Each degree of outside average temperature below the base is one heating degree-day (HDD), and each degree above the base is one cooling degree-day (CDD). To calculate the number of heating degree-days in a month, for example, the outdoor average temperature for each day is subtracted from the base, and the results for each day are added (with negative remainders being treated as 0).

Heating degree-days are a measure of the severity and duration of cold weather; the colder the weather over a given period the higher the cumulative heating degree-day value. Similarly, the warmer the weather over a given period, the higher the cumulative cooling degree-day value. The ability to compare one week, month, or other period with another using degree-days permits the analysis of seasonal patterns of energy consumption, enables the setting and tracking fuel and power budgets, and can be used to verify that projected economies are achieved by energy-saving measures.

The growing degree-day (GDD), an extension of the degree-day concept, is defined as a day on which the mean daily temperature is one degree above the minimum temperature required for the growth of a particular crop. The GDD is used as a guide to planting times and for determining the approximate dates when a crop will be ready for harvesting.

After the American Revolution the first national Thanksgiving Day, proclaimed by President George Washington, was Nov. 26, 1789, and the Episcopal Church began celebrating an annual day of thanksgiving on the first Thursday in November. Some states established an annual Thanksgiving Day, but there was no annual national holiday until President Abraham Lincoln, urged by Sarah J. Hale, proclaimed one in 1863, appointing as the date the last Thursday of November. Although the only known contemporary account of the 1621 Plymouth harvest celebration had been rediscovered in 1841, the national Thanksgiving Day initially was not officially linked to it.

In 1939, 1940, and 1941 President Franklin D. Roosevelt proclaimed Thanksgiving the next-to-last Thursday in November. Conflicts arose between Roosevelt's proclamation and about half of those of state governors, and in 1941 Congress passed a joint resolution decreeing that Thanksgiving should fall on the fourth Thursday of November. The day is observed by church services and family reunions; the customary turkey dinner is a reminder of the wildfowl served at the Pilgrims' celebration. Canadians also celebrate a national Thanksgiving Day, on the second Monday in October; prior to 1957 it was on the last Monday of the month.

Organization and Beliefs

Mormon belief is based on the Book of Mormon, the Bible, and various revelations made to Joseph Smith. The Book of Mormon, ascribed to the prophet Mormon, recounts the early history of peoples in America from c.600 B.C. to c.A.D. 420. The Aaronic priesthood (deacons, teachers, and priests), which includes every worthy male between the ages of 12 and 19, is primarily concerned with the temporal affairs of the church; that of Melchizedek (elders and high priests) is concerned with the spiritual leadership. High priests are represented in the Council of Twelve (the Apostles) and in the first presidency (the president and two counselors—three high priests vested with supreme authority). The territorial divisions of the Mormon settlements are wards and stakes. Each ward has a bishop and two counselors; five to ten wards compose a stake.

Significant characteristics of the Mormon creed include the emphasis on revelation in the establishment of doctrines and rituals, the interdependence of temporal and spiritual life, tithing, and attention to community welfare. Mormons practice baptism for the dead; they believe that the deceased soul may receive the baptism necessary for salvation by proxy of a living believer. They also believe in "celestial marriage," whereby individuals marry for all eternity. Mormons carry out a campaign of vigorous proselytizing which has, in the course of a century and a quarter, raised the church from a handful of followers to its present size.

History

The history of the Mormons began with Smith's claim that golden tablets containing the Book of Mormon had been revealed to him, and his establishment of a headquarters for his organization at Kirtland, Ohio (1831). His following grew rapidly, particularly from the intensive missionary activity in which members engaged, both in the U.S. and abroad. Stakes of Zion, as the Mormons called their settlements, were started in W Missouri, and Smith prepared to make the region the permanent home of his people. However, the intolerance of gentile neighbors toward the Mormons's communal economy and unconventional belief system led to persecution and violence. Finally, in 1838-39, Gov. Lillburn W. Boggs ordered their expulsion (see also Doniphan, Alexander William).

The Mormons sought a new Zion in the Illinois town of Nauvoo. There, they received a charter giving them virtual autonomy, with the right to maintain their own militia, their own court, and the power to pass any laws not in conflict with the state or federal constitutions. The town expanded as converts poured in from abroad, and in 1842 it was the largest and most powerful town in Illinois. The growing wealth and strength of the Mormon community caused envy and fear among their neighbors.

At about that time, Joseph Smith, as mayor of Nauvoo, ordered the suppression of church dissidents. Violence resulted, and Smith called out the Nauvoo militia to protect the city. For this, he and his brother, Hyrum, were arrested by Illinois authorities (June 24, 1844), and charged with treason. They were jailed in Carthage, Ill., where three days later they were murdered by an angry mob.

After that many Mormons fled, dissension and suspicion were rife, and there was debate over the succession to Smith's leadership. Possible choices included another brother, William Smith, and several prominent leaders, notably Sidney Rigdon, James Jesse Strang, Lyman Wight, and Brigham Young, whom the church leaders ultimately chose.

Young proved a forceful and able leader who dominated and worked for the good of his people. Again, it became necessary for the Mormons to find a home. Under Young's guidance, a remote spot was chosen, the valley of the Great Salt Lake in what is now Utah. Those who rejected Young's leadership and claimed the succession for a son of Joseph Smith declined to accompany the main body to Utah; they ultimately constituted themselves into a separate church (see Community of Christ).

In July, 1847, the first settlers reached what is now Salt Lake City and began an agricultural community. The first few years were extremely difficult, but the organization of the Mormons for community welfare, their great industry, and the determined leadership of Young made for their success. Through extensive irrigation, farming prospered.

In 1849, the Mormons wished to have their communities admitted to the Union as the State of Deseret, but the area became Utah Territory instead. Brigham Young was appointed territorial governor and superintendent of Indian affairs, but Mormon isolation was destroyed. Non-Mormons filtered in, resented by the Mormons. Young's formal announcement in 1852 of the doctrine of plural marriage, based on a vision of Joseph Smith in 1843, set the Mormons further apart from their fellow Americans. Thereafter, polygamy was luridly discussed in newspapers across the country. The antagonism was very strong in the 1850s, and when Col. Albert S. Johnston was sent out with an army force in 1857, Young prepared to defend the Mormon state. The Utah War did not rise to serious proportions, but the bitterness of feeling was shown after the massacre of the members of a wagon train at Mountain Meadows in 1857, for which the Mormons were blamed.

The question of plural marriage was the important point in Utah's bid for statehood. Congress passed laws against polygamy aimed solely at Utah. Despite persecution, the Mormon community was a thoroughly established commonwealth by the time of Brigham Young's death in 1877. Statehood was finally granted after Mormon president Wilford Woodruff made a statement (1890) withdrawing church sanction of polygamy: Utah entered the Union as the 45th state in 1896. Since then, the church has spread beyond Utah, becoming truly international in the late 20th cent. when church membership roughly doubled. More than half of all Mormons now live outside the United States.

A number of Mormons, generally referred to as fundamentalists, continue to believe in plural marriage, either as members of a splinter church or quietly within the mainstream church, which excommunicates those who adhere to the practice. Some 10,000 people in North America belong to the Fundamentalist Church of Jesus Christ of Latter Day Saints, the largest of the splinter faiths. Many of its members live in SW Utah and NW Arizona.

Any plant of the genus Hemerocallis, in the lily family, consisting of about 15 species of perennial herbaceous plants distributed from central Europe to eastern Asia. Members have long-stalked clusters of funnel- or bell-shaped flowers that range in colour from yellow to red and are each short-lived (hence “day” lily). Daylilies have fleshy roots and narrow, sword-shaped leaves that are grouped at the base of the plant. The fruit is a capsule. Some species are cultivated as ornamentals or for their edible flowers and buds.

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Time required for a celestial body to turn once on its axis; especially, the period of the Earth's rotation. The sidereal day (see sidereal period) is the time required for the Earth to rotate once relative to the background of the stars (i.e., the time between two observed passages of a star over the same meridian of longitude). The apparent solar day is the time between two successive transits of the Sun over the same meridian. Because the orbital motion of the Earth makes the Sun seem to move slightly eastward each day relative to the stars, the solar day is about four minutes longer than the sidereal day. The mean solar day is the average value of the solar day, which changes slightly in length during the year as the Earth's speed in its orbit varies.

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Lovers' holiday celebrated on February 14, the feast day of St. Valentine, one of two 3rd-century Roman martyrs of the same name. St. Valentine is considered the patron of lovers and especially of those unhappily in love. The feast day became a lovers' festival in the 14th century, probably as an extension of pagan love festivals and fertility rites celebrated in mid-February. Today it is marked by the exchange of romantic cards (valentines), flowers, and other gifts.

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U.S. holiday. It originated in the autumn of 1621 when Plymouth governor William Bradford invited neighbouring Indians to join the Pilgrims for a three-day festival of recreation and feasting in gratitude for the bounty of the season, which had been partly enabled by the Indians' advice. Neither the standard Thanksgiving meal of turkey, cranberry sauce, and pumpkin pie nor the family orientation of the day reflects the Plymouth event, however. Proclaimed a national holiday in 1863, Thanksgiving is celebrated on the fourth Thursday in November (though it was moved back one week in 1939–41 to extend the Christmas shopping season). Canada adopted Thanksgiving as a national holiday in 1879; since 1957 it has been celebrated on the second Monday in October.

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(born March 26, 1930, El Paso, Texas, U.S.) U.S. jurist. After graduating first in her law school class at Stanford University (1950), she entered private practice in Arizona. She served as an assistant state attorney general (1965–69) before being elected in 1969 to the state senate, where she became the first woman in the U.S. to hold the position of majority leader (1972–74). After serving on the superior court of Maricopa county and the state court of appeals, she was nominated in 1981 by Pres. Ronald Reagan to the Supreme Court of the United States, becoming the first female justice in the court's history. Known for her dispassionate and meticulously researched opinions, she proved to be a moderate and pragmatic conservative who sometimes sided with the court's liberal minority on social issues (e.g., abortion rights). O'Connor retired from the court in 2006.

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First day of the new year, celebrated with religious, cultural, and social observances around the world. It is usually marked by rites and ceremonies that symbolize casting off the old year and rejoicing in the new. Most of the world recognizes January 1 as the start of a new year because the Gregorian calendar, from its papal origin in 1582, has become the international reference for treaties, corporate contracts, and other legal documents. Nevertheless, numerous religious and national calendars have been retained. For example, in the Persian calendar (used in Iran and Afghanistan) New Year's Day falls on the spring equinox (March 20 or 21 in the Gregorian calendar). The more widely employed Islamic (Hijrī) calendar is based on 12 lunar months of 29 or 30 days; thus, the Islamic New Year's Day gradually regresses through the longer Gregorian calendar. The Hindu new year starts on the day following the first new moon on or after the spring equinox. The Chinese new year begins at sunset on the new moon in the sign of Aquarius (late January or early February). The Hebrew calendar is based on 12 lunar months (13 in certain years) of 29 or 30 days; the Jewish New Year's Day, or Rosh Hashanah, can fall anytime from September 6 to October 5 in the Gregorian calendar.

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U.S. holiday. Originally held (1868) in commemoration of soldiers killed in the American Civil War, its observance later extended to all U.S. war dead. Most states conform to the federal practice of observing it on the last Monday in May, but some retain the traditional day of celebration, May 30. National observance is marked by the placing of a wreath on the Tomb of the Unknowns in Arlington National Cemetery. Flags, insignia, and flowers are placed on the graves of veterans in local cemeteries.

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In Europe, the day (May 1) for traditional springtime celebrations. It probably originated in pre-Christian agricultural rituals. Celebrations included a May king and queen, a Maypole, and people carrying trees, green branches, or garlands. May Day was designated an international labour day by the International Socialist Congress of 1899, and it remains the standard Labour Day worldwide, with a few exceptions, including Canada and the U.S. A major holiday in the Soviet Union and other communist countries, it was the occasion for important political demonstrations.

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Member of the Church of Jesus Christ of Latter-day Saints or of a sect closely related to it (e.g., the Community of Christ). The Mormon religion was founded by Joseph Smith, who claimed to have received an angelic vision telling him of the location of golden plates containing God's revelation; this he published in 1830 as the Book of Mormon. Smith and his followers accepted the Bible as well as the Mormon sacred scriptures but diverged significantly from orthodox Christianity, especially in their assertion that God exists in three distinct entities as Father, Son, and Holy Spirit. Mormons also believe that faithful members of the church will inherit eternal life as gods. Other unique doctrines include the belief in preexisting souls waiting to be born and in salvation of the dead through retroactive baptism. The church became notorious for its practice of polygamy, though it was officially sanctioned only between 1852 and 1890. Smith and his followers migrated from Palmyra, N.Y., to Ohio, Missouri, and finally Illinois, where Smith was killed by a mob in 1844. In 1846–47, under Brigham Young, the Mormons made a 1,100-mi (1,800-km) trek to Utah, where they founded Salt Lake City. In the early 21st century, the church had a worldwide membership of nearly 10 million, swelled yearly by the missionary work that church members, both men and women, are encouraged to perform.

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Annual holiday devoted to the recognition of working people's contribution to society. It is observed on the first Monday in September in the U.S. and Canada. It was first celebrated in New York City on Sept. 5, 1882, under the sponsorship of the Knights of Labor. Various U.S. states observed the holiday before 1894, when Congress passed a bill making Labor Day a national holiday. It is often celebrated with parades and speeches, as well as political rallies, and the day is sometimes the official kickoff date for national political campaigns in the U.S. In most other countries, workers are honoured on May Day.

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Anniversary of the adoption of the U.S. Declaration of Independence by the Second Continental Congress (July 4, 1776). It is the greatest secular holiday in the country. Celebrating the day became common only after the War of 1812. Thereafter, civic-minded groups worked to link the ideals of democracy and citizenship to the patriotic spirit of the day.

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Annual Canadian holiday. Observed on July 1, it commemorates the formation of the Dominion of Canada on July 1, 1867. With the 1982 passage of the Canada Act, its name was officially changed to Canada Day. It is celebrated with parades, fireworks, flag display, and the singing of the national anthem, “O Canada.”

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(born April 27, 1904, Ballintubbert, County Leix, Ire.—died May 22, 1972, Hadley Wood, Hertfordshire, Eng.) Irish-born British poet. Son of a clergyman, Day-Lewis studied at the University of Oxford and in the 1930s became part of a circle of left-wing poets centred on W.H. Auden, though he later turned to an individual lyricism expressed in traditional forms. His works include translations of Virgil's Georgics (1940), Aeneid (1952), and Eclogues (1963) and the verse collections The Room (1965) and The Whispering Roots (1970). He also wrote the autobiography The Buried Day (1960) and several detective novels under the pseudonym Nicholas Blake. He became poet laureate of England in 1968. He was the father of actor Daniel Day-Lewis.

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Jewish religious holiday, observed on the 10th day of the lunar month of Tishri (in late September or early October). It concludes the 10 days of repentance that begin with Rosh Hashanah. Its purpose is to purify the individual and community by forgiving the sins of others and by repenting one's own sins against God. Before the destruction of the Temple of Jerusalem, the high priest performed a sacrificial ceremony that concluded with the death of a scapegoat. Today it is marked by fasting and abstention from sex. Its eve, when the Kol Nidre is recited, and the entire day of Yom Kippur, are spent in prayer and meditation.

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In the Roman Catholic church, a day commemorating all the Christians believed to be in purgatory. Celebrated on November 2, it was first established by Odilo (d. 1049), abbot of Cluny, in the 11th century, and it was widely celebrated by the 13th century. The date follows All Saints' Day, with the idea that remembering the saints in heaven should be followed by remembering the souls awaiting release from purgatory. Roman Catholic doctrine holds that the prayers of the faithful on earth will help cleanse these souls in order to prepare them for heaven.

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In Christianity, a day commemorating all the saints of the church, known and unknown. It is celebrated on November 1 in the Western churches and on the first Sunday after Pentecost in the Eastern churches. The first general observance of All Saints' Day was ordered by Pope Gregory IV in 837. In medieval England the festival was called All Hallows, and its eve is still known as Halloween.

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