Britannica Concise 2005

espalier \is-'pal-y9r\ Tree or other plant trained to grow flat against a support (such as a trellis or wall). The term is also used for the support

© 2006 Encyclopaedia Britannica, Inc.

Espanol ► Essex Junto I 635

itself, as well as for the method or technique. The technique was devel¬ oped in Europe to encourage fruit-tree production in an incompatible cli¬ mate; it originally used a wall to provide heat as well as support. Decorative or space-saving espaliers use metal, wire, or wooden frames to create ornamental shapes for shrubbery or to train trees on trellises, walls, or fences. Evergreens such as loquat, fire thorn, sweet bay mag¬ nolia, and upright yew, as well as dwarf apple and pear trees, make excel¬ lent espaliers.

Espanol, Pedro See Pedro Berruguete

Espartero \,a-spar-'ta-ro\, Baldomero, prince de Vergara (b.

Oct. 27, 1793, Granatula, Spain—d. Jan. 8, 1879, Logrono) Spanish gen¬ eral and politician. After the accession of Isabella II, he joined the govern¬ ment forces opposed to Don Carlos (see Carlism) and helped win the First Carlist War. He became head of the government in 1840 and was appointed regent in 1841. In 1843 a generals’ revolt forced him to flee to England, where he lived until 1849. He returned to Spain, then shared control of the government (1854-56) with Gen. Leopoldo O’Donnell (1809-67) before returning to retirement.

esparto \is-'par-to\ Either of two species of gray-green needlegrasses (Stipa tenacissima and Lygeum spartum), native to southern Spain and northern Africa, or the fibre produced by esparto. L. spartum grows in rocky soil on the high plains. S. tenacissima flourishes in sandy, iron-rich soils in dry, sunny locations on the seacoast. Esparto fibre has great strength and flexibility; it is used for making ropes, sandals, baskets, mats, and other durable articles. Esparto leaves are used in the manufacture of paper.

Esperanto ^es-po-'ran-toN Artificial language created in 1887 by Laz¬ arus Ludwig Zamenhof (1859-1917), a Polish oculist, for use as an inter¬ national second language. Zamenhof’s Fundamento de Esperanto (1905) outlines its basic principles. All words, derived from roots commonly found in the European languages, are spelled as pronounced, and gram¬ mar is simple and regular. Nouns have no gender and end in -o, and there is only one definite article, la (e.g., la amiko, “the friend”). Adjectives are marked by the ending -a. Verbs are regular and have only one form for each tense or mood. The Universal Esperanto Association (founded 1908) has members in 83 countries. Estimates of the number of Esperanto- speakers range from 100,000 to several million.

espionage Ves-pe-3-,nazh\ Practice of obtaining military, political, commercial, or other secret information by means of spies or illegal moni¬ toring devices. It is sometimes distinguished from the broader category of intelligence gathering by its aggressive nature and its illegality. Coun¬ terespionage efforts are directed at detecting and thwarting espionage by others.

Espiritu Santo formerly Marina Island, northwestern Vanuatu, South Pacific Ocean. Vanuatu’s largest island, Espfritu Santo is 76 mi (122 km) long and 45 mi (72 km) wide and covers 1,420 sq mi (3,677 sq km). Vol¬ canic in origin, it has a mountain range running along its western coast; Mount Tabwemasana rises to 6,165 ft (1,879 m). It is heavily wooded and has broad, fertile, well-watered valleys. Agriculturally developed, its prin¬ cipal settlement is Luganville (Santo) on the southeastern coast.

Esquire U.S. monthly magazine, founded in 1933 by Arnold Gingrich. It began as an oversized magazine for men that featured a sophisticated style and drawings of scantily clad young women. It later abandoned the risque drawings but continued to cultivate the image of affluence and refined taste. It pioneered the treatment of unconventional topics and fea¬ ture stories and attracted a general-interest audience with pieces by well- known writers. In the 1940s, because of its early notoriety, it was the object of an ultimately unsuccessful court case challenging its worthiness for mailing privileges at desirable rates. By the late 20th century, Esquire had lost its literary distinctiveness.

essay Analytic, interpretative, or critical literary composition, usually dealing with its subject from a limited and often personal point of view. Flexible and versatile, the essay was perfected by Michel de Montaigne, who chose the name essai to emphasize that his compositions were “attempts” to express his thoughts and experiences. The essay has been the vehicle of literary and social criticism for some, while for others it could serve semipolitical, nationalistic, or polemical purposes and could have a detached, playful, earnest, or bitter tone.

Essen City (pop., 2002 est.: city, 591,889; metro, area, 5,823,685), North Rhine-Westphalia state, western Germany. Located on the Ruhr River, it is the site of an extensive ironworks and steelworks. It was originally the seat of a convent (founded 852), whose 15th-century cathedral still stands. Essen became a city in the 10th century and was locally sovereign until 1802, when it passed to Prussia. The development of ironworks, steel¬ works, and coal mines stimulated growth in the 19th century. The city was largely destroyed in World War II, when it was targeted by the Allies as a centre of the German war industry. It has since been rebuilt with large, modern buildings, including concert halls, an economic research institute, and an art institute.

Essene \i-'sen, 'e-sen \ Member of a Jewish sect active in Palestine from the 2nd century bc to the 1st century ad. The Essenes formed small monas¬ tic communities whose members strictly observed the laws of Moses and the Sabbath and held their property in common. They withdrew from society, avoiding temple worship in Jerusalem and supporting themselves by manual labor. They usually excluded women. It is likely that the Dead Sea Scrolls were composed, copied, or collected by the Essenes.

essential oil Any of a class of highly volatile (readily evaporating) organic compounds found in plants and usually named for them (e.g., rose oil, peppermint oil). They have been known and traded since ancient times. Many essential oils contain isoprenoids. Some, such as oil of win- tergreen (methyl salicylate) and orange oil (d-limonene), have one pre¬ dominant component, but most have dozens or hundreds. Trace components impart an oil’s characteristic odour, which synthetic or blended oils can rarely duplicate. Essential oils have three primary com¬ mercial uses: as odorants in perfumes, soaps, detergents, and other prod¬ ucts; as flavours in baked goods, candies, soft drinks, and many other foods; and as pharmaceuticals, in dental products and many medicines (see aromatherapy).

essentialism In ontology, the view that some properties of objects are essential to them. The “essence” of a thing is conceived as the totality of its essential properties. Theories of essentialism differ with respect to their conception of what it means to say that a property is essential to an object. The concept of an essential property is closely related to the concept of necessity, since one way of saying that a property P is essential to an object O is to say that the proposition “O has P” is necessarily true (see neces¬ sity). A general but not very informative way of characterizing essential properties is to say that a property is essential to an object if the object cannot lack the property and still be the object that it is. Properties of an object that are not essential in this sense are said to be accidental. See also IDENTITY OF INDISCERNABLES.

Essequibo \,e-se-'kwe-bo\ River River, east-central Guyana. The larg¬ est river between the Amazon and the Orinoco rivers and the longest in Guyana, it rises in the Acarai Mountains on the Brazilian border. It flows north for about 630 mi (1,000 km) to empty into the Atlantic Ocean 13 mi (21 km) from Georgetown. Its estuary, 20 mi (32 km) wide, is obstructed by islands and silt but is navigable by small ocean vessels to Bartica, 50 mi (80 km) inland.

Essex Administrative (pop., 2001: 1,310,922), geographic, and historic county, eastern England. It extends along the North Sea coastline between the estuaries of the Rivers Thames and Stour. Chelmsford, centrally situ¬ ated, has long been the county headquarters and is also the seat of a church diocese. The ancient county stretched west as far as Middlesex, but Greater London now incorporates its southwestern comer. It was a Roman centre until the 5th-century Saxon invasions; it became one of the Anglo-Saxon kingdoms of the Heptarchy and had its centre at London. It came under Danish control in the 9th century and was later reconquered by Wessex. Despite its proximity to London, much of Essex remains rural, and the county is highly farmed; it is also the site of petroleum installations on the River Thames and of a nuclear power plant. The University of Essex is at Colchester.

Essex Junto Vjon-.toX Informal group of Federalist Party political lead¬ ers in Massachusetts, mainly from Essex county. Its members supported Alexander Hamilton and friendship with Britain and opposed Thomas Jef¬ ferson, the Embargo Act, and the War of 1812. Its leaders, including Timothy Pickering, tried to form a separate confederation in New England and participated in the Hartford Convention. They declined in importance after 1814.

© 2006 Encyclopaedia Britannica, Inc.

636 i Essex ► Estienne

Essex, Robert Devereux, 2nd earl of (b. Nov. 10, 1567, Neth- erwood, Herefordshire, Eng.—d.

Feb. 25, 1601, London) English sol¬ dier and courtier. He was the son of the 1st earl of Essex. As a young man, he became the aging Elizabeth I’s favorite, though their relationship was stormy. In 1591-92 he com¬ manded the English force in France that helped Henry IV fight the French Roman Catholics, and in 1596 he commanded forces in the sack of Cadiz. In 1599 Elizabeth sent him to Ireland as lord lieutenant, where he fought an unsuccessful campaign against Irish rebels and concluded an unfavorable truce, leading Elizabeth to deprive him of his offices in 1600.

In 1601 he made an unsuccessful attempt to raise the populace of Lon¬ don in revolt against Elizabeth; he was captured, tried by his former mentor Francis Bacon, and beheaded.

Essex, Robert Devereux, 3rd earl of (b. 1591, London, Eng.—d.

Sept. 14, 1646, London) English military commander. Son of the 2nd earl of Essex, he began his military career in 1620 and commanded forces for Charles I until the Long Parlia¬ ment deposed Charles’s ministers (1640). As the English Civil Wars began, he was appointed to command the Parliamentary army. He fought against the Royalists at the indecisive Battle of Edgehill (1642) and advanced on London in 1643. His army was besieged at Lostwithiel, Cornwall, in 1644, and all surrendered except Essex, who escaped by sea. He resigned his command in 1645.

Essex, Walter Devereux, 1st earl of (b. Sept. 16, 1541, Car¬ marthen, Carmarthenshire, Wales—d. Sept. 22, 1576, Dublin, Ire.) English soldier. Born to a titled family, he helped suppress a rebellion in northern England in 1569 and was made earl of Essex in 1572. In 1573 he offered to subdue and colonize, at his own expense, a portion of Ulster that had not accepted English overlordship. There he treacherously cap¬ tured and executed the Irish rebel leaders and massacred hundreds of the populace, contributing to Irish bitterness toward the English. Elizabeth I commanded him to break off the enterprise in 1575. He died of dysen¬ tery shortly after returning to Ireland from England.

establishment clause or establishment-of-religion clause

Clause in the 1st Amendment to the U.S. Constitution forbidding Con¬ gress from establishing a state religion. It prevents the passage of any law that gives preference to or forces belief in any one religion. It is paired with a clause that prohibits limiting the free expression of religion.

estate law Laws governing the nature and extent of an owner’s rights with respect to real and personal property. When used in connection with probate proceedings, it refers to the laws governing the disposition of the total property of whatever kind owned by a person at the time of death. See also estate tax, property, property tax.

estate tax Levy on the value of property changing hands at the death of the owner, fixed mainly by reference to its total value. Estate tax is generally applied only to estates whose value exceeds a set amount, and it is applied at graduated rates. An estate tax was first instituted in the U.S. in 1898 to help finance the Spanish-American War; it was repealed in 1902 but permanently reimposed in 1916, initially to help finance mobi¬ lization for World War I. Methods of avoiding estate tax (e.g., gifts and trust funds) were largely foiled by the U.S. Tax Reform Act of 1976.

Estates General or States General French Etats-Generaux.

In pre-Revolutionary France, the representative assembly of the three “estates” or orders of the realm: the clergy and the nobility (both privi¬ leged minorities) as well as the Third Estate, which represented the major¬ ity of the people. Usually summoned by monarchs in times of crisis, the Estates General met at irregular intervals from the 14th century on; it was of limited effectiveness because the monarchy usually dealt with local Estates instead. The last meeting of the Estates General was at the start

of the French Revolution in 1789, when the deputies of the Third Estate led in founding the National Assembly.

Este family \'es-ta\ Princely family of Lombard origin prominent in the history of medieval and Renaissance Italy. The Estensi, a branch of the 10th-century dynasty of the Obertenghi, took their name from the town¬ ship and castle of Este, near Padua. The founder of the family was the margrave Alberto Azzo II (died 1097), through whose son Folco I (died 1136?) descended the House of Este. The family first gained prominence as leaders of the Guelphs in the wars between the Guelphs and Ghibelunes. Members of the family ruled in Ferrara in the 13th-16th century. After Alfonso II (1533-1597), the fifth and last duke of Ferrara, died childless, direct papal rule was established in Ferrara in 1598, and the main branch of the Este family came to an end. The family also ruled in Modena and Reggio from the late Middle Ages to the late 18th century. In addition to their political prominence, members of the family also played an impor¬ tant role as promoters of art and culture.

Estenssoro, Victor Paz See Victor Paz Estenssoro

ester Any of a class of organic compounds that can react with water (see hydrolysis) to produce an alcohol and an organic or inorganic acid. They are formed by the reverse process, esterification, in which acid reacts with alcohol to form an ester and water. Esters of carboxylic acids, the most common esters, contain the acid’s carbonyl group (—C=0; see func¬ tional group); the carbon’s fourth bond is with the alcohol’s oxygen atom. Hydrolysis of esters in the presence of an alkali (saponification) is used to make soaps from fats and oils. Carboxylic acid esters of low molecu¬ lar weight are colourless, volatile liquids with pleasant odours; they give flavour and fragrance to fruits and flowers and are used as synthetic fla¬ vours and fragrances. Others, such as ethyl acetate and butyl acetate, are used as solvents for lacquers, paints, and varnishes. Certain polymers are esters, including Lucite (polymethyl methacrylate) and Dacron (polyeth¬ ylene terephthalate). Esters of alcohols and inorganic acids include nitrate esters (e.g., nitroglycerin), which are explosive; phosphate esters, includ¬ ing such biologically important compounds as nucleic acids; and others that are used as flame retardants, solvents, plasticizers, gasoline and oil additives, and insecticides.

Esterhazy family Ves-t9r-,ha-ze\ Aristocratic Magyar family, dating from at least the 15th century, that produced numerous Hungarian diplo¬ mats, army officers, and patrons of the arts. By the 18th century the Ester- hazys were the largest landowners in Hungary and possessed a private fortune even larger than that of the Habsburg emperors, whom they sup¬ ported. The great Esterhazy palace was built at Eisenstadt, on Neusiedler Lake. FJ. Haydn spent most of his career as music director at the palace. The family’s various members held important governmental, ecclesiasti¬ cal, diplomatic, and military posts in Hungary well into the 20th century.

Estes \'es-tez\, William K(aye) (b. June 17, 1919, Minneapolis, Minn., U.S.) U.S. psychologist. He worked with B.F. Skinner on instru¬ mental learning in the 1940s, and in 1950 he introduced stimulus sam¬ pling theory (SST), a model for describing learning mathematically. He taught at Stanford, Rockefeller, and Harvard universities, among others. Estes’s later work focused on “cognitive architectures.” His works include Learning Theory and Mental Development (1970), Statistical Models in Behavioral Research (1991), and Classification and Cognition (1994). In 1997 he received the National Medal of Science.

Esther Heroine and central figure in the book of Esther. She was a beau¬ tiful Jewish woman, the wife of the Persian king Ahasuerus (Xerxes I). She and her cousin Mordecai persuaded the king to cancel an order for the extermination of Jews in his realm, plotted by the king’s chief minister, Haman. Instead, Haman was hanged on the gallows he had built for Mor¬ decai, and the Jews were given permission to destroy their enemies. The Jewish festival of Purim celebrates this event. The book of Esther was probably written in the 2nd century bc.

Estienne \a-'tyen\, Henri II or Henri II Etienne (b. 1528, Paris, France—d. 1598, Lyon) French scholar-printer. As a young man he trav¬ eled Europe studying ancient manuscripts and visiting scholars before returning to his father’s Geneva printing firm to publish the first printed editions of several Greek texts. In 1566 he published a Latin edition of Herodotus with a controversial apologia in which he bitterly satirized his own age. His voluminous output of classical scholarship also included a 13-volume Greek and Latin text of Plutarch and a 5-volume Greek dic-

Robert Devereux, 2nd earl of Essex, detail of a painting after Marcus Gheeraerts the Younger, late 16th cen¬ tury; in the National Portrait Gallery, London

COURTESY OF THE NATIONAL PORTRAIT GALLERY, LONDON

© 2006 Encyclopaedia Britannica, Inc.

estimation > Ethelred II I 637

tionary. Thesaurus graecae linguae (both 1572). New editions of the dic¬ tionary, his greatest work, were printed into the 19th century.

estimation In mathematics, use of a function or formula to derive a solution or make a prediction. Unlike approximation, it has precise con¬ notations. In statistics, for example, it connotes the careful selection and testing of a function called an estimator. In calculus, it usually refers to an initial guess for a solution to an equation, which is gradually refined by a process that generates closer estimates. The difference between the estimate and the exact value is the error.

Estonia officially Republic of Estonia Country, northeastern Europe. It consists of a mainland area and some 1,500 islands and islets in the Baltic Sea. Area: 17,462 sq mi (45,227 sq km). Population (2005 est.):

1,345,000. Capital: Tallinn. Estonians make up about two-thirds of the popula- l '' 3 ' o *' eo km' h° n - R uss i ans account for almost one-

--— third, and there are Ukrainian, Finnish,

and Belarusian minorities. Language: Estonian (official). Religion: Christianity (other Christians [mostly unaf¬ filiated], Protestant, Eastern Orthodox). Currency: kroon. The land is low and hilly, with numerous lakes, forests, and rivers. It has a cool-temperate and humid climate. The economy is mainly industrial, producing shale oil, machinery, fabricated metal products, and building materials. It is noted for its textiles, and woodworking is a traditional and important industry. Estonia is a republic with one legislative body; the chief of state is the president, and the head of government is the prime minister. It was invaded by Vikings in the 9th century ad and later by Danes, Swedes, and Russians, but the Estonians were able to withstand the assaults until the Danes took control in 1219. In 1346 the Danes sold their sovereignty over Estonia to the Teutonic Order, which was then in possession of Livonia (southern Estonia and Latvia). In the mid-16th century Estonia was once again divided: northern Estonia capitulated to Sweden, and Poland gained Livonia, which it surrendered to Sweden in 1629. Russia acquired Livo¬ nia and Estonia in 1721. Nearly a century later, serfdom was abolished. From 1881 Estonia underwent intensive Russification. In 1918 Estonia obtained independence from Russia, which lasted until the Soviet Union occupied the country in 1940 and forcibly incorporated it into the U.S.S.R. Germany held the region (1941-44) during World War II, but the Soviet regime was restored in 1944, after which Estonia’s economy was collec¬ tivized and integrated into that of the Soviet Union. In 1991, along with other parts of the former U.S.S.R., Estonia proclaimed its independence and subsequently held elections. In the 21st century Estonia continued negotiations with Russia to settle their common border, and, along with the other Baltic states, it joined the European Union in 2004.

Estremadura See Extremadura

estrogen Ves-trs-jofo Any of a class of hormones that primarily influ¬ ence the female reproductive system’s development, maturation, and func¬ tion. The three major estrogens—estradiol, estrone, and estriol—are produced mainly by the ovaries and placenta; the adrenal glands and the testes secrete smaller amounts. Estrogens affect the ovaries, vagina, fal¬ lopian tubes, uterus, and mammary glands and play crucial roles in puberty, menstruation, pregnancy, and parturition (labour). They also influence the structural differences between female and male bodies. In experimental animals, loss of estrogens diminishes mating desires and other behavioral patterns.

estrus Period in the sexual cycle of female mammals, except the higher primates, during which they are in heat (ready to accept a male for mat¬ ing). Some animals (e.g., dogs) have only one heat during a breeding sea¬ son; others (e.g., ground squirrels) will come into heat repeatedly during the breeding season until impregnated. During estrus the female secretes pheromones that signal her receptivity to the males; her genital area may become swollen, and she may also give behavioral signals.

estuary Ves-cho-.wer-eX Partly enclosed coastal body of water in which river water is mixed with seawater. An estuary is thus defined by salinity rather than geography. Many coastal features designated by other names are in fact estuaries (e.g., Chesapeake Bay). Some of the oldest continu¬ ous civilizations have flourished in estuarine environments (e.g., the land between the Tigris and Euphrates rivers, the Nile delta, the Ganges delta, and the lower Huang He valley). Cities such as London (River Thames), New York (Hudson River), and Montreal (St. Lawrence River) developed on estuaries and became important commercial centres.

Etana Epic \a-'ta-na\ Ancient Mesopotamian myth concerning dynastic succession. The gods chose Etana as the first king, but his wife, though pregnant, could not give birth, and thus Etana had no heir. The god Sha- mash answered Etana’s prayers by directing him to rescue a maimed eagle, which rewarded Etana by carrying him high up in the sky, near heaven, where Etana could obtain the birth plant to help his wife. Surviving texts are incomplete and divergent: in one version Etana makes it to heaven (but the text then breaks off); in another he falls to earth. A king named Etana ruled Kish in southern Mesopotamia sometime in the 3rd millen¬ nium BC.

etching Method of engraving in which lines or textures are bitten, or etched, into a metal plate, usually copper, with acid. The image produced has a spontaneity of line that comes from drawing on the plate in the same direct way as with pen or pencil on paper. The first etchings date from the early 16th century, but the basic principle had been used earlier for the decoration of armour. Among the pioneers of the medium were Al¬ brecht Altdorfer, Albrecht DOrer, and Parmigianino; the greatest of all etch¬ ers was Rembrandt. In the 20th century, etching was especially popular for book illustration. See also aquatint; engraving.

ethanol \'e-th3-,n6l\ or ethyl alcohol or grain alcohol Organic compound, most important of the alcohols, chemical formula CH 3 CH 2 OH. Produced by fermentation, it is the intoxicating ingredient in alcoholic beverages. Ethanol for industrial purposes is made by either fer¬ mentation or chemical synthesis, then purified by distillation and, to avoid the tax levied on ethyl alcohol for drinking, made unfit to drink (see dena- turation) by mixing it with compounds such as methanol, benzene, or kero¬ sene. Ethanol has many uses as a solvent, a raw material, an extraction medium, an antifreeze, an antiseptic, and a gasoline additive and substi¬ tute. It is toxic, depressing the central nervous system, and addictive to some persons (see alcoholism). Moderate amounts depress the inhibitory activities of the brain and so appear to stimulate the mind, but larger amounts seriously impair coordination and judgment; excessive consump¬ tion can cause coma and death. Taking ethanol in combination with bar¬ biturates or related drugs is especially dangerous.

Ethelbert I or Aethelberht I (d. Feb. 24, 616) King of Kent (560- 616). He married the Christian Bertha, daughter of the king of Paris, and, when St. Augustine of Canterbury and other missionaries arrived in Kent in 597, he welcomed them and gave them a dwelling at Canterbury. Though baptized by Augustine along with thousands of his subjects, he did not try to establish Christianity by decree. He produced the first writ¬ ten laws in Anglo-Saxon (see Anglo-Saxon law).

Ethelred II or Aethelred Unraed known as Ethelred the Unready (b. 968?—d. April 23, 1016, London) King of the English

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© 2006 Encyclopaedia Britannica, Inc.

638 i ether ► Ethiopian Orthodox church

(978-1013, 1014-16). He became king after his half brother’s assassina¬ tion and was suspected of involvement in the murder. An ineffectual ruler, he failed to mount an organized defense against the Danish invasions (from 980); his massacre of Danish settlers (1002) provoked further attacks. When Sweyn I was accepted as king in England in 1013, Ethel- red fled to Normandy. He returned to the throne on the death of Sweyn in 1014, but on his death he was succeeded by the Dane Canute the Great. His epithet “Unraed” means “evil counsel” and has been translated incor¬ rectly as “the Unready.”

ether \'e-thor\ Any of a class of organic compounds whose molecular structure has an oxygen atom interposed between two carbon atoms that are part of hydrocarbon molecules. Ethers have the general chemical for¬ mula ROR', in which R and R' represent the hydrocarbons. They resemble alcohols but generally are less dense, less soluble in water, more volatile, and more inert. They are used in chemical processing, for extraction and separation of chemicals, and as solvents. Some are used as insecticides and soil fumigants. They are also used in medicine and pharmacology. Codeine is the methyl ether of morphine. The term ether often refers to ethyl ether (C 2 H 5 OC 2 H 5 ), best known as an anesthetic but also used as a solvent, an extractant, and a reaction medium.

Etherege \'eth-rij\, Sir George (b. c. 1635, Maidenhead, Berkshire, Eng.?—d. c. May 10, 1692) British playwright. He is remembered as the creator of the Restoration comedy of manners. His first comedy. Love in a Tub (1664), was an immediate success and was novel in its lively exploitation of contemporary manners. He also wrote She Wou’d if She Cou’d (1668) and the popular The Man of Mode (1676). Though his own plays ceased to be performed after the 18th century, his style of comedy was adopted by later playwrights and persisted into modern times.

Ethernet Telecommunications networking protocol introduced by Xerox Corp. in 1979. It was developed as an inexpensive way of sending information quickly between office machines connected together in a single room or building, but it rapidly became a standard computer inter¬ connection method. The original data rate of 10 megabits per second has been increased to 100 megabits per second for a new standard known as fast ethemet. The original specification required coaxial cable as the com¬ munications medium, but costs have been reduced through the employ¬ ment of simple paired wires. See also computer network.

ethical relativism Philosophical view that what is right or wrong and good or bad is not absolute but variable and relative, depending on the per¬ son, circumstances, or social situation. Rather than claiming that an action’s rightness or wrongness can depend on the circumstances, or that people’s beliefs about right and wrong are relative to their social condi¬ tioning, it claims (in one common form) that what is truly right depends solely on what the individual or the society thinks is right. Because what people think will vary with time and place, what is right will also vary. If, however, changing and even conflicting moral principles are equally valid, there is apparently no objective way of justifying any principle as valid for all people and all societies. This conclusion is rejected by consequentialists (see consequentiausm) and deontologists (see deontological ethics) alike.

ethics Branch of philosophy concerned with the nature of ultimate value and the standards by which human actions can be judged right or wrong. The term is also applied to any system or theory of moral values or prin¬ ciples. Ethics is traditionally subdivided into normative ethics, metaeth¬ ics, and applied ethics. Normative ethics seeks to establish norms or standards of conduct; a crucial question in this field is whether actions are to be judged right or wrong based on their consequences or based on their conformity to some moral rule, such as “Do not tell a lie.” Theories that adopt the former basis of judgment are called consequentialist (see con- sequentialism); those that adopt the latter are known as deontological (see deontological ethics). Metaethics is concerned with the nature of ethical judgments and theories. Since the beginning of the 20th century, much work in metaethics has focused on the logical and semantic aspects of moral language. Some major metaethical theories are naturalism (see NATURAUSTIC FALLACY), INTUITIONISM, EMOTIVISM, and PRESCRIPTIVISM. Applied eth- ics, as the name implies, consists of the application of normative ethical theories to practical moral problems (e.g., abortion). Among the major fields of applied ethics are bioethics, business ethics, legal ethics, and medical ethics.

Ethiopia \,e-the-'o-pe-3\ officially Federal Democratic Republic of Ethiopia formerly Abyssinia Country, eastern Africa. It is situated on the Horn of Africa, the continent’s easternmost projection. Area:

435,186 sq mi (1,127,127 sq km). Popula¬ tion (2005 est.): 73,053,000. Capital: Addis Ababa. The people are about one-third Amhara and one-third Oromo, with the bal¬ ance mostly Tigray, Afar, Somali, Saho, and

Agew. Languages: Amharic, Oromo. Religions: Christianity (predomi¬ nantly Ethiopian Orthodox; also Protestant), Islam, traditional beliefs. Cur¬ rency: birr. The landlocked country is mountainous in the north, with lowlands to the east and west. The central Ethiopian Plateau is split by the Great Rift Valley, which divides the eastern and western highlands. The cli¬ mate is temperate in the highlands, which are mainly savanna, and hot in the arid lowlands. Intensive farming and deforestation have led to severe erosion; this, along with periodic droughts, has produced periodic food shortages. The country’s once abundant wildlife has been decimated; many species are endangered. Ethiopia is one of the world’s poorest countries. Agriculture is mainly for subsistence, with cereals the main crop. Live¬ stock is also important. Coffee is the main export, followed by hides and skins. A new republic was established in 1995; it has two legislative houses, the chief of state is the president, and the head of government is the prime minister. Ethiopia, the Biblical land of Kush, was inhabited from earliest antiquity and was once under ancient Egyptian rule. Ge'ez-speaking agri¬ culturalists established the kingdom of Da’amat in the 7th century bc. After 300 bc they were superseded by the kingdom of Aksum, whose King Menilek I was, according to legend, the son of King Solomon and the Queen of Sheba. Christianity was introduced in the 4th century ad and became widespread (see Ethiopian Orthodox Church). Ethiopia’s prosper¬ ous Mediterranean trade was cut off by the Muslim Arabs in the 7th-8th century, and the area’s interests were directed southward. Contact with Europe resumed in the late 15th century with the arrival of the Portuguese. Modem Ethiopia began with the reign of Tewodros II, who began the con¬ solidation of the country. In the wake of European encroachment, the coastal region was made an Italian colony in 1889, but under Emperor Menilek II the Italians were defeated and ousted in 1896. Ethiopia prospered under his rule, and his modernization programs were continued by Emperor Haile Selassie in the 1930s. In 1936 Italy again gained control of the country and held it as part of Italian East Africa until 1941, when it was occupied by the British. Ethiopia incorporated Eritrea in 1952. In 1974 Haile Selassie was deposed, and a Marxist government, plagued by civil wars and famine, controlled the country until 1991. In 1993 Eritrea gained its independence, but there were continued border conflicts with it and neighbouring Somalia.

Ethiopian Orthodox church Independent Christian patriarchate in Ethiopia. Traditionally thought to have been founded by the preaching of the apostle Matthew or the eunuch of the Acts of the Apostles, the church was established in the 4th century by St. Frumentius and his brother

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Ethiopianism ► Etobicoke I 639

Aedesius. Based in Addis Ababa, the church adheres to Monophysite doctrine (see Monophysite heresy). It accepts the honorary primacy of the Coptic patriarch of Alexandria, who appointed its archbishops from the 12th century until 1959, when an autonomous Ethiopian patriarchate was established. Its customs include circumcision, rigorous fasting, and the participation of laypersons known as debtera, who perform liturgical music and dances and act as astrologers, scribes, and fortune-tellers. Its principal adherents are the Amhara and Tigray peoples of the northern and central highlands. See also Coptic Orthodox church.

Ethiopianism Religious movement among sub-Saharan Africans during the colonial era. It originated in South Africa in the 1880s, with the forma¬ tion of all-African Christian churches such as the Tembu tribal church and the Church of Africa. The term was first used by Mangena Mokone when he founded the Ethiopian Church in 1892. Africans resented the blatant rac¬ ism of European colonialists, who denied them advancement in religious and political hierarchies. They also wanted a version of Christianity rel¬ evant for Africa and a return to tribal life. Parallel developments occurred in Nigeria, Cameroon, Ghana, Kenya, and other locations. Ethiopian movements played some part in the Zulu rebellion of 1906 and the Nyasa- land rising of 1915. In the 1920s political aspirations moved away from religion and became tied to political parties and trade unions.

Ethiopic \,e-the-'o-pik\ languages Group of Semitic languages, spo¬ ken by more than 25 million people in Eritrea and Ethiopia. Ethiopic has been divided by linguists into North Ethiopic, comprising Ge’ez, Tigre, and Tigrinya (or Tigrai), and South Ethiopic, comprising the rest of the 22 languages. Ge’ez (or Ethiopic) is the oldest Ethiopian Semitic lan¬ guage, first attested in inscriptions from the kingdom of Aksum. It became the language of Christianity in the Aksumite period, and—though prob¬ ably extinct as a vernacular sometime before the 10th century ad —it remained the classical language of highland Ethiopian civilization and the liturgical language of the Ethiopian Orthodox church into the 20th century. Tigre has about 800,000 speakers in northern Eritrea, while Tigrinya has about 4 million speakers. The estimated 1.3 million Tigrinya speakers in Eritrea constitute about 50% of the country’s population. The most impor¬ tant South Ethiopic language is Amharic.

ethnic cleansing The creation of an ethnically homogenous geo¬ graphic area through the elimination of unwanted ethnic groups by depor¬ tation, forcible displacement, or genocide. Ethnic cleansing also has involved attempts to remove physical vestiges of the targeted group in the territory through the destruction and desecration of monuments, cemeter¬ ies, and houses of worship. Although some critics of the term have claimed that ethnic cleansing is simply a form of genocide, defenders of the usage have noted that, whereas the murder of an ethnic, racial, or reli¬ gious group is the primary intention of a genocidal policy, the chief goal of ethnic cleansing is the establishment of homogenous lands, which may be achieved by any of a number of methods including genocide. The term was widely employed in the 1990s to describe the brutal treatment of Bosniacs (Bosnian Muslims), ethnic Serbs in the Krajina region of Croatia, and ethnic Albanians in the Serbian province of Kosovo during the conflicts that erupted in the wake of the disintegration of Yugoslavia.

ethnic group Social group or category of the population that, in a larger society, is set apart and bound together by common ties of language, nation¬ ality, or culture. Ethnic diversity, the legacy of political conquests and migrations, is one aspect of the social complexity found in most contem¬ porary societies. The nation-state has traditionally been uneasy with ethnic diversity, and nation-states have often attempted to eliminate or expel eth¬ nic groups. Most nations today practice some form of pluralism, which usu¬ ally rests on a combination of toleration, interdependence, and separatism. The concept of ethnicity is more important today than ever, as a result of the spread of doctrines of freedom, self-determination, and democracy. See also CULTURE CONTACT; ETHNIC CLEANSING; ETHNOCENTRISM; RACE; RACISM.

ethnocentrism Tendency to interpret or evaluate other cultures in terms of one’s own. Generally considered a human universal, it is evident in the widespread practice of labeling outsiders as “savages” or “barbar¬ ians” simply because their societies differ from those of the dominant cul¬ ture. Early anthropologists often reflected this tendency, as did Sir John Lubbock, who characterized all nonliterate peoples as being without reli¬ gion, and Lucien Levy-Bruhl, who found them to have a “prelogical men¬ tality” because their worldview was unlike that of western Europe. The opposite of ethnocentrism is cultural relativism, the understanding of cul¬ tural phenomena within the context in which they occur.

ethnography \eth-'na-gro-fe\ Descriptive study of a particular human society. Contemporary ethnography is based almost entirely on fieldwork. The ethnographer lives among the people who are the subject of study for a year or more, learning the local language and participating in everyday life while striving to maintain a degree of objective detachment. He or she usually cultivates close relationships with “informants” who can pro¬ vide specific information on aspects of cultural life. While detailed writ¬ ten notes are the mainstay of fieldwork, ethnographers may also use tape recorders, cameras, or video recorders. Contemporary ethnographies have both influenced and been influenced by literary theory. See also Bronislaw Malinowski; cultural anthropology.

ethnomusicology Scholarly study of music as an aspect of culture. Taking an anthropological approach (it was originally called “compara¬ tive musicology”), it has tended to focus on non-Western music, particu¬ larly music of oral traditions. The field’s origins lie in the late 19th century with the work of scholars such as Francois-Joseph Fetis (1784-1871) and Carl Stumpf (1848-1936). Much work was motivated by the search for musical universals, under the assumption that prehistory could be stud¬ ied through research into “primitive” cultures of the present. Recogniz¬ ing that traditional societies were quickly disappearing with the modern world’s encroachment, ethnomusicologists soon put their highest priority on collection (by field recording, using the new recording technology) and transcription (using newly devised pitch calibrations). A number of clas¬ sification schemes for comparative analysis of different musics have been proposed, but the natural focus remains on diversity.

ethology \e-'tha-l3-je\ Study of animal behaviour. It is a combination of laboratory and field science, with strong ties to other disciplines (e.g., neuroanatomy, ecology, evolution). Though many naturalists have studied aspects of animal behaviour through the centuries, the modern science of ethology is considered to have arisen as a discrete discipline with the work in the 1920s of Nikolaas Tinbergen and Konrad Lorenz. Interested in the behavioral process rather than in a particular animal group, ethologists often study one type of behaviour (e.g., aggression) in various unrelated animals.

ethyl alcohol See ethanol

ethylene Simplest olefin (CH 2 CH 2 ), a colourless, flammable gas with a sweetish taste and odour. The petrochemical having the highest volume, it occurs in petroleum and natural gas but is usually produced by heating higher hydrocarbons (usually ethane and ethane-propane mixtures). Eth¬ ylene is polymerized to polyethylene either at high pressures and tempera¬ tures or by catalysis. It reacts with numerous other chemicals to produce ethanol, solvents, gasoline additives, antifreeze, detergents, and various plastics. In plants, ethylene is a hormone that inhibits growth and pro¬ motes leaf fall and fruit ripening.

ethylene glycol Ve-tho-.len-'gll-.koH Simplest member of the glycol family, also called 1,2-ethanediol (HOCH 2 CH 2 OH). It is a colourless, oily liquid with a mild odour and sweet taste. Widely used as an antifreeze in automobile cooling systems, it is also used in many other chemical pro¬ cesses. It and some of its derivatives are fairly toxic. Many dogs, cats, and wild animals are attracted by its sweetness and poisoned by drinking ethylene glycol antifreeze that has been carelessly discarded.

ethyne See acetylene

Etna, Mount Active volcano, eastern coast of Sicily, Italy. The highest active volcano in Europe, its elevation is more than 10,000 ft (3,200 m); its base has a circumference of about 93 mi (150 km). Mount Etna has repeatedly erupted over the centuries, most violently in 1669, when the lava flow destroyed villages on the lower slope and submerged part of the town of Catania. Activity was almost continuous in the decade following 1971, and in 1983 an eruption that lasted four months prompted authori¬ ties to explode dynamite in an attempt to divert lava flows. Mount Etna also experienced violent eruptions in 2001-02, prompting the Italian gov¬ ernment to declare a state of emergency.

Etobicoke \i-'to-b3-,kok\ Former city (pop., 2001: 338,117), southeast¬ ern Ontario, Canada. In 1998 it joined the cities of North York, Scarbor¬ ough, York, and Toronto and the borough of East York to become the City of Toronto. Etobicoke occupies an area of 48 sq mi (124 sq km); it was established in 1967 through the amalgamation of the township of Etobi¬ coke and several surrounding municipalities. Its name is derived from an Indian word meaning “place where the alders grow.”

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640 i Eton ► Eucken

Eton \'e-ton\ College Largest public school (independent secondary school) in England and one of the most prestigious. It is located in Eton, Berkshire. It was founded by Henry VI in 1440-41, the same year he founded King’s College, Cambridge. By tradition, 24 scholarships are reserved at Cambridge for Etonians. Boys enter Eton at about age 13. Most come from England’s wealthiest families, though 70 scholarships are awarded on the basis of competitive examination.

Etosha \e-'to-sh9\ National Park National reserve, northern Namibia. Covering some 8,598 sq mi (22,269 sq km), it centres on the Eto¬ sha Pan, a vast expanse of salt with lone salt springs, used by animals as salt licks. It has one of the largest populations of big-game species in the world, including lions, elephants, rhinoceros, elands, zebras, and springbok.

Etruria \i-'trur-e-9\ Ancient country, central Italy. It covered the region that now comprises Tuscany and part of Umbria. Etruria was inhabited by the Etruscans, who established a civilization by the 7th century bc. Their chief confederation, traditionally including 12 cities, developed a culture that reached its height in the 6th century bc. Etruscan power extended into northern and southern Italy at its peak, but the cities of Etruria were gradually absorbed by Rome during the 3rd century bc.

Etruscan Any member of an ancient people of Etruria, whose urban civilization reached its height in the 6th century bc. Their origins are obscure. By the 7th century they had incorporated all of Tuscany into their territory, and in the 6th century they pushed north to the Po River valley and became rulers of Rome. The Etruscans gave the city its first public works, including walls and a sewer system. By the end of the 6th cen¬ tury, pressure from other peoples in the region, including Greeks, Romans, and Gauls, weakened Etruria. The Romans expelled their dynasty in 509 bc. The Etruscans had a commercial and agricultural civilization and left a rich cultural heritage, including wall frescoes and realistic tomb por¬ traits. Many features of their culture were adopted by the Romans. See also Etruscan language; Etruscan religion.

Etruscan art (c. 8th-4th centuries bc) Art of the people of Etruria. The art of the Etruscans falls into three categories: funerary, urban, and sacred. Because of Etruscan attitudes toward the afterlife, most of the art that remains is funerary. Characteristic achievements are the wall frescoes— painted in two-dimensional style—and realistic terra-cotta portraits found in tombs. Bronze reliefs and sculptures are also common. Tombs found at Caere, carved underground out of soft volcanic rock, resemble houses. Urban architecture was another specialty; Etruscans were among the first in the Mediterranean to lay out cities with a grid plan, a practice copied by the Romans. In the sacred area, Etruscan temples had a deep front porch with columns and abundant terra-cotta roof sculptures, such as those from the temple at Veii (late 6th century). Etruscan art was influenced by Greek art and in turn influenced the development of realistic portraiture in Italy.

A detail from a fresco dating from the 5th century bc shows Etruscan musicians wearing tunics and sandals.

SCALA/ART RESOURCE, NEW VORK CITY

Etruscan language Language spoken by the ancient people of Etruria in what is now Italy. Its proposed relations with the Indo-European family have not been generally accepted, and Etruscan remains a linguistic isolate (i.e., unrelated to any other language). Known mainly from inscriptions

that date from the 7th century bc to the 1st century ad, Etruscan was written in an alphabet probably derived from one of the Greek alphabets.

Etruscan religion Beliefs and practices of the ancient people of Etru¬ ria in western Italy. The Etruscans believed that the gods manifested their nature and will in every aspect of the natural world, such that every bird and berry was a potential source of knowledge of the gods. The charac¬ teristics of their more than 40 deities were often vague or changeable, though some were later equated with the major Greek and Roman deities. Famous for divination, the Etruscans sought to learn the future, looking for divine signs in lightning, the livers of sacrificed animals, and the flights of birds. Belief in the afterlife led to the construction of elaborate tombs that were furnished as houses for the dead. Many features of Etruscan religion were later adopted by the Romans.

Etymander River See Helmand River

eubacteria V.yii-bak-'tir-e-sV Group consisting of the true bacteria, one of two major groups of the prokaryotes. The other is the archaebacteria, which are as different from eubacteria as either is from eukaryotes. The two groups are thought to have evolved separately from a common ances¬ tor early in earth’s history, and they differ in fundamental ways. Virtually all the familiar bacteria that cause diseases (e.g., E. cou, staphylococcus and salmonella strains, mycobacteria) or are important in food, agricul¬ ture, biotechnology, and other industrial activity (e.g., Lactobacillus, nitri¬ fying and denitrifying bacteria, and Lactobacillus and streptomyces strains) are eubacteria.

Euboea \yu-'be-9\ Greek Evvoia \'e-ve-a\ Island, Greece, in the Aegean Sea. The second largest of the Greek islands, it is about 110 mi (180 km) long and 4-30 mi (6-48 km) wide. It is mainly mountainous but includes the fertile plain of the Lilas River, which was in antiquity a famous horse-breeding region. Euboea is connected with Boeotia by a bridge built by the Chalcidians. It was dominated by Athens for much of the 5th century bc, while its main cities of Chalcis and Eretria were involved in the Persian and Peloponnesian wars. From 146 bc it was part of the Roman province of Macedon. Euboea was controlled by Venice from 1366, conquered by the Turks in 1470, and passed to Greece in 1830.

eucalyptus V.yu-ks-'lip-tasN Any of the more than 500 species of mostly very large trees in the genus Eucalyptus, in the myrtle family, native to Australia, New Zealand, Tasmania, and nearby islands. Many species are grown widely throughout the temperate regions of the world as shade trees or in forestry plantations. Because they grow rapidly, many species attain great height. The leaf glands of many species, especially E. salicifolia and E. globulus, contain a volatile, aromatic oil known as eucalyptus oil, used mostly in medicines. Eucalyptus wood is used extensively in Aus¬ tralia as fuel, and the timber is commonly used in buildings and fencing. The bark of many species is used in papermaking and tanning.

Eucharist Vyii-ks-rastV or Holy Communion or Lord's Supper

Christian rite commemorating the Last Supper of Jesus with his disciples. On the night before his death, according to the Christian scriptures, Jesus consecrated bread and wine and gave them to his disciples, saying “this is my body” and “this is my blood.” He also commanded his followers to repeat this rite in his memory, and the Eucharist traditionally involves con¬ secration of bread and wine by the clergy and their consumption by wor¬ shipers. Although celebrated spontaneously when the first Christians gathered to share a meal, the Eucharist quickly became a central part of the formal worship service and remained that way despite the many contro¬ versies over its nature and meaning. Intended as a means of fostering unity in the church, it has also been a source of division because of differing inter¬ pretations of its nature. In Roman Catholicism the Eucharist is a sacrament, and the bread and wine are thought to become the actual body and blood of Jesus through transubstantiation. Anglicans and Lutherans also emphasize the divine presence in the offering and recognize it as a sacrament, while others regard it as a memorial with largely symbolic meaning. Also con¬ troversial has been the belief in the Eucharist as a sacrifice, the renewed offering of Christ each time the rite is celebrated at the altar.

Eucken Voi-kanV, Rudolf Christoph (b. Jan. 5, 1846, Aurich, East Friesland—d. Sept. 14, 1926, Jena, Ger.) German philosopher. He taught primarily at the University of Jena (1874-1920). Distrusting abstract intel- lectualism and systematics, Eucken centred his philosophy upon actual human experience. He maintained that man is the meeting place of nature and spirit and that it is a human duty and privilege to overcome nature by incessant striving after the spiritual life. A strong critic of naturalism,

© 2006 Encyclopaedia Britannica, Inc.

Euclid ► Euler I 641

he held that humans are differentiated from the rest of the natural world by their possession of a soul, an entity that cannot be explained in terms of natural processes. He also was known as an interpreter of Aristotle. He won the Nobel Prize for Literature in 1908.

Euclid Vyu-kl3d\ (fl. c. 300 bc, Alexandria, Egypt) Greek mathematician of antiquity, known primarily for his highly influential treatise on geom¬ etry, the Elements. He founded a school in Alexandria during the reign of Ptolemy I. Little is known of his life, but there are many anecdotes. In the most famous, asked by Ptolemy if there is a shorter way to geometry than through his Elements , Euclid replies, “There is no royal road to geometry.” The Elements, based on the works of earlier mathematicians, is a brilliant synthesis of old and new. It has been a major influence on rational thought and a model for many philosophical treatises, and it has set a standard for logical thinking and methods of proof in the sciences. The starting point not just of Euclidean geometry but of an approach to reasoning, it is sometimes said to be the most translated, published, and studied work after the Bible.

Euclidean geometry Study of points, lines, angles, surfaces, and sol¬ ids based on Euclid’s axioms. Its importance lies less in its results than in the systematic method Euclid used to develop and present them. This axi¬ omatic method has been the model for many systems of rational thought, even outside mathematics, for over 2,000 years. From 10 axioms and pos¬ tulates, Euclid deduced 465 theorems, or propositions, concerning aspects of plane and solid geometric figures. This work was long held to consti¬ tute an accurate description of the physical world and to provide a suf¬ ficient basis for understanding it. During the 19th century, rejection of some of Euclid’s postulates resulted in two non-Euclidean geometries that proved just as valid and consistent.

Euclidean space In geometry, a two- or three-dimensional space in which the axioms and postulates of Euclidean geometry apply; also, a space in any finite number of dimensions, in which points are designated by coordinates (one for each dimension) and the distance between two points is given by a distance formula. The only conception of physical space for over 2,000 years, it remains the most compelling and useful way of mod¬ eling the world as it is experienced. Though non-Euclidean spaces, such as those that emerge from elliptic geometry and hyperbolic geometry, have led scientists to a better understanding of the universe and of mathemat¬ ics itself. Euclidean space remains the point of departure for their study.

eudaemonism Xyu-'de-mo-.ni-zonA In ethics, the view that the ultimate justification of virtuous activity is happiness. Virtuous activity may be conceived as a means to happiness, or well-being, or as partly constitu¬ tive of it (see teleological ethics). Ethical eudaemonism should be distin¬ guished from psychological eudaemonism, which holds that happiness is the ultimate motive of virtuous activity.

Eudocia Macrembolitissa Vyu-'do-sho-.mak-rom-.ba-b-'ti-soV (b. 1021, Constantinople, Byzantine Empire—d. 1096, Constantinople) Byz¬ antine empress and regent, called the wisest woman of her time. As the wife of Constantine X Ducas, she became regent for her three sons after his death (1067). To fend off the Seljuq Turks, she married a Cappado¬ cian general, Romanus Diogenes (later Romanus IV Diogenes). After his capture at the Battle of Manzikert (1071), Eudocia and her son Michael ruled jointly and deposed Romanus. After Michael succeeded to the throne, Eudocia entered a convent.

Eugene City (pop., 2000: 137,893), western Oregon, U.S. Located on the Willamette River, it was settled by Eugene Skinner in 1846. Named Eugene City in 1853, it grew as an agricultural and lumber centre with the arrival of the railroad in 1870. It is the site of the University of Oregon (founded 1872) and Northwest Christian College (1895). It is a tourist centre for the MacKenzie River recreational area and Willamette National Forest.

Eugene of Savoy orig. Francois-Eugene, prince de Savoie- Carignan (b. Oct. 18, 1663, Paris, France—d. April 24, 1736, Vienna, Austria) French-Austrian general. Born in Paris, he was the son of the count de Soissons, of the house of Savoy-Carignan, and of Olympe Man- cini (see Mancini family), niece of Jules Mazarin. Louis XIV severely restrained Eugene’s ambitions, prompting him to leave France and enter the service of Emperor Leopold I. He later served Joseph I and Charles VI. He quickly distinguished himself in battle and advanced in rank to impe¬ rial field marshal at age 29. He fought notably against the Turks in cen¬ tral Europe and the Balkans and against France in the War of the Grand

Alliance and the War of the Spanish Succession. With his friend the duke of Marlborough, he won the important victory at the Battle of Blenheim (1704) and ousted the French from Italy. In 1718 he won a great triumph over the Turks, taking the city of Belgrade. He later served as governor in the Austrian Netherlands (1714-24). An outstanding strategist and an inspired leader, he was regarded as one of the greatest soldiers of his gen¬ eration.

eugenics \yu-'je-niks\ Study of human improvement by genetic means. The first thorough exposition of eugenics was made by Francis Galton, who in Hereditary Genius (1869) proposed that a system of arranged marriages between men of distinction and women of wealth would even¬ tually produce a gifted race. The American Eugenics Society, founded in 1926, supported Galton’s theories. U.S. eugenicists also supported restric¬ tion on immigration from nations with “inferior” stock, such as Italy, Greece, and countries of eastern Europe, and argued for the sterilization of insane, retarded, and epileptic citizens. Sterilization laws were passed in more than half the states, and isolated instances of involuntary steril¬ ization continued into the 1970s. The assumptions of eugenicists came under sharp criticism beginning in the 1930s and were discredited after the German Nazis used eugenics to support the extermination of Jews, blacks, and homosexuals. See also genetics, race, social Darwinism.

Eugenie \oe-zha-'ne\ orig. Eugenia Maria de Montijo de Guzman (b. May 5, 1826, Granada, Spain—d. July 11, 1920, Madrid) Wife of Napoleon III and empress of France (1853-70). Daughter of a Spanish noble, she married Napoleon III in 1853 and came to have an important influence on her husband’s foreign policy. As a devoted Roman Catholic, she favored a strong papacy and supported Ultramontane causes. She also encouraged French opposition to a Prussian candidate for the Spanish throne in the controversy that precipitated the Franco-Prussian War. After the French defeat at Sedan, she joined her family in exile in England.

Eugenius \yu-'je-ne-os\ III orig. Bernard of Pisa (b. near Pisa—d. July 8, 1153, Tivoli, near Rome; beatified 1872; feast day July 8) Pope (1145-53). A Cistercian abbot, he was elected pope when Rome was on the verge of anarchy, and in 1146 he was forced into exile. While in France he supported Louis VII’s intention to launch the Second Crusade to free Edessa, an effort that ended in failure. He returned to Italy (1148), but the hostility of the Senate often kept him away from Rome. In the Treaty of Constance (1153) Eugenius fixed conditions for the coronation of Fred¬ erick I Barbarossa but died before it could take place.

euhemerism Nyii-'he-mo-.ri-zomX Attempt to find a historical basis for mythical beings and events. It takes its name from Euhemerus (fl. 300 bc), a Greek scholar who examined popular mythology in his Sacred His¬ tory and asserted that the gods originated as heroes or conquerors who were admired and later deified. Though modem scholars do not accept euhemerism as the sole explanation for the origin of gods, it is thought to be valid in some cases.

eukaryote \yu-'kar-e-,ot\ Any organism composed of one or more cells, each of which contains a clearly defined nucleus enclosed by a membrane, along with organelles (small, self-contained, cellular parts that perform specific functions). The organelles include mitochondria, CHLO- roplasts, a Golgi apparatus, an endoplasmic reticulum, and lysosomes. All organisms except bacteria are eukaryotes; bacteria are prokaryotes.

Eulenspiegel Vofiil-on-.shpe-gslA English Voil-on-.spe-golV Till Ger¬ man peasant trickster of folk and literary tales. The historical Till is said to have died in 1350; anecdotes associated with his name were printed c. 1500 in Low German and from 1515 in High German. In the tales the stupid yet cunning peasant demonstrates his superiority to the narrow, dishonest, condescending townsmen, as well as to the clergy and nobil¬ ity. The tales were translated into Dutch and English (c. 1520), French (1532), and Latin (1558).

Euler Voi-laA, Leonhard (b. April 15, 1707, Basel, Switz.—d. Sept. 18, 1783, St. Petersburg, Russia) Swiss mathematician. In 1733 he suc¬ ceeded Daniel Bernoulli (see Bernoulli family) at the St. Petersburg Acad¬ emy of Sciences. There he developed the theory of trigonometric and logarithmic functions and advanced mathematics generally. Under the patronage of Frederick the Great, he worked at the Berlin Academy for many years (1744-66), where he developed the concept of function in mathematical analysis and discovered the imaginary logarithms of nega¬ tive numbers. Throughout his life he was interested in number theory. In

© 2006 Encyclopaedia Britannica, Inc.

642 i Euler's formula > Europa

addition to inspiring the use of arithmetic terms in writing mathematics and physics, Euler introduced many symbols that became standard, including £ for summation; Jn for the sum of divisors of ir, e for the base of the natural logarithm; a, b, and c for the sides of a triangle with A, B, and C for the opposite angles; f[x) for a function; n for the ratio of the circumference to the diameter of a circle; and i for V-l. He is considered one of the greatest mathematicians of all time.

Euler's formula Either of two important mathematical theorems of Leonhard Euler. The first is a topological invariance (see topology) relat¬ ing the number of faces, vertices, and edges of any polyhedron. It is writ¬ ten F + V = E + 2, where F is the number of faces, V the number of vertices, and E the number of edges. A cube, for example, has 6 faces, 8 vertices, and 12 edges, and satisfies this formula. The second formula, used in trigonometry, says e “ = cos x + /sin x where e is the base of the natural logarithm and / is the square root of -1 (see irrational number). When x is equal to n or 2k, the formula yields two elegant expressions relating n, e, and /: = -1 and e 2lli = 1.

Eumenes Vyii-ma-.nezX II (d. 160/159 bc) King of Pergamum (197 bc-c. 160). He continued the policy of his father, Attalus I Soter, of coopera¬ tion with Rome. He helped defeat Antiochus III, thus enlarging his realm. He brought his kingdom to its height and made it a great centre of Greek culture; in particular, he is credited with constructing nearly all the pub¬ lic buildings and sculpture on the Pergamum acropolis. He was suspected of disloyalty in the Roman struggle against Perseus; Rome subsequently withdrew its support, and Eumenes’s power and the glory of Pergamum declined. His brother Attalus II became coruler c. 160 bc.

Eumolpus \yu-'mal-p3s\ Mythological ancestor of the priestly class, the Eumolpids, at Eleusis in ancient Greece. His name means “sweet singer.” Three divergent identities for him exist in legend: he is the father, son, or pupil of Musaeus, a mythical singer connected with Orpheus, in one; an originator of the Eleusinian Mysteries in another; and a king of Thrace and son of Poseidon in a third.

eunuch Vyii-nokV Castrated human male. From remote antiquity on, eunuchs were employed in the Middle East and China as guards and ser¬ vants in harems or other women’s quarters and as chamberlains to kings. The eunuchs’ confidential position frequently enabled them to exercise an important influence over their royal masters. Many of the patriarchs of Constantinople during Byzantine times were eunuchs. Eunuch advisers disappeared as a class only with the end of the Ottoman Empire. See also CASTRATO.

euonymus \yu-'a-n3-m9s\ Any of about 170 species of shrubs, woody climbers, and small trees that make up the genus Euonymus (family Celas- traceae), native to temperate Asia, North America, and Europe, including many popular landscape ornamental shrubs and ground covers. The winged spindle tree ( E. alata ), also called burning bush, is a handsome shrub with corky winged stems. Wood of the common spindle tree {E. europaea) is used for pegs and spindles; several varieties are grown as ornamentals.

euphonium \yu-'fo-ne-9m\ or tenor tuba Large valved brass instru¬ ment, the leading lower-pitched instrument in military bands. It developed from the valved bugle and cornet in Germany c. 1840. It has four valves and a wide conical bore resembling the tuba’s. Its range is an octave below the trumpet and comet. It is played either vertically or with the bell fac¬ ing forward. The very similar baritone has the same range and transpo¬ sition and is distinguished only by its narrower bore. Both are essential members of bands of all kinds and are often given significant solo roles.

euphorbia See spurge

Euphranor \yu-'fra-nor\ (b. c. 390 bc, Greece—d. c. 325, Athens?) Greek sculptor and painter active in Athens. The only surviving work identified as his is the fragments of a colossal marble statue of Apollo (c. 330 bc) found in the agora at Athens. Other recorded (but lost) works suggest that he was one of the foremost Athenian artists of the mid 4th century bc. He also wrote treatises on proportion and colour.

Euphrates \yu-'fra-tez\ River Turkish Firat Nehri \f3-'rat-ne-'re\ Arabic Nahr al Furat River, Middle East. The largest river in South¬ west Asia, it rises in Turkey and flows southeast across Syria and through Iraq. Formed by the confluence of the Karasu and the Murat rivers in the high Armenian plateau, the Euphrates descends between major ranges of the Taurus Mountains to the Syrian plateau. It then flows through western

and central Iraq to unite with the Tigris and continues, as Shatt al-Arab, to the Persian Gulf. In all, it is 1,740 mi (2,800 km) long. Its valley was heavily irrigated in ancient times, and many great cities, some of whose ruins remain, lined its banks. With the Tigris, it defines an area known historically as Mesopotamia.

Euphronius \yu-'fro-ne-9s\ or Euphronios (fl. c. 520^-70 bc, Ath¬ ens, Greece) Greek vase painter and potter. His signature has been iden¬ tified on 20 vessels, 8 that he signed as painter and 12 as potter. He was an outstanding early proponent of red-figure pottery. His best-known work as a painter is a krater in the Louvre depicting Herakles wrestling Antaeus. As a potter, he worked with the finest vase painters of his time. His great¬ est rival was Euthymides.

Eure River \'oer\ River, northern France. From its source in the Perche Hills it flows chiefly through agricultural and wooded regions on its 140-mi (225-km) course, passing through Chartres below the cathedral, which is located on high ground on its left bank. It joins the Seine above Rouen.

Euripides Vyu-'ri-po-.dezN (b. c. 484 bc, Athens—d. 406 bc, Macedonia) Greek playwright. With Aeschylus and Sophocles, he is recognized as one of Athens’s three great tragic dramatists. An associate of the philosopher Anaxagoras, he expressed his questions about Greek religion in his plays. Beginning in 455, he was repeatedly chosen to compete in the dramatic festival of Dionysus; he won his first victory in 441. He competed 22 times, writing four plays for each occasion. Of his 92 plays, about 19 survive, including Medea (431), Hippolytus (428), Electra (418), The Trojan Women (415), Ion (413), Iphigenia at Aulis (406), and The Bac- chae (406). Many of his plays include prologues and rely on a DEUS ex machina. Unlike Aeschylus and Sophocles, Euripides made his characters’ tragic fates stem almost entirely from their own flawed natures and uncon¬ trolled passions. In his plays chance, disorder, and human irrationality and immorality frequently result in apparently meaningless suffering that is looked on with indifference by the gods.

Euripus See Chalkis

Euripus \yu-'ri-p9s\ Strait or Evripos Ve-vre-,p6s\ Strait Narrow strait in the Aegean Sea. Located between the Greek island of Euboea and the mainland of central Greece, it is 5 mi (8 km) long and varies from 130 ft (40 m) to 1 mi (1.6 km) in width. It has strong tidal currents that reverse directions seven or more times a day, a phenomenon still not fully under¬ stood. The main port on the strait is Chalkis, an important trading centre since the times of ancient Greece. A 130-ft (40-m) movable bridge spans the strait at Chalkis, replacing earlier structures that dated to 411 bc.

euro Single currency of 12 countries of the European Union (EU), includ¬ ing Germany, France, and Italy. The euro was adopted as a unit of exchange in January 1999. Those who advocated the currency believed it would strengthen Europe as an economic power, increase international trade, simplify monetary transactions, and lead to pricing equality throughout Europe. Euro currency notes and coins were introduced in January 2002 and became the sole national currency in all participating countries by March 1. Britain and Sweden decided not to adopt the euro immediately, and voters in Denmark rejected it.

Eurocommunism Trend among European communist parties toward independence from Soviet Communist Party doctrine in the 1970s and ’80s. The term, coined in the mid-1970s, received wide publicity after the pub¬ lication of Santiago Carrillo’s Eurocommunism and the State (1977). The Eurocommunist movement rejected the Soviet doctrine of one monolithic world communist movement and advocated instead that each country’s communist party base its policies on the traditions and needs of its own country. With Mikhail Gorbachev’s encouragement, all communist parties took independent courses in the late 1980s. Most of the European com¬ munist parties declined after the breakup of the Soviet Union.

Eurodollar U.S. dollar that has been deposited outside the U.S., espe¬ cially in Europe. Foreign banks holding Eurodollars are obligated to pay in U.S. dollars when the deposits are withdrawn. Most Eurodollars are used to finance trade, but many central banks also operate in the Euro¬ dollar market. See also currency, foreign exchange.

Europa \yu-'ro-p3\ In Greek mythology, the daughter either of Phoenix or of Agenor, king of Phoenicia. Her beauty inspired the love of Zeus, who approached her in the form of a white bull and carried her off across the sea to Crete. After bearing Zeus three sons, she married the king of

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Europe ► European Economic Community I 643

Crete, who adopted her sons. They grew up to become King Minos of Crete, King Rhadamanthus of the Cyclades, and Prince Sarpedon of Lycia. On Crete she was worshiped under the name Hellotis. The continent of Europe is named for her.

Europe Second smallest continent on Earth. It is bordered by the Arctic Ocean, the Atlantic Ocean, and the Mediterranean, Black, and Caspian seas. The continent’s eastern boundary runs along the Ural Mountains and the Ural River. Its area includes numerous islands, archipelagoes, and pen¬ insulas. Indented by bays, fjords, and seas, continental Europe’s irregu¬ lar coastline is about 24,000 mi (38,000 km) long. Area: 4,000,000 sq mi (10,400,000 sq km). Population (2001 est.): 666,498,000. The greater part of Europe combines low elevations with low relief; about three-fifths of the land is below 600 ft (180 m) above sea level, and another one-third is between 600 and 3,000 ft (180 and 900 m). The highest points are in the mountain systems crossing the southern part of the continent, includ¬ ing the Pyrenees, Alps, Apennines, Carpathians, and Balkan Mountains. A well-watered continent with many rivers, Europe has few sizable lakes. Glaciers cover an area of about 44,800 sq mi (116,000 sq km), mostly in the north. Roughly one-third of Europe is arable, and about half of that land is devoted to cereals, principally wheat and barley. One-third is for¬ ested. Europe was the first of the world’s regions to develop a modern economy based on commercial agriculture and industry, and it remains one of the world’s major industrial regions, with average annual income per capita among the world’s highest. The people of Europe constitute about one-seventh of the world’s population. Most of the continent’s approximately 60 native languages belong to either the Romance, Ger¬ manic, or Slavic language groups. Europe’s population is overwhelmingly Christian. Modem humans supplanted the scanty Neanderthal population in Europe about 40,000 years ago, and by the beginning of the 2nd mil¬ lennium bc the general population groups that would become the histori¬ cal peoples and countries of Europe were in place. The Greek civilizations were the earliest in Europe, and in the Classical period the Greeks were a conduit for the advanced civilizations of the Middle East, which, along with the unique Greek contribution, laid the foundation for European civilization. By the mid-2nd century bc the Greeks had come under Roman control, and the vast Roman Empire brought to the conquered parts of Europe the civilization the Greeks had begun. It was through the Romans that Christianity penetrated into Europe. The Roman Empire in the West finally collapsed in the 5th century ad, which led to an exten¬ sive breakdown of Classical civilization. This civilization was not to be revived until the Renaissance (15th-16th centuries), which began the mod¬ em European traditions of science, exploration, and discovery. The Prot¬ estant Reformation of the 16th century ended the dominance of the Roman Catholic church over western and northern Europe, and the Enlightenment period of the 17th and 18th centuries stressed the primacy of reason. In the late 18th century, Enlightenment ideals helped spur the French Revo¬ lution, which toppled Europe’s most powerful monarchy and spearheaded the movement toward democracy and equality. The late 18th century also marked the beginning of the Industrial Revolution, which led to Europe’s military and political dominance over much of the world for the next cen¬ tury. In the early 20th century the European powers were divided in World War I, which led to the effective end of monarchy in Europe and created a host of new countries in central and eastern Europe. World War II marked the passing of world power from the states of western Europe and was followed by the rise of communism in eastern Europe, with the Soviet Union and its satellites sharply dividing the continent. The Soviet Union collapsed in the late 20th century, leading to a general demise of com¬ munism throughout the continent. Soviet satellites became independent, and most began to democratize; East and West Germany were reunified; and Yugoslavia and its successor states were devastated by ethnic conflict (see Kosovo conflict; Bosnian conflict). See also European Union; NATO. See map on following page.

Europe, Council of Organization of more than 40 European states formed to promote European unity, protect human rights, and facilitate social and economic progress. Established in 1949 by 10 western Euro¬ pean states, it has devised international agreements on human rights and established a number of special bodies and expert committees on social, legal, and cultural issues. It is headquartered in Strasbourg, France. (The Council of Europe should not be confused with the European Council, which is a policy-making body of the European Union.)

European Aeronautic Defence and Space Co. (EADS) Euro¬ pean aerospace company that is one of the world’s largest. It was formed

(2000) from the merger of Aerospatiale Matra of France, DaimlerChrysler Aerospace (Dasa) of Germany, and Construcciones Aeronauticas S.A. (CASA) of Spain. It holds an 80% share in the European airplane manu¬ facturer Airbus S.A.S. and is responsible for the final assembly of Airbus aircraft. It has a controlling interest in the trinational venture Astrium (created 2000), whose facilities in France, Germany, and Great Britain cover a broad range of the space business from ground systems and launch vehicles to satellites and orbital infrastructure. Its Eurocopter subsidiary produces military and civil helicopters. It also has stakes in Arianespace, which markets the commercial services of Ariane launch vehicles; the Eurofighter consortium to develop a multirole combat aircraft; and the French aerospace firm Dassault.

European Atomic Energy Community (Euratom) International organization established in 1958 to form a common market for develop¬ ing peaceful uses of atomic energy. It originally had six members; it now includes all members of the European Union. Among its aims were to facilitate the establishment of a nuclear energy industry on a European rather than a national scale, coordinate research, encourage construction of power plants, establish safety regulations, and establish a common market for trade in nuclear equipment and materials. In 1967 its govern¬ ing bodies were merged into the European Community.

European Coal and Steel Community (ECSC) Administrative agency designed to integrate the coal and steel industries of France, West Germany, Italy, Belgium, the Netherlands, and Luxembourg. It originated in the plan of Robert Schuman (1950) to establish a common market for coal and steel by those countries willing to submit to an independent authority. Created in 1952, the ECSC came to include all members of the European Union. It initially removed barriers to trade in coal, coke, steel, pig iron, and scrap iron; it later supervised the reduction of its members’ excess production. In 1967 its governing bodies were merged into the European Community. When the treaty expired in 2002, the ECSC was dis¬ solved.

European Community (EC) Organization formed in 1967 with the merger of the European Economic Community, European Coal and Steel Community, and European Atomic Energy Community. The merger created a single Commission of the European Community and a single Council of Ministers. Other executive, legislative, and judicial bodies also were col¬ lected under the umbrella of the EC. In 1993 the EC became the basis of the European Union, and the European Economic Community was renamed the European Community.

European Court of Justice Judicial branch of the European Union (EU), established in 1958 to ensure the observance of international agree¬ ments negotiated by predecessor organizations of the EU. Headquartered in Luxembourg, it reviews the legality of the acts of EU executive bod¬ ies and rules on cases of civil law between member states or private par¬ ties. It can invalidate the laws of EU members when they conflict with EU law. Its bench, which is appointed by member governments, consists of 25 judges and 8 advocates-general. Prior to 2004, the ECJ met as a full chamber for all cases, but it now may sit as a “grand chamber” of 11 judges. See also International Court of Justice.

European Defense Community (EDC) Attempt by western Euro¬ pean powers, with U.S. support, to counterbalance the overwhelming con¬ ventional military ascendancy of the Soviet Union in Europe by creating a supranational European army, including West German forces. A treaty was concluded in 1952, but the French parliament’s refusal to ratify the treaty in 1954 brought an end to the project. One consequence of the French action was the decision in 1955 to rearm West Germany and allow its entry into NATO. In 1955 the EDC was replaced by the Western Euro¬ pean Union.

European Economic Community (EEC) later European Com¬ munity (EC) known as the Common Market Association of Euro¬ pean countries designed to promote European economic unity. It was established by the Treaty of Rome in 1957 to develop the economies of the member states into a single common market and to build a political union of the states of western Europe. The EEC also sought to establish a single commercial policy toward nonmember countries, to coordinate transpor¬ tation systems, agricultural policies, and general economic policies, to remove measures restricting free competition, and to assure the mobility of labour, capital, and entrepreneurship among member states. The liber¬ alized trade policies it sponsored from the 1950s were highly successful in increasing trade and economic prosperity in western Europe. In 1967

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European Free Trade Association ► Evans I 645

its governing bodies were merged into the European Community. In 1993 the EEC was renamed the European Community (EC); it is now the prin¬ cipal organization within the European Union.

European Free Trade Association (EFTA) International organi¬ zation whose puipose is to remove barriers to trade in industrial goods among its members. The EFTA’s current members are Iceland, Liechtein- stein, Norway, and Switzerland. It was formed in 1960 by Austria, Den¬ mark, Norway, Portugal, Sweden, Switzerland, and Britain as an alternative to the European Economic Community (EEC). Some of those countries later left the EFTA and joined the EEC. In the 1990s Iceland, Liechtenstein, and Norway joined the European Economic Area, which also included all members of the European Union. Each country in the EFTA maintains its own commercial policy toward countries outside the group.

European Parliament Legislative assembly of the European Union (EU). Inaugurated in 1958 as the Common Assembly, the European Par¬ liament originally consisted of representatives selected by the national parliaments of member countries. Beginning in 1979, members of the Parliament, who now number more than 700, were elected by direct uni¬ versal suffrage to terms of five years. The number of members per coun¬ try varies depending on population. The Parliament’s leadership is shared by a president and 14 vice presidents, elected for 30-month terms. The EU Council of Ministers, which represents the member states, consults the Parliament, which is empowered to discuss whatever matters it wishes. The Parliament’s powers were expanded with passage of the Maastricht Treaty (1993). Although it has veto power in most areas relating to eco¬ nomic integration and budgetary policy, it remains subordinate to the Council of Ministers and does not function with the authority of a national legislature such as the U.S. Congress or the British House of Commons.

European Space Agency (ESA) French Agence Spatiale Europeenne Western European space and space-technology research organization headquartered in Paris. It was founded in 1975 from the merger of the European Launcher Development Organisation (ELDO) and the European Space Research Organisation (ESRO), both established in 1964. Members are Austria, Belgium, Britain, Denmark, Finland, France, Germany, Ireland, Italy, The Netherlands, Norway, Portugal, Spain, Swe¬ den, and Switzerland. Canada, through a special cooperative agreement, participates in some projects. The ESA developed the Ariane series of space launch vehicles, and it supports a launch facility in French Guiana. It has launched a system of meteorological satellites (Meteosat) as well as the Giotto space probe, which examined the nucleus of Halley's Comet, and Hipparcos, a satellite that measured the PARALLAXes, positions, and proper motions of more than 100,000 stars. It is also a participant in the construction of the International Space Station.

European Union (EU) Organization of European countries, formed in 1993 to oversee their economic and political integration. It was created by the Maastricht Treaty and ratified by all members of the European Com¬ munity (EC), out of which the EU developed. The successful EC had made its members more receptive to greater integration and provided a frame¬ work for unified action by member countries in security and foreign policy and for cooperation in police and justice matters. In pursuit of its major goal to create a common monetary system, the EU established the euro, which replaced the national currencies of 12 of the 15 EU members in 2002. Originally confined to western Europe, the EU enlarged to include several central and eastern European countries in the early 21st century. The EU’s principal institutions are the European Community, the Coun¬ cil of Ministers (a forum for individual ministries), the European Com¬ mission (an administrative bureaucracy), the European Parliament, the European Court of Justice, and the European Central Bank.

Eurotunnel See Channel Tunnel

eurypterid \yu-'rip-t3-rad\ Member of an extinct order (Eurypterida) of arthropods, similar in body plan to the horseshoe crab, that lived c. 505-245 million years ago. Frequently referred to as giant scorpions, most eurypterids were small, although Pterygotus buffaloenis, a species from the Silurian period, was the largest arthropod ever known, reaching a length of about 10 ft (3 m). The eurypterids lived in brackish waters. Some were predators; others were probably bottom-dwelling scavengers.

eurythmics \yu-'rith-miks\ Method of musical training for young chil¬ dren. Eurythmics was developed by Swiss musician Emile Jaques-Dalcroze in the early years of the 20th century. It called for movements of the arms

and legs in specific ways in response to changing rhythms and pitches. The initial aim was to encourage a physical response to music in the young, in the hope that it would educate them musically. Very popular in the early 20th century, it has declined in recent decades.

Eusebius of Caesarea \yu-'se-be-9s...,se-z9- , re-3\ (fl. 4th century, Caesarea Palestinae, Palestine) Bishop and historian of early Christianity. Baptized and ordained at Caesarea in Palestine, he may have been impris¬ oned during the Roman persecutions. His fame rests on his Ecclesiasti¬ cal History (312-324), which preserves portions of works no longer extant. He became bishop of Caesarea c. 313. Accused of Arianism, he was excommunicated in 325 but was soon exonerated by the Council of Nicaea. He was a staunch supporter of Constantine I’s attempts to unify and standardize Christian doctrine, and his writings include the Life of Constantine.

euthanasia Vyii-tho-'na-zhoV or mercy killing Painless killing of a person who has a painful, incurable disease or incapacitating disorder. Most legal systems consider it murder, though in many jurisdictions a physician may lawfully decide not to prolong the patient’s life or may give drugs to relieve pain even if they shorten the patient’s life. Associa¬ tions promoting legal euthanasia exist in many countries. The legalization movement has gained ground with advancing medical technology, which has been used to prolong the lives of patients who are enduring extreme suffering or who are comatose or unable to communicate their wishes. Euthanasia was legalized in The Netherlands in 2001 and in Belgium in 2002. In 1997 Oregon became the first state in the U.S. to decriminalize physician-assisted suicide.

Euthymides Vyu-'thi-mo-.dezV (fl. c. 515-500 bc, Athens, Greece) Greek vase painter. He was a contemporary of Euphronius. His signature has been found on eight extant vases, six that he signed as a painter and two as a potter. A proponent of red-figure pottery, he was noted for his mastery of foreshortening and studies in movement. The amphora now in Munich’s Antiquities Museum showing foreshortened figures in three- quarter view is an outstanding example of his draftsmanship.

eutrophication Vyu-.tro-fo-'ka-shonV Gradual increase in the concen¬ tration of phosphorus, nitrogen, and other plant nutrients in an aging aquatic ecosystem such as a lake. The productivity or fertility of such an ecosystem increases as the amount of organic material that can be bro¬ ken down into nutrients increases. This material enters the ecosystem mainly through runoff that carries debris. Water blooms often develop on the surface, preventing the light penetration and oxygen absorption nec¬ essary for underwater life. See also water pollution.

Evagoras \i-'va-g3-ros\ (d. 374 bc) King of Salamis, Cyprus (c. 410- 374). He pursued a policy of friendship with Athens and the promotion of Hellenism. He secured Persian aid for Athens against Sparta. With help from Athens and Egypt, he extended his rule over most of Cyprus and part of Anatolia. Relations with Persia later became hostile, and he was defeated by Persia in 381. Though he remained king of Salamis in name, he was in fact a vassal of Persia. He was assassinated by a eunuch.

evangelicalism X.e-.van-'je-li-ko-.li-zomX Protestant movement that stresses conversion experiences, the Bible as the only basis for faith, and evangelism at home and abroad. The religious revival that occurred in Europe and America during the 18th century was generally referred to as the evangelical revival. It included Pietism in Europe, Methodism in Brit¬ ain, and the Great Awakening in America. In London in 1846, the Evan¬ gelical Alliance was organized by evangelical Christians from several denominations and countries. In the U.S., the movement grew, in part, because of the popularity of preachers such as Billy Graham, the creation of institutions such as Wheaton College, the publishing of the periodical Christianity Today , and the founding of professional organizations and associations, such as the National Association of Evangelicals (1942). Developing a sense of international and interdenominational unity, evan¬ gelicals formed the World Evangelical Fellowship (WEF) in 1951. More than 110 regional and national organizations and some 110 million people are affiliated with the WEF, now headquartered in Singapore. See Chris¬ tian fundamentalism; Pentecostausm.

Evans, Sir Arthur (John) (b. July 8, 1851, Nash Mills, Hertfordshire, Eng.—d. July 11, 1941, Youlbury, near Oxford, Oxfordshire) British archaeologist. Son of the archaeologist Sir John Evans, he served as a curator (1884-1908) at Oxford’s Ashmolean Museum. Beginning in 1899 he devoted several decades to excavating the ruins of the ancient city of

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646 i Evans ► evapotranspiration

Knossos in Crete, uncovering evidence of a sophisticated Bronze Age civilization that he named Minoan. His work, one of archaeology’s major achievements, greatly advanced the study of European and eastern Medi¬ terranean prehistory. He published his definitive account in The Palace of Minos , 4 vol. (1921-36).

Evans, Bill orig. William John Evans (b. Aug. 16, 1929, Plainfield, N.J., U.S.—d. Sept. 15, 1980, New York, N.Y.) U.S. pianist and com¬ poser, one of the most influential musicians in modern jazz. Evans was classically trained and influenced by pianists Bud Powell, Horace Silver, and Lennie Tristano. His subtle harmonies and lyrical melodic sensitivity were particularly well suited to modal improvisation, demonstrated on the landmark Miles Davis recording Kind of Blue (1959). As leader of his own trio, Evans established near-telepathic communication with his fellow musicians, creating music of rare depth and introspection. His best-known composition is “Waltz for Debby.”

Evans, Dame Edith (Mary) (b. Feb. 8, 1888, London, Eng.—d. Oct. 14, 1976, Cranbrook, Kent) British actress. She made her stage debut as Cressida in William Shakespeare’s Troilus and Cressida (1912) and joined the Old Vic company in 1925.

One of the finest actresses of the 20th century, she appeared in London and on Broadway in plays by Shakes¬ peare, George Bernard Shaw, and Noel Coward. She played Lady Bracknell in Oscar Wilde’s The Importance of Being Earnest on stage and screen (1952). Her other films include Look Back in Anger (1959), Tom Jones (1963), The Chalk Garden (1964), and The Whisperers

(1967).

Evans, Frederick H(enry) (b.

June 26, 1853, London, Eng.—d.

June 24, 1943, London) British pho¬ tographer. He first attracted attention as a popular London bookseller and champion of the work of George Bernard Shaw and Aubrey Beardsley. Around 1890 he began to photograph English and French cathedrals, and from 1898 he devoted himself exclusively to photography. His belief that only static views of idealized beauty were worth photographing clashed with the early 20th-century tendency to photograph fleeting images, but his architectural photographs are considered among the world’s finest.

Evans, George Henry (b. March 25, 1805, Bromyard, Herefordshire, Eng.—d. Feb. 2, 1856, Granville, N.J., U.S.) British-born U.S. newspa¬ per editor and social reformer. He immigrated to the U.S. in 1820. In 1829 he founded the Working Man’s Advocate, the first major U.S. labour news¬ paper, and cofounded the Workingmen's Party. He organized the National Reform Association to lobby Congress for free homesteads in the West, arguing that the availability of free land would draw away excess work¬ ers from the East and keep wages high for those who remained (see Homestead Movement). His efforts led to the passage of the Homestead Act in 1862. He also fought for the abolition of slavery and advocated equal rights for women.

Evans, Maurice (Herbert) (b. June 3, 1901, Dorchester, Dorset, Eng.—d. March 12, 1989, Rottingdean, East Sussex) British-born U.S. actor. He made his professional stage debut in 1926 and achieved his first success in Journey’s End (1929). He moved to the U.S. in 1935 and tri¬ umphed in Shakespearean roles on Broadway. During World War II he entertained U.S. troops with a short version of Hamlet. He later starred in Broadway revivals of four George Bernard Shaw comedies, notably Man and Superman (1947). His greatest Broadway hit was Dial M for Murder (1952). He starred in a television production of Macbeth (1961, Emmy Award) and appeared in 17 films, including Rosemary’s Baby

(1968).

Evans, Oliver (b. Sept. 13, 1755, near Newport, Del.—d. April 15, 1819, New York, N.Y., U.S.) U.S. inventor. Evans began early to apply himself to industrial problems. He invented an improved carding device for use in the newly mechanized production of textiles. In 1784 he built a flour mill, for which he created the first continuous production line in

any industry: all movement was automatic, power being supplied by waterwheels, and grain was passed by conveyors and chutes through the stages of milling and refining to emerge as finished flour. His high- pressure steam engine (patented 1790) deserves to share the credit for the invention often given solely to Richard Trevithick. His Amphibious Digger (1805), a steam-engine scow that could run on both land and water, was the first powered road vehicle to operate in the U.S. His Mars Iron Works (founded 1806) made more than 100 steam engines for use with screw presses for processing cotton, tobacco, and paper.

Evans, Walker (b. Nov. 3, 1903, St. Louis, Mo., U.S.—d. April 10, 1975, New Haven, Conn.) U.S. photographer. He was influenced early by the photographs of Eugene Atget. In 1934 his images of New England architecture were exhibited in the first one-man photographic show at the Museum of Modern Art. From 1935 he photographed rural victims of the Great Depression for the Farm Security Administration; these images were published in American Photographs (1938). He collaborated with James Agee to document the life of Alabama sharecroppers in Let Us Now Praise Famous Men (1941). Evans’s photographs appeared without titles or comment, in a section separate from Agee’s text, yet the whole con¬ stitutes one of the finest collaborations between a photographer and a writer. He was later an editor of Fortune magazine (1945-65) and a pro¬ fessor at Yale University (1965-74).

Evans-Pritchard, Sir E(dward) E(van) (b. Sept. 21, 1902, Crow- borough, Sussex, Eng.—d. Sept. 11, 1973, Oxford, Oxfordshire) British social anthropologist. The most influential British social anthropologist since Bronisiaw Malinowski and A.R. Radcliffe-Brown, Evans-Pritchard succeeded the latter at Oxford University (1946), where he served as mentor to a generation of students. His studies of African systems of belief, witchcraft, religion, politics, and oral tradition remain foundational to the study of African societies and non-Western systems of thought. Among his major works are Witchcraft, Oracles and Magic Among the Azande (1937), The Nuer (1940), and (with Meyer Fortes) African Politi¬ cal Systems (1940).

Evansville City (pop., 2000: 121,582), southwestern Indiana, U.S. A port on the Ohio River, it was founded in 1812 and grew as the southern terminus of the Wabash and Erie Canal (1853), which connected Lake Erie with the Ohio River. Coal deposits and oil fields as well as fertile farmlands surround the city, and its location as a transportation hub has made it the metropolis of southwestern Indiana and adjacent states. Diver¬ sified manufactures include pharmaceuticals and refrigeration and air con¬ ditioning equipment. It is the seat of the University of Evansville (1854). Angel Mounds State Memorial, a large archaeological site, is nearby.

evaporation Change of a liquid into the gaseous state; in particular, the process by which liquid water enters the atmosphere as water vapour. Evaporation, mostly from the sea and from vegetation, replenishes the humidity of the air. It is an important part of the exchange of energy in the Earth-atmosphere system that produces atmospheric motion, and therefore weather and climate. The rate of evaporation depends on the temperature difference between the evaporating surface and the air, the relative humidity, and wind.

evaporator Industrial apparatus for converting liquid into gas or vapour. The single-effect evaporator consists of a container or surface and a heating unit; the multiple-effect evaporator uses the vapour produced in one unit to heat a succeeding unit. Double-, triple-, or quadruple-effect evaporators may be used in industrial and steam heating plants. Some evaporators are used to concentrate a solution by vaporizing and elimi¬ nating water (e.g., in a concentration plant for sugar and syrup). In puri¬ fication processes such as desalination, evaporators convert the water to vapour, leaving mineral residues behind; the vapour is then condensed into (desalinated) water. In a refrigeration system, the cooling is produced as the rapid evaporation of the liquid refrigerant absorbs heat.

evaporite \i-'va-p3-,rlt\ Any of a variety of minerals found in sedimen¬ tary deposits of soluble salts that result from the evaporation of water. Typically, evaporite deposits occur in closed marine basins where evapo¬ ration exceeds inflow. The most important such minerals include anhy¬ drite, halite, calcite, gypsum, polyhalite, and potassium and magnesium salts such as sylvite, carnallite, kainite, and kieserite.

evapotranspiration Loss of water from the soil both by evaporation from the soil surface and by transpiration from the leaves of the plants growing on it. Factors that affect the rate of evapotranspiration include

Dame Edith Evans as Mrs. Ross in The Whisperers, 1967.

COURTESY OF SEVEN PINES PRODUCTIONS LTD.; PHOTOGRAPH, PICTORIAL PARADE

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Evarts ► evolution I 647

the amount of solar radiation, atmospheric vapor pressure, temperature, wind, and soil moisture. Evapotranspiration accounts for most of the water lost from the soil during the growth of a crop. Estimation of evapotrans¬ piration rates is thus important in planning irrigation schemes.

Evarts \'e-vorts\, William Maxwell (b. Feb. 6, 1818, Boston, Mass., U.S.—d. Feb. 28, 1901, New York, N.Y.) U.S. lawyer. He served as coun¬ sel for Pres. Andrew Johnson in his impeachment trial (1868). After Johnson’s acquittal, he served as U.S. attorney general (1868-69), then represented the U.S. in the Alabama claims arbitration at Geneva (1872). He was Republican chief counsel in the election dispute between Ruth¬ erford B. Hayes and Samuel Tilden in 1876. As Hayes’s secretary of state (1877-81), he asserted U.S. interests over a proposed canal in Panama. He later served in the U.S. Senate (1885-91).

Evelyn Vev-tan, 'ev-lonV, John (b. Oct. 31, 1620, Wotton, Surrey, Eng.—d. Feb. 27, 1706, Wotton) British writer. A country gentleman from a wealthy landowning family, he wrote some 30 books on the fine arts, forestry, and religious topics. His Diary (published 1818), which he kept from 1631 to 1706, is an invaluable source of information on 17th-century social, cultural, religious, and political life. His Life of Mrs. Godolphin (published 1847) is one of the most moving of 17th-century biographies.

evening grosbeak North American grosbeak ( Hesperiphona vesper- tina) that is brown, yellow, black, and white. Like all other grosbeaks, it has a large conical bill. It eats seeds and tends to form loose flocks in flight.

evening primrose Any of various species of herbaceous plants of the genus Oenothera (family Onagraceae). They are noted for their showy flowers, especially the yellow-flowered biennial O. biennis, which is found widely throughout North America and and has been introduced to Europe. It has been grown by geneticists to determine certain principles of heredity. The true primrose belongs to the family Primulaceae.

Evenk See Siberian peoples

event horizon Boundary marking the limits of a black hole. At the event horizon, the escape velocity is equal to the speed of light. Since general relativity states that nothing can travel faster than the speed of light, noth¬ ing inside the event horizon can ever cross the boundary and escape beyond it, including light. Thus, nothing that enters a black hole can get out or can be observed from outside the event horizon. Likewise, any radiation generated inside the horizon can never escape beyond it. For a nonrotating black hole, the Schwarzschild radius delimits a spherical event horizon. Rotating black holes have distorted, nonspherical event horizons. Since the event horizon is not a material surface but rather merely a math¬ ematically defined demarcation boundary, nothing prevents matter or radiation from entering a black hole, only from exiting one. Though black holes themselves may not radiate energy, electromagnetic radiation and matter particles may be radiated from just outside the event horizon via Hawking radiation.

Everest, Mount Tibetan Chomolungma \,cho-m6-Tur]-m3\ Nepali Sagarmatha Peak on the crest of the Himalayas, southern Asia. The highest point on Earth, with a summit at 29,035 ft (8,850 m), it lies on the border between Nepal and Tibet (China). Numerous attempts to climb Everest were made from 1921; the summit was finally reached by Edmund Hillary of New Zealand and Tenzing Norgay of Nepal in 1953. In dispute is whether the English explorer George Mallory, whose body was dis¬ covered below Everest’s peak in 1999, had actually reached the peak ear¬ lier, in 1924, and was descending it when he died. The formerly accepted elevation of 29,028 ft (8,848 m), established in the early 1950s, was recalculated in the late 1990s.

Everglades Subtropical saw-grass marsh region, southern Florida, U.S. Covering about 4,000 sq mi (10,000 sq km), the area has water moving slowly through it from the lip of Lake Okeechobee to mangrove swamps bordering the Gulf of Mexico and Florida Bay. Everglades National Park, established in 1934, encompasses the southwestern portion of the marsh, covering 2,354 sq mi (6,097 sq km). The largest subtropical wilderness left in the continental U.S., it has a mild climate, which provides an envi¬ ronment for myriad birds, alligators, snakes, and turtles. A large portion of the glades has been reclaimed by drainage canals, altering the habitats of many species.

evergreen Any plant that retains its leaves through the winter and into the following summer or through several years. Many tropical species of

broad-leaved flowering plants are evergreen, but in cold-temperate and Arctic areas the evergreens commonly are cone-bearing shrubs or trees (conifers), such as pines and firs. The leaves of evergreens usually are thicker and more leathery than those of deciduous trees and often are needlelike or scalelike in cone-bearing trees. A leaf (or needle) may remain on an evergreen tree for two years or longer and may fall during any season.

everlasting Any of several plants that retain their form and colour when dried and are used in dry bouquets and flower arrangements. Popu¬ lar everlastings include several species of the composite family, especially the true everlastings, or immortelles, species of the genus Helichrysum, native to North Africa, Crete, and the parts of Asia bordering on the Mediterranean and cultivated in many parts of Europe. One of the best- known everlastings is the strawflower ( H. bracteatum ) of Australia. Many GRASSes with showy plumes or spikes are classified as everlastings.

ever-normal granaries Price-stabilizing granaries first established in the 1st century bc. Under the Qing dynasty they were set up by all Chi¬ nese provinces in each county to keep grain on hand to offset regional food shortages in years of crop failure. By keeping the supply of grain stable (“ever normal”), the granaries stabilized prices, and even undevel¬ oped regions of the country were protected from famine.

Evers Ve-verzV Med gar (Wiley) (b. July 2, 1925, Decatur, Miss., U.S.—d. June 12, 1963, Philadelphia, Miss.) African American civil- rights activist. After serving in World War II he entered business in Mis¬ sissippi. He and his elder brother, Charles, began organizing local affiliates of the NAACP; in 1954 Medgar became the organization’s first field sec¬ retary in Mississippi. He traveled throughout the state recruiting members and organizing economic boycotts. In June 1963, hours after a speech on civil rights by Pres. John F. Kennedy, Evers was shot and killed in an ambush outside his home. A white segregationist was charged with the murder but was set free after two trials in 1964 resulted in hung juries; he was finally convicted after a third trial in 1994. Evers’s widow, Myr- lie Evers-Williams, later headed the NAACP (1995-98).

Evert, Chris(tine Marie) formerly Chris Evert Lloyd (b. Dec. 21, 1954, Fort Lauderdale, Fla., U.S.) U.S. tennis player. She became in 1971 the youngest player to reach the semifinals of the U.S. championship. She won the U.S. Open women’s singles six times (1975-78, 1980, 1982) and repeatedly won the Wimbledon singles (1974, 1976, 1981), the French Open singles (1974, 1975, 1979, 1980, 1983, 1985, 1986), and the Aus¬ tralian Open singles (1982, 1984), for a total of 18 grand-slam titles. She retired in 1989.

evidence In law, something (e.g., testimony, documents, or physical objects) presented at a judicial or administrative proceeding for the pur¬ pose of establishing the truth or falsity of an allegation of fact. To pre¬ serve legal due process and to prevent the jury from being misled, an extensive body of rules has sprung up regarding the handling of evidence. In the U.S., all federal and many state courts adhere to the Federal Rules of Evidence, which covers such elements as types of evidence, admissi¬ bility, relevance, competency of witnesses, confessions and admissions, expert testimony, and authentication. Most evidence received at trial is in the form of verbal statements of witnesses, who are subject to question¬ ing by attorneys from both sides. Two important categories of evidence are direct evidence, which is offered by a witness whose knowledge of a factual matter is firsthand (as through sight or hearing), and circumstan¬ tial evidence. See also exclusionary rule.

evil eye Superstition holding that a glance can cause injury or death to those on whom it falls. The belief was found in ancient Greece and Rome as well as in folk cultures around the world, and it has persisted into mod¬ ern times. Children and animals are believed to be particularly vulner¬ able. The evil eye is often thought to stem from envy and malice toward prosperity and beauty, and thus in many cultures unguarded praise of one’s possessions or children is thought to invite misfortune. Safeguards include amulets, charms, and sacred texts; in Asia children may have their faces blackened for protection.

Evita See Eva Peron

evolution Biological theory that animals and plants have their origin in other preexisting types and that the distinguishable differences are due to modifications in successive generations. It is one of the keystones of modern biological theory. In 1858 Charles Darwin and Alfred Russel Wal¬ lace jointly published a paper on evolution. The next year Darwin pre-

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648 I Evripos Strait ► executive

sented his major treatise On the Origin of Species by Means of Natural Selection, which revolutionized all later biological study. The heart of Darwinian evolution is the mechanism of natural selection. Surviving indi¬ viduals, which vary (see variation) in some way that enables them to live longer and reproduce, pass on their advantage to succeeding generations. In 1937 Theodosius Dobzhansky applied Mendelian genetics (see Gregor Mendel) to Darwinian theory, contributing to a new understanding of evo¬ lution as the cumulative action of natural selection on small genetic varia¬ tions in whole populations. Part of the proof of evolution is in the fossil record, which shows a succession of gradually changing forms leading up to those known today. Structural similarities and similarities in embry¬ onic development among living forms also point to common ancestry. Molecular biology (especially the study of genes and proteins) provides the most detailed evidence of evolutionary change. Though the theory of evolution is accepted by nearly the entire scientific community, it has sparked much controversy from Darwin’s time to the present; many of the objections have come from religious leaders and thinkers (see cre¬ ationism) who believe that elements of the theory conflict with literal interpretations of the Bible. See also Hugo de Vries, Ernst Haeckel, human evolution, Ernst Mayr, parallel evolution, phylogeny, sociocultural evolution,

SPECIATION.

Evripos Strait See Euripus Strait

Ewald Va-vohA, Johannes (b. Nov. 18, 1743, Copenhagen, Den.—d. March 17, 1781, Copenhagen) Danish poet and dramatist. By age 19 he was becoming known as a writer. At 30, addicted to alcohol, he adopted a more solitary life and began producing his mature works, including The Death of Balder (1774), in which he became the first Danish poet to use themes from Scandinavian myth and saga. Of his dramatic works, only the operetta Fiskerne (1779; “The Fishermen”) is still performed. He is espe¬ cially known for his great personal odes and for songs such as “King Christian Stood by the Lofty Mast,” used as a national anthem, and “Lille Gunver,” the first Danish romance. He is considered one of Denmark’s greatest lyric poets. His memoirs (published 1804) are his greatest prose work.

Ewe \'a-wa\ Peoples of southeastern Ghana, southern Benin, and south¬ ern Togo. They speak dialects of Gbe, a Kwa language of the Niger-Congo family. The Ewe never formed a single centralized state, remaining a col¬ lection of independent communities that made temporary alliances in time of war. Most Ewe are farmers; some coastal Ewe fish. Spinning, weav¬ ing, pottery making, and blacksmithing are important crafts. They num¬ ber more than 3.5 million.

Ewing Vyii-iqV (William) Maurice (b. May 12, 1906, Lockney, Texas, U.S.—d. May 4, 1974, Galveston, Texas) U.S. geophysicist. He taught many years at Columbia University (1944-74) and also directed the Lamont-Doherty Geological Observatory (1949-74). Studying the structure of the Earth’s crust and mantle, he made seismic refraction mea¬ surements in the Atlantic basins, along the Mid-Atlantic Ridge, and in the Mediterranean and Norwegian seas. In 1935 he took the first seismic measurements in open seas. He was among those who proposed that earthquakes are associated with the central oceanic rifts that encircle the globe, suggesting that seafloor spreading may be worldwide and episodic in nature. In 1939 he took the first deep-sea photographs.

excavation In archaeology, the exposure, recording, and recovery of buried material remains. The techniques employed vary by the type of site, but all forms of archaeological excavation require great skill and careful preparation. The process begins with site location, by means of aerial photography, remote sensing, or, commonly, accidental discovery by construction crews. This step is followed by surveying and mapping, site sampling, and developing an excavation plan. The design and execu¬ tion of an excavation frequently require an interdisciplinary team of experts. The actual digging consists of the removal of surplus dirt and the painstaking examination, through observation, sifting, and other means, of remaining soil, artifacts, and context. Common dig tools include the trowel, penknife, and brush. The excavation phase is followed by artifact classification, analysis, dating, and the publication of results. Excavation may last decades or be a short-term emergency salvage operation (as when a site is threatened by development).

exchange, bill of See bill of exchange

exchange control Governmental restrictions on private transactions in foreign money or claims on foreign money. Residents are required to

sell foreign money coming into their possession to a central bank or spe¬ cialized government agency at exchange rates set by the government. The chief function of most systems of exchange control is to maintain a favour¬ able BALANCE OF PAYMENTS. See also FOREIGN EXCHANGE.

exchange rate Price of one country’s money in relation to another’s. Exchange rates may be fixed or flexible. An exchange rate is fixed when two countries agree to maintain a fixed rate through the use of monetary policy. Historically, the most famous fixed exchange-rate system was the gold standard; in the late 1850s, one ounce of gold was defined as being worth 20 U.S dollars and 4 pounds sterling, resulting in an exchange rate of 5 dollars per pound. An exchange rate is flexible, or “floating,” when two countries agree to let international market forces determine the rate through supply and demand. The rate will fluctuate with a country’s exports and imports. Most world trade currently takes place with flexible exchange rates that fluctuate within relatively fixed limits. See also EXCHANGE CONTROL, FOREIGN EXCHANGE.

Exchequer \iks-'che-kar, 'eks-.che-korV English government department responsible for receiving and dispersing public revenue. It was established by Henry I in the 12th century, and its name refers to the checkered cloth on which the reckoning of revenues took place. Originally, the lower Exchequer was an office for the receipt and payment of money, while the upper Exchequer was a court sitting twice a year to regulate accounts. The English judicial system grew out of the upper Exchequer, and the lower Exchequer became the Treasury. “Exchequer” is still the unofficial name of the Treasury in Britain.

excitation Addition of a discrete amount of energy to a system that changes it usually from a state of lowest energy (ground state) to one of higher energy (excited state). For example, in a hydrogen atom, an exci¬ tation energy of 10.2 electron volts is required to move the lone electron from its ground state to its first excited state. The excitation energy stored in excited atoms and nuclei is usually emitted as ultraviolet radiation from atoms and as gamma radiation (see gamma ray) from nuclei as they return to their ground states.

exclusionary rule In U.S. law, the principle that evidence seized by police in violation of the constitutional protection against unreasonable search and seizure may not be used against a criminal defendant at trial. The Supreme Court of the United States established the validity of the rule in Weeks v. U.S. (1914). In Wolf v. Colorado (1949) the court limited application of the rule to the federal courts; this decision was overturned in Mapp v. Ohio (1961), which required the rule to be applied universally. In the 1980s the court allowed an exception to the rule, holding that evi¬ dence obtained “in good faith” with a search warrant later ruled invalid is admissible.

excommunication Form of censure by which a member of a religious body is excluded from the congregation of believers and from the rites of the church. Excommunication has been used in various religions, nota¬ bly Christianity, as a punishment for grave offenses such as heresy. In Roman Catholicism an excommunicated person is barred from receiving the sacraments and from burial in consecrated ground. The offender may be absolved by a priest (in some cases, only by a bishop or the pope) and received back into the church after confessing his or her sin and doing penance for it. In Protestant denominations other terms, such as “church discipline,” may be attached to essentially the same censure. Although now seldom used, the practice of herein in Judaism was a form of excom¬ munication that excluded people from the community for prescribed times or forbade them from hearing the Torah. The term is also applied to the expulsion of Buddhist monks from the sangha.

excretion Bodily process for disposing of undigested food waste prod¬ ucts and nitrogenous by-products of metabolism, regulating water content, maintaining acid-base balance, and controlling osmotic pressure to pro¬ mote homeostasis. It refers to both urination and defecation and to the pro¬ cesses that take place in the digestive and urinary systems, as the kidney and liver filter wastes, toxins, and drugs from the blood and food reaches the last stage of digestion. Ammonia from protein digestion, the primary excretory product, is converted to urea to be excreted in urine.

executive In politics, a person or persons constituting the branch of government charged with executing or carrying out the laws and appoint¬ ing officials, formulating and instituting foreign policy, and providing diplomatic representation. In the U.S., a system of checks and balances

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exegesis ► Explorer I 649

keeps the power of the executive more or less equal to that of the judi¬ ciary and the legislature. See also mayor, president, prime minister.

exegesis V.ek-so-'je-sos, 'ek-s3-je-sos\ Scholarly interpretation of reli¬ gious texts, using linguistic, historical, and other methods. In Judaism and Christianity, it has been used extensively in the study of the Bible. Textual criticism tries to establish the accuracy of biblical texts. Philological criti¬ cism deals with grammar, vocabulary, and style in pursuit of faithful translation. Literary criticism classifies texts according to style and attempts to establish authorship, date, and audience. Tradition criticism seeks the sources of biblical materials and traces their development. Redaction criticism examines the way pieces of the tradition have been assembled into a literary composition by editors. Form criticism studies the way narratives are shaped by the cultures that produce them. Histori¬ cal criticism looks at a text’s historical context.

Exekias \ek-'sek-yos\ (fl. c. 540-520 bc, Greece) Greek potter. He was the most famous of the black-figure vase painters (see black-figure pot¬ tery). His name is found on 13 surviving vases. He is known for his elegant drawing; his greatest gift was for conveying pathos and insight rather than overt action. Some 40 unsigned vases are attributed to him on stylistic grounds. He also made clay plaques designed to decorate tombs.

exercise Training of the body to improve health and fitness. Different types have different purposes, including aerobics for heart and respiratory function and weight loss, weight-bearing exercise for bone strength, weight training for muscle strength, and stretching for flexibility. Specific exercises are used in physical medicine and rehabilitation. Benefits include lower blood pressure, higher HDL cholesterol, improved disease resistance, and better general well-being.

Exeter \'ek-sa-tar\ ancient Isca Dumnoniorum City and adminis¬ trative district (pop., 2001: 111,078), administrative and historic county of Devon, England. The county town (seat) of Devon, it is located on the River Exe about 10 mi (16 km) above the English Channel and commands an important river crossing. An early British tribe, the Dumnonii, made Exeter their centre; when it was taken by the Romans, they named it Isca Dumnoniorum. The main town in southwestern England during the Middle Ages, Exeter was subjected to a number of sieges. Alfred the Great twice held it against the Danes (877 and c. 894); the Danes finally took the city in 1003 but lost it in 1068 to William I (the Conqueror). Exeter’s Norman cathedral, consecrated in 1133, houses the Exeter Book, the larg¬ est collection extant of Old English poetry. The city has light manufactur¬ ing and is a service centre for an extensive region.

existentialism Philosophical movement oriented toward two major themes, the analysis of human existence and the centrality of human choice. Existentialism’s chief theoretical energies are thus devoted to questions about ontology and decision. It traces its roots to the writings of Soren Kierkegaard and Friedrich Nietzsche. As a philosophy of human existence, existentialism found its best 20th-century exponent in Karl Jas¬ pers; as a philosophy of human decision, its foremost representative was Jean-Paul Sartre. Sartre finds the essence of human existence in freedom—in the duty of self-determination and the freedom of choice— and therefore spends much time describing the human tendency toward “bad faith,” reflected in humanity’s perverse attempts to deny its own responsibility and flee from the truth of its inescapable freedom.

Exmouth Gulf Inlet of the Indian Ocean, Western Australia. Located between North West Cape and the mainland, the gulf is 55 mi (90 km) long and 30 mi (48 km) across the mouth. Fishing, pearling, prawning, and tour¬ ism are the main local industries. Nearby Cape Range National Park is important for the conservation of the rare yellow-footed rock wallaby.

Exodus Second book of the Old Testament. The title refers to the depar¬ ture of the Israelites from Egypt under Moses in the 13th century bc. The book begins with the story of the Israelites’ enslavement in Egypt and God’s call to Moses to become a prophet. It tells of the plagues sent to persuade the pharaoh to free the Israelites, and it recalls their crossing of the Sea of Reeds (or the Red Sea) and their 40 years of wandering in the Sinai desert. It also recounts how God made a covenant with Israel at Mount Sinai, handing down the Ten Commandments. In Exodus God estab¬ lishes his reliability as Israel’s protector and savior, and lays claim to its loyalty and obedience.

exogamy and endogamy \ek-'sa-g3-me...en-'da-g9-me\ Practices controlling the relation of the sexes in the selection of marital partners. Exogamous groups require their members to marry outside the group,

sometimes even specifying the group into which members must marry. Such groups are usually defined in terms of kinship rather than politics or territory. Exogamy is usually characteristic of unilineal descent groups, in which descent is reckoned either patrilineally or matrilineally. In endoga- mous groups, marriage outside one’s group may be forbidden, or there may merely be a tendency to marry within the group. Endogamy is char¬ acteristic of aristocracies and religious and ethnic minorities in industri¬ alized societies but also of the caste system in India and of class-conscious nonliterate societies such as the Masai of East Africa.

exorcism In Christianity, a ceremony used to drive demons out of a per¬ son they have possessed. Jesus healed people tormented by evil spirits, casting them out with a word, and his followers later drove out demons “in his name.” By the 3rd century this task was assigned to a specially trained class of lower clergy. Rituals for exorcism of people and places also exist in many other traditions.

expanding universe Current understanding of the state of the uni¬ verse. It is based on the finding that all galaxies are moving away from each other. Application of general relativity to cosmology, along with the detection of redshifted light coming from galaxies outside the Milky Way Galaxy, led to the realization in the 1920s that all galaxies are receding (see Edwin Hubble). It is unknown whether the universe will expand indefi¬ nitely (open universe) or eventually collapse (closed universe) into an extremely dense, congested state, as it began, according to the big-bang model. See also Friedmann universe.

experimental psychology Branch or type of psychology concerned with employing empirical principles and procedures in the study of psy¬ chological phenomena. The experimental psychologist seeks to carry out tests under controlled conditions in order to discover an unknown effect or law, to examine or establish a hypothesis, or to illustrate a known law. The areas of study that rely most heavily on the experimental method include those of sensation and perception, learning and memory, motivation, and physiological psychology. Experimental approaches are also used in CHILD PSYCHOLOGY, CLINICAL PSYCHOLOGY, EDUCATIONAL PSYCHOLOGY, and SOCIAL PSY¬ CHOLOGY.

experimentalism See instrumentalism

expert system Computer-based system designed to respond like a human expert in a given field. Expert systems are built on knowledge gathered from human experts, analogous to a database but containing rules that may be applied to solving a specific problem. An interface allows the user to specify symptoms and to clarify a problem by responding to ques¬ tions posed by the system. Software tools exist to help designers build a special-purpose expert system with minimal effort. An outgrowth of work in artificial intelligence, expert systems show promise for an ever-widening range of applications. There are now widely used expert systems in the fields of medicine, personnel screening, and education.

explanation In philosophy, set of statements that makes intelligible the existence or occurrence of an object, event, or state of affairs. Among the most common forms of explanation are causal explanation (see cau¬ sation), deductive-nomological explanation (see covering-law model), which involves subsuming the explanandum under a generalization from which it may be derived in a deductive argument (e.g., “All gases expand when heated; this gas was heated; therefore, this gas expanded”) and sta¬ tistical explanation, which involves subsuming the explanandum under a generalization that gives it inductive support (e.g., “Most people who use tobacco contract cancer; this person used tobacco; therefore, this person contracted cancer”). Explanations of human behaviour typically appeal to the subject’s beliefs and desires, as well as other facts about him, and proceed on the assumption that the behaviour in question is rational (at least to a minimum degree). Thus an explanation of why the subject removed his coat might cite the fact that the subject felt hot, that the sub¬ ject desired to feel cooler, and that the subject believed that he would feel cooler if he took off his coat.

Explorer Any of the largest (55-member) series of unmanned U.S. spacecraft, launched between 1958 and 1975. Explorer 1, the first satellite sent into orbit by the U.S., discovered the innermost Van Allen radiation belt. Other notable craft in this series include Explorer 38 (1968), which measured galactic radio sources and studied low radio frequencies in space, and Explorer 53 (SAS 3; 1975), which investigated X-ray and gamma-ray sources within and beyond the Milky Way Galaxy. See photo on following page.

© 2006 Encyclopaedia Britannica, Inc.

650 i explosive ► extrusion

Explorer 10 satellite undergoing testing in a NASA laboratory prior to being launched in 1961.

NASA

explosive Any substance or device that can produce a volume of rap¬ idly expanding GAS in an extremely brief period. Mechanical explosives, which depend on a physical reaction (e.g., overloading a container with compressed air until it bursts), are little used except in mining. Nuclear explosives (see nuclear weapon) use either nuclear fission or nuclear fusion. Chemical explosives are of two types: detonating (high) explosives (e.g., TNT, dynamite) have extremely rapid decomposition and development of high pressure; deflagrating (low) explosives (e.g., black powder, smoke¬ less powder; see gunpowder) merely burn quickly and produce relatively low pressure. Primary detonating explosives are ignited by a flame, a spark, or an impact; secondary ones require a detonator and sometimes a booster. Modern high explosives use either mixtures of ammonium nitrate and fuel oil or ammonium nitrate-based water gels.

exponential function In mathematics, a function in which a constant base is raised to a variable power. Exponential functions are used to model changes in population size, in the spread of diseases, and in the growth of investments. They can also accurately predict types of decline typified by radioactive decay (see half-life). The essence of exponential growth, and a characteristic of all exponential growth functions, is that they double in size over regular intervals. The most important exponential function is e x , the inverse of the natural logarithmic function (see logarithm).

Export-Import Bank of the United States (Ex-lm Bank) One

of the principal U.S. government agencies in international finance. Origi¬ nally incorporated as the Export-Import Bank of Washington in 1934, its goal is to help finance U.S. exports, principally by lending money to for¬ eign buyers of U.S. goods and services. Such assistance often consists of credits to foreign banks and governments in connection with development projects. See also development bank.

Expressionism In the visual arts, artistic style in which the artist depicts not objective reality but the subjective emotions that objects or events arouse. This aim is accomplished through the distortion and exag¬ geration of shape and the vivid or violent application of colour. Its roots are found in the works of Vincent van Gogh, Edvard Munch, and James Ensor. In 1905 the movement took hold with a group of German artists known as Die Brucke; their works influenced such artists as Georges Rouault, Chaim Soutine, Max Beckmann, Kathe Kollwitz, and Ernst Barlach. The group of artists known as Der Blaue Reiter were also considered Expressionists. Expressionism was the dominant style in Germany after World War I; postwar Expressionists included George Grosz and Otto Dix. Its emotional qualities were adopted by other 20th-century art move¬ ments. See also Abstract Expressionism.

extenuating circumstance or mitigating circumstance In

law, circumstance that diminishes the culpability of one who has com¬ mitted a criminal offense. In many Anglo-American legal systems, provo¬ cation of the accused by the victim can reduce a charge of first-degree murder to second-degree murder or to manslaughter. In Britain, a charge

of murder may be reduced to manslaughter if the accused is found to be suffering diminished capacity (see diminished responsibility). The Italian penal code allows consideration of motives of honour. Extenuating cir¬ cumstances also are a factor in many civil actions.

extinction (of species) Dying out or termination of a species. It occurs when a species can no longer reproduce at replacement levels. Most past extinctions are thought to have resulted from environmental changes that the doomed species was either unable to adapt to or that caused it to adapt so thoroughly that it became a distinctly new species. The effect of humans on the environment, through hunting, collecting, and habitat destruction, has become the principal factor in plant and ani¬ mal extinctions.

extortion Unlawful exaction of money or property through intimida¬ tion or undue exercise of authority. It may include threats of physical harm, criminal prosecution, or public exposure. Some forms of threat, especially those made in writing, are occasionally singled out for sepa¬ rate statutory treatment as blackmail. See also bribery.

extradition Process by which one state, at the request of another, returns a person for trial for a crime punishable by the laws of the request¬ ing state and committed outside the state of refuge. Extradition is regu¬ lated within countries by extradition acts and between countries by treaties. Some principles of extradition are common to many countries. Most decline to surrender their own nationals. Countries also generally recognize the right of political asylum. In view of the solidarity of nations in the repression of crime, however, countries are usually willing to coop¬ erate in bringing criminals to justice.

extrasensory perception (ESP) Perception that involves awareness of information about something (such as a person or event) not gained through the senses and not deducible from previous experience. Classic forms of ESP include telepathy, clairvoyance, and precognition. No con¬ clusive demonstrations of the existence of ESP in any individual have been given, but popular belief in the phenomenon remains widespread, and people who claim to possess ESP are sometimes employed by inves¬ tigative teams searching for missing persons or things. See also parapsy¬ chology.

extrasolar planets See planets of other stars extrovert See introvert and extravert

Extremadura or Estremadura \es-,tra-m3- , thu-ra,\ Portuguese \ l ish-tri-m9-'dur-9\ Historical region and autonomous community (pop., 2001: 1,058,503), west-central Spain. Covering an area of 16,075 sq mi (41,634 sq km), it encompasses the southwestern provinces of Caceres and Badajoz. Its capital is Merida. During the Christian reconquest of the Iberian Peninsula, the name Extremadura was used to refer to the zones outside of Moorish territory. From the late Middle Ages the term was applied to an area approximating the modern region. The countryside remains partitioned into latifundios (large estates); wheat, grapes, and olives are important crops.

extreme sports Sports events characterized by high speed or high risk. Such sports include aggressive inline skating, wakeboarding, street luge, skateboarding, and freestyle bicycle events (wherein tricks such as back flips are performed on a bicycle). Many of the events—snowboarding, skateboarding, and freestyle biking are examples—are performed on ramps and inclines or in a halfpipe, some with walls as high as 50 feet, which allows the athletes to get air, or achieve the height necessary to, for example, rotate on a bicycle. Many of these sports were made popu¬ lar’ by the X Games (championship competitions sponsored by the cable- television network ESPN). The 1998 and 2002 Olympic Games featured extreme snowboarding events in a halfpipe, in which boarders performed jumps, rotations, and mid-air maneuvers.

extrusion Process in which metal or other material is forced through a series of dies to create desired shapes. Many ceramics are manufactured by extrusion, because the process allows efficient, continuous production. In a commercial screw-type extruder, a screw auger continuously forces the plastic feed material through an orifice or die, resulting in simple shapes such as cylindrical rods and pipes, rectangular solid and hollow bars, and long plates. In metalworking, extrusion converts a billet of metal into a length of uniform cross-section by forcing the billet through the orifice of a die; aluminum is easily extruded. Formed sheet aluminum is used for opaque curtain-wall panels and window frames.

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extrusive rock ► Ezra I 651

extrusive rock Any igneous rock derived from magma that is poured out or ejected at the Earth’s surface. Extrusive rocks are usually distin¬ guished from intrusive rocks on the basis of their texture and mineral com¬ position. Lava flows and pyroclastic debris (fragmented volcanic material) are extrusive; they are commonly glassy (e.g., obsidian) or finely crystal¬ line (e.g., basalts and felsites).

Exupery, Antoine de Saint- See Antoine de Saint-Exupery

Exxon Mobil Corporation U.S.-based oil and gas company formed in 1999 through the merger of Exxon Corp. and Mobil Corp. It has invest¬ ments and operations in petroleum and natural gas, coal, nuclear fuels, chemicals, and ores. It also operates pipelines and one of the world’s largest fleets of tankers. Exxon Mobil engages in every phase of the petroleum industry from oil fields to service stations. Both Exxon and Mobil had their origins in Standard Oil (see Standard Oil Co. and Trust) and were founded in the late 1800s. In 1926 the New Jersey subsidiary of Standard Oil, Exxon’s predecessor, introduced the Esso brand name. The name was changed to Exxon in 1972. As of 2002 Exxon Mobil was the world’s largest integrated oil company.

Eyasi \a-'ya-se. Lake Lake, northern Tanzania. At an elevation of about 3,400 ft (1,040 m), the lake covers an area of about 400 sq mi (1,050 sq km) and occupies the bottom of a bowl-like depression. Its walls are purple lava, enclosing a broad expanse of white alkaline shallows. Flamingos inhabit the lakeshore in vast flocks. Hominid fossils were found nearby.

Eybeschutz \1-ba- I shffits\ # Jonathan (b. c. 1690, Krakow, Pol.—d. 1764, Altona, Den.) Polish rabbi and Talmudic scholar. He served as rabbi in a number of European towns, and his scholarship gained him a loyal following. He was reputed to have mystic powers; when the women of his congregation asked him to give them protection from death in child¬ birth, he offered them amulets that contained a prayer to the false mes- siah Shabbetai Tzevi. A prominent German rabbi, Jacob Emden (1697- 1776), denounced the amulets. The dispute that ensued between Emden and Eybeschutz divided the European Jewish community.

Eyck \'ik\, Jan van (b. before 1395, Maaseik, Bishopric of Liege, Holy Roman Empire—d. before July 9, 1441, Bruges) Flemish painter. He is recorded in 1422 as a master painter working for John of Bavaria, count of Holland, and later was employed by Philip III the Good, duke of Burgundy. Securely attributed paintings survive only from the last decade of his career; 10 are signed and dated, an unusually large number for the period. He produced portraits and religious subjects that are unmatched for their technical brilliance, their intellectual complexity, and the richness of their symbolism; he perfected the newly developed technique of oil painting. His masterpiece is the Adoration of the Lamb (1432), known as the Ghent Altarpiece, which he painted with his brother Hubert (c. 1370-1426). He is commonly regarded as the greatest northern European artist of the 15th century. His works were widely copied and avidly collected.

eye Organ that receives light and visual images. Non-image forming, or direction, eyes are found among worms, mollusks, cnidarians, echino- derms, and other invertebrates; image-forming eyes are found in certain mollusks, most arthropods, and nearly all vertebrates. Arthropods are unique in possessing a compound eye, which results in their seeing a multiple image that is partially integrated in the brain. Lower vertebrates such as fish have eyes on either side of the head, allowing a maximum view of the surroundings but producing two separate fields of vision. In predatory birds and mammals, binocular vision became more important. Evolutionary changes in the placement of the eyes permitted a larger overlap of the two visual fields, resulting in the higher mammals in a par¬ allel line of direct sight. The human eye is roughly spherical. Light passes through its transparent front and stimulates receptor cells on the retina (cones for colour vision, rods for black-and-white vision in faint light), which in turn send impulses through the optic nerve to the brain. Vision disorders include near- and farsightedness and astigmatism (correctable with eyeglasses or CONTACT LENSes), colour blindness, and night blindness. Other eye disorders (including detached retina and glaucoma) can cause VISUAL-FIELD DEFECTS Or BLINDNESS. See also OPHTHALMOLOGY; PHOTORECEPTION. See illustration opposite.

eyeglasses Lenses set in frames to wear in front of the eyes to aid vision or correct vision defects (see ophthalmology, optometry). Their use for far¬ sightedness and nearsightedness has been known since the late Middle Ages. In 1784 Benjamin Franklin invented bifocals, with divided lenses for

distant and near vision. Eyeglasses can also correct astigmatism. Most lenses are made of glass or plastic (lighter and more shatterproof than glass but easily scratched). Sunglass lenses are tinted to reduce glare and often treated to reduce ultraviolet light exposure. See also contact lens.

Eyre Peninsula Large promontory, South Australia. Projecting into the Indian Ocean, the peninsula is about 200 mi (320 km) long and lies between the Great Australian Bight and Spencer Gulf. Wheat, sheep, and barley are raised there; iron is extracted in the Middleback Ranges to the northeast. There are numerous resort and fishing towns along the coasts.

Eyre Var\, Lake Salt lake, northeastern South Australia. With a total area of 3,700 sq mi (9,600 sq km), Lake Eyre is the lowest point in Australia, 50 ft (15 m) below sea level. The lake consists of two sections: Lake Eyre North, 90 mi (144 km) long and 40 mi (65 km) wide, is joined by the narrow Goyder Channel to Lake Eyre South, which is 40 mi (65 km) long and about 15 mi (24 km) wide. Lake Eyre is normally dry, and it fills completely only (on average) twice a century. When filled, the lake takes about two years to dry up again. The region is within Lake Eyre National Park.

Ezekiel \i-'zek-yal\ (fl. 6th century bc) Priest and prophet of ancient Israel. He was the subject and partial author of the biblical book of Ezek¬ iel. He began to prophesy to the Jews in Palestine c. 592 bc, pronounc¬ ing God’s judgment on a sinful nation. He witnessed the conquest of Jerusalem by Babylon and saw his fellow Israelites taken away into cap¬ tivity. He offered a promise of Israel’s restoration in his famous vision of a valley of dry bones that revive and assemble themselves. He envisaged a theocratic community revolving around a restored Temple in Jerusalem.

Ezhov, Nikolay See Nikolay Yezhov

Ezra (fl. 4th century bc, Babylon and Jerusalem) Jewish religious leader and reformer. He restored the Jewish community after its exile in Baby¬ lon, persuading the people of Judah to return to a strict observance of Mosaic law. He served as a commissioner of the Persian government, which was tolerant of other religions but required order and authority. His efforts led to a restoration of traditional worship in the rebuilt Temple of Jerusalem and the dissolution of all mixed marriages. For creating a Jew¬ ish community based on the Law, which could exist without political statehood, he is often considered the founder of modern Judaism. His story is told in the books of Ezra and Nehemiah.

medial rectus muscle

retinal blood vessels

posterior

chamber

cornea pupil lens

macula lutea

chamber

iris-

conjunctiva

lateral rectus

retina

-choroid

-sclera

vitreous humour (vitreous body)

Structure of the human eye. The outer portion consists of the white protective sclera and transparent cornea, through which light enters. The middle layer includes the blood-supplying choroid and pigmented iris. Light passing into the interior through the pupil is regulated by muscles that control the pupil's size. The retina comprises the third layer and contains receptor cells (rods and cones) that transform light waves into nervous impulses. The lens, lying directly behind the iris, focuses light onto the retina. The macula lutea, in the centre of the retina, is a region of high visual acuity and colour discrimination. Nerve fibres pass out through the optic nerve to the brain's visual centre. The eye's anterior and posterior chambers con¬ tain a watery fluid that nourishes the cornea and lens. The vitreous humour helps maintain the eye's shape. A thin layer of mucous membrane (conjunctiva) protects the eye's exposed surface. External muscles, including the medial rectus and lateral rectus muscles, connect and move the eye in its socket.

© MERRIAM-WEBSTER INC.

© 2006 Encyclopaedia Britannica, Inc.

652 I F-15 ► fact-value distinction

F-15 or Eagle Twin-engine jet fighter built by the Boeing Company. F-15s were delivered to the U.S. Air Force beginning in 1974 and have been sold to U.S. allies in the Middle East. The F-15 is powered by two turbofan engines that can accelerate it to more than twice the speed of sound. The single-seat F-15 is armed with a 20-mm rotary cannon and an array of short-range and medium-range air-to-air missiles. The fighter- bomber version, known as the Strike Eagle, includes a second seat for the weapons officer, who controls the delivery of missiles and bombs. It car¬ ried out much of the nighttime precision bombing of Iraqi installations in the Persian Gulf War.

F-l 6 or Fighting Falcon Single-seat, single-engine jet fighter built by Lockheed Martin Corp. The first model was delivered to the U.S. Air Force in 1978; it has since been sold to more than a dozen other countries. Produced to fill the need for a lightweight, cost-effective fighter, it is 49 ft (15 m) long and has a wingspan of 31 ft (9.5 m). It can accel¬ erate to more than twice the speed of sound, and its weap¬ onry includes a 20-mm rotary cannon and attachments under the wings and fuselage for a variety of bombs and missiles.

F-86 also called Sabre Vsa-bsrX Early U.S. jet fighter manufactured by North American Aviation, Inc. Built with wings swept back to limit transonic drag as flight speed approached the sound barrier, it could exceed the speed of sound in a dive. The first squadron became operational in 1949, and the fighter saw combat in the Korean War. Pro¬ duction ended in 1956. A single-seat, single-engine fighter, the F-86 was powered by a series of turbojet engines, reaching a top speed of almost 700 mph (1,100 kph) in level flight. It carried guided missiles, machine guns or cannon in the fuselage, and rockets or bombs under the wings.

Fa-hsien See Faxian

Faber Vfa-borV Lothar von (b. June 12, 1817, Stein, Bavaria—d. July 26,1896, Stein) German manufacturer of writing products and art supplies. He took over the family pencil business in Bavaria and transformed it into a worldwide firm, establishing branches throughout Europe and the U.S. and contracting in 1856 for exclusive control of all graphite being mined in Siberia. His brother John Eberhard Faber (1822-79) settled in the U.S. in 1849 and built a large Faber manufacturing plant. The Eberhard Faber Pen¬ cil Co. was incorporated in the U.S. in 1898, and in the same year the Ger¬ man company was renamed Faber-Castell. The contemporary company, Faber-Castell AG, manufactures pens, pencils, and art supplies.