypothesis would have produced a delayed but very high spike in deaths, which contradict historical death data Lars Walløe complains that all of these authors "take it for granted that Simond's infection model, black rat → rat flea → human, which was developed to explain the spread of plague in India, is the only way an epidemic of Yersinia pestis infection could spread", whilst pointing to several other possibilities  Similarly, Monica Green has argued that greater attention is needed to the range of (especially non-commensal) animals that might be involved in the transmission of plague Archaeologist Barney Sloane has argued that there is insufficient evidence of the extinction of numerous rats in the archaeological record of the medieval waterfront in London and that the disease spread too quickly to support the thesis that Y  pestis was spread from fleas on rats; he argues that transmission must have been person to person  This theory is supported by research in 2018 which suggested transmission was more likely by body lice and fleas during the second plague pandemic 

Summary
Although academic debate continues, no single alternative solution has achieved widespread acceptance  Many scholars arguing for Y  pestis as the major agent of the pandemic suggest that its extent and symptoms can be explained by a combination of bubonic plague with other diseases, including typhus, smallpox and respiratory infections  In addition to the bubonic infection, others point to additional septicaemic (a type of "blood poisoning") and pneumonic (an airborne plague that attacks the lungs before the rest of the body) forms of plague, which lengthen the duration of outbreaks throughout the seasons and help account for its high mortality rate and additional recorded symptoms  In 2014, Public Health England announced the results of an examination of 25 bodies exhumed in the Clerkenwell area of London, as well as of wills registered in London during the period, which supported the pneumonic hypothesis  Currently, while osteoarcheologists have conclusively verified the presence of Y  pestis bacteria in burial sites across northern Europe through examination of bones and dental pulp, no other epidemic pathogen has been discovered to bolster the alternative explanations 

Transmission
Lack of hygiene
The importance of hygiene was recognised only in the nineteenth century with the development of the germ theory of disease; until then streets were commonly filthy, with live animals of all sorts around and human parasites abounding, facilitating the spread of transmissible disease By the early fourteenth century so much filth had collected inside urban Europe that French and Italian cities were naming streets after human waste  In medieval Paris, several street names were inspired by merde, the French word for "shit"  There were rue Merdeux, rue Merdelet, rue Merdusson, rue des Merdons and rue Merdiere—as well as a rue du Pipi Pigs, cattle, chickens, geese, goats and horses roamed the streets of medieval London and Paris  Medieval homeowners were supposed to police their housefronts, including removing animal dung, but most urbanites were as careless as William E  Cosner, a resident of the London suburb of Farringdon Without  A complaint lodged against Cosner charges that "men could not pass [by his house] for the stink [of]       horse dung and horse piss "One irate Londoner complained that the runoff from the local slaughterhouse had made his garden "stinking and putrid", while another charged that the blood from slain animals flooded nearby streets and lanes, "making a foul corruption and abominable sight to all dwelling near " In much of medieval Europe, sanitation legislation consisted of an ordinance requiring homeowners to shout, "Look out below!" three times before dumping a full chamber pot into the street Early Christians, who thought self-abnegation a cardinal virtue, considered bathing, if not a vice, then a temptation  "Who knows what impure thoughts might arise in a tub of warm water? With this danger in mind, St  Benedict declared, "To those who are well, and especially to the young, bathing shall seldom be permitted " St  Agnes took the injunction to heart and died without ever bathing 

Territorial origins
According to a team of medical geneticists led by Mark Achtman that analysed the genetic variation of the bacterium Yersinia pestis "evolved in or near China" over 2,600 years ago  Later research by a team led by Galina Eroshenko places the origins more specifically in the Tian Shan mountains on the border between Kyrgyzstan and China  However more recent research notes that the previous sampling had a very heavy East Asian bias and that sampling since then has discovered strains of Y  pestis in the Caucasus region that were previously thought to be restricted to China  There is also no physical or specific textual evidence of the Black Death in 14th century China  As a result, China's place in the sequence of the plague's spread is still debated to this day  According to Charles Creighton, records of epidemics in 14th century China suggest nothing more than typhus and major Chinese outbreaks of epidemic disease post-date the European epidemic by several years  The earliest Chinese descriptions of the bubonic plague do not appear until the 1640s Nestorian graves dating to 1338–1339 near Issyk-Kul in Kyrgyzstan have inscriptions referring to plague, which has led some historians and epidemiologists to think they mark the outbreak of the epidemic; this is supported by recent direct findings of Y  pestis DNA in teeth samples from graves in the area with inscriptions referring to "pestilence" as the cause of death  Epidemics killed an estimated 25 million across Asia during the fifteen years before the Black Death reached Constantinople in 1347 
The evidence does not suggest, at least at present, that these mortality crises were caused by plague  Although some scholars, including McNeill and Cao, see the 1333 outbreak as a prelude to the outbreaks in Europe from the late 1340s to the early 1350s, scholars of the Yuan and Ming periods remain skeptical about such an interpretation  Nonetheless, the remarkably high mortality rates during the Datong mortality should discourage us from rejecting the possibility of localized/regional outbreaks of plague in different parts of China, albeit differing in scale from, and unrelated to, the pandemic mortality of the Black Death  What we lack is any indication of a plague pandemic that engulfed vast territories of the Yuan Empire and later moved into western Eurasia through Central Asia 
According to John Norris, evidence from Issyk-Kul indicates a small sporadic outbreak characteristic of transmission from rodents to humans with no wide-scale impact  According to Achtman, the dating of the plague suggests that it was not carried along the Silk Road, and its widespread appearance in that region probably postdates the European outbreak  There are no records of the symptoms of the Black Death from Mongol sources or writings from travelers east of the Black Sea prior to the Crimean outbreak in 1346  Finally, the Silk Road had already been heavily disrupted before the spread of the Black Death  Western and Middle Eastern traders found it difficult to trade on the Silk Road by 1325 and impossible by 1340, making spread of the plague less likely Others still favor an origin in China or even Kurdistan, and not Central Asia  According to the theory of Chinese origin, the disease may have traveled along the Silk Road with Mongol armies and traders, or it could have arrived via ship, but this theory is still contested  It is speculated that rats aboard Zheng He's ships in the 15th century may have carried the plague to Southeast Asia, India and Africa 
Research on the Delhi Sultanate and the Yuan Dynasty shows no evidence of any serious epidemic in fourteenth-century India and no specific evidence of plague in fourteenth-century China, suggesting that the Black Death may not have reached these regions  Ole Benedictow argues that since the first clear reports of the Black Death come from Kaffa, the Black Death most likely originated in the nearby plague focus on the northwestern shore of the Caspian Sea 
Demographic historians estimate that China's population fell by at least 15 percent, and perhaps as much as a third, between 1340 and 1370  This population loss coincided with the Black Death that ravaged Europe and much of the Islamic world in 1347–52  However, there is a conspicuous lack of evidence for pandemic disease on the scale of the Black Death in China at this time  War and famine – and the diseases that typically accompanied them – probably were the main causes of mortality in the final decades of Mongol rule 
Monica H  Green suggests that the reason why other parts of Eurasia outside the west do not contain the same evidence of the Black Plague is because there were actually four strains of Yersinia pestis that became predominant in different parts of the world  Mongol records of illness such as food poisoning may have been referring to the Black Plague  Another theory is that the Black Death originated near Europe and cycled through the Mediterranean, Northern Europe and Russia before making its way to China  Other historians such as John Norris and Ole Benedictaw believe the Black Death likely originated in Europe or the Middle East and never reached China 

European outbreak
Plague was reportedly first introduced to Europe via Genoese traders from their port city of Kaffa in the Crimea in 1347  During a protracted siege of the city, in 1345–1346 the Mongol Golden Horde army of Jani Beg, whose mainly Tatar troops were suffering from the disease, catapulted infected corpses over the city walls of Kaffa to infect the inhabitants, though it is more likely that infected rats travelled across the siege lines to spread the epidemic to the inhabitants  As the disease took hold, Genoese traders fled across the Black Sea to Constantinople, where the disease first arrived in Europe in summer 1347 The epidemic there killed the 13-year-old son of the Byzantine emperor, John VI Kantakouzenos, who wrote a description of the disease modelled on Thucydides's account of the 5th century BCE Plague of Athens, but noting the spread of the Black Death by ship between maritime cities  Nicephorus Gregoras also described in writing to Demetrios Kydones the rising death toll, the futility of medicine, and the panic of the citizens  The first outbreak in Constantinople lasted a year, but the disease recurred ten times before 1400 Carried by twelve Genoese galleys, plague arrived by ship in Sicily in October 1347; the disease spread rapidly all over the island  Galleys from Kaffa reached Genoa and Venice in January 1348, but it was the outbreak in Pisa a few weeks later that was the entry point to northern Italy  Towards the end of January, one of the galleys expelled from Italy arrived in Marseilles From Italy, the disease spread northwest across Europe, striking France, Spain (the epidemic began to wreak havoc first on the Crown of Aragon in the spring of 1348), Portugal and England by June 1348, then spread east and north through Germany, Scotland and Scandinavia from 1348 to 1350  It was introduced into Norway in 1349 when a ship landed at Askøy, then spread to Bjørgvin (modern Bergen) and Iceland  Finally, it spread to northwestern Russia in 1351  Plague was somewhat more uncommon in parts of Europe with less developed trade with their neighbours, including the majority of the Basque Country, isolated parts of Belgium and the Netherlands, and isolated Alpine villages throughout the continent According to some epidemiologists, periods of unfavourable weather decimated plague-infected rodent populations and forced their fleas onto alternative hosts, inducing plague outbreaks which often peaked in the hot summers of the Mediterranean, as well as during the cool autumn months of the southern Baltic region  Among many other culprits of plague contagiousness, malnutrition, even if distantly, also contributed to such an immense loss in European population, since it weakened immune systems 

Western Asian and North African outbreak
The disease struck various regions in the Middle East and North Africa during the pandemic, leading to serious depopulation and permanent change in both economic and social structures  As infected rodents infected new rodents, the disease spread across the region, entering also from southern Russia 
By autumn 1347, plague had reached Alexandria in Egypt, transmitted by sea from Constantinople; according to a contemporary witness, from a single merchant ship carrying slaves  By late summer 1348 it reached Cairo, capital of the Mamluk Sultanate, cultural centre of the Islamic world, and the largest city in the Mediterranean Basin; the Bahriyya child sultan an-Nasir Hasan fled and more than a third of the 600,000 residents died  The Nile was choked with corpses despite Cairo having a medieval hospital, the late 13th century bimaristan of the Qalawun complex  The historian al-Maqrizi described the abundant work for grave-diggers and practitioners of funeral rites, and plague recurred in Cairo more than fifty times over the following one and a half centuries During 1347, the disease travelled eastward to Gaza by April; by July it had reached Damascus, and in October plague had broken out in Aleppo  That year, in the territory of modern Lebanon, Syria, Israel and Palestine, the cities of Ascalon, Acre, Jerusalem, Sidon and Homs were all infected  In 1348–1349, the disease reached Antioch  The city's residents fled to the north, but most of them ended up dying during the journey  Within two years, the plague had spread throughout the Islamic world, from Arabia across North Africa  The pandemic spread westwards from Alexandria along the African coast, while in April 1348 Tunis was infected by ship from Sicily  Tunis was then under attack by an army from Morocco; this army dispersed in 1348 and brought the contagion with them to Morocco, whose epidemic may also have been seeded from the Islamic city of Almería in al-Andalus Mecca became infected in 1348 by pilgrims performing the Hajj  In 1351 or 1352, the Rasulid sultan of the Yemen, al-Mujahid Ali, was released from Mamluk captivity in Egypt and carried plague with him on his return home  During 1348, records show the city of Mosul suffered a massive epidemic, and the city of Baghdad experienced a second round of the disease 

Signs and symptoms
Bubonic plague
Symptoms of the disease include fever of 38–41 °C (100–106 °F), headaches, painful aching joints, nausea and vomiting, and a general feeling of malaise  Left untreated, of those that contract the bubonic plague, 80 percent die within eight days Contemporary accounts of the pandemic are varied and often imprecise  The most commonly noted symptom was the appearance of buboes (or gavocciolos) in the groin, neck and armpits, which oozed pus and bled when opened  Boccaccio's description:

In men and women alike it first betrayed itself by the emergence of certain tumours in the groin or armpits, some of which grew as large as a common apple, others as an egg     From the two said parts of the body this deadly gavocciolo soon began to propagate and spread itself in all directions indifferently; after which the form of the malady began to change, black spots or livid making their appearance in many cases on the arm or the thigh or elsewhere, now few and large, now minute and numerous  As the gavocciolo had been and still was an infallible token of approaching death, such also were these spots on whomsoever they showed themselves 
This was followed by acute fever and vomiting of blood  Most people died two to seven days after initial infection  Freckle-like spots and rashes, which could have been caused by flea-bites, were identified as another potential sign of plague 

Pneumonic plague
Lodewijk Heyligen, whose master the Cardinal Colonna died of plague in 1348, noted a distinct form of the disease, pneumonic plague, that infected the lungs and led to respiratory problems  Symptoms include fever, cough and blood-tinged sputum  As the disease progresses, sputum becomes free-flowing and bright red  Pneumonic plague has a mortality rate of 90 to 95 percent 

Septicaemic plague
Septicaemic plague is the least common of the three forms, with a mortality rate near 100%  Symptoms are high fevers and purple skin patches (purpura due to disseminated intravascular coagulation)  In cases of pneumonic and particularly septicaemic plague, the progress of the disease is so rapid that there would often be no time for the development of the enlarged lymph nodes that were noted as buboes 

Consequences
Deaths
There are no exact figures for the death toll; the rate varied widely by locality  In urban centres, the greater the population before the outbreak, the longer the duration of the period of abnormal mortality  It killed some 75 to 200 million people in Eurasia  A study published in 2022 of pollen samples across Europe between 1250 and 1450 was used to estimate changes in agricultural output before and after the Black Death  The authors found great variability in different regions, with evidence for high mortality in areas of Scandinavia, France, western Germany, Greece and central Italy, but uninterrupted agricultural growth in central and eastern Europe, Iberia and Ireland The mortality rate of the Black Death in the 14th century was far greater than the worst 20th-century outbreaks of Y  pestis plague, which occurred in India and killed as much as 3% of the population of certain cities  The overwhelming number of deceased bodies produced by the Black Death caused the necessity of mass burial sites in Europe, sometimes including up to several hundred or several thousand skeletons  The mass burial sites that have been excavated have allowed archaeologists to continue interpreting and defining the biological, sociological, historical and anthropological implications of the Black Death According to medieval historian Philip Daileader, it is likely that over four years, 45–50% of the European population died of plague  Norwegian historian Ole Benedictow suggests it could have been as much as 60% of the European population  In 1348, the disease spread so rapidly that before any physicians or government authorities had time to reflect upon its origins, about a third of the European population had already perished  In crowded cities, it was not uncommon for as much as 50% of the population to die  Half of Paris' population of 100,000 people died  In Italy, the population of Florence was reduced from between 110,000 and 120,000 inhabitants in 1338 down to 50,000 in 1351  At least 60% of the population of Hamburg and Bremen perished, and a similar percentage of Londoners may have died from the disease as well, with a death toll of approximately 62,000 between 1346 and 1353  Florence's tax records suggest that 80% of the city's population died within four months in 1348  Before 1350, there were about 170,000 settlements in Germany, and this was reduced by nearly 40,000 by 1450  The disease bypassed some areas, with the most isolated areas being less vulnerable to contagion  Plague did not appear in Douai in Flanders until the turn of the 15th century, and the impact was less severe on the populations of Hainaut, Finland, northern Germany and areas of Poland  Monks, nuns and priests were especially hard-hit since they cared for people with the Black Death 

The physician to the Avignon Papacy, Raimundo Chalmel de Vinario (Latin: Magister Raimundus, lit  'Master Raymond'), observed the decreasing mortality rate of successive outbreaks of plague in 1347–48, 1362, 1371 and 1382 in his 1382 treatise On Epidemics (De epidemica)  In the first outbreak, two thirds of the population contracted the illness and most patients died; in the next, half the population became ill but only some died; by the third, a tenth were affected and many survived; while by the fourth occurrence, only one in twenty people were sickened and most of them survived  By the 1380s in Europe, it predominantly affected children  Chalmel de Vinario recognised that bloodletting was ineffective (though he continued to prescribe bleeding for members of the Roman Curia, whom he disliked), and said that all true cases of plague were caused by astrological factors and were incurable; he himself was never able to effect a cure The most widely accepted estimate for the Middle East, including Iraq, Iran and Syria, during this time, is for a death toll of about a third of the population  The Black Death killed about 40% of Egypt's population  In Cairo, with a population numbering as many as 600,000, and possibly the largest city west of China, between one third and 40% of the inhabitants died within eight months Italian chronicler Agnolo di Tura recorded his experience from Siena, where plague arrived in May 1348:

Father abandoned child, wife husband, one brother another; for this illness seemed to strike through the breath and sight  And so they died  And none could be found to bury the dead for money or friendship  Members of a household brought their dead to a ditch as best they could, without priest, without divine offices     great pits were dug and piled deep with the multitude of dead  And they died by the hundreds both day and night     And as soon as those ditches were filled more were dug     And I, Agnolo di Tura     buried my five children with my own hands  And there were also those who were so sparsely covered with earth that the dogs dragged them forth and devoured many bodies throughout the city  There was no one who wept for any death, for all awaited death  And so many died that all believed it was the end of the world 

Economic
It has been suggested that the plague, like some others in history, disproportionately affected the poorest people, who were already in generally worse physical condition than the wealthier citizens   Nevertheless, with such a large overall population decline from the pandemic, wages soared in response to a labour shortage  On the other hand, in the quarter century after the Black Death in England, it is clear many labourers, artisans and craftsmen, those living from money-wages alone, did suffer a reduction in real incomes owing to rampant inflation  Landowners were also pushed to substitute monetary rents for labour services in an effort to keep tenants 

Environmental
A study performed by Thomas Van Hoof of the Utrecht University suggests that the innumerable deaths brought on by the pandemic cooled the climate by freeing up land and triggering reforestation  This may have led to the Little Ice Age 

Persecutions
Renewed religious fervour and fanaticism bloomed in the wake of the Black Death  Some Europeans targeted "various groups such as Jews, friars, foreigners, beggars, pilgrims", lepers and Romani, blaming them for the crisis  Lepers, and others with skin diseases such as acne or psoriasis, were killed throughout Europe 
Because 14th-century healers and governments were at a loss to explain or stop the disease, Europeans turned to astrological forces, earthquakes and the poisoning of wells by Jews as possible reasons for outbreaks  Many believed the epidemic was a punishment by God for their sins, and could be relieved by winning God's forgiveness There were many attacks against Jewish communities  In the Strasbourg massacre of February 1349, about 2,000 Jews were murdered  In August 1349, the Jewish communities in Mainz and Cologne were annihilated  By 1351, 60 major and 150 smaller Jewish communities had been destroyed  During this period many Jews relocated to Poland, where they received a warm welcome from King Casimir the Great 

Social
One theory that has been advanced is that the devastation in Florence caused by the Black Death, which hit Europe between 1348 and 1350, resulted in a shift in the world view of people in 14th-century Italy and led to the Renaissance  Italy was particularly badly hit by the pandemic, and it has been speculated that the resulting familiarity with death caused thinkers to dwell more on their lives on Earth, rather than on spirituality and the afterlife  It has also been argued that the Black Death prompted a new wave of piety, manifested in the sponsorship of religious works of art This does not fully explain why the Renaissance occurred in Italy in the 14th century  The Black Death was a pandemic that affected all of Europe in the ways described, not only Italy  The Renaissance's emergence in Italy was most likely the result of the complex interaction of the above factors, in combination with an influx of Greek scholars following the fall of the Byzantine Empire  As a result of the drastic reduction in the populace the value of the working class increased, and commoners came to enjoy more freedom  To answer the increased need for labour, workers travelled in search of the most favorable position economically Prior to the emergence of the Black Death, the workings of Europe were run by the Catholic Church and the continent was considered a feudalistic society, composed of fiefs and city-states  The pandemic completely restructured both religion and political forces; survivors began to turn to other forms of spirituality and the power dynamics of the fiefs and city-states crumbled Cairo's population, partly owing to the numerous plague epidemics, was in the early 18th century half of what it was in 1347  The populations of some Italian cities, notably Florence, did not regain their pre-14th century size until the 19th century  The demographic decline due to the pandemic had economic consequences: the prices of food dropped and land values declined by 30–40% in most parts of Europe between 1350 and 1400  Landholders faced a great loss, but for ordinary men and women it was a windfall  The survivors of the pandemic found not only that the prices of food were lower but also that lands were more abundant, and many of them inherited property from their dead relatives, and this probably destabilised feudalism The word "quarantine" has its roots in this period, though the concept of isolating people to prevent the spread of disease is older  In the city-state of Ragusa (modern Dubrovnik, Croatia), a thirty-day isolation period was implemented in 1377 for new arrivals to the city from plague-affected areas  The isolation period was later extended to forty days, and given the name "quarantino" from the Italian word for "forty" 

Recurrences
Second plague pandemic
The plague repeatedly returned to haunt Europe and the Mediterranean throughout the 14th to 17th centuries  According to Jean-Noël Biraben, the plague was present somewhere in Europe in every year between 1346 and 1671  (Note that some researchers have cautions about the uncritical use of Biraben's data ) The second pandemic was particularly widespread in the following years: 1360–63; 1374; 1400; 1438–39; 1456–57; 1464–66; 1481–85; 1500–03; 1518–31; 1544–48; 1563–66; 1573–88; 1596–99; 1602–11; 1623–40; 1644–54; and 1664–67  Subsequent outbreaks, though severe, marked the retreat from most of Europe (18th century) and northern Africa (19th century)  The historian George Sussman argued that the plague had not occurred in East Africa until the 1900s  However, other sources suggest that the Second pandemic did indeed reach Sub-Saharan Africa According to historian Geoffrey Parker, "France alone lost almost a million people to the plague in the epidemic of 1628–31 " In the first half of the 17th century, a plague killed some 1 7 million people in Italy  More than 1 25 million deaths resulted from the extreme incidence of plague in 17th-century Spain The Black Death ravaged much of the Islamic world  Plague could be found in the Islamic world almost every year between 1500 and 1850  Sometimes the outbreaks affected small areas, while other outbreaks affected multiple regions  Plague repeatedly struck the cities of North Africa  Algiers lost 30,000–50,000 inhabitants to it in 1620–21, and again in 1654–57, 1665, 1691 and 1740–42  Cairo suffered more than fifty plague epidemics within 150 years from the plague's first appearance, with the final outbreak of the second pandemic there in the 1840s  Plague remained a major event in Ottoman society until the second quarter of the 19th century  Between 1701 and 1750, thirty-seven larger and smaller epidemics were recorded in Constantinople, and an additional thirty-one between 1751 and 1800  Baghdad has suffered severely from visitations of the plague, and sometimes two-thirds of its population had died 

Third plague pandemic
The third plague pandemic (1855–1859) started in China in the mid-19th century, spreading to all inhabited continents and killing 10 million people in India alone  The investigation of the pathogen that caused the 19th-century plague was begun by teams of scientists who visited Hong Kong in 1894, among whom was the French-Swiss bacteriologist Alexandre Yersin, after whom the pathogen was named Twelve plague outbreaks in Australia between 1900 and 1925 resulted in well over 1,000 deaths, chiefly in Sydney  This led to the establishment of a Public Health Department there which undertook some leading-edge research on plague transmission from rat fleas to humans via the bacillus Yersinia pestis The first North American plague epidemic was the San Francisco plague of 1900–1904, followed by another outbreak in 1907–1908 

Modern-day
Modern treatment methods include insecticides, the use of antibiotics, and a plague vaccine  It is feared that the plague bacterium could develop drug resistance and again become a major health threat  One case of a drug-resistant form of the bacterium was found in Madagascar in 1995  A further outbreak in Madagascar was reported in November 2014  In October 2017, the deadliest outbreak of the plague in modern times hit Madagascar, killing 170 people and infecting thousands An estimate of the case fatality rate for the modern bubonic plague, following the introduction of antibiotics, is 11%, although it may be higher in underdeveloped regions 

See also
Black Death in England
Black Death in medieval culture
Crisis of the Late Middle Ages
Flagellant
Globalization and disease
List of epidemics
Second plague pandemic
Timeline of plague
Passage 3:
Black Death in England
The Black Death was a bubonic plague pandemic, which reached England in June 1348  It was the first and most severe manifestation of the second pandemic, caused by Yersinia pestis bacteria  The term Black Death was not used until the late 17th century 
Originating in Asia, it spread west along the trade routes across Europe and arrived on the British Isles from the English province of Gascony  The plague was spread by flea-infected rats, as well as individuals who had been infected on the continent  Rats were the reservoir hosts of the Y  pestis bacteria and the Oriental rat flea was the primary vector 
The first-known case in England was a seaman who arrived at Weymouth, Dorset, from Gascony in June 1348  By autumn, the plague had reached London, and by summer 1349 it covered the entire country, before dying down by December  Low estimates of mortality in the early twentieth century have been revised upwards due to re-examination of data and new information, and a figure of 40–60 percent of the population is widely accepted 
The most immediate consequence was a halt to the campaigns of the Hundred Years' War  In the long term, the decrease in population caused a shortage of labour, with subsequent rise in wages, resisted by the landowners, which caused deep resentment among the lower classes  The Peasants' Revolt of 1381 was largely a result of this resentment, and even though the rebellion was suppressed, in the long term serfdom was ended in England  The Black Death also affected artistic and cultural efforts, and may have helped advance the use of the vernacular 
In 1361–62 the plague returned to England, this time causing the death of around 20 per cent of the population  After this the plague continued to return intermittently throughout the 14th and 15th centuries, in local or national outbreaks  From this point on its effect became less severe, and one of the last outbreaks of the plague in England was the Great Plague of London in 1665–1666 

Background
England in the mid-14th century
It is impossible to establish with any certainty the exact number of inhabitants in England at the eve of the Black Death, and estimates range from 3 to 7 million  The number is probably in the higher end, and an estimate of around 6 million inhabitants seems likely  Earlier demographic crises—in particular the Great Famine of 1315–1317—had resulted in great numbers of deaths, but there is no evidence of any significant decrease in the population prior to 1348  England was still a predominantly rural and agrarian society; close to 90 per cent of the population lived in the countryside  Of the major cities, London was in a class of its own, with perhaps as many as 70,000 inhabitants  Further down the scale were Norwich, with around 12,000 people, and York with around 10,000  The main export, and the source of the nation's wealth, was wool  Until the middle of the century the export had consisted primarily of raw wool to cloth makers in Flanders  Gradually though, the technology for cloth making used on the Continent was appropriated by English manufacturers, who started an export of cloths around mid-century that would boom over the following decades Politically, the kingdom was evolving into a major European power, through the youthful and energetic kingship of Edward III  In 1346, the English had won a decisive battle over the Scots at the Battle of Neville's Cross, and it seemed that Edward III would realise his grandfather Edward I's ambition of bringing the Scots under the suzerainty of the English crown  The English were also experiencing military success on the continent  Less than two months before the Battle of Neville's Cross, a numerically inferior English army led by the king himself won a spectacular victory over the French royal forces at the Battle of Crécy  The victory was immediately followed by Edward laying siege to the port city of Calais  When the city fell the next year, this provided the English with a strategically important enclave that would remain in their possession for over two centuries 

The Black Death
The term "Black Death"—which refers to the first and most serious outbreak of the second pandemic—was not used by contemporaries, who preferred such names as the "Great Pestilence" or the "Great Mortality"  It was not until the 17th century that the term under which we know the outbreak today became common, probably derived from Scandinavian languages  It is generally agreed today that the disease in question was plague, caused by Yersinia pestis bacteria  These bacteria are carried by fleas, which can be transferred to humans through contact with rats  Flea bites carry the disease into the lymphatic system, through which it makes its way to the lymph nodes  Here the bacteria multiply and form swellings called buboes, from which the term bubonic plague is derived  After three or four days the bacteria enter the bloodstream, and infect organs such as the spleen and the lungs  The patient will then normally die after a few days  A different strain of the disease is pneumonic plague, where the bacteria become airborne and enter directly into the patient's lungs  This strain is far more virulent, as it spreads directly from person to person  These types of infection probably both played a significant part in the Black Death, while a third strain was more rare  This is the septicaemic plague, where the flea bite carries the bacteria directly into the blood stream, and death occurs very rapidly A study reported in 2011 of skeletons exhumed from the Black Death cemetery in East Smithfield, London, found Yersinia pestis DNA  An archaeological dig in the vicinity of Thornton Abbey in Lincolnshire was reported in the science section of The Guardian for 30 November 2016, not only confirming evidence of the Y  pestis DNA in the human remains exhumed there but also dating the remains to mid-1349 
Genotyping showed that it was [at that time] a newly evolved strain, ancestor of all modern strains and proved the Black Death was bubonic plague  Modern medical knowledge suggests that because it was a new strain, the human immune system would have had little or no defence against it, helping to explain the plague's virulence and high death rates The Black Death seems to have originated in Central Asia, where the Y  pestis bacterium is endemic in the rodent population  It is unknown exactly what caused the outbreak, but a series of natural occurrences likely brought humans into contact with the infected rodents  The epidemic reached Constantinople in the late spring of 1347, through Genoese merchants trading in the Black Sea  From here it reached Sicily in October that same year, and by early 1348 it had spread over the entire Italian mainland  It spread rapidly through France, and had reached as far north as Paris by June 1348  Moving simultaneously westward, it arrived in the English province of Gascony around the same time 

Progress of the plague
According to the chronicle of the grey friars at King's Lynn, the plague arrived by ship from Gascony to Melcombe in Dorset—today normally referred to as Weymouth—shortly before the Feast of St  John the Baptist on 24 June 1348  Other sources mention different points of arrival, including Bristol and Southampton  Though the plague might have arrived independently at Bristol at a later point, the Grey Friars' Chronicle is considered the most authoritative account  If it is assumed that the chronicle reports the first outbreak of the plague, rather than its actual arrival, then the arrival most likely happened around 8 May From Weymouth the disease spread rapidly across the south-west  The first major city to be struck was Bristol  The disease reached London in the autumn of 1348, before most of the surrounding countryside  This had certainly happened by November, though according to some accounts as early as 29 September  Arrival in London happened by three principal roads: overland from Weymouth—through Salisbury and Winchester—overland from Gloucester, and along the coast by ship  The full effect of the plague was felt in the capital early the next year  Conditions in London were ideal for the plague: the streets were narrow and flowing with sewage, and houses were overcrowded and poorly ventilated  By March 1349 the disease was spreading haphazardly across all of southern England During the first half of 1349 the Black Death spread northwards  A second front opened up when the plague arrived by ship at the Humber, after which it spread both south and north  In May it reached York, and during the summer months of June, July and August, it ravaged the north  Certain northern counties, like Durham and Cumberland, had been the victim of violent incursions from the Scots, and were therefore left particularly vulnerable to the devastations of the plague  Pestilence is less virulent during the winter months, and spreads less rapidly  The Black Death in England had survived the winter of 1348–49, but during the following winter it gave in, and by December 1349 conditions were returning to relative normality  It had taken the disease approximately 500 days to traverse the entire country 

Medical practice
Various methods were used including sweating, bloodletting, forced vomiting and urinating to treat patients infected with the plague  Several symptoms of the illness included blotches, hardening of the glands under the groin and underarms, and dementia  Within the initial phase of the disease, bloodletting was performed on the same side of where the physical manifestations of the buboes or risings appeared  For instance, if a rising appeared on the right side of the groin the physician would bleed a vein in the ankle on the same side  In the case of sweating, it was achieved with such medicines as Mithridate, Venice-Treacle, Matthiolus, Bezoar-Water, Serpentary Roots and Electuarium de Ovo  Sweating was used when measures were desperate; if a patient had tokens, a severe version of risings, the physician would wrap the naked patient in a blanket drenched in cold water  This measure was only performed while the patient still had natural heat in his system  The desired effect was to make the patient sweat violently and thus purge all corruption from the blood which was caused by the disease Another practice was the use of pigeons when treating swellings  Swellings which were white in appearance and deep were unlikely to break and were anointed with Oil of Lillies or Camomil  Once the swelling rose to a head and was red in appearance and not deep in the flesh, it was broken with the use of a feather from a young pigeon's tail  The feather's fundament was held to the swelling and would draw out the venom  However, if the swelling dropped and became black in appearance, the physician had to be cautious when drawing the cold from the swelling  If it was too late to prevent, the physician would take the young pigeon, cut it open from breast to back, break it open and apply the pigeon (while still alive) over the cold swelling  The cupping therapy was an alternative method which was heated and then placed over the swellings  Once the sore was broken, the physician would apply Mellilot Plaister with Linimentum Arcei and heal the sore with digence 

Victims
Death toll
Although historical records for England were more extensive than those of any other European country, it is still extremely difficult to establish the death toll with any degree of certainty  Difficulties involve uncertainty about the size of the total population, as described above, but also issues regarding the proportion of the population that died from the plague  Contemporary accounts are often grossly inflated, stating numbers as high as 90 per cent  Modern historians give estimates of death rates ranging from around 25 per cent to more than 60 per cent of the total population 
The pioneering work in the field was made by Josiah William Russell in his 1948 British Medieval Population  Russell looked at inquisitions post mortem (IPMs)—taken by the crown to assess the wealth of the greatest landowners after their death—to assess the mortality caused by the Black Death, and from this arrived at an estimate of 23 6 per cent of the entire population  He also looked at episcopal registers for the death toll among the clergy, where the result was between 30 and 40 per cent  Russell believed the clergy was at particular risk of contagion, and eventually concluded with a low mortality level of only 20 per cent Several of Russell's assumptions have been challenged, and the tendency since has been to adjust the assessment upwards  Philip Ziegler, in 1969, estimated the death rate to be at around one third of the population  Jeremy Goldberg, in 1996, believed a number closer to 45 per cent would be more realistic  A 2004 study by Ole Jørgen Benedictow suggests the exceptionally high mortality level of 62 5 per cent  Assuming a population of 6 million, this estimate would correspond to 3,750,000 deaths  Such a high percentage would place England above the average that Benedictow estimates for Western Europe as a whole, of 60 per cent  A death rate at such a high level has not been universally accepted in the historical community In 2016, Carenza Lewis reported the results of a new method of assessing the death toll  She argued that pottery before and after the Black Death is datable because there was a change at that time from the high medieval to the late medieval style, and that counts of pottery of each type therefore provide a useful proxy for long term changes in population  She and her colleagues analysed pottery sherds from test pits in more than 50 continuously occupied rural settlements in eastern England, and found a decline in the number of pottery producing pits of 45 per cent  Norfolk had the greatest drop of 65 per cent, while there was no drop in 10 per cent of settlements, mostly commercial centres 

Impact of the Black Death: 1349
Archbishop Zouche of York issued a warning throughout the diocese in July 1348 (when the epidemic was raging further south) of "great mortalities, pestilences and infections of the air" 
The Great Mortality, as it was then known, entered Yorkshire around February 1349 and quickly spread through the diocese  The clergy were on the front line of the disease, bringing comfort to the dying, hearing final confessions and organising burials  This, almost by necessity, put them at a greater risk of infection 
Estimates suggest that the death rate of clergy in some parts of the archdiocese could have been as high as 48 per cent  This is reflected in the Ordination Register, which shows a massive rise in ordained clergy over the period—some being recruited before the arrival of plague in a clerical recruitment drive, but many once plague had arrived, replacing those who had been killed  In 1346, 111 priests and 337 acolytes were recruited  In 1349, 299 priests and 683 acolytes are named, with 166 priests being ordained in one session alone in February 1350 "

Social distribution
Russell had trusted the IPMs to give a true picture of the national average, because he assumed death rates to be relatively equal across the social spectrum  This assumption has been proven wrong, and studies of peasant plague mortality from manor rolls have returned much higher rates  This could be a consequence of the elite's ability to avoid infection by escaping plague-infected areas  It could also result from lower post-infection mortality among those more affluent, due to better access to care and nursing  If so, this would also mean that the mortality rates for the clergy—who were normally better off than the general population—were no higher than the average 

The manorial records offer a good opportunity to study the geographical distribution of the plague  Its effect seems to have been about the same all over England, though a place like East Anglia, which had frequent contact with the Continent, was severely affected  On a local level, however, there were great variations  A study of the Bishop of Worcester's estates reveal that, while his manors of Hartlebury and Hanbury had a mortality of only 19 per cent, the manor of Aston lost as much as 80 per cent of its population  The manor rolls are less useful for studying the demographic distribution of the mortality, since the rolls only record the heads of households, normally an adult male  Here the IPMs show us that the most vulnerable to the disease were infants and the elderly There seem to have been relatively few deaths from the Black Death at higher levels of society  The only member of the royal family who can be said with any certainty to have died from the Black Death was in France at the time of her infection  Edward III's daughter Joan was residing in Bordeaux on her way to marry Pedro of Castile in the summer of 1348  When the plague broke out in her household she was moved to a small village nearby, but she could not avoid infection, and died there on 2 September  It is possible that the popular religious author Richard Rolle, who died on 30 September 1349, was another victim of the Black Death  The English philosopher William of Ockham has been mentioned as a plague victim  This, however, is an impossibility  Ockham was living in Munich at the time of his death, on 10 April 1347, two years before the Black Death reached that city 

Consequences
Economic, social and political effects
Among the most immediate consequences of the Black Death in England was a shortage of farm labour, and a corresponding rise in wages  The medieval world-view was unable to interpret these changes in terms of socio-economic development, and it became common to blame degrading morals instead  The landowning classes saw the rise in wage levels as a sign of social upheaval and insubordination, and reacted with coercion  In 1349, King Edward III passed the Ordinance of Labourers, fixing wages at pre-plague levels  The ordinance was reinforced by Parliament's passing of the Statute of Labourers in 1351  The labour laws were enforced with ruthless determination over the following decades 

These legislative measures proved largely inefficient at regulating the market, but the government's repressive measures to enforce them caused public resentment  These conditions were contributing factors to the Peasants' Revolt in 1381  The revolt started in Kent and Essex in late May, and once the rebels reached London they burnt down John of Gaunt's Savoy Palace, and killed both the Chancellor and the Treasurer  They then demanded the complete abolition of serfdom, and were not pacified until the young King Richard II personally intervened  The rebellion was eventually suppressed, but the social changes it promoted were already irreversible  By around 1400 serfdom was virtually extinct in England, replaced by the form of tenure called copyhold It is conspicuous how well the English government handled the crisis of the mid-fourteenth century, without descending into chaos and total collapse in the manner of the Valois government of France  To a large extent this was the accomplishment of administrators such as Treasurer William de Shareshull and Chief Justice William Edington, whose highly competent leadership guided the governance of the nation through the crisis  The plague's greatest effect on the government was probably in the field of war, where no major campaigns were launched in France until 1355 Another notable consequence of the Black Death was the raising of the real wage of England (due to the shortage of labour as a result of the reduction in population), a trait shared across Western Europe, which in general led to a real wage in 1450 that was unmatched in most countries until the 19th or 20th century  The higher wages for workers combined with sinking prices on grain products led to a problematic economic situation for the gentry  As a result, they started to show an increased interest for offices like justice of the peace, sheriff and member of parliament  The gentry took advantage of their new positions and a more systematic corruption than before spread  A result of this was that the gentry as a group became highly disliked by commoners 

Religious and cultural consequences
The omnipresence of death also inspired greater piety in the upper classes, which can be seen in the fact that three Cambridge colleges were founded during or shortly after the Black Death  England did not experience the same trend of roving bands of flagellants, common on the continent  Neither were there any pogroms against the Jews, since the Jews had been expelled by Edward I in 1290 The high rate of mortality among the clergy naturally led to a shortage of priests in many parts of the country  The clergy were seen to have an elevated status among ordinary people and this was partly due to their purported closeness with God, being his envoys on earth  However, as the church itself had given the cause of the Black Death to be the impropriety of the behaviour of men, the higher death rate among the clergy led the people to lose faith in the Church as an institution—it had proved as ineffectual against the horror of Y  pestis as every other medieval institution  The corruption within the Catholic priesthood also angered the English people  Many priests abandoned the terrified people  Others sought benefits from the rich families who needed burials  The dissatisfaction led to anti-clericalism and the rise of John Wycliffe, an English priest  His ideas paved a path for the Christian reformation in England  Some people did not lose their Christian faith, if anything it was renewed; they began to long for a more personal relationship with God—around the time after the Black Death many chantries (private chapels) began to spread in use from not just the nobility, but to among the well-to-do  This change in the power of the papacy in England is demonstrated by the statutes of Praemunire 
The Black Death also affected arts and culture significantly  It was inevitable that a catastrophe of such proportions would affect some of the greater building projects, as the amount of available labour fell sharply  The building of the cathedrals of Ely and Exeter was temporarily halted in the years immediately following the first outbreak of the plague  The shortage of labour also helped advance the transition from the Decorated style of building to the less elaborate Perpendicular style  The Black Death may also have promoted the use of vernacular English, as the number of teachers proficient in French dwindled, contributing to the late-14th-century flowering of English literature, represented by writers such as Geoffrey Chaucer and John Gower 

Recurrences
The Black Death was the first occurrence of the second pandemic, which continued to strike England and the rest of Europe more or less regularly until the 18th century  The first serious recurrence in England came in the years 1361−62  Little is known about the death rates caused by these later outbreaks, but the so-called pestis secunda may have had a mortality of around 20 per cent  Genetic analysis performed on remains recovered from the abbey of St  Mary's Graces dating between 1353 and 1364 found the pPCP1 plasmid, a plasmid only found in Yersinia pestis and not the related environmental agent Yersinia pseudotuberculosis, revealing that this outbreak was also caused by Yersinia pestis just as the initial outbreak had been  This epidemic was also particularly devastating for the population's ability to recover, since it disproportionately affected infants and young men  This was also the case with the next occurrence, in 1369, where the death rate was around 10−15 per cent Over the following decades the plague would return—on a national or a regional level—at intervals of five to 12 years, with gradually dwindling death tolls  Then, in the decades from 1430 to 1480, the disease returned in force  An outbreak in 1471 took as much as 10–15 per cent of the population, while the death rate of the plague of 1479–80 could have been as high as 20 per cent  From that point outbreaks became fewer and more manageable, due largely to conscious efforts by central and local governments—from the late 15th century onward—to curtail the disease  This included quarantines on people and goods coming from infected places, bans on public gatherings (such as fairs), enforced household quarantine for the infected (known as 'locking up') and quarantines on ships and crews coming from ports where Plague outbreaks had occurred  From the early seventeenth century there was also greater use of quarantine facilities, called pesthouses, in preference to household quarantine  Some of these, such as the Forlorn Hope Pesthouse established by Bristol in 1665–6, appear to have been proper quarantine hospitals, staffed by doctors  The establishment of such a hospital may help to explain why the death rate in Bristol in the 1665–66 outbreak was "only" c 0 6 percent  This was much lower than the mortality rate of 10–20 percent witnessed in Bristol's Plague epidemics of 1565, 1575, 1603–04 and 1645  The Great Plague of 1665–66 was the last major outbreak in England  It is best known for the famous Great Plague of London, which killed 100,000 people (20 per cent of the population) in the capital  Other places hit hard included Eyam in Derbyshire, Derby itself and Norwich 

See also
Passage 4:
2013 Houphouët-Boigny stampede
The 2013 Houphouët-Boigny stampede occurred as crowds departed a New Year's Eve fireworks display in the early hours of 1 January 2013 near the Félix Houphouët-Boigny Stadium in Abidjan, Ivory Coast  It resulted in 61 deaths and over 200 injuries, mostly women and children  This was the second time in four years that a fatal stampede occurred at the stadium 
President Alassane Ouattara declared three days of mourning and promised an investigation 

Incident
At some time between 1 and 4 am according to sources, following the New Year's Eve celebration and fireworks display, crowds stampeded as they exited the stadium into the Boulevard de la République near the Hotel Tirama  This was the second year that fireworks had been held by the government to commemorate the end of the 2010–2011 Ivorian crisis and the Second Ivorian Civil War, following the controversial 2010 presidential election  According to official reports, 61 individuals were killed, with upwards of 200 injured  According to Alain Lobognon, the Minister of Youth, 26 children were among the dead, most of whom were between the ages of 8 and 15, as well as 28 women and six men 

Investigation and reaction
The cause of the stampede is not yet clear, however a senior police spokesman has confirmed they are investigating  Lieutenant Colonel Issa Sako, the officer in charge of the military responding to the disaster, said that the deaths were caused when "people were walked over and suffocated by the crowd"  According to an Ivorian government official, approximately "50,000 people [were] on the streets     going home" after the New Year's celebrations  Witnesses have alternatively claimed that two large crowds moving in opposite directions collided, and that security forces attempting to break up the crowd leaving the stadium caused a panic Visiting the injured in hospital, President Alassane Ouattara said that the national tragedy would be investigated  Minister of the Interior Hamed Bakayoko stated in a national television broadcast on Radiodiffusion Television Ivoirienne that "the government extends its condolences to the families of those deceased and assures them of its solidarity" and that the Ivorian government would help by "all means possible " Bakayoko went on to say that "the precise circumstances of this tragic occurrence are being looked into by the security services" 
Passage 5:
2010 Elazığ earthquake
The 2010 Elazığ earthquake was a 6 1 Mw earthquake that occurred on 8 March 2010 at 02:32 UTC (04:32 local time)  The epicentre was Başyurt in Elazığ Province, in eastern Turkey  Initial reports in global media said as many as 57 people had died  By 10 March, reports in the Turkish media placed the death toll at 41 and later, the death toll rose to 42  Another 74 were injured, many after falling and jumping from buildings  A stampede through the streets led to further injuries The earthquake came one week to the day after the Turkish Chamber of Civil Engineers sent a report to parliament detailing inadequate building projects and the possibility that Istanbul would be destroyed by an earthquake, which could kill tens of thousands of people, at some point in the next three decades 

Earthquake
The quake occurred on the East Anatolian Fault, a major transform fault which represents  the boundary between the Anatolian Plate and the Arabian Plate 

Damage
According to officials, most of the deaths occurred in three villages: Okçular, Yukarı Kanatlı and Kayalı  At least five villages, though, suffered loss of life  Villagers fled buildings, spending the night outside and lighting fires in the streets for warmth Thirty houses collapsed in Okçular, and the death toll is at least 17  Reports from the scene indicate "the village is totally flattened" and "everything has been knocked down – there is not a stone in place" At least 25 people died in Yukarı Demirci, and emergency services went to Kovancılar Many people used vehicles and taxis to drive to the hospital  Most were asleep at the time the quake struck, with four sleeping sisters perishing in one house  Farm animals were also killed, and minarets fell down 

Aftershocks
Several aftershocks were felt, the strongest measuring 5 5 (at 09:47 local time), 5 1 (at 12:14) and 5 3 (at 13:12)  A total of over 20 aftershocks were counted within a short time following the quake  Villagers were told to stay away from buildings for several days due to the potential of further aftershocks Onur Tan et al  (2011) analyzed 2130 aftershocks (ML≥0 3) and reported in Geophysical Research Letters 

Response
Turkey: Four government ministers, including Deputy Prime Minister Cemil Çiçek, visited the scene as soon as news of the earthquake was reported  The Red Crescent and Turkey's disaster management centre donated blankets and tents  Prime Minister Recep Tayyip Erdoğan later arrived  Pakistan: Prime Minister Yousaf Raza Gillani sent a condolence message to his Turkish counterpart Recep Tayyip Erdoğan over the loss of lives and property and said that "We have learnt with utter sense of shock and profound sadness the news of the massive earthquake that has hit your beautiful country, today  Our hearts go out to our Turkish brethren over the loss of precious lives and destruction of property  I wish to convey, on behalf of the people and Government of Pakistan and on my own behalf our deepest condolences and commiserations to the people and Government of Turkey in bearing this enormous natural calamity " Israel: Defense Minister Ehud Barak ordered an aid proposal to be put together but later said that Turkey informed Israel that it did not require assistance at this time 

See also
2020 Elazığ earthquake
List of earthquakes in 2010
List of earthquakes in Turkey
Passage 6:
Flora (Titian)
Flora is an oil painting by Italian late Renaissance painter Titian, dated to around 1515 and now held at the Uffizi Gallery in Florence 

History
The work was reproduced in numerous 16th century etchings  Later, it followed an unclear series of changes of hands at Brussels and Vienna  In the 17th century, it was sold by the Spanish ambassador at Amsterdam to Archduke Leopold Wilhelm of Austria and was cited by Rembrandt in his Saskia Dressing as Flora  of London and in two portraits in Dresden and New York  Later included in the Kunsthistorisches Museum of Vienna, it was one of the works exchanged with the Uffizi 
In the 18th century, it was erroneously attributed to Palma the Elder 

Description
It portrays an idealized beautiful woman, a model established in the Venetian school by Titian's master Giorgione with his Laura  Her left hand holds a pink-shaded mantle, and her right holds a handful of flowers and leaves 
The woman was portrayed by Titian in numerous other works of the period, including the Woman at the Mirror, the Vanity, Salome and Violante, as well as some Holy Conversations  The meaning of the painting is disputed: some, basing for example to inscriptions added to the 16th century reproductions, identifies the woman as a courtesan; other consider it a symbol of nuptial love, although her dress is not a dressing one  The identification with Flora, the ancient goddess of Spring and vegetation, derives from the presence of Spring flowers in her hands 

See also
List of works by Titian

Notes
Context 3: Passage 1:
Neodymium
Neodymium is a chemical element with the symbol Nd and atomic number 60  It is the fourth member of the lanthanide series and is considered to be one of the rare-earth metals  It is a hard, slightly malleable, silvery metal that quickly tarnishes in air and moisture  When oxidized, neodymium reacts quickly producing pink, purple/blue and yellow compounds in the +2, +3 and +4 oxidation states  It is generally regarded as having one of the most complex spectra of the elements  Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach, who also discovered praseodymium  It is present in significant quantities in the minerals monazite and bastnäsite  Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use  Neodymium is fairly common—about as common as cobalt, nickel, or copper—and is widely distributed in the Earth's crust  Most of the world's commercial neodymium is mined in China, as is the case with many other rare-earth metals 
Neodymium compounds were first commercially used as glass dyes in 1927 and remain a popular additive  The color of neodymium compounds comes from the Nd3+ ion and is often a reddish-purple  However, this changes with the type of lighting because of the interaction of the sharp light absorption bands of neodymium with ambient light enriched with the sharp visible emission bands of mercury, trivalent europium or terbium  Neodymium-doped glasses are used in lasers that emit infrared with wavelengths between 1047 and 1062 nanometers  These lasers have been used in extremely high-power applications, such as experiments in inertial confinement fusion  Neodymium is also used with various other substrate crystals, such as yttrium aluminium garnet in the Nd:YAG laser 
Neodymium alloys are used to make high-strength neodymium magnets—a type of powerful permanent magnet  These magnets are widely used in products like microphones, professional loudspeakers, in-ear headphones, high-performance hobby DC electric motors, and computer hard disks, where low magnet mass (or volume) or strong magnetic fields are required  Larger neodymium magnets are used in electric motors with a high power-to-weight ratio (e g , in hybrid cars) and generators (e g , aircraft and wind turbine electric generators) 

Characteristics
Physical properties
Metallic neodymium has a bright, silvery metallic luster  Neodymium commonly exists in two allotropic forms, with a transformation from a double hexagonal to a body-centered cubic structure taking place at about 863 °C  Neodymium, like most of the lanthanides, is paramagnetic at room temperature and becomes an antiferromagnet upon cooling to 20 K (−253 2 °C)  Neodymium is a rare-earth metal that was present in the classical mischmetal at a concentration of about 18%  To make neodymium magnets it is alloyed with iron, which is a ferromagnet 

Electron configuration
In the periodic table, it appears between the lanthanides praseodymium to its left and the radioactive element promethium to its right, and above the actinide uranium  Its 60 electrons are arranged in the configuration [Xe]4f46s2, of which the six 4f and 6s electrons are valence  Like most other metals in the lanthanide series, neodymium usually only uses three electrons as valence electrons, as afterwards the remaining 4f electrons are strongly bound: this is because the 4f orbitals penetrate the most through the inert xenon core of electrons to the nucleus, followed by 5d and 6s, and this increases with higher ionic charge  Neodymium can still lose a fourth electron because it comes early in the lanthanides, where the nuclear charge is still low enough and the 4f subshell energy high enough to allow the removal of further valence electrons 

Chemical properties
Neodymium is the fourth member of the lanthanide series  It has a melting point of 1,024 °C (1,875 °F) and a boiling point of 3,074 °C (5,565 °F)  Neodymium, like other lanthanides, usually has the oxidation state +3, but it can also form in the +2 and +4 oxidation states, and even, in very rare conditions, +0  Neodymium metal quickly oxidizes at ambient conditions, forming an oxide layer like iron rust that spalls off and exposes the metal to further oxidation; a centimeter-sized sample of neodymium corrodes completely in about a year  Nd3+ is generally soluble in water  Like its neighbor praseodymium, it readily burns at about 150 °C to form neodymium(III) oxide; the oxide peels off, exposing the bulk metal to the further oxidation:
4Nd + 3O2 → 2Nd2O3Neodymium is a quite electropositive element, and it reacts slowly with cold water, or quickly with hot water, to form neodymium(III) hydroxide:

2Nd (s) + 6H2O (l) → 2Nd(OH)3 (aq) + 3H2 (g)Neodymium metal reacts vigorously with all the stable halogens:
2Nd (s) + 3F2 (g) → 2NdF3 (s) [a violet substance]
2Nd (s) + 3Cl2 (g) → 2NdCl3 (s) [a mauve substance]
2Nd (s) + 3Br2 (g) → 2NdBr3 (s) [a violet substance]
2Nd (s) + 3I2 (g) → 2NdI3 (s) [a green substance]Neodymium dissolves readily in dilute sulfuric acid to form solutions that contain the lilac Nd(III) ion  These exist as a [Nd(OH2)9]3+ complexes:
2Nd (s) + 3H2SO4 (aq) → 2Nd3+ (aq) + 3SO2−4 (aq) + 3H2 (g)

Compounds
Some of the most important neodymium compounds include:

halides: NdF3; NdCl2; NdCl3; NdBr3; NdI2; NdI3
oxides: Nd2O3
hydroxide: Nd(OH)3
carbonate: Nd2(CO3)3
sulfate: Nd2(SO4)3
acetate: Nd(CH3COO)3
neodymium magnets (Nd2Fe14B)Some neodymium compounds have colors that vary based on the type of lighting 

Organoneodymium compounds
Organoneodymium compounds are compounds that have a neodymium–carbon bond  These compounds are similar to those of the other lanthanides, characterized by an inability to undergo π backbonding  They are thus mostly restricted to the mostly ionic cyclopentadienides (isostructural with those of lanthanum) and the σ-bonded simple alkyls and aryls, some of which may be polymeric 

Isotopes
Naturally occurring neodymium (60Nd) is composed of five stable isotopes—142Nd, 143Nd, 145Nd, 146Nd and 148Nd, with 142Nd being the most abundant (27 2% of the natural abundance)—and two radioisotopes with extremely long half-lives, 144Nd (alpha decay with a half-life (t1/2) of 2 29×1015 years) and 150Nd (double beta decay, t1/2 ≈ 7×1018 years)  In all, 33 radioisotopes of neodymium have been detected as of 2022, with the most stable radioisotopes being the naturally occurring ones: 144Nd and 150Nd  All of the remaining radioactive isotopes have half-lives that are shorter than twelve days, and the majority of these have half-lives that are shorter than 70 seconds; the most stable artificial isotope is 147Nd with a half-life of 10 98 days 
Neodymium also has 13 known metastable isotopes, with the most stable one being 139mNd (t1/2 = 5 5 hours), 135mNd (t1/2 = 5 5 minutes) and 133m1Nd (t1/2 ~70 seconds)  The primary decay modes before the most abundant stable isotope, 142Nd, are electron capture and positron decay, and the primary mode after is beta minus decay  The primary decay products before 142Nd are element Pr (praseodymium) isotopes and the primary products after are element Pm (promethium) isotopes  Four of the five stable isotopes have been predicted to decay to isotopes of cerium or samarium and are only observationally stable  Additionally, some observationally stable isotopes of samarium are predicted to decay to isotopes of neodymium Neodymium isotopes are used in various scientific applications  142Nd has been used for the production of short-lived Tm and Yb isotopes  146Nd has been suggested for the production of 147Pm, which is a source of radioactive power  Several neodymium isotopes have been used for the production of other promethium isotopes  The decay from 147Sm (t1/2 = 1 06×1011 y) to the stable 143Nd allows samarium–neodymium dating  150Nd has also been used to study double beta decay 

History
In 1751, the Swedish mineralogist Axel Fredrik Cronstedt discovered a heavy mineral from the mine at Bastnäs, later named cerite  Thirty years later, fifteen-year-old Wilhelm Hisinger, a member of the family owning the mine, sent a sample to Carl Scheele, who did not find any new elements within  In 1803, after Hisinger had become an ironmaster, he returned to the mineral with Jöns Jacob Berzelius and isolated a new oxide, which they named ceria after the dwarf planet Ceres, which had been discovered two years earlier  Ceria was simultaneously and independently isolated in Germany by Martin Heinrich Klaproth  Between 1839 and 1843, ceria was shown to be a mixture of oxides by the Swedish surgeon and chemist Carl Gustaf Mosander, who lived in the same house as Berzelius; he separated out two other oxides, which he named lanthana and didymia  He partially decomposed a sample of cerium nitrate by roasting it in air and then treating the resulting oxide with dilute nitric acid  The metals that formed these oxides were thus named lanthanum and didymium, officially discovered in Vienna in 1885 by Carl Gustaf Mosander  Von Welsbach confirmed the separation by spectroscopic analysis, but the products were of relatively low purity  Didymium was discovered by Carl Gustaf Mosander in 1841, and pure neodymium was isolated from it in 1925  The name neodymium is derived from the Greek words neos (νέος), new, and didymos (διδύμος), twin Double nitrate crystallization was the means of commercial neodymium purification until the 1950s  Lindsay Chemical Division was the first to commercialize large-scale ion-exchange purification of neodymium  Starting in the 1950s, high purity (>99%) neodymium was primarily obtained through an ion exchange process from monazite, a mineral rich in rare-earth elements  The metal is obtained through electrolysis of its halide salts  Currently, most neodymium is extracted from bastnäsite and purified by solvent extraction  Ion-exchange purification is used for the highest purities (typically >99 99%)  The evolving technology, and improved purity of commercially available neodymium oxide, was reflected in the appearance of neodymium glasses in collections today  Early neodymium glasses made in the 1930s have a more reddish or orange tinge than modern versions, which are more cleanly purple, because of the difficulties in removing traces of praseodymium using early technology, namely fractional crystallization Because of its role in permanent magnets used for direct-drive wind turbines, it has been argued that neodymium will be one of the main objects of geopolitical competition in a world running on renewable energy  This perspective has been criticised for failing to recognise that most wind turbines do not use permanent magnets, and for underestimating the power of economic incentives for expanded production 

Occurrence and production
Occurrence
Neodymium is rarely found in nature as a free element, instead occurring as ores, such as monazite and bastnäsite (these are mineral group names rather than single mineral names) that contain small amounts of all rare-earth metals  In these minerals neodymium is rarely dominant; some exceptions include monazite-(Nd) and kozoite-(Nd)  The main mining areas are in China, United States, Brazil, India, Sri Lanka, and Australia  World reserves of neodymium are estimated at eight million tonnes The Nd3+ ion is similar in size to the early lanthanides of the cerium group (those from lanthanum up to samarium and europium) that immediately follow in the periodic table, and hence it tends to occur along with them in phosphate, silicate and carbonate minerals, such as monazite (MIIIPO4) and bastnäsite (MIIICO3F), where M refers to all the rare-earth metals except scandium and the radioactive promethium (mostly Ce, La, and Y, with somewhat less Pr and Nd)  Bastnäsite is usually lacking in thorium and the heavy lanthanides, and the purification of the light lanthanides from it is less involved  The ore, after being crushed and ground, is first treated with hot concentrated sulfuric acid, evolving carbon dioxide, hydrogen fluoride, and silicon tetrafluoride  The product is then dried and leached with water, leaving the early lanthanide ions, including lanthanum, in solution 

In space
Neodymium's per-particle abundance in the Solar System is 0 083 ppb (parts per billion)  This figure is about two thirds of that of platinum, but two and a half times more than mercury, and nearly five times more than gold  The lanthanides are not usually found in space, and are much more abundant in the Earth's crust 

In the Earth's crust
Neodymium is classified as a lithophile under the Goldschmidt classification, meaning that it is generally found combined with oxygen  Although it belongs to the rare-earth metals, neodymium is not rare at all  Its abundance in the Earth's crust is about 38 mg/kg, making it the 27th most common element  It is similar in abundance to lanthanum  Cerium is the most common rare-earth metal, followed by neodymium, and then lanthanum 

Production
The world's production of neodymium was about 7,000 tons in 2004  The bulk of current production is from China  Historically, the Chinese government imposed strategic material controls on the element, causing large fluctuations in prices  The uncertainty of pricing and availability have caused companies (particularly Japanese ones) to create permanent magnets and associated electric motors with fewer rare-earth metals; however, so far they have been unable to eliminate the need for neodymium  According to the US Geological Survey, Greenland holds the largest reserves of undeveloped rare-earth deposits, particularly neodymium  Mining interests clash with native populations at those sites, due to the release of radioactive substances during the mining process 

Neodymium is typically 10–18% of the rare-earth content of commercial deposits of the light rare-earth-element minerals bastnäsite and monazite  With neodymium compounds being the most strongly colored for the trivalent lanthanides, it can occasionally dominate the coloration of rare-earth minerals when competing chromophores are absent  It usually gives a pink coloration  Outstanding examples of this include monazite crystals from the tin deposits in Llallagua, Bolivia; ancylite from Mont Saint-Hilaire, Quebec, Canada; or lanthanite from the Saucon Valley, Pennsylvania, United States  As with neodymium glasses, such minerals change their colors under the differing lighting conditions  The absorption bands of neodymium interact with the visible emission spectrum of mercury vapor, with the unfiltered shortwave UV light causing neodymium-containing minerals to reflect a distinctive green color  This can be observed with monazite-containing sands or bastnäsite-containing ore The demand for mineral resources, such as rare-earth elements (including neodymium) and other critical materials, has been rapidly increasing owing to the growing human population and industrial development  Recently, the requirement for a low-carbon society has led to a significant demand for energy-saving technologies such as batteries, high-efficiency motors, renewable energy sources, and fuel cells  Among these technologies, permanent magnets are often used to fabricate high-efficiency motors, with neodymium-iron-boron magnets (Nd2Fe14B sintered and bonded magnets; hereinafter referred to as NdFeB magnets) being the main type of permanent magnet in the market since their invention  NdFeB magnets are used in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), electric vehicles (EVs), and fuel cell vehicles (FCVs) (hereinafter referred to as xEVs), wind turbines, home appliances, computers, and many small consumer electronic devices  Furthermore, they are indispensable for energy savings  Toward achieving the objectives of the Paris Agreement, the demand for NdFeB magnets is expected to increase significantly in the future 

Applications
Neodymium has an unusually large specific heat capacity at liquid-helium temperatures, so is useful in cryocoolers 
Neodymium acetate can be a substitute for the radioactive and toxic uranyl acetate (used as a standard contrasting agent in electron microscopy) 
Probably because of similarities to Ca2+, Nd3+ has been reported to promote plant growth  Rare-earth element compounds are frequently used in China as fertilizer 
Samarium–neodymium dating is useful for determining the age relationships of rocks  and meteorites
Neodymium isotopes recorded in marine sediments are used to reconstruct changes in past ocean circulation 

Magnets
Neodymium magnets (an alloy, Nd2Fe14B) are the strongest permanent magnets known  A neodymium magnet of a few tens of grams can lift a thousand times its own weight, and can snap together with enough force to break bones  These magnets are cheaper, lighter, and stronger than samarium–cobalt magnets  However, they are not superior in every aspect, as neodymium-based magnets lose their magnetism at lower temperatures and tend to corrode, while samarium–cobalt magnets do not Neodymium magnets appear in products such as microphones, professional loudspeakers, headphones, guitar and bass guitar pick-ups, and computer hard disks where low mass, small volume, or strong magnetic fields are required  Neodymium is used in the electric motors of hybrid and electric automobiles and in the electricity generators of some designs of commercial wind turbines (only wind turbines with "permanent magnet" generators use neodymium)  For example, drive electric motors of each Toyota Prius require one kilogram (2 2 pounds) of neodymium per vehicle In 2020, physics researchers at Radboud University and Uppsala University announced they had observed a behavior known as "self-induced spin glass" in the atomic structure of neodymium  One of the researchers explained, "…we are specialists in scanning tunneling microscopy  It allows us to see the structure of individual atoms, and we can resolve the north and south poles of the atoms  With this advancement in high-precision imaging, we were able to discover the behavior in neodymium, because we could resolve the incredibly small changes in the magnetic structure "  Neodymium behaves in a complex magnetic way that had not been seen before in a periodic table element 

Glass
Neodymium glass (Nd:glass) is produced by the inclusion of neodymium oxide (Nd2O3) in the glass melt  Usually in daylight or incandescent light neodymium glass appears lavender, but it appears pale blue under fluorescent lighting  Neodymium may be used to color glass in delicate shades ranging from pure violet through wine-red and warm gray The first commercial use of purified neodymium was in glass coloration, starting with experiments by Leo Moser in November 1927  The resulting "Alexandrite" glass remains a signature color of the Moser glassworks to this day  Neodymium glass was widely emulated in the early 1930s by American glasshouses, most notably Heisey, Fostoria ("wisteria"), Cambridge ("heatherbloom"), and Steuben ("wisteria"), and elsewhere (e g  Lalique, in France, or Murano)  Tiffin's "twilight" remained in production from about 1950 to 1980  Current sources include glassmakers in the Czech Republic, the United States, and China The sharp absorption bands of neodymium cause the glass color to change under different lighting conditions, being reddish-purple under daylight or yellow incandescent light, but blue under white fluorescent lighting, or greenish under trichromatic lighting  This color-change phenomenon is highly prized by collectors  In combination with gold or selenium, red colors are produced  Since neodymium coloration depends upon "forbidden" f-f transitions deep within the atom, there is relatively little influence on the color from the chemical environment, so the color is impervious to the thermal history of the glass  However, for the best color, iron-containing impurities need to be minimized in the silica used to make the glass  The same forbidden nature of the f-f transitions makes rare-earth colorants less intense than those provided by most d-transition elements, so more has to be used in a glass to achieve the desired color intensity  The original Moser recipe used about 5% of neodymium oxide in the glass melt, a sufficient quantity such that Moser referred to these as being "rare-earth doped" glasses  Being a strong base, that level of neodymium would have affected the melting properties of the glass, and the lime content of the glass might have had to be adjusted accordingly Light transmitted through neodymium glasses shows unusually sharp absorption bands; the glass is used in astronomical work to produce sharp bands by which spectral lines may be calibrated  Another application is the creation of selective astronomical filters to reduce the effect of light pollution from sodium and fluorescent lighting while passing other colours, especially dark red hydrogen-alpha emission from nebulae  Neodymium is also used to remove the green color caused by iron contaminants from glass 

Neodymium is a component of "didymium" (referring to mixture of salts of neodymium and praseodymium) used for coloring glass to make welder's and glass-blower's goggles; the sharp absorption bands obliterate the strong sodium emission at 589 nm  The similar absorption of the yellow mercury emission line at 578 nm is the principal cause of the blue color observed for neodymium glass under traditional white-fluorescent lighting  Neodymium and didymium glass are used in color-enhancing filters in indoor photography, particularly in filtering out the yellow hues from incandescent lighting  Similarly, neodymium glass is becoming widely used more directly in incandescent light bulbs  These lamps contain neodymium in the glass to filter out yellow light, resulting in a whiter light which is more like sunlight  During World War I, didymium mirrors were reportedly used to transmit Morse Code across battlefields  Similar to its use in glasses, neodymium salts are used as a colorant for enamels 

Lasers
Certain transparent materials with a small concentration of neodymium ions can be used in lasers as gain media for infrared wavelengths (1054–1064 nm), e g  Nd:YAG (yttrium aluminium garnet), Nd:YAP (yttrium aluminium perovskite), Nd:YLF (yttrium lithium fluoride), Nd:YVO4 (yttrium orthovanadate), and Nd:glass  Neodymium-doped crystals (typically Nd:YVO4) generate high-powered infrared laser beams which are converted to green laser light in commercial DPSS hand-held lasers and laser pointers 

Trivalent neodymium ion Nd3+ was the first lanthanide from rare-earth elements used for the generation of laser radiation  The Nd:CaWO4 laser was developed in 1961  Historically, it was the third laser which was put into operation (the first was ruby, the second the U3+:CaF laser)  Over the years the neodymium laser became one of the most used lasers for application purposes  The success of the Nd3+ ion lies in the structure of its energy levels and in the spectroscopic properties suitable for the generation of laser radiation  In 1964 Geusic et al  demonstrated the operation of neodymium ion in YAG matrix Y3Al5O12  It is a four-level laser with lower threshold and with excellent mechanical and temperature properties  For optical pumping of this material it is possible to use non-coherent flashlamp radiation or a coherent diode beam 

The current laser at the UK Atomic Weapons Establishment (AWE), the HELEN (High Energy Laser Embodying Neodymium) 1-terawatt neodymium-glass laser, can access the midpoints of pressure and temperature regions and is used to acquire data for modeling on how density, temperature, and pressure interact inside warheads  HELEN can create plasmas of around 106 K, from which opacity and transmission of radiation are measured Neodymium glass solid-state lasers are used in extremely high power (terawatt scale), high energy (megajoules) multiple beam systems for inertial confinement fusion  Nd:glass lasers are usually frequency tripled to the third harmonic at 351 nm in laser fusion devices 

Substitute for uranyl acetate
Uranyl acetate has been the standard contrasting agent in transmission electron microscopy (TEM) for decades  However, its use is increasingly hampered by regulations by governments due to its radioactive properties as well as its high toxicity  Therefore, alternatives are being searched for, including lanthanide acetates or platinum blue  as well as the use of less defined substances such as oolong tea extract  Despite these published alternatives, uranyl acetate (UAc) is still the standard for EM contrasting In the periodic table the vertical ordering of elements in groups is based on the presence of the same number of electrons in their outermost shell, which determines their chemical and physical properties  Because neodymium (Nd) is right above uranium (U) the chemical properties of UAc and NdAc would be very similar in binding to tissue in ultrathin sections thus leading to a similar amount of contrast 

Biological role and precautions
The early lanthanides have been found to be essential to some methanotrophic bacteria living in volcanic mudpots, such as Methylacidiphilum fumariolicum: lanthanum, cerium, praseodymium, and neodymium are about equally effective  Neodymium is otherwise not known to have a biological role in any other organisms Neodymium metal dust is combustible and therefore an explosion hazard  Neodymium compounds, as with all rare-earth metals, are of low to moderate toxicity; however, its toxicity has not been thoroughly investigated  Neodymium salts are regarded as more toxic if they are soluble than if they are insoluble if they are ingested  Neodymium dust and salts are very irritating to the eyes and mucous membranes, and moderately irritating to skin  Breathing the dust can cause lung embolisms, and accumulated exposure damages the liver  Neodymium also acts as an anticoagulant, especially when given intravenously Neodymium magnets have been tested for medical uses such as magnetic braces and bone repair, but biocompatibility issues have prevented widespread application  Commercially available magnets made from neodymium are exceptionally strong and can attract each other from large distances  If not handled carefully, they come together very quickly and forcefully, causing injuries  For example, there is at least one documented case of a person losing a fingertip when two magnets he was using snapped together from 50 cm away Another risk of these powerful magnets is that if more than one magnet is ingested, they can pinch soft tissues in the gastrointestinal tract  This has led to an estimated 1,700 emergency room visits and necessitated the recall of the Buckyballs line of toys, which were construction sets of small neodymium magnets 

See also
Neodymium compounds
Category:Neodymium compounds
Lanthanides
Period 6 elements
Rare earth metals

Notes
Passage 2:
James Chadwick
Sir James Chadwick,  (20 October 1891 – 24 July 1974) was a British physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932  In 1941, he wrote the final draft of the MAUD Report, which inspired the U S  government to begin serious atom bomb research efforts  He was the head of the British team that worked on the Manhattan Project during World War II  He was knighted in Britain in 1945 for his achievements in physics 
Chadwick graduated from the Victoria University of Manchester in 1911, where he studied under Ernest Rutherford (known as the "father of nuclear physics")  At Manchester, he continued to study under Rutherford until he was awarded his MSc in 1913  The same year, Chadwick was awarded an 1851 Research Fellowship from the Royal Commission for the Exhibition of 1851  He elected to study beta radiation under Hans Geiger in Berlin  Using Geiger's recently developed Geiger counter, Chadwick was able to demonstrate that beta radiation produced a continuous spectrum, and not discrete lines as had been thought  Still in Germany when World War I broke out in Europe, he spent the next four years in the Ruhleben internment camp 
After the war, Chadwick followed Rutherford to the Cavendish Laboratory at the University of Cambridge, where Chadwick earned his Doctor of Philosophy degree under Rutherford's supervision from Gonville and Caius College, Cambridge, in June 1921  He was Rutherford's assistant director of research at the Cavendish Laboratory for over a decade at a time when it was one of the world's foremost centres for the study of physics, attracting students like John Cockcroft, Norman Feather, and Mark Oliphant  Chadwick followed his discovery of the neutron by measuring its mass  He anticipated that neutrons would become a major weapon in the fight against cancer  Chadwick left the Cavendish Laboratory in 1935 to become a professor of physics at the University of Liverpool, where he overhauled an antiquated laboratory and, by installing a cyclotron, made it an important centre for the study of nuclear physics 
During the Second World War, Chadwick carried out research as part of the Tube Alloys project to build an atom bomb, while his Manchester lab and environs were harassed by Luftwaffe bombing  When the Quebec Agreement merged his project with the American Manhattan Project, he became part of the British Mission, and worked at the Los Alamos Laboratory and in Washington, D C  He surprised everyone by earning the almost-complete trust of project director Leslie R  Groves, Jr  For his efforts, Chadwick received a knighthood in the New Year Honours on 1 January 1945  In July 1945, he viewed the Trinity nuclear test  After this, he served as the British scientific advisor to the United Nations Atomic Energy Commission  Uncomfortable with the trend toward Big Science, he became the Master of Gonville and Caius College in 1948  He retired in 1959 

Education and early life
James Chadwick was born in Bollington, Cheshire, on 20 October 1891, the first child of John Joseph Chadwick, a cotton spinner, and Anne Mary Knowles, a domestic servant  He was named James after his paternal grandfather  In 1895, his parents moved to Manchester, leaving him in the care of his maternal grandparents  He went to Bollington Cross Primary School, and was offered a scholarship to Manchester Grammar School, which his family had to turn down as they could not afford the small fees that still had to be paid  Instead he attended the Central Grammar School for Boys in Manchester, rejoining his parents there  He now had two younger brothers, Harry and Hubert; a sister had died in infancy  At the age of 16, he sat two examinations for university scholarships, and won both of them Chadwick chose to attend Victoria University of Manchester, which he entered in 1908  He meant to study mathematics, but enrolled in physics by mistake  Like most students, he lived at home, walking the 4 miles (6 4 km) to the university and back each day  At the end of his first year, he was awarded a Heginbottom Scholarship to study physics  The physics department was headed by Ernest Rutherford, who assigned research projects to final-year students, and he instructed Chadwick to devise a means of comparing the amount of radioactive energy of two different sources  The idea was that they could be measured in terms of the activity of 1 gram (0 035 oz) of radium, a unit of measurement which would become known as the curie  Rutherford's suggested approach was unworkable—something Chadwick knew but was afraid to tell Rutherford—so Chadwick pressed on, and eventually devised the required method  The results became Chadwick's first paper, which, co-authored with Rutherford, was published in 1912  He graduated with first class honours in 1911 Having devised a means of measuring gamma radiation, Chadwick proceeded to measure the absorption of gamma rays by various gases and liquids  This time the resulting paper was published under his name alone  He was awarded his Master of Science (MSc) degree in 1912, and was appointed a Beyer Fellow  The following year he was awarded an 1851 Exhibition Scholarship, which allowed him to study and research at a university in continental Europe  He elected to go to the Physikalisch-Technische Reichsanstalt in Berlin in 1913, to study beta radiation under Hans Geiger  Using Geiger's recently developed Geiger counter, which provided more accuracy than the earlier photographic techniques, he was able to demonstrate that beta radiation did not produce discrete lines, as has been previously thought, but rather a continuous spectrum with peaks in certain regions  On a visit to Geiger's laboratory, Albert Einstein told Chadwick that: "I can explain either of these things, but I can't explain them both at the same time " The continuous spectrum would remain an unexplained phenomenon for many years Chadwick was still in Germany at the start of the First World War, and was interned in the Ruhleben internment camp near Berlin, where he was allowed to set up a laboratory in the stables and conduct scientific experiments using improvised materials such as radioactive toothpaste  With the help of Charles Drummond Ellis, he worked on the ionisation of phosphorus, and the photochemical reaction of carbon monoxide and chlorine  He was released after the Armistice with Germany came into effect in November 1918, and returned to his parents' home in Manchester, where he wrote up his findings over the previous four years for the 1851 Exhibition commissioners Rutherford gave Chadwick a part-time teaching position at Manchester, allowing him to continue research  He looked at the nuclear charge of platinum, silver, and copper, and experimentally found that this was the same as the atomic number within an error of less than 1 5 per cent  In April 1919, Rutherford became director of the Cavendish Laboratory at the University of Cambridge, and Chadwick joined him there a few months later  Chadwick was awarded a Clerk-Maxwell studentship in 1920, and enrolled as a Doctor of Philosophy (PhD) student at Gonville and Caius College, Cambridge  The first half of his thesis was his work with atomic numbers  In the second, he looked at the forces inside the nucleus  His degree was awarded in June 1921  In November, he became a Fellow of Gonville and Caius College 

Researcher
Cambridge
Chadwick's Clerk-Maxwell studentship expired in 1923, and he was succeeded by the Russian physicist Pyotr Kapitza  The Chairman of the Advisory Council of the Department of Scientific and Industrial Research, Sir William McCormick arranged for Chadwick to become Rutherford's assistant director of research  In this role, Chadwick helped Rutherford select PhD students  Over the next few years these would include John Cockcroft, Norman Feather and Mark Oliphant, who would become firm friends with Chadwick  As many students had no idea what they wanted to research, Rutherford and Chadwick would suggest topics  Chadwick edited all the papers produced by the laboratory 

In 1925, Chadwick met Aileen Stewart-Brown, the daughter of a Liverpool stockbroker  The two were married in August 1925, with Kapitza as Best Man  The couple had twin daughters, Joanna and Judith, who were born in February 1927 In his research, Chadwick continued to probe the nucleus  In 1925, the concept of spin had allowed physicists to explain the Zeeman effect, but it also created unexplained anomalies  At the time it was believed that the nucleus consisted of protons and electrons, so nitrogen's nucleus, for example, with a mass number of 14, was assumed to contain 14 protons and 7 electrons  This gave it the right mass and charge, but the wrong spin At a conference at Cambridge on beta particles and gamma rays in 1928, Chadwick met Geiger again  Geiger had brought with him a new model of his Geiger counter, which had been improved by his post-doctoral student Walther Müller  Chadwick had not used one since the war, and the new Geiger–Müller counter was potentially a major improvement over the scintillation techniques then in use at Cambridge, which relied on the human eye for observation  The major drawback with it was that it detected alpha, beta and gamma radiation, and radium, which the Cavendish laboratory normally used in its experiments, emitted all three, and was therefore unsuitable for what Chadwick had in mind  However, polonium is an alpha emitter, and Lise Meitner sent Chadwick about 2 millicuries (about 0 5 μg) from Germany In Germany, Walther Bothe and his student Herbert Becker had used polonium to bombard beryllium with alpha particles, producing an unusual form of radiation  Chadwick had his Australian 1851 Exhibition scholar, Hugh Webster, duplicate their results  To Chadwick, this was evidence of something that he and Rutherford had been hypothesising for years: the neutron, a theoretical nuclear particle with no electric charge  Then in January 1932, Feather drew Chadwick's attention to another surprising result  Frédéric and Irène Joliot-Curie had succeeded in knocking protons from paraffin wax using polonium and beryllium as a source for what they thought was gamma radiation  Rutherford and Chadwick disagreed; protons were too heavy for that  But neutrons would need only a small amount of energy to achieve the same effect  In Rome, Ettore Majorana came to the same conclusion: the Joliot-Curies had discovered the neutron but did not know it 

Chadwick dropped all his other responsibilities to concentrate on proving the existence of the neutron, assisted by Feather and frequently working late at night  He devised a simple apparatus that consisted of a cylinder containing a polonium source and beryllium target  The resulting radiation could then be directed at a material such as paraffin wax; the displaced particles, which were protons, would go into a small ionisation chamber where they could be detected with an oscilloscope 
In February 1932, after only about two weeks of experimentation with neutrons, Chadwick sent a letter to Nature titled "Possible Existence of a Neutron"  He communicated his findings in detail in an article sent to Proceedings of the Royal Society A titled "The Existence of a Neutron" in May  His discovery of the neutron was a milestone in understanding the nucleus  Reading Chadwick's paper, Robert Bacher and Edward Condon realised that anomalies in the then-current theory, like the spin of nitrogen, would be resolved if the neutron has a spin of 1/2 and that a nitrogen nucleus consisted of seven protons and seven neutrons The theoretical physicists Niels Bohr and Werner Heisenberg considered whether the neutron could be a fundamental nuclear particle like the proton and electron, rather than a proton–electron pair   Heisenberg showed that the neutron was best described as a new nuclear particle, but its exact nature remained unclear   In his 1933 Bakerian Lecture, Chadwick estimated that a neutron had a mass of about 1 0067 u  Since a proton and an electron had a combined mass of 1 0078 u, this implied the neutron as a proton–electron composite had a binding energy of about 2 MeV, which sounded reasonable, although it was hard to understand how a particle with so little binding energy could be stable   Estimating such a small mass difference required challenging precise measurements, however, and several conflicting results were obtained in 1933–4   By bombarding boron with alpha particles, Frédéric and Irène Joliot-Curie obtained a large value for the mass of a neutron, but Ernest Lawrence's team at the University of California produced a small one   Then Maurice Goldhaber, a refugee from Nazi Germany and a graduate student at the Cavendish Laboratory, suggested to Chadwick that deuterons could be photodisintegrated by the 2 6 MeV gamma rays of 208Tl (then known as thorium C"):

An accurate value for the mass of the neutron could be determined from this process  Chadwick and Goldhaber tried this and found that it worked   They measured the kinetic energy of the proton produced as 1 05 MeV, leaving the mass of the neutron as the unknown in the equation   Chadwick and Goldhaber calculated that it was either 1 0084 or 1 0090 atomic units, depending on the values used for the masses of the proton and deuteron   (The modern accepted value for the mass of the neutron is 1 00866 u ) The mass of the neutron was too large to be a proton–electron pair For his discovery of the neutron, Chadwick was awarded the Hughes Medal by the Royal Society in 1932, the Nobel Prize in Physics in 1935, the Copley Medal in 1950 and the Franklin Medal in 1951  His discovery of the neutron made it possible to produce elements heavier than uranium in the laboratory by the capture of slow neutrons followed by beta decay  Unlike the positively charged alpha particles, which are repelled by the electrical forces present in the nuclei of other atoms, neutrons do not need to overcome any Coulomb barrier, and can therefore penetrate and enter the nuclei of even the heaviest elements such as uranium  This inspired Enrico Fermi to investigate the nuclear reactions brought about by collisions of nuclei with slow neutrons, work for which Fermi would receive the Nobel Prize in 1938 Wolfgang Pauli proposed another kind of particle on 4 December 1930 in order to explain the continuous spectrum of beta radiation that Chadwick had reported in 1914  Since not all of the energy of beta radiation could be accounted for, the law of conservation of energy appeared to be violated, but Pauli argued that this could be redressed if another, undiscovered, particle was involved  Pauli also called this particle a neutron, but it was clearly not the same particle as Chadwick's neutron  Fermi renamed it the neutrino, Italian for "little neutron"  In 1934, Fermi proposed his theory of beta decay which explained that the electrons emitted from the nucleus were created by the decay of a neutron into a proton, an electron, and a neutrino   The neutrino could account for the missing energy, but a particle with little mass and no electric charge was difficult to observe  Rudolf Peierls and Hans Bethe calculated that neutrinos could easily pass through the Earth, so the chances of detecting them were slim  Frederick Reines and Clyde Cowan would confirm the neutrino on 14 June 1956 by placing a detector within a large antineutrino flux from a nearby nuclear reactor 

Liverpool
With the onset of the Great Depression in the United Kingdom, the government became more parsimonious with funding for science  At the same time, Lawrence's recent invention, the cyclotron, promised to revolutionise experimental nuclear physics, and Chadwick felt that the Cavendish laboratory would fall behind unless it also acquired one  He therefore chafed under Rutherford, who clung to the belief that good nuclear physics could still be done without large, expensive equipment, and turned down the request for a cyclotron 

Chadwick was himself a critic of Big Science in general, and Lawrence in particular, whose approach he considered careless and focused on technology at the expense of science  When Lawrence postulated the existence of a new and hitherto unknown particle that he claimed was a possible source of limitless energy at the Solvay Conference in 1933, Chadwick responded that the results were more likely attributable to contamination of the equipment  While Lawrence rechecked his results at Berkeley only to find that Chadwick was correct, Rutherford and Oliphant conducted an investigation at the Cavendish that found that deuterium fuses to form helium-3, thereby causing the effect that Lawrence had observed  This was another major discovery, but the Oliphant-Rutherford particle accelerator was an expensive state-of-the-art piece of equipment In March 1935, Chadwick received an offer of the Lyon Jones Chair of physics at the University of Liverpool, in his wife's home town, to succeed Lionel Wilberforce  The laboratory was so antiquated that it still ran on direct current electricity, but Chadwick seized the opportunity, assuming the chair on 1 October 1935  The university's prestige was soon bolstered by Chadwick's Nobel Prize, which was announced in November 1935  His medal was sold at auction in 2014 for $329,000 Chadwick set about acquiring a cyclotron for Liverpool  He started by spending £700 to refurbish the antiquated laboratories at Liverpool, so some components could be made in-house  He was able to persuade the university to provide £2,000 and obtained a grant for another £2,000 from the Royal Society  To build his cyclotron, Chadwick brought in two young experts, Bernard Kinsey and Harold Walke, who had worked with Lawrence at the University of California  A local cable manufacturer donated the copper conductor for the coils  The cyclotron's 50-ton magnet was manufactured in Trafford Park by Metropolitan-Vickers, which also made the vacuum chamber  The cyclotron was completely installed and running in July 1939  The total cost of £5,184 was more than Chadwick had received from the University and the Royal Society, so Chadwick paid the rest from his 159,917 kr (£8,243) Nobel Prize money At Liverpool the Medicine and Science faculties worked together closely  Chadwick was automatically a committee member of both faculties, and in 1938 he was appointed to a commission headed by Lord Derby to investigate the arrangements for cancer treatment in Liverpool  Chadwick anticipated that neutrons and radioactive isotopes produced with the 37-inch cyclotron could be used to study biochemical processes, and might become a weapon in the fight against cancer 

Second World War
Tube Alloys and the MAUD Report
In Germany, Otto Hahn and Fritz Strassmann bombarded uranium with neutrons, and noted that barium, a lighter element, was among the products produced  Hitherto, only the same or heavier elements had been produced by the process  In January 1939, Meitner and her nephew Otto Frisch astounded the physics community with a paper that explained this result  They theorised that uranium atoms bombarded with neutrons can break into two roughly equal fragments, a process they called fission  They calculated that this would result in the release of about 200 MeV, implying an energy release orders of magnitude greater than chemical reactions, and Frisch confirmed their theory experimentally  It was soon noted by Hahn that if neutrons were released during fission, then a chain reaction was possible  French scientists, Pierre Joliot, Hans von Halban and Lew Kowarski, soon verified that more than one neutron was indeed emitted per fission  In a paper co-authored with the American physicist John Wheeler, Bohr theorised that fission was more likely to occur in the uranium-235 isotope, which made up only 0 7 percent of natural uranium 

Chadwick did not believe that there was any likelihood of another war with Germany in 1939, and took his family for a holiday on a remote lake in northern Sweden  The news of the outbreak of the Second World War therefore came as a shock  Determined not to spend another war in an internment camp, Chadwick made his way to Stockholm as fast as he could, but when he arrived there with his family, he found that all air traffic between Stockholm and London had been suspended  They made their way back to England on a tramp steamer  When he reached Liverpool, Chadwick found Joseph Rotblat, a Polish post-doctoral fellow who had come to work with the cyclotron, was now destitute, as he was cut off from funds from Poland  Chadwick promptly hired Rotblat as a lecturer, despite his poor grasp of English In October 1939, Chadwick received a letter from Sir Edward Appleton, the Secretary of the Department of Scientific and Industrial Research, asking for his opinion on the feasibility of an atom bomb  Chadwick responded cautiously  He did not dismiss the possibility, but carefully went over the many theoretical and practical difficulties involved  Chadwick decided to investigate the properties of uranium oxide further with Rotblat  In March 1940, Otto Frisch and Rudolf Peierls at the University of Birmingham re-examined the theoretical issues involved in a paper that became known as the Frisch–Peierls memorandum  Instead of looking at unenriched uranium oxide, they considered what would happen to a sphere of pure uranium-235, and found that not only could a chain reaction occur, but that it might require as little as 1 kilogram (2 2 lb) of uranium-235, and unleash the energy of tons of dynamite 

A special subcommittee of the Committee for the Scientific Survey of Air Warfare (CSSAW), known as the MAUD Committee, was created to investigate the matter further  It was chaired by Sir George Thomson and its original membership included Chadwick, along with Mark Oliphant, John Cockcroft and Philip Moon  While other teams investigated uranium enrichment techniques, Chadwick's team at Liverpool concentrated on determining the nuclear cross section of uranium-235  By April 1941, it had been experimentally confirmed that the critical mass of uranium-235 might be 8 kilograms (18 lb) or less  His research into such matters was complicated by all-but-incessant Luftwaffe bombings of the environs of his Liverpool lab; the windows were blown out so often that they were replaced by cardboard In July 1941, Chadwick was chosen to write the final draft of the MAUD Report, which, when presented by Vannevar Bush to President Franklin D  Roosevelt in October 1941, inspired the U S  government to pour millions of dollars into the pursuit of an atom bomb  When George B  Pegram and Harold Urey visited Britain to see how the project, now known as Tube Alloys, was going, Chadwick was able to tell them: "I wish I could tell you that the bomb is not going to work, but I am 90 per cent sure that it will "In a recent book about the Bomb project, Graham Farmelo wrote that "Chadwick did more than any other scientist to give Churchill the Bomb      Chadwick was tested almost to the breaking point " So worried that he could not sleep, Chadwick resorted to sleeping pills, which he continued to take for most of his remaining years  Chadwick later said that he realised that "a nuclear bomb was not only possible—it was inevitable  Sooner or later these ideas could not be peculiar to us  Everybody would think about them before long, and some country would put them into action"  Sir Hermann Bondi suggested that it was fortunate that Chadwick, not Rutherford, was the doyen of UK physics at the time, as the latter's prestige might otherwise have overpowered Chadwick's interest in "looking forward" to the Bomb's prospects 

Manhattan Project
Owing to the danger from aerial bombardment, the Chadwicks sent their twins to Canada as part of a government evacuation scheme  Chadwick was reluctant to move Tube Alloys there, believing that the United Kingdom was a better location for the isotope separation plant  The enormous scope of the effort became more apparent in 1942: even a pilot separation plant would cost over £1 million and strain Britain's resources, to say nothing of a full-scale plant, which was estimated to cost somewhere in the vicinity of £25 million  It would have to be built in America  At the same time that the British became convinced that a joint project was necessary, the progress of the American Manhattan Project was such that British cooperation seemed less essential, although the Americans were still eager to utilise Chadwick's talents The matter of cooperation had to be taken up at the highest level  In September 1943, the Prime Minister, Winston Churchill, and President Roosevelt negotiated the Quebec Agreement, which reinstated cooperation between Britain, the United States and Canada  Chadwick, Oliphant, Peierls and Simon were summoned to the United States by the director of Tube Alloys, Sir Wallace Akers, to work with the Manhattan Project  The Quebec Agreement established a new Combined Policy Committee to direct the joint project  The Americans disliked Akers, so Chadwick was appointed technical advisor to the Combined Policy Committee, and the head of the British Mission Leaving Rotblat in charge in Liverpool, Chadwick began a tour of the Manhattan Project facilities in November 1943, except for the Hanford Site where plutonium was produced, which he was not allowed to see  He became the only man apart from Groves and his second in command to have access to all the American research and production facilities for the uranium bomb  Observing the work on the K-25 gaseous diffusion facility at Oak Ridge, Tennessee, Chadwick realised how wrong he had been about building the plant in wartime Britain  The enormous structure could never have been concealed from the Luftwaffe  In early 1944, he moved to Los Alamos, New Mexico, with his wife and their twins, who now spoke with Canadian accents  For security reasons, he was given the cover name of James Chaffee 

Chadwick accepted that the Americans did not need British help, but that it could still be useful in bringing the project to an early and successful conclusion  Working closely with the director of the Manhattan Project, Major General Leslie R  Groves, Jr , he attempted to do everything he could to support the effort  He also endeavoured to place British scientists in as many parts of the project as possible in order to facilitate a post-war British nuclear weapons project to which Chadwick was committed  Requests from Groves via Chadwick for particular scientists tended to be met with an immediate rejection by the company, ministry or university currently employing them, only to be overcome by the overriding priority accorded to Tube Alloys  As a result, the British team was critical to the Project's success Although he had more knowledge of the project than anyone else from Britain, Chadwick had no access to the Hanford site  Lord Portal was offered a tour of Hanford in 1946  "This was the only plant to which Chadwick had been denied access in wartime, and now he asked Groves if he could accompany Portal  Groves replied that he could, but if he did then 'Portal will not see very much' " For his efforts, Chadwick received a knighthood in the New Year Honours on 1 January 1945  He considered this to be a recognition of the work of the whole Tube Alloys project By early 1945, Chadwick was spending most of his time in Washington, D C , and his family relocated from Los Alamos to a house on Washington's Dupont Circle in April 1945  He was present at the meeting of the Combined Policy Committee on 4 July when Field Marshal Sir Henry Maitland Wilson gave Britain's agreement to use the atom bomb against Japan, and at the Trinity nuclear test on 16 July, when the first atom bomb was detonated  Inside its pit was a polonium-beryllium modulated neutron initiator, a development of the technique that Chadwick had used to discover the neutron over a decade before  William L  Laurence, The New York Times reporter attached to the Manhattan Project, wrote that "never before in history had any man lived to see his own discovery materialize itself with such telling effect on the destiny of man "

Later life
Shortly after the war ended, Chadwick was appointed to the Advisory Committee on Atomic Energy (ACAE)  He was also appointed as the British scientific advisor to the United Nations Atomic Energy Commission  He clashed with fellow ACAE member Patrick Blackett, who disagreed with Chadwick's conviction that Britain needed to acquire its own nuclear weapons; but it was Chadwick's position that was ultimately adopted  He returned to Britain in 1946, to find a country still beset by wartime rationing and shortages At this time, Sir James Mountford, the Vice Chancellor of the University of Liverpool, wrote in his diary "he had never seen a man 'so physically, mentally and spiritually tired" as Chadwick, for he "had plumbed such depths of moral decision as more fortunate men are never called upon even to peer into     [and suffered]     almost insupportable agonies of responsibility arising from his scientific work' "In 1948, Chadwick accepted an offer to become the Master of Gonville and Caius College  The job was prestigious but ill-defined; the Master was the titular head of the College, but authority actually resided in a council of 13 fellows, of whom one was the Master  As Master, Chadwick strove to improve the academic reputation of the college  He increased the number of research fellowships from 31 to 49, and sought to bring talent into the college  This involved controversial decisions, such as hiring in 1951 the Chinese biochemist Tien-chin Tsao and the Hungarian-born economist Peter Bauer  In what became known as the Peasants' Revolt, fellows led by Patrick Hadley voted an old friend of Chadwick's off the council and replaced him with Bauer  More friends of Chadwick's were removed over the following years, and he retired in November 1958  It was during his mastership that Francis Crick, a PhD student at Gonville and Caius College, and James Watson discovered the structure of DNA Over the years, Chadwick received many honours, including the Medal for Merit from the United States, and the Pour le Mérite from Germany  He was elected a Fellow of the Royal Society in 1927  He became a foreign member of the Royal Netherlands Academy of Arts and Sciences in 1946 and an International member of the American Philosophical Society in 1948  He was made a Companion of Honour in the New Year Honours on 1 January 1970 for "services to science", and went to Buckingham Palace for the investiture ceremony  He became more frail, and seldom left his flat, although he travelled to Liverpool for celebrations of his eightieth birthday   A lifelong atheist, he saw no reason to adopt religious faith in later life  He died in his sleep on 24 July 1974 His papers are held at the Churchill Archives Centre in Cambridge, and are accessible to the public  The Chadwick Laboratory at the University of Liverpool is named after him, as is its Sir James Chadwick Chair of Experimental Physics, which was named after him in 1991 as part of celebrations of the centenary of his birth  A crater on the moon is also named after him  The James Chadwick Building, which houses part of the School of Chemical Engineering and Analytical Sciences, University of Manchester is named in his honour  He was described by the United Kingdom Atomic Energy Authority official historian Lorna Arnold as "a physicist, a scientist-diplomat, and a good, wise, and humane man "

Notes
Passage 3:
Synthetic element
A synthetic element is one of 24 known chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made"  The synthetic elements are those with atomic numbers 95–118, as shown in purple on the accompanying periodic table: these 24 elements were first created between 1944 and 2010  The mechanism for the creation of a synthetic element is to force additional protons into the nucleus of an element with an atomic number lower than 95  All known (see: Island of stability) synthetic elements are unstable, but they decay at widely varying rates: the half-lives of their longest-lived isotopes range from microseconds to millions of years  
Five more elements that were first created artificially are strictly speaking not synthetic because they were later found in nature in trace quantities: 43Tc, 61Pm, 85At, 93Np, and 94Pu, though are sometimes classified as synthetic alongside exclusively artificial elements  The first, technetium, was created in 1937  Plutonium (Pu, atomic number 94), first synthesized in 1940, is another such element  It is the element with the largest number of protons (atomic number) to occur in nature, but it does so in such tiny quantities that it is far more practical to synthesize it  Plutonium is known mainly for its use in atomic bombs and nuclear reactors No elements with atomic numbers greater than 99 have any uses outside of scientific research, since they have extremely short half-lives, and thus have never been produced in large quantities 

Properties
All elements with atomic number greater than 94 decay quickly enough into lighter elements such that any atoms of these that may have existed when the Earth formed (about 4 6 billion years ago) have long since decayed  Synthetic elements now present on Earth are the product of atomic bombs or experiments that involve nuclear reactors or particle accelerators, via nuclear fusion or neutron absorption Atomic mass for natural elements is based on weighted average abundance of natural isotopes in Earth's crust and atmosphere  For synthetic elements, there is no "natural isotope abundance"  Therefore, for synthetic elements the total nucleon count (protons plus neutrons) of the most stable isotope, i e , the isotope with the longest half-life—is listed in brackets as the atomic mass 

History
Technetium
The first element to be synthesized, rather than discovered in nature, was technetium in 1937  This discovery filled a gap in the periodic table, and the fact that technetium has no stable isotopes explains its natural absence on Earth (and the gap)  With the longest-lived isotope of technetium, 97Tc, having a 4 21-million-year half-life, no technetium remains from the formation of the Earth  Only minute traces of technetium occur naturally in Earth's crust—as a product of spontaneous fission of 238U, or from neutron capture in molybdenum—but technetium is present naturally in red giant stars 

Curium
The first entirely synthetic element to be made was curium, synthesized in 1944 by Glenn T  Seaborg, Ralph A  James, and Albert Ghiorso by bombarding plutonium with alpha particles 

Eight others
Synthesis of americium, berkelium, and californium followed soon  Einsteinium and fermium were discovered by a team of scientists led by Albert Ghiorso in 1952 while studying the composition of radioactive debris from the detonation of the first hydrogen bomb  The isotopes synthesized were einsteinium-253, with a half-life of 20 5 days, and fermium-255, with a half-life of about 20 hours  The creation of mendelevium, nobelium, and lawrencium followed 

Rutherfordium and dubnium
During the height of the Cold War, teams from the Soviet Union and the United States independently created rutherfordium and dubnium  The naming and credit for synthesis of these elements remained unresolved for many years, but eventually shared credit was recognized by IUPAC/IUPAP in 1992  In 1997, IUPAC decided to give dubnium its current name honoring the city of Dubna where the Russian team worked since American-chosen names had already been used for many existing synthetic elements, while the name rutherfordium (chosen by the American team) was accepted for element 104 

The last thirteen
Meanwhile, the American team had created seaborgium, and the next six elements had been created by a German team: bohrium, hassium, meitnerium, darmstadtium, roentgenium, and copernicium  Element 113, nihonium, was created by a Japanese team; the last five known elements, flerovium, moscovium, livermorium, tennessine, and oganesson, were created by Russian–American collaborations and complete the seventh row of the periodic table 

List of synthetic elements
The following elements do not occur naturally on Earth  All are transuranium elements and have atomic numbers of 95 and higher 

Other elements usually produced through synthesis
All elements with atomic numbers 1 through 94 occur naturally at least in trace quantities, but the following elements are often produced through synthesis: technetium, promethium, astatine, neptunium, and plutonium, which were discovered through synthesis before being found in nature 
Passage 4:
Atomic number
The atomic number or nuclear charge number (symbol Z) of a chemical element is the charge number of an atomic nucleus  For ordinary nuclei composed of protons and neutrons, this is equal to the proton number (np) or the number of protons found in the nucleus of every atom of that element  The atomic number can be used to uniquely identify ordinary chemical elements  In an ordinary uncharged atom, the atomic number is also equal to the number of electrons 
For an ordinary atom which contains protons, neutrons and electrons, the sum of the atomic number Z and the neutron number N gives the atom's atomic mass number A  Since protons and neutrons have approximately the same mass (and the mass of the electrons is negligible for many purposes) and the mass defect of the nucleon binding is always small compared to the nucleon mass, the atomic mass of any atom, when expressed in daltons (making a quantity called the "relative isotopic mass"), is within 1% of the whole number A 
Atoms with the same atomic number but different neutron numbers, and hence different mass numbers, are known as isotopes  A little more than three-quarters of naturally occurring elements exist as a mixture of isotopes (see monoisotopic elements), and the average isotopic mass of an isotopic mixture for an element (called the relative atomic mass) in a defined environment on Earth, determines the element's standard atomic weight  Historically, it was these atomic weights of elements (in comparison to hydrogen) that were the quantities measurable by chemists in the 19th century 
The conventional symbol Z comes from the German word Zahl 'number', which, before the modern synthesis of ideas from chemistry and physics, merely denoted an element's numerical place in the periodic table, whose order was then approximately, but not completely, consistent with the order of the elements by atomic weights  Only after 1915, with the suggestion and evidence that this Z number was also the nuclear charge and a physical characteristic of atoms, did the word Atomzahl (and its English equivalent atomic number) come into common use in this context 
The rules above do not always apply to exotic atoms which contain short-lived elementary particles other than protons, neutrons and electrons 

History
The periodic table and a natural number for each element
Loosely speaking, the existence or construction of a periodic table of elements creates an ordering of the elements, and so they can be numbered in order 
Dmitri Mendeleev claimed that he arranged his first periodic tables (first published on March 6, 1869) in order of atomic weight ("Atomgewicht")  However, in consideration of the elements' observed chemical properties, he changed the order slightly and placed tellurium (atomic weight 127 6) ahead of iodine (atomic weight 126 9)  This placement is consistent with the modern practice of ordering the elements by proton number, Z, but that number was not known or suspected at the time 

A simple numbering based on periodic table position was never entirely satisfactory, however  Besides the case of iodine and tellurium, later several other pairs of elements (such as argon and potassium, cobalt and nickel) were known to have nearly identical or reversed atomic weights, thus requiring their placement in the periodic table to be determined by their chemical properties  However the gradual identification of more and more chemically similar lanthanide elements, whose atomic number was not obvious, led to inconsistency and uncertainty in the periodic numbering of elements at least from lutetium (element 71) onward (hafnium was not known at this time) 

The Rutherford-Bohr model and van den Broek
In 1911, Ernest Rutherford gave a model of the atom in which a central nucleus held most of the atom's mass and a positive charge which, in units of the electron's charge, was to be approximately equal to half of the atom's atomic weight, expressed in numbers of hydrogen atoms  This central charge would thus be approximately half the atomic weight (though it was almost 25% different from the atomic number of gold (Z = 79, A = 197), the single element from which Rutherford made his guess)  Nevertheless, in spite of Rutherford's estimation that gold had a central charge of about 100 (but was element Z = 79 on the periodic table), a month after Rutherford's paper appeared, Antonius van den Broek first formally suggested that the central charge and number of electrons in an atom was exactly equal to its place in the periodic table (also known as element number, atomic number, and symbolized Z)  This proved eventually to be the case 

Moseley's 1913 experiment
The experimental position improved dramatically after research by Henry Moseley in 1913  Moseley, after discussions with Bohr who was at the same lab (and who had used Van den Broek's hypothesis in his Bohr model of the atom), decided to test Van den Broek's and Bohr's hypothesis directly, by seeing if spectral lines emitted from excited atoms fitted the Bohr theory's postulation that the frequency of the spectral lines be proportional to the square of Z 
To do this, Moseley measured the wavelengths of the innermost photon transitions (K and L lines) produced by the elements from aluminium (Z = 13) to gold (Z = 79) used as a series of movable anodic targets inside an x-ray tube  The square root of the frequency of these photons (x-rays) increased from one target to the next in an arithmetic progression  This led to the conclusion (Moseley's law) that the atomic number does closely correspond (with an offset of one unit for K-lines, in Moseley's work) to the calculated electric charge of the nucleus, i e  the element number Z  Among other things, Moseley demonstrated that the lanthanide series (from lanthanum to lutetium inclusive) must have 15 members—no fewer and no more—which was far from obvious from known chemistry at that time 

Missing elements
After Moseley's death in 1915, the atomic numbers of all known elements from hydrogen to uranium (Z = 92) were examined by his method  There were seven elements (with Z < 92) which were not found and therefore identified as still undiscovered, corresponding to atomic numbers 43, 61, 72, 75, 85, 87 and 91  From 1918 to 1947, all seven of these missing elements were discovered  By this time, the first four transuranium elements had also been discovered, so that the periodic table was complete with no gaps as far as curium (Z = 96) 

The proton and the idea of nuclear electrons
In 1915, the reason for nuclear charge being quantized in units of Z, which were now recognized to be the same as the element number, was not understood  An old idea called Prout's hypothesis had postulated that the elements were all made of residues (or "protyles") of the lightest element hydrogen, which in the Bohr-Rutherford model had a single electron and a nuclear charge of one  However, as early as 1907, Rutherford and Thomas Royds had shown that alpha particles, which had a charge of +2, were the nuclei of helium atoms, which had a mass four times that of hydrogen, not two times  If Prout's hypothesis were true, something had to be neutralizing some of the charge of the hydrogen nuclei present in the nuclei of heavier atoms 
In 1917, Rutherford succeeded in generating hydrogen nuclei from a nuclear reaction between alpha particles and nitrogen gas, and believed he had proven Prout's law  He called the new heavy nuclear particles protons in 1920 (alternate names being proutons and protyles)  It had been immediately apparent from the work of Moseley that the nuclei of heavy atoms have more than twice as much mass as would be expected from their being made of hydrogen nuclei, and thus there was required a hypothesis for the neutralization of the extra protons presumed present in all heavy nuclei  A helium nucleus was presumed to be composed of four protons plus two "nuclear electrons" (electrons bound inside the nucleus) to cancel two of the charges  At the other end of the periodic table, a nucleus of gold with a mass 197 times that of hydrogen was thought to contain 118 nuclear electrons in the nucleus to give it a residual charge of +79, consistent with its atomic number 

The discovery of the neutron makes Z the proton number
All consideration of nuclear electrons ended with James Chadwick's discovery of the neutron in 1932  An atom of gold now was seen as containing 118 neutrons rather than 118 nuclear electrons, and its positive nuclear charge now was realized to come entirely from a content of 79 protons  Since Moseley had previously shown that the atomic number Z of an element equals this positive charge, it was now clear that Z is identical to the number of protons of its nuclei 

Chemical properties
Each element has a specific set of chemical properties as a consequence of the number of electrons present in the neutral atom, which is Z (the atomic number)  The configuration of these electrons follows from the principles of quantum mechanics  The number of electrons in each element's electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior  Hence, it is the atomic number alone that determines the chemical properties of an element; and it is for this reason that an element can be defined as consisting of any mixture of atoms with a given atomic number 

New elements
The quest for new elements is usually described using atomic numbers  As of 2023, all elements with atomic numbers 1 to 118 have been observed  Synthesis of new elements is accomplished by bombarding target atoms of heavy elements with ions, such that the sum of the atomic numbers of the target and ion elements equals the atomic number of the element being created  In general, the half-life of a nuclide becomes shorter as atomic number increases, though undiscovered nuclides with certain "magic" numbers of protons and neutrons may have relatively longer half-lives and comprise an island of stability  
A hypothetical element composed only of neutrons has also been proposed and would have atomic number 0 

See also



ground_truth: 22

prompt_front: Answer the question based on the given passages. Only give me the answer and do not output any other words.

Question: What is the source of the river that is the mouth of the Caledon River?

The following are given passages.
Context 2: Passage 1:
Rufiji River
The Rufiji River lies entirely within Tanzania  It is also the largest and longest river in the country  The river is formed by the confluence of the Kilombero and Luwegu rivers  It is approximately 600 kilometres (370 mi) long, with its source in southwestern Tanzania and its mouth on the Indian Ocean opposite Mafia Island across the Mafia Channel, in Pwani Region  Its principal tributary is the Great Ruaha River  It is navigable for approximately 100 kilometres (62 mi) 
The Rufiji river is approximately 200 kilometres (120 mi) south of Dar es Salaam  The river's delta contains the largest mangrove forest in eastern Africa 

History
A branch of ancient sea routes led down the East African coast called "Azania" by the Greeks and Romans in the 1st century CE as described in the Periplus of the Erythraean Sea (and, very probably, Chinese: 澤散 in the 3rd century by the Chinese), at least as far as the port known to the Romans as Rhapta, which was probably located in the delta of the Rufiji River in modern Tanzania During the First World War, from October 1914 to July 1915, the river delta was the scene of a protracted naval operation  These were the attempts, and later achievement, by the Royal Navy to neutralize and destroy the German cruiser Konigsberg 

Basin
The catchment basin for the Rufiji River complex is 177,429 square kilometres (68,506 sq mi) 

Hydroelectric Project
Tanzania president John Magufuli has approved the construction of a controversial new dam and power station on the river at Stiegler's Gorge  The power station is expected to provide 2,100 megawatts of electricity, more than triple Tanzania's existing installed hydropower capacity which is only 562 megawatts  Construction of the dam started on July 26, 2019, and it is expected be ready by 2022 
Passage 2:
Wolli Creek
Wolli Creek () is an urban watercourse of the Cooks River catchment located in the southern suburbs of Sydney, in New South Wales, Australia 

Course and features
Wolli Creek rises south of Narwee, within Beverly Hills Park, Beverly Hills, and flows generally east northeast through Wolli Creek Valley and Wolli Creek Regional Park, joined by its major tributary, Bardwell Creek, before reaching its confluence with the Cooks River near Arncliffe and Tempe  The creek is a lined channel between Kingsgrove Road, Kingsgrove and Bexley Road, Bexley North where it then enters the Wolli Creek Valley  The sub-catchment area of the creek is 22 square kilometres (8 5 sq mi) 

Nature conservation value
Adjacent to Wolli Creek, within the Wolli Creek Valley, is Wolli Creek Regional Park, a planned 50 hectares (120 acres) nature reserve of native bushland and public reserves that was announced by the NSW Government in 1998 as a result of sustained community campaigning for the area to be preserved and for the M5 East Freeway to go underground  Whilst some of the park has been formed and management handed over from local government authorities to the NSW National Parks & Wildlife Service, including the 8 9 hectares (22 acres) Girrahween Park and some privately held land that was compulsorily acquired, some areas of the originally planned park remain in the hands of government agencies including Sydney Water and Roads & Maritime Services When complete, the planned nature reserve offers easy public transport access, family picnic areas, extensive views and bushland, rugged sandstone escarpments with walking tracks, a mixture of parkland, heathland, and woodland forest, and great birdwatching in close proximity to heavily developed residential and industrial landscape 

Wildlife
Bird observation
The diversity of habitat and strategic location of the Wolli Creek Valley are reflected in the wide range of bird species to be found adjacent to the creek  Approximately 175 species of birds have been recorded in the area between 1940 and 1999 

Fish
Several species of freshwater and saltwater fish can be found in the Wolli Creek in areas above and below the fish ladder  The fish ladder, or "rock-ramp fishway" was constructed to enable fish to bypass the weir at Henderson St, Turrella, allowing migration to other areas of the creek 

Coastal saltmarsh
The lower reaches – the tidal part – of Wolli Creek are home to a plant community known as saltmarsh, or coastal saltmarsh  The plant community includes various salinity-tolerant species such as Knobby Club-rush (Ficinia nodosa), Samphire (Sarcocornia quinqueflora), Sea Rush (Juncus kraussii), Seablite (Suaeda australis), Streaked Arrowgrass (Triglochin striata) and others  Coastal saltmarsh has been recognised as a carbon sink as well as a filter of nutrients maintaining water quality and is listed as an Endangered Ecological Community under the Threatened Species Conservation Act 1995 

Gallery
See also
Wolli Creek Regional Park
Passage 3:
Darling Mills Creek
The Darling Mills Creek, an urban watercourse that is part of the Parramatta River catchment, is located in Greater Western Sydney, New South Wales, Australia 

Course and features
The Darling Mills Creek rises in the north-western suburbs of Sydney, west of Thompsons Corner, near the intersection of Castle Hill Road and Pennant Hills Road, within the suburb of West Pennant Hills  The headwaters lie on the watershed between the Hornsby Plateau and the Cumberland Plain  The creek flows generally west, then south, joined by its tributaries including the Bidjigal, Sawmill, Excelsior, Blue Gum, Bellbird, Bellamy Farm creeks and the dammed Hunts Creek downstream of Lake Parramatta, before reaching its confluence with the Toongabbie Creek to form the Parramatta River, in the suburb of North Parramatta, in land adjoining the northern boundary of the Cumberland Hospital  The course of the creek is approximately 10 kilometres (6 2 mi); and the creek passes through the Cumberland State Forest, the Darling Mills State Forest, Bidjigal Reserve, Excelsior Park, and many smaller reserves and parks The Darling Mills Creek is transversed by the Cumberland Highway, the M2 Hills Motorway, and marks the boundary between Windsor Road and Church Street in North Parramatta 

History
The land adjacent to the Parramatta River and its tributaries, including the Darling Mills Creek, was occupied for many thousands of years by the Burramattagal clan of the Darug people, Toongagal, Wallumattagal, Wangal, and Wategora Aboriginal peoples  They used the river as an important source of food and a place for trade The Darling Mills Creek takes its name from a watermill constructed a short distance from the confluence with Toongabbie Creek 
An earlier watermill was built by Samuel Marsden near the confluence  It milled flour from 1804 to 1818 
In 1825, the Darling Flour Mills were built for John Raine, upstream on the Windsor Road 
The Darling Mills site was taken over by Sydney Woollen Mills, which operated from 1870 to 1975  Sydney Woollen Mills originally used steam rather than water power  Part of the facade of the building remains on the site, which was occupied by Bunnings Warehouse's North Parramatta store in the early 21st century  There is a weir on the creek nearby that was constructed in the nineteenth century 

See also
Great North Walk
Rivers of New South Wales
Passage 4:
Still Fork
Still Fork is a tributary of the Sandy Creek, 16 1 miles (26 km) long, in eastern Ohio in the United States   Via the Sandy Creek, Tuscarawas, Muskingum and Ohio Rivers, it is part of the watershed of the Mississippi River, draining an area of 71 4 square miles (185 km2) in Carroll County, Ohio   The source is at 1,180 feet (360 m) and the mouth is at 1,027 feet (313 m) , with an average gradient of only 0 2%   From its source in eastern Carroll County the creek flows northwest through Fox, Washington, Augusta, and Brown Townships before reaching its mouth in Minerva, Ohio   The Ohi-Rail Corporation (OHIC) and Arbor road are situated in the creeks valley over most of its length 
Near Augusta the creek flows through a rural Amish community, and downstream of Ohio State Route 9 is the unincorporated community of Pattersonville   Mechanicstown and Norristown are the only other named communities in the watershed 

Variant names
According to the Geographic Names Information System, Still Fork has had no other known names 

Still Fork of Sandy Navigation Company
On February 15, 1837, the General Assembly of the state of Ohio enacted AN ACT to incorporate the Still Fork of Sandy Navigation Company   This act authorized seven named Carroll county men to form the company to “…locate, make, construct, and forever maintain, a navigable canal or slack-water navigation, commencing on the land of William Croxton, where the New Lisbon-Carrollton road crosses said Still Fork of Sandy, and thence with the  general course of said stream, to intersect the Sandy and Beaver Canal, at the town of Pekin, in said county of Carroll…with the full power to emyloy [sic], as reservoirs or feeders, all streams or ponds over or near which such canal or slack-water navigation may pass ”  The company was capitalized at $65,000 in $25 shares to be sold to individuals only    William Croxton’s land was in section 11 of Washington Township, a short distance up Friday Creek from the main branch of Still Fork, and present day county road 71 was the road between Carrollton and Lisbon 

Named tributaries
See also
List of rivers of Ohio
Passage 5:
Arado River
The Arado river is a river that originates in the surroundings of Curral do Camalhão, Gerês mountain range, north of the Teixeira valley and flows into the Fafião river after the Cascatas de Fecha be Barjas, parish of Cabril, municipality of Montalegre, district of Vila Real, in the north of Portugal   It lies within the Peneda-Gerês National Park 
Passage 6:
Loimijoki
The river Loimijoki is a river in Finland and the longest tributary of the river Kokemäenjoki  The river originates at the lake Pyhäjärvi in Tammela and joins the river Kokemäenjoki in Huittinen  There is a 54-metre (177 ft) difference in elevation between the source and the mouth of the river, which is 114 kilometres (71 mi) long  The river drains a catchment area of 3,140 square kilometres (1,210 sq mi)  The river has several dams at Forssa, Jokioinen and Loimaa The Loimijoki river runs through the most fertile lands of Finland making its water  relatively muddy  The river was badly polluted by sewage of industry and population centers along the river, but since the 1980s the river has been starting to recover and currently the river sees also recreational use like fishing and water sports 
Passage 7:
Bolshaya Lyampa
The Bolshaya Lyampa (Russian: Большая Лямпа) is a river in Perm Krai, Russia, a right tributary of the Uls which in turn is a tributary of the Vishera  The river is 34 kilometres (21 mi) long  Its source is near the border with Sverdlovsk Oblast  It flows into the Uls 55 kilometres (34 mi) from the larger river's mouth  The Bolshaya Lyampa's main tributary is the Malaya Lyampa 
Passage 8:
Upper Orange Water Management Area
Upper Orange WMA, or Upper Orange Water Management Area (coded: 13), Includes the following major rivers: the Modder River, Riet River, Caledon River and Orange River, and covers the following Dams:

Armenia Dam Leeu River
Egmont Dam Witspruit
Gariep Dam Orange River
Groothoek Dam Kgabanyane River
Kalkfontein Dam Riet River
Katse Dam Malibamatso River
Knellpoort Dam Rietspruit
Krugersdrift Dam Modder River
Mohale Dam Senqunyane River
Rustfontein Dam Modder River
Tierpoort Dam Tierpoort River
Vanderkloof Dam Orange River
Welbedacht Dam Caledon River

Boundaries
Tertiary drainage regions C51, C52, D11 to D18, D21 to D24, D31, D32, D34 and D35 

See also
Water Management Areas
List of reservoirs and dams in South Africa
List of rivers of South Africa
Passage 9:
Orange River
The Orange River (from Afrikaans/Dutch: Oranjerivier) is a river in Southern Africa  It is the longest river in South Africa  With a total length of 2,432 km (1,511 mi), the Orange River Basin extends from Lesotho into South Africa and Namibia to the north  It rises in the Drakensberg mountains in Lesotho, flowing westwards through South Africa to the Atlantic Ocean  The river forms part of the international borders between South Africa and Lesotho and between South Africa and Namibia, as well as several provincial borders within South Africa  Except for Upington, it does not pass through any major cities  The Orange River plays an important role in the South African economy by providing water for irrigation and hydroelectric power  The river was named the Orange River in honour of the Dutch ruling family, the House of Orange, by the Dutch explorer Robert Jacob Gordon  Other names include simply the word for river, in Khoekhoegowab orthography written as !Garib, which is rendered in Afrikaans as Gariep River with the intrusion of a velar fricative in place of the alveolar click, Groote River (derived from Kai !Garib) or Senqu River (used in Lesotho), derived from ǂNū "Black"  It is known in isiZulu as isAngqu 

Course
The Orange rises in the Drakensberg mountains along the border between South Africa and Lesotho, about 193 km (120 mi) west of the Indian Ocean and at an altitude of over 3,000 m (9,800 ft)  The extremity of the Orange River inside Lesotho is known as the Senqu  Parts of the Senqu River freeze in winter because of the high altitude  This creates droughts downstream, which mainly affect goat and cattle production 

The Orange River then runs westward through South Africa, forming the south-western boundary of the Free State province  In this section, the river flows first into the Gariep Dam and later into the Vanderkloof Dam  From the border of Lesotho to below the Vanderkloof Dam, the river bed is deeply incised  Further downstream, the land is flatter, and the river is used extensively for irrigation 
At the western point of the Free State, southwest of Kimberley, the Orange meets with its main tributary, the Vaal River, which forms much of the northern border of the province  From here, the river flows further westward through the arid wilderness of the southern Kalahari region and Namaqualand in the Northern Cape province to meet with Namibia at 20°E longitude  From here, it flows westward for 550 km (340 mi), forming the international border between the province and Namibia's ǁKaras Region  On the border, the river passes the town of Vioolsdrif, the main border post between South Africa and Namibia 

In the last 800 km (500 mi) of its course, the Orange receives many intermittent streams, and several large wadis lead into it  In this section, the Namib Desert terminates on the north bank of the river, so under normal circumstances, the volume of water added by these tributaries is negligible  Here, the bed of the river is once again deeply incised  The Augrabies Falls are located on this section of the Orange, where the river descends 122 m (400 ft) in a course of 26 km (16 mi) 
The Orange empties into the Atlantic Ocean between the small towns of Oranjemund (meaning "Orange mouth") in Namibia and Alexander Bay in South Africa, about equidistant between Walvis Bay and Cape Town  Some 33 km (21 mi) from its mouth, it is obstructed by rapids and sand bars and is generally not navigable for long stretches 
The river has a total length of 2,432 km (1,511 mi) 

Catchment and rainfall
In the dry season, the volume of the water in the river is considerably reduced because of the rapid run-off and evaporation  At the source of the Orange, the rainfall is about 2,000 mm (79 in) per annum, but precipitation decreases as the river flows westward; at its mouth, the rainfall is less than 50 mm (2 0 in) per year  The factors that support evaporation, though, tend to increase in a westerly direction  In the wet season (summer), the Orange river becomes a brown colored torrent  The huge mass of sediment carried constitutes a long-term threat to engineering projects on the river The total catchment of the Orange River (including the Vaal) extends over 973,000 km2 (376,000 sq mi), i e  equivalent to about 77% of the land area of South Africa (1,221,037 km2 (471,445 sq mi))  Around 366,000 km2 (141,000 sq mi) (38%), however, are situated outside the country in Lesotho, Botswana, and Namibia 

Tributaries
Vaal River - 1,458 km (906 mi)
Caledon River - 642 km (399 mi)
Khubelu River - 144 km (89 mi)

Dams
Armenia Dam
Egmont Dam
Gariep Dam
Newberry Dam
Vanderkloof Dam
Welbedacht Dam

History
Etymology
Some of the earliest precolonial inhabitants called the river ǂNūǃarib, referring to its black colour, or sometimes just Kai !Arib ("Great River"), from which is derived the Afrikaans version Gariep, and translation "Groote Rivier"  The early Dutch name for the river was just that translation, Groote Rivier, meaning "Great River"  The river was named the Orange River by Colonel Robert Gordon, commander of the United East India Company (VOC) garrison at Cape Town, on a trip to the interior in 1779  Gordon named the river in honor of William V of Orange  A popular but incorrect belief is that the river was named after the supposedly orange color of its water, as opposed to the color of its tributary, the Vaal River, which name is derived from the name ǀHaiǃarib "pale river" (vaal being Afrikaans for pale or grey)  Since the end of apartheid, the name "Gariep" has had greater favour in official correspondence in South Africa, although the name "Orange" has greater international recognition  In Lesotho, where the river rises, it is known as the Senqu River, derived from the original Khoemana name 

The Eastern Cape Geographical Names Committee has advertised its intention to consider a name change from the colonial name, for that portion of the river that forms the border between the Eastern Cape and the Free State, with suggestions being IGqili or Senqu  The advertisement placed in the Aliwal Weekblad newspaper states that the "present name is perceived to have a strong association with the history of colonial subjugation and has therefore no place under the current democratic dispensation "

The Grootslang
In South African folklore, the Orange River is often associated with the Grootslang, a mythical being resembling a giant serpent, which is often connected to the river's alluvial diamonds  The Grootslang is described as living in a gem-filled cave connected to the Orange River by a natural pipe through which the diamonds gradually enter the river  Other sites said to be lairs of the creature include the pool beneath the King George Cataract at Aughrabies Falls, which is also said to be a source of diamonds, and a large rock in the middle of the river itself  In this version of the legend, the Grootslang is also said to prey on cattle from the river's banks 

Economy
As the collection point for the majority of South Africa's water, the Orange River plays a major role in supporting agriculture, industry, and mining  To assist in this, two large water schemes have been created, the Orange River Project and the Lesotho Highlands Water Project  Historically, the river played an important role in the South African diamond rush, with the first diamonds in the country being discovered in alluvial deposits on the Orange  Today, several commercial diamond mines operate along the final stretch of the Orange River and around its mouth 
Because of the lack of dangerous animals and high water levels during summer, the river is used for recreational canoeing and rafting  Orange River rafting has become very popular with many companies using their camps along the river from which to operate  The most popular trips are four-day and six-day river trips that take place either along the gorge below the Augrabies Falls or along the Richtersveld area 

Orange River Project
The Orange River Project (ORP) was one of the largest and most imaginative projects of its kind in South Africa  It was constructed by Hendrik Verwoerd's government at the height of the apartheid era  The ORP was built to exploit the waters of the Orange River—which, without the Vaal River, represents some 14 1% of the total runoff in South Africa—and in the process, to satisfy an increasing demand for water  The main objectives of the project were:

to stabilise river flow,
the generation and transmission of hydroelectric power,
to provide a reliable water supply for users in the Orange River basin, and
to give a new lease on life to water-deficient areas in the Eastern Cape, such as the Great Fish and Sundays River valleys The Gariep Dam near Colesberg is the main storage structure within the Orange River  From here, the water is supplied in two directions, westward along the Orange River (via hydroelectric power generators) to the Vanderkloof Dam and southward through the Orange-Fish Tunnel to the Eastern Cape 

Hydroelectricity
Eskom operates hydroelectric power stations at both the Gariep Dam and the Vanderkloof Dam  The hydroelectric power station at the Vanderkloof Dam was the first power-generation station in South Africa situated entirely underground  The towns Oviston and Oranjekrag were established to facilitate the construction and operation of the new infrastructure 

Irrigation
Irrigation in the vast area downstream of the Vanderkloof Dam, which has turned thousands of hectares of arid veld into highly productive agricultural land, was made possible by the construction of the Gariep and Vanderkloof Dams  Old established irrigation schemes such as those at Buchuberg, Upington, Kakamas, and Vioolsdrif have also benefitted because regulation of the flow is now possible  On the Namibian side of the river, Aussenkehr produces grapes with the help of water from the Orange 
In recent years, the wine-producing areas along the Orange River have grown in importance  Irrigation in the Eastern Cape has also received a tremendous boost, not only from the additional water being made available, but also owing to improvement in water quality  Without this improvement, the citrus farmers along the Lower Sundays River would almost certainly have continued to suffer losses of productivity 

Lesotho Highlands Water Project
The Lesotho Highlands Water Project was conceived to supplement the water supply in the Vaal River System  Water is delivered to South Africa by means of the delivery tunnel which passes under the Lesotho South Africa border at the Caledon River, and then under the Little Caledon River south of Clarens in the Free State, and discharges into the Ash River about 30 kilometres (19 mi) further to the north  The scheme became viable when water demands in Gauteng reached levels that could no longer be supported economically by alternative schemes such as the Tugela River-Vaal River pumped storage scheme, which used the Sterkfontein Dam, located near Harrismith in the Free State 

Alluvial diamonds
In 1867, the first diamond discovered in South Africa, the Eureka Diamond, was found near Hopetown on the Orange River  Two years later, a much larger diamond known as the Star of South Africa was found in the same area, causing a diamond rush  This was soon eclipsed by the diamond rush to mine diamonds directly from kimberlite at Kimberley in 1871, although alluvial diamonds continued to be found in the Orange  Today, several commercial diamond mines operate on the last stretch of the river, as well as the beaches around its mouth  Diamond mines also operate on the middle stretch of the river 

Rafting and canoeing
During the temperate months of March and April, given good rains and the sluices of the dams being open, a canoeist (or rafter) can easily travel 30 kilometres (19 mi) per day  The lower reaches of the river are most popular, because of the spectacular topography  Commercial tours are available, and these expeditions depart from the border town of Vioolsdrif 

Wildlife
The Orange River has no large animals  It lies outside the range of the Nile crocodile, and although hippopotami were once abundant, they were hunted to extermination in the 19th century  The Orange River has a relative paucity of species diversity  A 2011 survey of 13,762 fish found only 16 species of fish present   Three of these, the common carp, the Mozambique tilapia, and the western mosquitofish are not indigenous   Another exotic species, rainbow trout, is found in the river headwaters in Lesotho 
Seven species are endemic to the Vaal-Orange River system:
Rock-catfish (Austroglanis sclateri)
Maluti redfin or Maloti minnow (Pseudobarbus quathlambae)
Namaquab barb (Barbus hospes)
River sardine (Mesobola brevianalis)
Smallmouth yellowfish (Labeobarbus aeneus)
Largemouth yellowfish (Labeobarbus kimberlyensis)
Orange River Mudfish (Labeo capensis)

See also
List of rivers in South Africa
List of international border rivers
List of crossings of the Orange River
Passage 10:
Bardwell Creek
Bardwell Creek, an urban watercourse of the Cooks River catchment, is located in the southern suburbs of Sydney, in New South Wales, Australia 

Course and features
Bardwell Creek rises in Georges River local government area, near Hurstville and flows in a north-easterly direction through the suburbs of Bexley, Bexley North, Bardwell Park, and Turrella in the Bayside local government area, where it makes its confluence with Wolli Creek, where it forms the border between the suburbs of Bardwell Park and Turrella  The upper reaches of the Creek are a piped drainage system, which becomes an open concrete channel at Croydon Road in the Bexley Golf Course  The total catchment area of Bardwell Creek is 6 36 square kilometres (2 46 sq mi) 

See also
Bardwell Valley, New South Wales
Wolli Creek Regional Park
Passage 11:
Reconquista River
The Reconquista River (Spanish, Río Reconquista) is a small river in the province of Buenos Aires, Argentina  Together with the Riachuelo, it is one of the most contaminated watercourses in the country 
The Reconquista is part of the Río de la Plata basin  It originates in Marcos Paz, Buenos Aires Province, and flows across 18 municipalities, emptying into the Luján River  Its drainage basin has an area of 1,670 square kilometres (640 sq mi) and is populated by around 4 million people 
The river carries about 33 percent of the total pollution drained by the  estuary of the Río de la Plata, taking into account both industrial and domestic waste  There are about 12,000 industries in its basin, 700 of which dump their waste into the watercourse without controls 
Studies have found nitrites, nitrates, ester-phenols, PCB, and heavy metals  These pollutants can cause hepatitis, skin reactions, gastrointestinal problems and eye infections 

History
During the 1980s, there was a wave of protests by local residents denouncing the lack of state involvement  In 1984, the national Senate addressed the issue for the first time 
In 1995, the national government obtained a loan from the Inter-American Development Bank for the cleaning and control of the Reconquista  The construction started in 1996, with a $400 million budget assigned to an autonomous entity called UniRec 
In 2001 they were officially finished, and advertised as such, though only the flood prevention works were built  Four projected waste treatment plants and other  sanitation infrastructure were not  There was also no minimization or monitoring of industrial waste dumped into the course 
According to Martín Nunziata, member of a Río de la Plata environmental group, this failure to comply with the plan was the result of political corruption, and also due to the pressure exerted by the polluting industries on the workers: "The companies warn [them] that, if the environmental laws are applied, they will have to close "
Nunziata also alluded to the cellulose plant conflict between Argentina and Uruguay: "If, starting today, it was decided to demand from the industries of the Reconquista River the same things we want Uruguay to demand from the Fray Bentos cellulose plants, out of the 12,000 companies installed, at least 10,000 would have to close down "

Destroyed historic bridge
The 1773 Marquez Bridge over the Reconquista River was declared a National Historic Monument of Argentina, but in 1997, the Autopistas del Oeste demolished it 

See also
List of rivers of Argentina
List of destroyed heritage § Argentina
List of National Historic Monuments of Argentina
Passage 12:
Coxs Creek (Belfield, New South Wales)
Coxs Creek, a watercourse of the Cooks River catchment, is located in the Inner West of Sydney, in New South Wales, Australia 

Course and features
Coxs Creek rises northeast of Punchbowl railway station and flows generally north northeast, before reaching its confluence with the Cooks River, at Strathfield South  Over time the creek has been extensively modified and is now largely a storm drain that flows about 3 kilometres (1 9 mi)  Prior to development of the area the creek drained paperbark swamps that were formerly near the junction of Roberts Road and Juno Parade  Over time the creek has been extensively modified and rerouted  As with most drainage channels in the area it has been lined along much of its length  Coxs Creek drains a total catchment of 8 8 square kilometres (3 4 sq mi) The creek begins as a stormwater drain, then runs in the open through the Coxs Creek Wetland, a 1 84 hectares (4 5 acres) reserve containing significant remnant bushland including some Cooks River Castlereagh Ironbark Forest habitat  Including tree specimens of mugga ironbark (Eucalyptus sideroxylon), narrow-leaved ironbark (E  crebra), broad-leaved ironbark (E  fibrosa), and tallowwood (E  microcorys)  The forest habitat is noted as an endangered ecological community  Acacia pubescens (Downy Wattle) is a vulnerable flora species present as is the locally endangered Tadgell's Bluebell (Wahlenbergia multicaulis)  The endangered Green and Golden Bell Frog (Litoria aurea) has been recorded and frog ponds constructed as part of the creek  The frog has not been seen in the creek since 1995, though they are still present in the nearby constructed wetlands at the Juno Parade Brick Pit 
In 2005 Sydney Ports Corporation proposed works including fauna corridors and "frog ramps" to encourage their return  Along much of its length the creek is a combination of covered channel and an uncovered concrete lined trench  As the creek passes through the reserve it is open and the 2010 management plan calls for restoration of this part of the creek and the adjacent riparian zone 
Passage 13:
Toongabbie Creek
Toongabbie Creek, an urban watercourse that is part of the Parramatta River catchment, is located in Greater Western Sydney, New South Wales, Australia 

Course and features
Toongabbie Creek rises in the north-western suburbs of Sydney, west of the Old Northern Road, within the suburb of Castle Hill; with its headwaters forming the watershed boundary between the Hornsby Plateau and the Cumberland Plain  The creek flows generally south-west, then south by east, then south by west, then east before reaching its confluence with the Darling Mills Creek to form the Parramatta River, in the suburb of North Parramatta, in land adjoining the northern boundary of the Cumberland Hospital  The course of the creek is approximately 9 kilometres (5 6 mi) Although only a small portion of Toongabbie Creek is contained within the Blacktown local government area, much of its sub-catchment, including the Blacktown and Lalor creeks and their associated tributaries are within the City of Blacktown  In 2005, the Toongabbie Creek catchment area was rated as the highest polluting catchment out of the twenty-two catchments in Blacktown  Much of the creek is channeled in a concrete drain; and domestic garbage is often scattered along the creek's banks  Prior to April 2015, the creek was dammed at many places by fallen trees, and the rapids at Mons Road were not visible  The stagnant water in the dams was bubbly  After the rain in April 2015, which caused a flood that damaged infrastructure at Parramatta,  most of the dead trees were cleaned away and the rocks at Mons Road are now exposed 
Toongabbie Creek is transversed by the Cumberland Highway; the Westlink M7 and M2 Hills Motorway at their interchange; and the Old Windsor Road 
The land adjacent to the Parramatta River and its tributaries, including the Toongabbie Creek, was occupied for many thousands of years by the Burramattagal, Toongagal, Wallumattagal, Wangal, and Wategora Aboriginal peoples  They used the river as an important source of food and a place for trade 

See also
Rivers of New South Wales
Passage 14:
Cabramatta Creek
Cabramatta Creek, an urban watercourse of the Georges River catchment, is located in the South Western Sydney, in New South Wales, Australia 

Course and features
Cabramatta Creek rises in the rural/residential suburb of Denham Court, east south-east of Leppington, within the Liverpool local government area  From here the creek flows in a northerly direction under Camden Valley Way towards Hoxton Park, and its junction with Hinchinbrook Creek  Substantial residential development has occurred in these areas, particularly to the west of Cowpasture Road  A number of detention basins have also been constructed in conjunction with the development 
The Ingham's poultry farm also occupies a significant landholding in the area  Below Hoxton Park Road, Cabramatta Creek starts to flow in an easterly direction the Fairfield local government area, towards its confluence with the Georges River, to the east of Warwick Farm  A more prominent creek "corridor", up to 200 metres (660 ft) wide, becomes more evident throughout the lower catchment  This primarily consists of public open space, playing fields and golf courses  The Elouera Nature Reserve, which is an important pocket of native bushland, also forms part of this corridor 
Cabramatta Creek flows through established residential suburbs, including Miller, Cartwright, Sadlier, Ashcroft, Liverpool, Mount Pritchard and Warwick Farm  Major transport routes that cross the catchment includes Hoxton Park Road, Elizabeth Drive, Orange Grove Road (the Cumberland Highway), the Hume Highway and the Main Southern railway line  The catchment area of the creek is approximately 74 square kilometres (29 sq mi), and within the catchment area are the Cabramatta Creek, Hinchinbrook Creek, Maxwells Creek, and Brickmakers Creek The area around the creek was home to the Darug Aboriginal people  European settlement began on the site in the 1790s when they found good quality soil 
In the area surrounding Cabramatta Creek is a large flying fox population; located behind the Sunnybrook Motel and called the Cabrammatta Creek Flying Fox Reserve A concrete beam road bridge that carries the Hume Highway over Cabramatta Creek, constructed in 1951 and commonly known as Ireland's Bridge, is listed on the New South Wales State Heritage Register 
Passage 15:
Little River (Wingecarribee)
The Little River, a watercourse that is part of the Hawkesbury-Nepean catchment, is located in the Southern Highlands region of New South Wales, Australia 

Course and features
The Little River rises south southeast of the locality of Wills Hill, near Robertson, and flows generally north before reaching its confluence with the Dudewaugh Creek, a tributary of the Burke River within the Upper Nepean River catchment  The course of the river is approximately 8 kilometres (5 0 mi) 

See also
List of rivers of New South Wales (L–Z)
List of rivers of Australia
Rivers of New South Wales
Passage 16:
Cup and Saucer Creek
Cup and Saucer Creek, an urban watercourse of the Cooks River catchment, is located in the Canterbury-Bankstown region of Sydney, in New South Wales, Australia 

Course and features
Cup and Saucer Creek rises in Canterbury local government area, near Wiley Park railway station and flows in an east north-easterly direction through the suburbs of Roselands, Kingsgrove and Clemton Park, where it makes its confluence with the Cooks River, within the suburb of Earlwood  The upper reaches of the creek are a piped drainage system, which becomes part drain and part creek in the lower reaches  The Cup and Saucer Creek Catchment Management Study by the Water Board in 1992 showed extensive toxic organics in the form of polycyclic aromatic hydrocarbons and organochlorines The creek is so named because of sandstone formations in the former bed of the creek A concrete culvert over Bexley Road constructed in 1920 is listed on the NSW State Heritage Register 
Passage 17:
Lansdowne River
Lansdowne River, a watercourse of the Manning River catchment, is located in the Mid North Coast district of New South Wales, Australia 

Course and features
Lansdowne River rises below Mount Gibraltar in the Gibraltar Range, north northwest of Upper Lansdowne, and flows generally southeast before reaching its confluence with the Northern Arm of the Manning River, near Coopernook  The river descends 740 metres (2,430 ft) over its 51 kilometres (32 mi) course The Pacific Highway crosses the Lansdowne River south-east of Coopernook 

See also
Rivers of New South Wales
List of rivers of New South Wales (L–Z)
List of rivers of Australia
Passage 18:
Doghole River
The Doghole River is a river in the Unorganized Part of Kenora District in Northwestern Ontario, Canada  The river is part of the James Bay drainage basin  It flows from Doghole Lake, where the outlet is part of the Mishkeegogamang First Nation Osnaburgh Indian Reserve No  63B, to the northeast shore of Lake St  Joseph; oddly, the mouth is not on Doghole Bay, adjacent to the east  Lake St  Joseph is the source of the Albany River, which flows to James Bay 
Passage 19:
Staaten River
The Staaten River is a river in northern Queensland, Australia, rising in the Great Dividing Range and flowing northwest into the Gulf of Carpentaria 

Location and features
The river rises of the western slopes of the Great Dividing Range approximately 200 kilometres (120 mi) west of Cairns  The river flows generally northwest to the Staaten River National Park and then west, joined by eleven minor tributaries before reaching its mouth and emptying into the Gulf of Carpentaria  From source to mouth the river's waters overflow into intertwining lagoons that create an enormous wetland sanctuary for a vast array of unique wildlife and plants  When the rains of the wet season cease, the Staaten River retreats from the floodplains and wetlands and becomes little more than a thread trickling down wide sand banks and a string of important lagoon refuges  The river descends 220 metres (720 ft) over its 383-kilometre (238 mi) course There is very little development in the catchment, with grazing being the most common activity, and there are no major water storage facilities on the river  The river is navigable for 17 kilometres (11 mi) upstream until sand and rock bars are found  Dinah Island, located about 15 kilometres (9 mi) inland, is a small cattle property and at times provides short term accommodation for fishing enthusiasts 

Conservation and cultural values
The Staaten River catchment is one of Australia's last great wilderness areas  With little agricultural development, scant road access, and thriving forests and wildlife, it is a truly wild river system  The river straddles both the Cape York Peninsula and Gulf Country regions  Characterised by the replenishing floods of the wet season and an extensive network of lagoon refuges during the dry season, the river system is known for its excellent saratoga and barramundi fishing and saltwater crocodiles, one of Australia's best known animals 
The wet season is characterized by a large congregation of waterbirds from all over Australia and as far away as China and Russia   This birds live in the abundant waters of places like the huge Inkerman-Gilbrath Wetland, near the mouth of the catchment  The coastal margin of the Staaten River forms part of the Southeast Karumba Plan wetland aggregation, which is the best developed coastal wetland system in Queensland and provides critical habitat and breeding grounds for birds, fish, and other native wildlife  The Staaten River National Park in this area, covering around 467,000 hectares (1,150,000 acres), is one of Australia's largest and most remote national parks 
The Staaten Wild River Area covers about 25,700 square kilometres (9,900 sq mi) at the western base of Cape York Peninsula  The area contains the catchments of the Staaten River, Vanrook Creek, and ten major tributaries   The purpose of the wild river declaration is to "manage future development activity in the wild river area to ensure the wild river natural values are preserved" 

Threats
The Staaten River is remote and currently there is little demand for water extraction in this area  The major present threat in this area is cattle grazing   If not managed sustainably, cattle can cause major soil erosion, trample vegetation, and pollute river systems  There are also minor infestations of the invasive weeds such as rubber-vine in the Staaten River  Wild River protection, as well as the Indigenous Wild River Ranger program, will help address these impacts 

Indigenous heritage
The traditional owners of the upper catchment area are the Kunjen people The Agwamin, Kutjar, Koknar, Kunjen and Kokoberrin people are the traditional owners of the Staaten River catchment area and maintain strong cultural and spiritual connections with the land and rivers  The traditional ecological knowledge and health of these communities is in turn critical to the ongoing health of this wild river system 

Etymology
The river was first named by Dutch sea explorer Jan Carstensz in 1623  It is named after the States General, the parliament of the Netherlands 

See also

List of rivers of Australia § Queensland
Passage 20:
Yukon River
The Yukon River is a major watercourse of northwestern North America  From its source in British Columbia, Canada, it flows through Canada's territory of Yukon (itself named after the river)  The lower half of the river continues westward through the U S  state of Alaska  The river is 3,190 kilometres (1,980 mi) long and empties into the Bering Sea at the Yukon–Kuskokwim Delta  The average flow is 6,400–7,000 m3/s (230,000–250,000 cu ft/s)  The total drainage area is 833,000 km2 (321,500 sq mi), of which 323,800 km2 (125,000 sq mi) lies in Canada  The total area is more than 25% larger than Texas or Alberta 
The longest river in Alaska and Yukon, it was one of the principal means of transportation during the 1896–1903 Klondike Gold Rush  A portion of the river in Yukon—"The Thirty Mile" section, from Lake Laberge to the Teslin River—is a national heritage river and a unit of Klondike Gold Rush International Historical Park  Paddle-wheel riverboats continued to ply the river until the 1950s, when the Klondike Highway was completed  After the purchase of Alaska by the United States in 1867, the Alaska Commercial Company acquired the assets of the Russian-American Company and constructed several posts at various locations on the Yukon River 
The Yukon River has a recent history of pollution from military installations, dumps, wastewater, and other sources  However, the Environmental Protection Agency does not list the Yukon River among its impaired watersheds, and water-quality data from the U S  Geological Survey shows relatively good levels of turbidity, metals, and dissolved oxygen   The Yukon and Mackenzie rivers have much higher suspended sediment concentrations than the great Siberian Arctic rivers The Yukon River Inter-Tribal Watershed Council, a cooperative effort of 70 First Nations and tribes in Alaska and Canada, has the goal of making the river and its tributaries safe to drink from again by supplementing and scrutinizing government data 

Name
The name Yukon, or ųųg han, is a contraction of the words in the Gwich'in phrase chųų gąįį han, which means white water river and refers to "the pale colour" of glacial runoff in the Yukon River   The contraction is Ųųg Han, if the /ųų/ remains nasalized, or Yuk Han, if there is no vowel nasalization   In the 1840s, different tribes had different opinions as to the literal meaning of Yukon   In 1843, the Holikachuks had told the Russian-American Company that their name for the river was Yukkhana and that this name meant big river   However, Yukkhana does not literally correspond to a Holikachuk phrase that means big river   Then, two years later, the Gwich'ins told the Hudson's Bay Company that their name for the river was Yukon and that the name meant white water river   White water river in fact corresponds to Gwich'in words that can be shortened to form Yukon   Because the Holikachuks had been trading regularly with both the Gwich’ins and the Yup'iks, the Holikachuks were in a position to borrow the Gwich'in contraction and to conflate its meaning with the meaning of Kuig-pak [River-big], which is the Yup'ik name for the same river   For that reason, the documentary evidence suggests that the Holikachuks had borrowed the contraction Ųųg Han [White Water River] from Gwich'in, and erroneously assumed that this contraction had the same literal meaning as the corresponding Yup'ik name Kuig-pak [River-big] 
The Lewes River is the former name of the upper course of the Yukon, from Marsh Lake to the confluence of the Pelly River at Fort Selkirk 

Course
The generally accepted source of the Yukon River is the Llewellyn Glacier at the southern end of Atlin Lake in British Columbia  Others suggest that the source is Lake Lindeman at the northern end of the Chilkoot Trail  Either way, Atlin Lake flows into Tagish Lake (via the Atlin River), as eventually does Lake Lindeman after flowing into Bennett Lake  Tagish Lake then flows into Marsh Lake (via the Tagish River)  The Yukon River proper starts at the northern end of Marsh Lake, just south of Whitehorse  Some argue that the source of the Yukon River should really be Teslin Lake and the Teslin River, which has a larger flow when it reaches the Yukon at Hootalinqua  The upper end of the Yukon River was originally known as the Lewes River until it was established that it actually was the Yukon  North of Whitehorse, the Yukon River widens into Lake Laberge, made famous by Robert W  Service's "The Cremation of Sam McGee"  Other large lakes that are part of the Yukon River system include Kusawa Lake (into the Takhini River) and Kluane Lake (into the Kluane and then White River) 
The river passes through the communities of Whitehorse, Carmacks, (just before the Five Finger Rapids) and Dawson City in Yukon, and crossing Alaska into Eagle, Circle, Fort Yukon, Stevens Village, Rampart, Tanana, Ruby, Galena, Nulato, Grayling, Holy Cross, Russian Mission, Marshall, Pilot Station, St  Marys (which is accessible from the Yukon at Pitkas Point), and Mountain Village  After Mountain Village, the main Yukon channel frays into many channels, sprawling across the delta  There are a number of communities after the "head of passes," as the channel division is called locally: Nunum Iqua, Alakanuk, Emmonak, and Kotlik  Of those delta communities, Emmonak is the largest with roughly 760 people in the 2000 census  Emmonak's gravel airstrip is the regional hub for flights 

Hazards
Navigational obstacles on the Yukon River are the Five Finger Rapids and Rink Rapids downstream from Carmacks 

Bridges
Despite its length, there are only four vehicle-carrying bridges across the river, listed from upstream to downstream:

The Lewes Bridge, north of Marsh Lake, Yukon, on the Alaska Highway;
The Robert Campbell Bridge, which connects the Whitehorse suburb of Riverdale to the downtown area;
The Yukon River Bridge in Carmacks, Yukon, on the Klondike Highway; and
The Yukon River Bridge, north of Fairbanks, Alaska on the Dalton Highway A car ferry crosses the river at Dawson City in the summer; it is replaced by an ice bridge over the frozen river during the winter  Plans to build a permanent bridge were announced in March 2004, although they are currently on hold because bids came in much higher than budgeted 
There are also two pedestrian-only bridges in Whitehorse, as well as a dam across the river and a hydroelectric generating station  The construction of the dam flooded the White Horse Rapids, which gave the city its name, and created Schwatka Lake 
Transportation is also performed along the river in summer by barge, enabling heavy goods, oil, and vehicles to be transported to communities along the Yukon, Tanana, Innoko, and Koyukuk rivers  This service is performed by Ruby Marine and reaches Tanana on the Yukon River and Nenana on the Tanana River 

Geography and ecology
Some of the upper slopes of this watershed (e g  Nulato Hills) are forested by Black Spruce  This locale near the Seward Peninsula represents the near westernmost limit of the Black Spruce, Picea mariana, one of the most widespread conifers in northern North America 
The river flows into several parklands and refuges including:

Innoko National Wildlife Refuge
Nowitna National Wildlife Refuge
Yukon-Charley Rivers National Preserve
Yukon Delta National Wildlife Refuge
Yukon Flats National Wildlife Refuge

Discharge
Yukon at Pilot Station (121 miles upstream of mouth) minimum, average and maximum discharge

Fisheries
The Yukon River is home to one of the longest salmon runs in the world  Each year Chinook, coho, and chum salmon return to their terminal streams in Alaska, the Yukon Territory, and British Columbia  The Chinook have the longest journey, with an estimated 35–50% bound for Canada  As salmon do not eat during their spawning migration, Yukon River salmon must have great reserves of fat and energy to fuel their thousands-mile-long journey  As a result, Yukon River salmon are noted for their especially rich and oily meat 
The villages along the Yukon have historically relied on and continue to rely on salmon for their cultural, subsistence, and commercial needs  Salmon are traditionally dried, smoked, and frozen for both human and sled dog consumption  Common methods of fishing on the Yukon include set gillnets, drift nets, dip nets, and fish wheels  The preference of certain gear is largely dependent on the river's varied characteristics in different areas  Some parts of the river do not have eddies to make set-nets successful, whereas in other places the tributaries are small enough to make drifting impractical 
Over the last 20 years salmon recruitment, the number of returning adults, has taken several shocks  The late 1980s, 1990s, and 2000s have been marked by radically reduced runs for various salmon species  The United States Department of Commerce issued a Federal Disaster Declaration for the 2008 and 2009 Commercial Chinook Yukon River fisheries, calling for the complete closure of commercial fishing along with restrictions on subsistence fishing  The root cause of these poor returns remains debated, with questions about the effects of climate change on ocean food-supply & disease prevalence in returning adults, the methods of fishing used on the river, and the effects of the Bering Sea Pollock trawl fleet on food supply and salmon bycatch  In 2010, the Alaska Department of Fish & Game's Board of Fisheries issued the first-ever restriction for net mesh size on the Yukon, reducing it to 7 5 inches (190 mm) Various organizations are involved to protect healthy salmon runs into the future  The Yukon River Drainage Fisheries Association was formed in 1990 by a consensus of fishers representing the entire drainage in response to recent disaster years  Its organizational goals include giving voice to the village fishers that have traditionally managed these resources, enabling communication between fishers and fishery managers, and helping to preserve the ecological integrity of salmon runs and local cultures' Traditional Ecological KnowledgeIn March 2001, the U S  & Canadian governments passed the Yukon River Salmon Agreement to better manage an internationally shared resource and ensure that more Canadian-originated salmon return across the border  The agreement is implemented through the Yukon River Panel, an international body of 12 members, equal-parts American and Canadian, that advises managers of Yukon River fisheries concerning restoration, conservation, and coordinated management Tribal organizations such as the Association of Village Council Presidents (AVCP), Council of Athabascan Tribal Governments (CATG), and Tanana Chiefs Conference (TCC) work to sustain Yukon River salmon to promote healthy people, cultures, and communities 

Tributaries
Yukon Territory
Takhini River
Big Salmon River
Little Salmon River (Yukon)
Nordenskiold River
Teslin River
Pelly River
Macmillan River
Stewart River
Nadaleen River
Lansing River
Hess River
Mayo River
McQuesten River
White River
Donjek River
Kluane River
Nisling River
Beaver Creek
Sixtymile River
Indian River
Klondike River
Fortymile River

Alaska
Tatonduk River
Seventymile River
Nation River
Kandik River
Charley River
Porcupine River
(tributaries in the Yukon)Miner tributaries
Fishing Branch
Bell River
Eagle River
Rock River (Yukon)
Driftwood River (Yukon)
Old Crow River
Bluefish River(tributaries in Alaska)Coleen River
Black River
Wood River
Bear Mountain Creek
Mountain Creek
Chandalar Creek
Sheenjek River
Sheenjek River East Fork
Koness River
Eskimo Creek
Christian River
Chandalar River
East Fork Chandalar River
Junjik River
Wind River
Middle Fork Chandalar River
North Fork Chandalar River
West Fork Chandalar River
Marten Creek
Birch Creek
Hadweenzic River
Beaver Creek
Hodzana River
Dall River
Ray River
Big Salt River
Hess Creek
Garnet Creek
Fish Creek
Texas Creek
Coal Creek
Tanana River
Nabesna River
Chisana River
Tetlin River
Goodpaster River
Delta River
Salcha River
Chena River
Wood River
Nenana River
Tolovana River
Kantishna River
NC Creek
Tozitna River
Bluebell Creek
Dagislakhna Creek
Banddana Creek
Blind River
Bering Creek
Nowitna River
Sulatna River
Big Creek
Beaver Creek
Glacier Creek
Melozitna River
Black Sand Creek
Little Melozitna River
Ruby Slough
Yuki River
East Fork Yuki River
Kala Creek
Kelly Creek
Galena Creek
Bishop Creek
Koyukuk River
Workyard Creek
Gisasa River
Kateel River
Dulbi River
Huslia River
Nulitna River
Tom Cook Slough
Billy Hawk Creek
Cutoff Slough
Hogatza River
Clear Creek
Batza River
Matthews Slough
Little Indian River
Indian River
Calamity Creek
Pocahontas Creek
Kanuti River
Discovery Creek
Alatna River
Siruk Creek
South Fork Koyokouk River
Jim River
Jane Creek
John River
North Fork Koyukuk River
Nulato River
Khotol River
Anvik River
Bonasila River
Stuyahok River
Innoko River
Paimiut Slough
Reindeer River
Iditarod River
Yetna River
First Chance Creek
Mud River
Dishna River
Coffee Creek
Tolstoi Creek
Madison Creek
Mastodon Creek
Hurst Creek
Taft Creek
Finland Creek
Scandinavian Creek
North Fork Innoko River
Tango Creek
West Fork North Fork Innoko River
Colorado Creek
Kako Creek
Engineer Creek
Reindeer River
Atchuelinguk River
Andreafsky River
Kashunuk River (distributary)

List of major tributaries
The main river and tributaries are (sorted in order from the mouth heading upstream):

In media
The Yukon River features as the setting for the 2015 National Geographic Channel series Yukon River Run 
The industrial metal band Lindemann wrote a song named "Yukon" on their first album Skills in Pills 

See also
Alaska salmon fishery
List of longest rivers of Canada
List of longest rivers of the United States (by main stem)
List of rivers of Alaska
List of Yukon rivers
Steamboats of the Yukon River



ground_truth: Thaba Putsoa

prompt_front: Answer the question based on the given passages. Only give me the answer and do not output any other words.

Question: What undertaking included the person who discovered that the number of protons in each element's atoms is unique?

The following are given passages.
Context 4:  2 on the Billboard Christian Songs chart and also spent a third week at No  1 on the Billboard Christian Digital Songs chart; the song had spent 425 weeks on the chart at that point, the longest run of any song in the chart's history  "I Can Only Imagine" peaked at No  1 on the Christian Songs chart on March 31, 2018, and spent three weeks at the top spot  It also peaked at No  10 on the Billboard Digital Songs chart and ranked at No  8 on the 2018 year-end Christian Songs chart In April 2010, "I Can Only Imagine" was certified platinum by the RIAA, signifying sales of over 1 million digital downloads  It was the first single by any artist in the Christian music genre to go platinum  The song was certified double platinum in September 2014, triple platinum in June 2018, and quadruple platinum in September 2019  As of March 2018, it has sold 2 5 million copies, making it the best-selling Christian single of all time 

Music video
A music video was released for "I Can Only Imagine"  According to Millard, the video's inspiration came from seeing people holding empty picture frames at their concerts, symbolizing their deceased loved ones  Millard said that the "I've had so many people after a show pull out a picture of someone they've lost  These people embrace these photos and I just thought how can we tap into that"  The video features everyday people as well as several music artists including Michael Tait, Tammy Trent, Bob Herdman, and Jesse Katina, each holding an empty picture frame to signify their loss of a loved one; as the video progresses, they are holding pictures of their loved ones including Millard with his father's photograph 

Live performances
Despite including "I Can Only Imagine" on The Worship Project, MercyMe initially did not perform the song in concerts because they felt it did not fit with the rest of the record  The band's first performance of the song did not come until the summer after the release of The Worship Project at a summer camp at the request of a camp counselor  The band has played the song at every show since as of February 2009 MercyMe's 2004 concert tour (the Imagine Tour) and 2018–19 tour (the Imagine Nation Tour) both took their name from the song MercyMe performed "I Can Only Imagine" at the 33rd GMA Dove Awards, with an accompanying "inspiring video that underscored the emotional and inspirational power of song"  The band also performed the song at the 40th GMA Dove Awards, held on April 23, 2009, in a medley with "Finally Home"  At the 2017 National Prayer Breakfast, MercyMe performed the song with President Donald Trump in attendance  In March 2018, MercyMe performed "I Can Only Imagine" live on Fox & Friends to promote the film 

Other versions
Both an acoustic and live version of "I Can Only Imagine" were included in the Platinum edition of Almost There, which was released in August 2006  MercyMe released a new recording of the song on their iTunes Originals album, which was released in March 2008  On their compilation album 10, MercyMe released a new recording of the song featuring the London Session Orchestra as well as a live version  For their 2018 compilation album I Can Only Imagine: The Very Best of MercyMe, released to commemorate the release of the movie, the band recorded an updated recording titled "I Can Only Imagine (The Movie Session)", which peaked at No  19 on the Billboard Christian Songs chart "I Can Only Imagine" has been covered by several artists  In 2002, Amy Grant released her reworked version of the song, titled "Imagine" and paired with "Sing the Wondrous Love of Jesus", on her album Legacy    Hymns and Faith  Country singer Jeff Carson's 2003 cover peaked at No  50 on the Country Songs chart, and in 2014, gospel singer Tamela Mann's cover of the song spent 13 weeks atop the Billboard Gospel Songs chart  In May 2017, Aliyah Moulden, the third-place finisher on the 12th season of the reality competition show The Voice, performed the song on the show; her version debuted and peaked at No  4 on the Billboard Christian Songs chart, selling 15,000 copies in its first week and spending two weeks on the chart in total 

Track listing
CD release
"I Can Only Imagine" – 4:06 (Bart Millard)
"Word of God Speak" – 3:07 (Peter Kipley, Millard)

Personnel
(Credits from the album liner notes)MercyMe

Bart Millard – vocals
Jim Bryson – keyboards
Nathan Cochran – bass guitar, background vocals
Mike Scheuchzer – guitar, background vocals
Robby Shaffer – drumsAdditional performers

Paltrow Performance Group – stringsTechnical

Julian Kindred – engineer
Pete Kipley – producer, programming
Skye McCaskey  – engineer
Salvo – mixing
Shane Wilson – mixing

Release and radio history
Charts and certifications
Certifications
Passage 10:
Minipops
Minipops is a television series broadcast in 1983 on Channel 4 in the United Kingdom  Designed primarily for younger viewers, it consisted of music performances on a brightly coloured set featuring preteen children singing then-contemporary pop music hits and older classics  The children were usually made to look like the original performers, including clothing and make-up  Controversy over children singing songs that often contained a subtext of adult content (in adult costumes and make-up) led to the show's cancellation after one series 

History
Minipops was the brainchild of Martin Wyatt, who created a new child group from London called the MiniPops and released an album in 1982 which reached the top 30 in the UK and Europe  This resulted in a French record label releasing a single from the album, "Stupid Cupid",  which was sung by Martin Wyatt's young daughter Jo  The song reached number 1 in France, knocking "Ebony and Ivory" off the top spot Head of Entertainment Cecil Korer at Channel 4 and record producer Mike Mansfield embraced the idea of producing a TV show around the MiniPops; Korer believed it would boost and broaden the group's audience appeal  On 4 July 1982, thousands of amateur child performers from across Britain descended on a London theatre for the audition in a search to find additional children to sing and star in the television show with the original five members of the group 

Criticism
The programme began attracting criticism from commentators in the British media for the portrayal of children in this manner (one caller on Channel 4's Right to Reply programme stated, "Minipops should be called MiniWhores  Are you people out of your mind?") 

Discography
Seven albums were produced and released in the UK, Europe and Canada 

Albums
Before the television show:

The Mini Pops (1982)After the television show:

We're the Mini Pops (1983)
Christmas (1984)
Let's Dance (1984)
Wanna Have Fun (1985)
Magic Juke Box (1986)
Rocket to the Stars (1989)In Canada We're the Mini Pops was successful, becoming the third-highest-selling album in Canada at the time  This prompted the Minipops to hold a three-week tour in 1983, enjoying controversy-free success A number of singles were released across Europe 

See also
Kidz Bop
Mini Pop Kids
Passage 11:
Adult contemporary music
Adult contemporary music (AC) is a form of radio-played popular music, ranging from 1960s vocal and 1970s soft rock music to predominantly ballad-heavy music of the present day, with varying degrees of easy listening, pop, soul, R&B, quiet storm and rock influence  Adult contemporary is generally a continuation of the easy listening and soft rock style that became popular in the 1960s and 1970s with some adjustments that reflect the evolution of pop/rock music Adult contemporary tends to have lush, soothing and highly polished qualities where emphasis on melody and harmonies is accentuated  It is usually melodic enough to get a listener's attention, and is inoffensive and pleasurable enough to work well as background music  Like most of pop music, its songs tend to be written in a basic format employing a verse–chorus structure  The format is heavy on romantic sentimental ballads which mostly use acoustic instruments (though bass guitar is usually used) such as acoustic guitars, pianos, saxophones, and sometimes an orchestral set  The electric guitars are normally faint and high-pitched  However, recent adult contemporary music may feature synthesizers (and other electronics, such as drum machines) An AC radio station may play mainstream music, but it usually excludes hip-hop and some forms of dance-pop and teen pop, as these are less popular among adults, the target demographic  AC radio often targets the 25–44 age group, the demographic that has received the most attention from advertisers since the 1960s  A common practice in recent years of adult contemporary stations is to play less newer music and more hits of the past, even some songs that never even charted the AC charts   This de-emphasis on new songs slows the progression of the AC chart Over the years, AC has spawned subgenres including "hot AC" (also known as "modern AC"), "soft AC" (also known as "lite AC"), "urban AC" (a softer type of urban contemporary music), "rhythmic AC" (a softer type of rhythmic contemporary), and "Christian AC" (a softer type of contemporary Christian music)  Some stations play only "hot AC", "soft AC", or only one of the variety of subgenres  Therefore, it is not usually considered a specific genre of music; it is merely an assemblage of selected songs from artists of many different genres 

History
1960s: Early roots; easy listening and soft rock
Adult contemporary traces its roots to the 1960s easy listening format, which adopted a 70—80% instrumental to 20–30% vocal mix  A few offered 90% instrumentals, and a handful were entirely instrumental  The easy listening format, as it was first known, was born of a desire by some radio stations in the late 1950s and early 1960s to continue playing current hit songs but distinguish themselves from being branded as "rock and roll" stations  Billboard first published the Easy Listening chart July 17, 1961, with 20 songs; the first number one was "Boll Weevil Song" by Brook Benton  The chart described itself as "not too far out in either direction" Initially, the vocalists consisted of artists such as Frank Sinatra, Doris Day, Johnny Mathis, Connie Francis, Nat King Cole, Perry Como, and others  The custom recordings were usually instrumental versions of current or recent rock and roll or pop hit songs, a move intended to give the stations more mass appeal without selling out  Some stations would also occasionally play earlier big band-era recordings from the 1940s and early 1950s After 1965, differences between the Hot 100 chart and the Easy Listening chart became more pronounced  Better reflecting what middle of the road stations were actually playing, the composition of the chart changed dramatically  As rock music continued to harden, there was much less crossover between the Hot 100 and Easy Listening chart than there had been in the early half of the 1960s  Roger Miller, Barbra Streisand and Bobby Vinton were among the chart's most popular performers One big impetus for the development of the AC radio format was that, when rock and roll music first became popular in the mid-1950s, many more conservative radio stations wanted to continue to play current hit songs while shying away from rock  These middle of the road (or "MOR") stations also frequently included older, pre-rock-era adult standards and big band titles to further appeal to adult listeners who had grown up with those songs 
Another big impetus for the evolution of the AC radio format was the popularity of easy listening or "beautiful music" stations, stations with music specifically designed to be purely ambient  Whereas most easy listening music was instrumental, created by relatively unknown artists, and rarely purchased (especially as singles, although Jackie Gleason's beautiful music albums sold well in the 1950s), AC was an attempt to create a similar "lite" format by choosing certain tracks (both hit singles and album cuts) of popular artists 

1970s: Soft rock forms as a radio format
By the late 1960s hard rock had been established as one of the rock genres leading hard rock and soft rock to became distinct popular forms in the rock scene, and as major radio formats in the US  Soft rock was often derived from folk rock, using acoustic instruments and putting more emphasis on melody and harmonies  Major artists included Carole King, Cat Stevens, James Taylor and Bread In the early 1970s, softer songs by The Carpenters, Anne Murray, John Denver, Barry Manilow, and even Barbra Streisand, began to be played more often on "Top 40" radio  Top 40 radio stations played the Top 40 hits regardless of genre   As the texture of much of the music played on Top 40 radio began to soften, the Hot 100 and Easy Listening/AC charts became more similar  Easy Listening radio began playing songs by artists who had begun in other genres, such as rock and roll or R&B  Much of the music recorded by singer-songwriters such as Diana Ross, James Taylor, Carly Simon, Carole King and Janis Ian got as much, if not more, airplay on AC stations than on Top 40 stations  AC stations also began playing softer songs by Elvis Presley, Linda Ronstadt, Elton John, Rod Stewart, Billy Joel, and other rock-based artists  Soon after, the adult contemporary format began evolving into the sound that later defined it, with rock-oriented acts as Chicago and the Eagles, becoming associated with the format  In addition, several early disco songs, did well on the Adult Contemporary format 
Soft rock reached its commercial peak in the mid-to-late 1970s with acts such as Toto, England Dan & John Ford Coley, Air Supply, Seals and Crofts, Dan Fogelberg, America and the reformed Fleetwood Mac, whose Rumours (1977) was the best-selling album of the decade  By 1977, some radio stations, notably New York's WTFM and NBC-owned WYNY, and Boston's WEEI, had switched to an all-soft rock format  As Softrock 103, WEEI was famous for its promotional campaigns, featuring slogans such as "Joni, without the baloni " and "The Byrds, without the nyrds "  However, different forms of popular music  targeted to different demographic groups, such as disco vs  hard rock, began to emerge in the late-1970s  This led to specialized radio stations that played specific genres of music, and generally followed the evolution of artists in those genres 

1980s: Adult contemporary succeeds as radio format
On April 7, 1979, the Easy Listening chart officially became known as Adult Contemporary, and those two words have remained consistent in the name of the chart ever since  Adult contemporary music became one of the most popular radio formats of the 1980s  The growth of AC was a natural result of the generation that first listened to the more "specialized" music of the mid-late 1970s growing older and not being interested in the heavy metal and rap/hip-hop music that a new generation helped to play a significant role in the Top 40 charts by the end of the decade 
Mainstream AC itself has evolved in a similar fashion over the years; traditional AC artists such as Barbra Streisand, the Carpenters, Dionne Warwick, Barry Manilow, John Denver, and Olivia Newton-John found it harder to have major Top 40 hits as the 1980s wore on, and due to the influence of MTV, artists who were staples of the Contemporary Hit Radio format, such as Richard Marx, Michael Jackson, Bonnie Tyler, George Michael, Phil Collins, Laura Branigan and Journey began crossing over to the AC charts with greater frequency  Collins has been described by AllMusic as "one of the most successful pop and adult contemporary singers of the '80s and beyond"  However, with the combination of MTV and AC radio, adult contemporary appeared harder to define as a genre, with established soft-rock artists of the past still charting pop hits and receiving airplay alongside mainstream radio fare from newer artists at the time 
The amount of crossover between the AC chart and the Hot 100 has varied based on how much the passing pop music trends of the times appealed to adult listeners  Not many disco or new wave songs were particularly successful on the AC chart during the late 1970s and early 1980s, and much of the hip-hop and harder rock music featured on CHR formats later in the decade would have been unacceptable on AC radio 
Although dance-oriented, electronic pop and ballad-oriented rock dominated the 1980s, soft rock songs still enjoyed a mild success thanks to Sheena Easton, Amy Grant, Lionel Richie, Christopher Cross, Dan Hill, Leo Sayer, Billy Ocean, Julio Iglesias, Bertie Higgins, and Tommy Page  No song spent more than six weeks at No  1 on this chart during the 1980s, with nine songs accomplishing that feat  Two of these were by Lionel Richie, "You Are" in 1983 and "Hello" in 1984, which also reached No  1 on the Hot 100 
In 1989, Linda Ronstadt released Cry Like a Rainstorm, Howl Like the Wind, described by critics as "the first true Adult Contemporary album of the decade", featuring American soul singer Aaron Neville on several of the twelve tracks  The album was certified Triple Platinum in the United States alone and became a major success throughout the globe  The Grammy Award-winning singles, "Don't Know Much" and "All My Life", were both long-running No  1 Adult Contemporary hits  Several additional singles from the disc made the AC Top 10 as well  The album won over many critics in the need to define AC, and appeared to change the tolerance and acceptance of AC music into mainstream day to day radio play 

1990s: Subgenre formations/radio crossovers
The early 1990s marked the softening of urban R&B in the shape of new jack swing, at the same time alternative rock emerged and traditional pop saw a significant resurgence  This in part led to a widening of the market, not only allowing to cater to more niche markets, but it also became customary for artists to make AC-friendly singles  At the same time, the genre began adopting elements from hard rock as tastes were shifting towards louder music, while AC stations in general began playing more rock acts  "Softer" features such as light instrumental music (carried over from the beautiful music format—many AC stations carried the format until the early 1970s), new age songs and most pre-1964 artists were gradually phased out from AC radio throughout the early to mid-1990s 
Unlike the majority of 1980s mainstream singers, the 1990s mainstream pop/R&B singers such as All-4-One, Boyz II Men, Christina Aguilera, Backstreet Boys and Savage Garden generally crossed over to the AC charts  Latin pop artists such as Lynda Thomas, Ricky Martin, Marc Anthony, Selena, Enrique Iglesias and Luis Miguel also enjoyed success in the AC charts 
In addition to Celine Dion, who has had significant success on this chart, other artists with multiple number ones on the AC chart in the 1990s include Mariah Carey, Phil Collins, Michael Bolton, Bryan Adams, Whitney Houston and Shania Twain  Newer female Adult album alternative singer-songwriters such as Sarah McLachlan, Natalie Merchant, Jewel, Melissa Etheridge and Sheryl Crow also broke through on the AC chart during this time In 1996, Billboard created a new chart called Adult Top 40, which reflects programming on radio stations that exists somewhere between "adult contemporary" music and "pop" music  Although they are sometimes mistaken for each other, the Adult Contemporary chart and the Adult Top 40 chart are separate charts, and songs reaching one chart might not reach the other  In addition, hot AC is another subgenre of radio programming that is distinct from the Hot Adult Contemporary Tracks chart as it exists today, despite the apparent similarity in name 
In response to the pressure on Hot AC, a new kind of AC format cropped up among American radio recently  The urban adult contemporary format (a term coined by Barry Mayo) usually attracts a large number of African Americans and sometimes Caucasian listeners through playing a great deal of R&B (without any form of rapping), gospel music, classic soul and dance music (including disco) 
Another format, rhythmic AC, in addition to playing all the popular hot and soft AC music, past and present, places a heavy emphasis on disco as well as 1980s and 1990s dance hits, such as those by Amber, and Black Box, and includes dance remixes of pop songs, such as the Soul Solution mix of Toni Braxton's "Unbreak My Heart" 
In its early years of existence, the smooth jazz format was considered to be a form of AC, although it was mainly instrumental, and related a stronger resemblance to the soft AC-styled music  For many years, George Benson, Kenny G and Dave Koz had all had crossover hits that were played on both smooth jazz and soft AC stations 

2000s–present: AC music goes mainstream and mainstream music goes AC
During the 2000s, the AC market gained an increased presence in the music industry, as its radio formats were popular nationwide—Smooth jazz and "Urban AC" stations were ubiquitous in the East Coast, while Soft rock and "adult standards" stations were common in the Midwest, and pop-oriented "Hot AC" and "world music"/Hispanic AC stations were easily found in the West Coast and the "Sun Belt"  This led to the presence of numerous genres on the AC charts, often crossing to the "pop" charts, winning over many critics in the need to define AC, and increased the tolerance and acceptance of AC music into mainstream day-to-day radio play 
Josh Groban's single "You Raise Me Up" and Michael Bublé's cover of "Fever" are often cited as key examples of the high production values and ballad-heavy sound that defined 2000s-era AC, often dubbed as "jazz-pop", heavily carrying classical, jazz and traditional pop influences  Artists such as Nick Lachey, James Blunt, Jamie Cullum, John Mayer, Jason Mraz, Norah Jones, Diana Krall, Amy Winehouse and Susan Boyle also achieved great success during this period  During most of the 2000s, country music/countrypolitan musicians such as Kelly Clarkson, Clay Aiken, Billy Joel, Garth Brooks, Shania Twain, LeAnn Rimes and Carrie Underwood scored hits on soft AC, particularly in Southern states  A popular trend in the late 1990s and 2000s was remixing dance music hits into adult contemporary ballads, especially in the US, (for example, the "Candlelight Mix" versions of "Heaven" by DJ Sammy, "Listen To Your Heart" by D H T , and "Everytime We Touch" by Cascada) 
Key to the success of AC in the 2000s was the 25–34 demographic which had outgrown the pop music offerings of the time, most new rock became too alternative and harsh for AC radio and most new pop was now influenced heavily by dance-pop, hip-hop and electronic dance music  At the same time, the music industry also began to focus on older audiences and markets generally considered "niche" 
During the late 2000s, certain pop songs began entering the AC charts instead, generally after having recently fallen off the Hot 100  Adrian Moreira, senior vice president for adult music for RCA Music Group, said, "We've seen a fairly tidal shift in what AC will play"  Rather than emphasizing older songs, adult contemporary now began playing many of the same songs as top 40 and adult top 40, but only after the hits had become established  An article on MTV's website by Corey Moss describes this trend as: "In other words, AC stations are where pop songs go to die a very long death  Or, to optimists, to get a second life " As adult contemporary has long characterized itself as family-friendly, "clean" versions of pop songs began appearing on the AC chart, as were the cases of "Perfect" by P!nk, and "Forget You" by Cee Lo Green, both in 2011 AC radio's shift into more mainstream pop was a result of the changes on the broadcasting landscape following the 2005–2007 economic downturn and eventual recession, as advertisers preferred more profitable chart-based formats, which meant the demise of many AC-based formulas, primarily those aimed at older audiences, with tastes changing towards more modern music among all age groups  Diminishing physical record sales throughout the 2010s also proved a major blow to the AC genre, and there are concerns that the portable people meter, a device being used to determine radio listenership, may be incompatible with AC songs and may not accurately pick up that a person is listening to an AC station because of the pitches and frequencies used in the style Key AC artists of the early to mid-2010s included Bruno Mars, Coldplay, Adele, Arcade Fire, Meghan Trainor, Maroon 5 and Ed Sheeran, featuring a more pop-influenced, uptempo style than the typical AC fare of previous years, also featuring production values reminiscent of the Motown sound and the so-called Wall of Sound that dominated the soul-heavy pop charts of the early 1960s, when the Easy Listening chart was first introduced  The earlier years of the decade also saw alternative and indie rock acts such as Wilco, Feist, The 1975, Imagine Dragons, Mumford & Sons, Of Monsters and Men and The Lumineers quickly becoming AC mainstays, although these were eventually replaced by rhythm-based rock bands such as Panic! at the Disco, Neon Trees, X Ambassadors, Sheppard, Bastille, American Authors, Fitz and the Tantrums, Foster the People, Twenty One Pilots, Walk the Moon and Milky Chance 
During the middle of the decade, newer artists such as CeeLo Green, OneRepublic, Rachel Platten, Christina Perri, Andy Grammer, James Bay, Sara Bareilles, Shawn Mendes, Sia, Sam Smith, Gavin Degraw, Charlie Puth and Colbie Caillat as well as acts that were popular in the 1990s and early 2000s such as Britney Spears and Christina Aguilera were added to the rotation of most AC stations 
As trap music and similar styles of hip-hop began dominating top 40 stations during the last years of the 2010s, AC stations began picking up rhythmic artists like Rihanna, Lady Gaga, Ellie Goulding, Taio Cruz and Pitbull as well as EDM artists like Avicii, Daft Punk, Calvin Harris, David Guetta and Tiesto  Meanwhile, younger artists like Camila Cabello, Justin Bieber, Selena Gomez, Ariana Grande, Nick Jonas and the Jonas Brothers and Halsey began to be featured on AC stations more than on top 40 stations 

Adult contemporary formats
In radio broadcasting, adult contemporary is divided into several sub-formats, each with their own musical direction and demographic targeting  Hot adult contemporary formats generally feature an uptempo rotation of recent hits that appeal to a wide adult audience  A station formatted as "adult contemporary" with no qualifier, also referred to as "mainstream adult contemporary", generally has a similar playlist to hot AC stations, but with a broader rotation of classic hits from past decades Soft adult contemporary formats have a more conservative sound oriented primarily towards adult women, urban AC focuses on R&B and soul music that appeal to African American adults, and rhythmic AC focuses on dance music and other rhythmic genres 

Hot adult contemporary
Hot adult contemporary (hot AC) radio stations play a wide range of the present day's popular music that appeals towards the 18–54 age group; it serves as a middle ground between the youth-oriented contemporary hit radio (CHR) format, and adult contemporary formats (such as "mainstream" and soft AC) that are typically targeted towards a more mature demographic  They generally feature uptempo hit music with wide appeal, such as pop and pop rock songs, while excluding more youth-oriented music such as hip-hop  Recurrents usually reflect familiar and youthful music that adults had grown up with  Likewise, mature material from pop acts such as the Backstreet Boys, Jason Mraz, John Mayer, and Pink have also been prominent within the format The "hot AC" designation began to appear in the 1990s, to describe adult contemporary stations with a more energetic presentation and uptempo sound than their softer counterparts  An early example of the format, Houston's KHMX Mix 96 5, climbed from 14th place in the market to 3rd in the six months after its launch  The station's format and branding was widely replicated by other stations  Many hot AC outlets are among the top stations in their respective market Initially focused more on pop rock, the format has evolved to reflect changes in the composition of this audience; by the mid-2000s, the format had evolved to include more uptempo pop music, while alternative and indie rock crossovers (such as Foster the People, Imagine Dragons, Lovelytheband, and Twenty One Pilots) became more prevalent within the format during the 2010s These developments helped to expand the popularity of the format among younger listeners such as millennials; Nielsen Audio ranked hot AC as the third most-popular format among millennials, behind pop and country music  Of the format's expanding demographic reach, WOMX-FM program director Dana Taylor stated that hot AC stations "may not be the radio station that everybody agrees on, but it's a radio station that everybody goes, 'I'm okay with that' " The increasingly downtempo direction of pop hits in the mid-to-late 2010's also helped to attract additional listeners Hot AC stations typically keep a larger body of recent hits in rotation than those with rigid, chart-driven formats like CHR and urban contemporary  As these stations' playlists have become concentrated towards airing only the current hits at a given time, hot AC airplay can build and sustain a song's popularity over a long-term period  This effect has been credited in helping build an audience for early singles from new acts such as Adele, Rachel Platten ("Fight Song", which gained prominence for its use during Hillary Clinton's 2016 US presidential election campaign), and Max Schneider (whose 2016 single "Lights Down Low", over a year after its original release, became a sleeper hit on the Billboard Mainstream Top 40 and Hot 100 due in part to strong hot AC airplay) The popularity of the hot AC format prompted many mainstream AC stations to add uptempo music to their playlists, while still maintaining a deeper rotation of older hits than hot AC stations 

Modern adult contemporary
Modern adult contemporary refers to AC formats with a stronger lean towards modern rock and pop rock 
In the 1990s and early 2000s, modern AC was typically targeted towards women, with Mike Marino of KMXB in Las Vegas describing the format as reaching "an audience that has outgrown the edgier hip-hop or alternative music but hasn't gotten old and sappy enough for the soft ACs " The format typically focused on female rock acts such as Shawn Colvin, Sheryl Crow, Indigo Girls, Jewel, and Sarah McLachlan, and folk rock-influenced bands such as Counting Crows and The Wallflowers  Today, the format is fairly uncommon, with KTCZ in the Minnesota Twin Cities being one of the few modern AC stations left 

Soft adult contemporary
The Soft adult contemporary format typically targets women 25–54 and at-work listening  Soft AC playlists are generally conservative in comparison to hot AC, focusing on pop and power ballads, soft rock, and other familiar, light hits  Upon its establishment in the 1980s, the soft AC format was positioned as being a more upbeat version of easy listening that would appeal better to a younger audience, mainly by excluding instrumental beautiful music  Easy listening stations had begun shifting to the format out of concern that their existing programming would not appeal to the current generation of listeners In a 1990 article, James Warren of the Chicago Tribune characterized soft AC stations as being "as middle-of-the-road and unthreatening as modern media get", with personalities that were encouraged to be as inoffensive and "low-profile" as possible, and a more conservative music library than hot AC-leaning stations  In particular, Chicago's WLIT did not have its airstaff talk over the beginning and endings of songs (in contrast to the hot AC-leaning WFYR), and played Bob Seger's "We've Got Tonite" but not "Old Time Rock and Roll" (which was part of WTMX's playlist)  The director of a soft AC station in Connecticut, WEZN-FM, told Warren that he had barred the reading of top-of-hour news headlines, so that listeners wouldn't be tempted to tune away to an all-news station to learn more Soft AC stations tend to be more selective in their music libraries than other adult contemporary stations, preferring proven songs over current hits  Upon the onset of the format's popularity, core artists typically included singers such as Nat King Cole, Perry Como, Neil Diamond, Barry Manilow, Johnny Mathis, and Barbra Streisand  By the 1990s, to improve their appeal among changing demographics, some soft AC stations began to widen their playlist to include selections from contemporary acts with 80s, & 90s, musicians & bands such as Bon Jovi, Bryan Adams, Celine Dion, Roxette, Mariah Carey, Eric Clapton, Phil Collins, Elton John, Cher, Whitney Houston, Journey, and Queen  On the other hand, by 1996, New York's WLTW had begun to phase out its softer music in favor of a more uptempo direction In 2017, Inside Radio reported that soft AC had the third-largest decrease in US stations offering the format over the past decade (at 128), ranking behind only adult standards and oldies—a shift credited to aging demographics and a major boom in the wider-appealing classic hits format (which saw the largest overall increase over the same period)  Consultant Gary Berkowitz argued that the soft AC format had become increasingly irrelevant in comparison to mainstream and hot AC, due to PPM markets preferring uptempo music At the same time, however, soft AC began to experience a resurgence  In April 2016, iHeartMedia flipped its San Francisco classic soul station KISQ to soft AC as The Breeze; as of November 2018, it was the top station in the Bay Area  The trend continued into 2017 and 2018, with iHeartMedia extending its Breeze brand to other soft AC flips, and the brand (among others) being adopted by competitors such as Entercom  Industry analyst Sean Ross argued that older demographics were becoming more lucrative due to changes in listening habits among younger audiences, which prefer digital platforms such as music streaming services over linear terrestrial radio, and also noted how mainstream AC was dependent on the Top 40 charts to break new songs Current soft AC stations have continued to feature recurrents such as Michael Bolton, Celine Dion, Elton John, Fleetwood Mac, Hall & Oates, and Whitney Houston, while contemporary musicians such as Adele and Michael Bublé have also become modern fixtures of the format  In addition, the soft AC sound has diversified to include more songs that are "safe and universal" and not necessarily "soft", with Ross presenting Examples such as Simple Minds' "Don't You (Forget About Me)", as well as the retroactively-defined genre of yacht rock  Over time, some stations have gradually adjusted their playlists to include more recurrents from the 1980s and 1970s (although not to the same extent as other "soft oldies" formats, such as MeTV FM, which have also grown in popularity) 

Urban adult contemporary
The Urban adult contemporary format focuses primarily on current and classic R&B and soul music,  The format typically targets African-American adults: July 2018 numbers from Nielsen Audio recorded it as the top format among African-Americans 25–54 and 35–64  It also has a sizable popularity among younger listeners, ranking behind urban contemporary as the second-most popular format among African-American adults 18–34 in the same report, with an 18 9 audience share The format typically excludes youthful rhythmic music, such as commercial hip-hop and rap, that are usually associated with the urban contemporary format  The urban AC format is also associated with the "quiet storm"—mellower R&B ballads and slow jams, often in a jazz-influenced style  The syndicated evening program Keith Sweat Hotel focuses specifically on such music As urban contemporary stations prefer hit-driven hip-hop songs, labels typically service R&B songs to the urban AC format only  Some current R&B musicians have complained that this is an artificial divide that prevents them from reaching a wider, mainstream audience (citing the relatively smaller number of urban AC outlets in comparison to urban and rhythmic), even with attempts to give some singles a hip-hop-influenced sound to improve the potential for crossover appeal  Some acts have attempted to disassociate themselves from "R&B" to reduce the effect of this stigma, although streaming services have helped to expose R&B to a wider audience beyond urban AC radio 

Rhythmic adult contemporary
The Rhythmic adult contemporary format generally focuses on a variety of current and classic dance music, such as dance-pop, hip-hop, and R&B (often resembling a blend of the Classic hits and hot AC formats in practice)  The exact composition of current and recurrent content can vary between stations, depending on local cultures and the heritage of rhythmic formats in the market, ranging from late-80s/early-90s dance hits (including latin freestyle), to disco and Motown  Rhythmic hot AC has also been used as a format, popularized by stations such as New York's WKTU 

Smooth adult contemporary
The Smooth adult contemporary format is a variant of the smooth jazz format that incorporates mainstream and/or urban adult contemporary songs; they are designed to appeal to a wider range of demographics than a straight smooth jazz format  Some smooth AC stations may limit their airplay of jazz instrumentals to those by better-known performers such as Kenny G 

Christian adult contemporary
Contemporary Christian music (CCM) has several subgenres, one being "Christian AC"  Radio & Records, for instance, lists Christian AC among its format charts  There has been crossover to mainstream and hot AC formats by many of the core artists of the Christian AC genre, notably Amy Grant, Michael W  Smith, Kathy Troccoli, Steven Curtis Chapman, Plumb, and more recently Big Daddy Weave, Casting Crowns, For King & Country, Lauren Daigle, MercyMe, and Newsboys 

Adult album alternative
The Adult album alternative (triple-A or AAA) format generally features a diverse playlist of music that appeals to an adult audience, with a focus on emerging songs and artists, and often featuring songs that were not released as singles  The exact composition of a triple-A station's playlist can vary, with alternative rock, indie rock, and indie pop commonly used as core genres, and some stations featuring more uncommon genres such as alternative country, Americana, blues, folk music, and world music  NPR observed in 2018 that roughly half of all triple-A stations in the U S  were non-commercial stations  With the wide variety of music that is serviced to the format, adult album alternative charts have often served as a feeder for the Adult Top 40, and have been credited for breaking acts such as Dave Matthews Band and Lorde 

Christmas music
Since the 1990s it has become common for many AC stations, particularly soft AC stations, to play primarily or exclusively Christmas music during the Christmas season in November and December  While these tend mostly to be contemporary seasonal recordings by the same artists featured under the normal format, most stations will also air at least some vintage holiday tunes from older pop, MOR, and adult standards artists – such as  
Boney M , The Carpenters, Nat King Cole, Perry Como, Bing Crosby, Percy Faith, Mannheim Steamroller, Dean Martin, Johnny Mathis, Trans-Siberian Orchestra, and Andy Williams – many of whom would never be played on these stations during the rest of the year 
These Christmas music marathons typically start a few weeks before Thanksgiving Day and end after Christmas Day, or sometimes extending to New Year's Day  Afterwards, the stations usually resume their normal music fare  Several stations begin the holiday format much earlier, at the beginning of November especially after Halloween  The roots of this tradition can be traced back to the beautiful music and easy listening stations of the 1960s and 1970s 

Syndicated radio shows and networks carrying the adult contemporary format
Delilah – One of the US's most popular radio shows, Delilah airs primarily in the evening  Its Christmas Edition airs from mid-November to late December 
Intelligence for Your Life – Hosted by John Tesh, this show also airs evenings and also on weekends 
American Top 40 with Ryan Seacrest – One version of AT40 airs on US hot AC stations, which is a little different from its Top-40/CHR counterpart 
Rick Dees Weekly Top 40/Weekly Top 30 – Began offering Hot AC versions of the popular countdown show in June 1996  These shows feature the top 20 Hot AC songs in the US along with about 10 past hits from the 1980s, 1990s and early 2000s (decade)  A softer "AC" version was added in July 2009 to try to fill in the void left by Casey Kasem ending his AC countdown 
Radio Disney Music Top 30 Countdown, One version is for Hot AC stations, the other version is for Mainstream AC stations  Plays the USA Top 30 songs of the week according to Mediabase and a music rating service called ratethemusic com  This show, like Rick Dees' show, is distributed by Compass Media Networks 
Backtrax USA with Kid Kelly – Weekend programs focusing on the '80s and '90s, targeted for hot AC stations 
ABC and Dial Global both offer AC 24-hour networks programming soft and hot AC 
Tom Joyner and Steve Harvey have popular morning shows that air on urban AC (and sometimes Hip-Hop) stations  Both shows are often heard on competing stations in the same city, such as St  Louis, Philadelphia and Atlanta  Joyner's show is syndicated by ABC Radio, and Harvey's show by Premiere Radio Networks 
Retro Rewind with Dave Harris is a weekend-based radio show highlighting a massive playlist of songs from the 1980s and 1990s, interviews, spotlights and contests  The show is done live across the US on Saturday nights, taking audience requests  The show is targeted towards HOT AC and AC radio stations 
The EZ Rock network is a brand/network of soft AC heard in Canada 
Heart - A radio network in the UK that grew throughout 2009 as more stations were rebranded as "Heart" 
Smooth Radio – A UK-wide radio network that formed from six regional Smooth Radio stations 
Smoothfm – A network of two Australian commercial radio stations (based in Sydney and Melbourne) that are focused on providing an eclectic easy-listening playlist, usually featuring ballads 
Nova – A network of five Australian commercial radio station (based in Sydney, Melbourne, Brisbane, Adelaide and Perth) that are very similar to Smoothfm 
The Breeze – A group of New Zealand adult contemporary radio stations owned by MediaWorks Radio  There are 20 stations currently broadcasting throughout New Zealand 
The Bob and Sheri Show – American morning drive show based in Charlotte, North Carolina  Heard on more than 50 AC stations and the American Forces NetworkFormer syndicated programming includes Dick Clark's US Music Survey (1996–2005), Casey's Hot 20/Casey's Countdown/American Top 20/10 (1992–2009) and Top 30 USA 

See also
Adult Contemporary, a chart appearing in Billboard since 1961  This chart is typically (but not exclusively) closer to soft AC 
New-age music
Yacht rock



ground_truth: Manhattan Project