Britannica Concise 2005 - читать бесплатно онлайн полную версию книги автора Encyclopedia Britannica (ч. 108)

1608 i reparations ► Republican Party

genera are Orthoreovirus, Orbivirus, Rotavirus, and Phytoreovirus. The first three infect animals; the last can destroy rice, corn, and other crops.

reparations Payment in money or materials by a nation defeated in war. After World War I, reparations to the Allied Powers were required of Germany by the Treaty of Versailles. The original amount of $33 billion was later reduced by the Dawes Plan and the Young Plan and was can¬ celed after 1933. In the 1920s German resentment over reparations was used by ultranationalists to foment political unrest.

repertory theatre Production of several different plays in a single season by a resident acting company. The plays chosen may be classic works by famous dramatists or new works by emerging playwrights, and the companies that perform them often serve as a training ground for young actors. In Britain the practice, intended to make high-quality the¬ atre available throughout the country, began in the early 20th century. Repertory companies, or stock companies, originally presented a differ¬ ent play each night of the week while preparing and rehearsing new plays. The system evolved to the current practice of presenting a series of short, continuous runs of each play.

Repin \'rya-pyin,\ English \'ra-pin\, Ilya (Yefimovich) (b. Aug. 5, 1844, Chuguyev, Russia—d. Sept. 29, 1930, Kuokkala, Fin.) Russian painter. After training with a provincial icon painter and at the St. Peters¬ burg Academy of Fine Arts, he visited France and Italy on an academy scholarship. On his return he began painting subjects from Russian his¬ tory. In 1873 he achieved international fame with Volga Boatmen, a grim, powerful image that became the model for Soviet Socialist Realism. Among his best-known works is Ivan the Terrible and His Son Ivan (1895), depict¬ ing Ivan’s murder of his son. He also painted vigorous portraits (includ¬ ing Leo Tolstoy and Modest Mussorgsky). In 1894 he became professor of historical painting at the St. Petersburg Academy.

replacement deposit In geology, a mineral deposit formed by chemi¬ cal processes that dissolve the original rock and deposit a new assem¬ blage of minerals in its place. See also metasomatic replacement.

representation In politics, a method or process of enabling a con¬ stituency to influence legislation and government policy through deputies chosen by it. The rationale of representative government is that in large modern countries the people cannot all assemble, as they did in the mar¬ ketplace of democratic Athens. If the public is to participate in govern¬ ment, citizens must select a small number from among themselves to act for them. Political parties have come to act as intermediaries between citizens and their representatives by helping to formulate systematically citizens’ demands. Arguments persist about the proper role of represen¬ tatives; some theories suggest that they should act as delegates carrying out the instructions of the public, whereas others argue that they should serve as free agents, acting in accordance with their best ability and under¬ standing. See also proportional representation.

Representation of the People Acts (1918, 1928) Parliamentary wm acts that expanded suffrage in Britain. The act of 1918 gave the vote to

■ all men over 21 and all women over 30, which tripled the electorate. The

act of 1928 extended the franchise to women aged 21-30. The acts con- wm tinued the voting reforms begun by the Reform Bills (see Reform Bill of

9 1832, Reform Bill of 1867, Reform Bill of 1884-85).

representationalism Theory of knowledge based on the assertion that the mind perceives only mental representations of material objects outside the mind, not the objects themselves. The validity of human knowledge is thus called into question because of the need to show that such images accurately correspond to the external objects. The doctrine, still current in certain philosophical circles, has roots in Cartesianism, the empiricism of John Locke and David Hume, and the idealism of Immanuel Kant.

repression In metabolism, a control mechanism by which a protein molecule, called a repressor, prevents the synthesis of an enzyme by bind¬ ing to (and thus hindering the action of) the DNA that controls the enzyme’s synthesis. Though the process has been studied mainly in micro¬ organisms, it is believed to occur in a similar way in higher organisms. See also inhibition.

repression In psychoanalytic theory, the exclusion of distressing memories, thoughts, or feelings from the conscious mind. Often involv¬ ing sexual or aggressive urges or painful childhood memories, these unwanted mental contents are pushed into the unconscious mind. Repres¬ sion is thought to give rise to anxiety and to neurotic symptoms, which

begin when a forbidden drive or impulse threatens to enter the conscious mind. Psychoanalysis seeks to uncover repressed memories and feelings through free association as well as to examine the repressed wishes released in dreams. See also unconscious.

reproduction Process by which organisms replicate themselves, assur¬ ing continuation of their species. The two basic forms are asexual and sexual. Asexual reproduction (e.g., fission, spore formation, regeneration, and vegetative reproduction) produces an offspring genetically identical to its single parent. Sexual reproduction produces a new individual through the union of special sex cells (gametes), usually from different parents. Gametes result from meiosis. Gamete union results in a zygote, the first cell of a new organism. Sexual reproduction ensures that each offspring is genetically unique (except in cases of multiple offspring derived from divisions of one zygote). Most animals, including all ver¬ tebrates, reproduce sexually.

reproductive behaviour In animals, any activity directed toward perpetuation of a species. Sexual reproduction, the most common mode, occurs when a female’s egg is fertilized by a male’s sperm. The resulting unique combination of genes produces genetic variety that contributes to a species’ adaptability. The stages of approach, identification, and copu¬ lation are well developed to avoid predators and the wastage of eggs and sperm. Most one-celled and some more-complex organisms reproduce asexually. See also courtship behaviour.

reproductive system, human Organ system by which humans reproduce. In females, the ovaries sit near the openings of the fallopian tubes, which carry eggs from the ovaries to the uterus. The cervix extends from the lower end of the uterus into the vagina, whose opening, as well as that of the urethra (see urinary system), is covered by four folds of skin (the labia); the clitoris, a small erectile organ, is located where the labia join in front. The activity of the ovaries and uterus goes through a monthly cycle of changes (see menstruation) throughout the reproductive years except during pregnancy and nursing. In males, the testes lie in a sac of skin (the scrotum). A long duct (the vas deferens) leads from each testis and carries sperm to the ejaculatory ducts in the prostate gland; these join the urethra, which continues through the penis. In the urethra, sperm mixes with secretions from the seminal vesicles, prostate gland, and Cowper gland to form semen. In early embryos, the reproductive systems are unde¬ termined. By birth the organs appropriate to each sex have typically devel¬ oped but are not functioning. They continue to grow, and at puberty their activity increases and maturation occurs, enabling sexual reproduction. See illustration on opposite page.

reptile Any of the approximately 6,000 species of the class Reptilia, air- breathing vertebrates that have internal fertilization and a scaly body and are cold-blooded. Most species have short legs (or none) and have long tails, and most lay eggs. Living reptiles include the scaly reptiles (snakes and lizards; order Squamata), the crocodiles (Crocodilia), the turtles (Che- lonia), and the unique tuatara (Rhynchocephalia). Being cold-blooded, reptiles are not found in very cold regions, and in regions with cold win¬ ters they usually hibernate. They range in size from geckos that measure about 1 in. (3 cm) long to the python, which grows to 30 ft (9 m); the largest turtle, the marine leatherback, weighs about 1,500 lbs (680 kg). Extinct reptiles include the dinosaurs, the pterosaurs, and the dolphinlike ichthyosaurs.

republic Form of government in which a state is ruled by representa¬ tives elected by its populace. The term was originally applied to a form of government in which the leader is periodically appointed under a con¬ stitution; it was contrasted with governments in which leadership is hereditary. A republic may also be distinguished from direct democracy, though modern representative democracies are by and large republics.

Republican, Radical See Radical Republican

Republican Party or GOP (Grand Old Party) One of two major U.S. political parties. It was formed in 1854 by former members of the Whig, Democratic, and Free Soil parties who chose the party’s name to recall the Jeffersonian Republicans’ concern with the national interest above sectional interests and states' rights. The new party opposed slavery and its extension into the territories, as provided by the Kansas-Nebraska Act. Its first presidential candidate, John C. Fremont, won 11 states in 1856; its second, Abraham Lincoln, won the 1860 election by carrying 18 states. Its association with the Union victory in the American Civil War allowed it a long period of dominance nationally, though it was uncom-

Republican Party ► resin I 1609

male

bladder seminal vesicle

ejaculatory

duct

foreskin

(prepuce)

glans penis testis scrotum epididymis

vas

prostate

gland

urethra

penis

Cowper

gland

labia minora labia majora

female

clitoris

urethra

fallopian tube

ovary - fimbria

uterus bladder mons pubis

cervix

vagina

Organs of the human reproductive system. In a male, the scrotum, a pouch of skin, is divided into two sacs, each containing a testis and its associated epididymis. Tubules within the testes contain sperm cells at different stages of development. As sperm leaves the testes, it passes into the epididymis, a highly coiled tube that serves as a reservoir for sperm. The vas deferens, a duct leading out from the epid¬ idymis, joins with the duct of the seminal vesicles as it passes through the prostate gland to form a single tube (ejaculatory duct) that opens into the urethra, the tube that conveys both sperm and urine out through the penis. In a menstruating woman, a follicle containing an egg matures each month in either of two ovaries. Ovulation occurs as the mature follicle ruptures and releases an egg, which is drawn into the ovary's associated fallopian (uterine) tube, which contains a fringe of fingerlike projections (fimbriae). Fertilization usually occurs in the fallopian tube as the egg travels to the uterus. Successful implantation of a fertilized egg in the uterus results in development of an embryo. The vagina, a muscular tube that leads to the uterus, allows sperm to pass into the uterus and serves as a passageway for the fetus during childbirth.

petitive in the South for more than a century after the war. Republican candidates won 14 of 18 presidential elections between 1860 and 1932, through support from an alliance of Northern and Midwestern farmers and big-business interests. In 1912 the party split between a progressive wing led by Theodore Roosevelt and a conservative wing led by Pres. William Howard Taft; the rift enabled the Democratic candidate, Woodrow Wil¬ son, to win that year’s election. The Republican Party’s inability to counter the impact of the Great Depression led to its ouster from power in 1933; in 1953 the presidency of Dwight D. Eisenhower brought a moder¬ ate wing of the party to prominence. The party’s platform remained con¬ servative, emphasizing anticommunism, reduced government regulation

of the economy, and lower taxes; many members also opposed civil rights legislation. In the 1950s the GOP gained new support from middle-class suburbanites and white Southerners disturbed by the integrationist poli¬ cies of the national Democratic Party. Richard Nixon, who narrowly lost the 1960 presidential race, won narrowly in 1968 and by a landslide in 1972, but he was forced to resign in 1974 as a result of the Watergate scandal. Ronald Reagan, who had assumed the leadership of the conser¬ vative wing of the Republican Party after Barry Goldwater’s defeat in the presidential election of 1964, won the presidency in 1980 and 1984; he introduced deep tax cuts and launched a massive buildup of U.S. military forces. Reagan’s vice president, George Bush, was elected in 1988 and enjoyed enormous popularity after success in the First Persian Gulf War, but an anemic economy led to his defeat in 1992 by Democrat Bill Clin¬ ton. The defeat was offset in 1994, when the Republicans regained con¬ trol of the House of Representatives for the first time in 40 years. In 2000 George W. Bush narrowly won the presidency in one of the closest and most controversial elections in U.S. history. In 2004 he won reelection. The party continues to emphasize tax cuts, traditional social values, and strong national defense.

Republican Party, National See National Republican Party

Republican River River, central U.S. Rising in eastern Colorado, it is 422 mi (679 km) long. It flows northeast and east through southern Nebraska, then southeast through northeastern central Kansas to unite with the Smoky Hill River at Junction City and form the Kansas River. It is part of the Missouri River Basin flood-control and land-reclamation project.

requiem mass Musical setting of the mass for the dead. ( Requiem , Latin for “rest,” is the first word of the mass.) The requiem’s text differs from the standard mass Ordinary in omitting its joyous sections and keep¬ ing only the Kyrie, Sanctus, and Agnus Dei, which are combined with other sections, including the sequence Dies irae (“Day of Wrath”). The first surviving polyphonic setting is by Johannes Ockeghem; celebrated later requiems include those of Wolfgang Amadeus Mozart, Hector Ber¬ lioz, Giuseppe Verdi, Gabriel Faure, Johannes Brahms, and Benjamin Britten.

resale price maintenance Measures taken by manufacturers or dis¬ tributors to control the resale prices of their products (i.e., the prices charged by businesses that resell them). Such measures have been applied to a limited array of goods, including pharmaceuticals, books, photo¬ graphic supplies, and liquor. Resale price maintenance first began to be employed in the 1880s, reflecting the success of brand promotion and the resulting increase in competition among retailers. It became especially common in the U.S. but declined after World War II. It is prohibited in some countries. The complexity of marketing channels in industrialized countries makes it increasingly difficult for manufacturers to establish and enforce a single price or even a minimum price for their goods. See also FAIR TRADE LAW.

research and development (R&D) In industry, two closely related processes by which new products and new forms of old products are cre¬ ated through technological innovation. The work generally focuses on two types of research, basic and applied. Basic research is directed toward a generalized goal (e.g., genetic research in a pharmaceutical laboratory). Applied research directs the results of basic research toward the needs of a specific industry and results in the development of new or modified products or processes. In addition to carrying out basic and applied research and developing models, R&D staff may evaluate the efficiency and cost of the product.

resin Vre-z 3 n\ Any natural or synthetic organic compound consisting of a noncrystalline (amorphous) solid or viscous liquid substance or mix¬ ture. Natural resins are usually transparent or translucent yellow to brown and can melt and burn. Most are exuded from trees, especially pines and firs (see conifer), when the bark is injured or stripped. The fluid secretion usually dries out and hardens into a material that can be worked. Natural resins have been used in perfumes and medicines (e.g., balsams), in paints and varnishes (e.g., turpentine and shellac, the latter derived from the secretion of an insect), and in decorative ware (e.g., amber, Oriental lac¬ quer). Synthetic resins are all plastics; the term resin, though still used in the modem industry, dates from the years when synthetics began to replace natural resins. Thermoplastic resins are plastics such as polyeth¬ ylene that can be shaped repeatedly on reheating, whereas thermosetting resins are plastics such as epoxy that set permanently and cannot be reshaped.

1610 I resistance ► Reston

resistance Opposition that a material or electrical circuit offers to the flow of electric current. It is the property of a circuit that transforms elec¬ trical energy into heat energy as it opposes the flow of current. The resis¬ tance R, the electromotive force or voltage V, and the current I are related by Ohm's law. The resistance of an electrical conductor generally increases with increasing temperature and is utilized in devices such as lamps and heaters. The ohm (Q) is the common unit of electrical resis¬ tance; one ohm is equal to one volt (see electromotive force) per ampere.

Resistance or Underground Clandestine groups opposed to Nazi rule in German-occupied Europe in World War II. The groups included civilians who worked secretly against the occupation and armed bands of partisans or guerrilla fighters. Resistance activities ranged from assisting the escape of Jews and Allied airmen shot down over enemy territory to committing sabotage, ambushing German patrols, and sending intelligence information to the Allies. Resistance groups were not always unified; in some countries, rival groups divided along communist and noncommunist lines. However, in France the clandestine National Council of the Resis¬ tance coordinated all French groups, which gave support to the Normandy Campaign and participated in the August 1944 uprising that helped liberate Paris. Resistance groups in other northern European countries also under¬ took military actions to help the Allied forces in 1944^15.

resistivity Electrical resistance of a conductor of unit cross-sectional area and unit length. The resistivity of a conductor depends on its com¬ position and its temperature. As a characteristic property of each mate¬ rial, resistivity is useful in comparing various materials on the basis of their ability to conduct electric current. As temperature increases, the resis¬ tivity of a metallic conductor usually increases and that of a semiconduc¬ tor usually decreases.

Resnais \ro-'na\, Alain (b. June 3, director. After studying at the French cinema school IDHEC, he made short films on the visual arts (Van Gogh [1948]) and documentaries (Night and Fog [1956]). His first fea¬ ture film, Hiroshima mon amour (1959), created a sensation with its alternation between past and present and is considered one of the earliest and best films of the New Wave. He continued his exploration of the complex themes of time and memory in Last Year at Marienbad (1961).

His later films include Muriel (1963), Stavisky (1974), My Ameri¬ can Uncle (1980), Love unto Death (1984), I Want to Go Home (1989),

Smoking/No Smoking (1993), and

J Same Old Song (1997).

H resonance In physics, the rela¬

tively large selective response of an

tm object or a system that vibrates in

y step with an externally applied vibration. Acoustical resonance is the vibra¬

tion induced in a string of a given pitch when a note of the same pitch is produced nearby, in the sound box of an instrument such as a guitar, or in the mouth or nasal cavity when speaking. Mechanical resonance, such as that produced in a bridge by wind or by marching soldiers, can even¬ tually produce wide swings great enough to cause the bridge’s destruc¬ tion. Resonance in frequency-sensitive electrical circuits makes it possible for certain communication devices to accept signals of some frequencies while rejecting others. Magnetic resonance occurs when electrons or atomic nuclei respond to the application of magnetic fields by emitting or absorbing electromagnetic radiation. See also nuclear magnetic resonance.

Respighi \re-'spe-ge\, Ottorino (b. July 9, 1879, Bologna, Italy—d. April 18, 1936, Rome) Italian composer. After musical studies in Bolo¬ gna (1891-1901), he played viola in a Russian orchestra and studied with Nikolay Rimsky-Korsakov, from whom he learned much about orchestra¬ tion. His best-known works are the colourful tone poems The Fountains of Rome (1916) and The Pines of Rome (1924). Interested in early music, he also produced works such as Gli uccelli (1927), based on works by Jean-Philippe Rameau, and La Boutique fantasque, based on works by Gio¬ acchino Rossini.

respiration Process of taking in air for oxygen and releasing it to dis¬ pose of carbon dioxide. The amount of air inhaled and exhaled in an aver¬ age human breath (tidal volume) is about one-eighth the amount that can be inhaled after exhaling as much as possible (vital capacity). Nerve cen¬ tres in the brain regulate the movements of muscles of respiration (dia¬ phragm and chest wall muscles). Blood in the pulmonary circulation brings carbon dioxide from the tissues to be exhaled and takes up oxygen from the air in the pulmonary alveoli to carry it to the heart and the rest of the body. Because the body stores almost no oxygen, interruption of respiration—by asphyxiation, drowning, or chest muscle paralysis —for more than a few minutes can cause death. Disorders affecting respiration include allergy, asthma, bronchitis, emphysema, pneumonia, and tuberculosis. See also respiratory system; respiratory therapy.

respiratory distress syndrome or hyaline membrane dis¬ ease Common complication in newborns, especially after premature birth. Symptoms include very laboured breathing, bluish skin tinge, and low blood oxygen levels. Insufficient surfactant in the pulmonary alveoli raises surface tension, hampering lung expansion. The alveoli collapse (see atelectasis), and a “glassy” (hyaline) membrane develops in the alveolar ducts. Once the leading cause of death in premature infants, the syndrome is now usually treated for a few days with a mechanical ventilator (see respiratory therapy), with no aftereffects. An adult respiratory distress syn¬ drome (ARDS) can follow lung injury.

respiratory system Organ system involved in respiration. In humans, the diaphragm and, to a lesser extent, the muscles between the ribs gen¬ erate a pumping action, moving air in and out of the lungs through a sys¬ tem of pipes (conducting airways), divided into upper and lower airway systems. The upper airway system comprises the nasal cavity (see nose), siNUSes, and pharynx; the lower airway system consists of the larynx, tra¬ chea, bronchi, bronchioles, and alveolar ducts (see pulmonary alveolus). The blood and cardiovascular system can be considered elements of a working respiratory system. See also thoracic cavity. See illustration on opposite page.

respiratory therapy Medical profession concerned with assisting the respiratory function of individuals who have severe lung disorders. Prac¬ tices include suctioning to clear secretions from the airway, use of aero¬ sol mists (sometimes medicated) or gases to ease breathing, and tilting the body and chest percussion to promote drainage. A respiratory thera¬ pist also manages mechanical ventilation, a process in which a machine generates a controlled flow of a gas mixture into the airway of a patient who cannot breathe efficiently.

restaurant Establishment where refreshments or meals are served to paying guests. Though inns and taverns served simple fare to travelers for centuries, the first modern restaurant where guests could order from a var¬ ied menu is thought to have belonged to A. Boulanger, a soup vendor who opened his business in Paris in 1765. The sign above his door advertised restoratives, or restaurants, referring to his soups and broths. By 1804 Paris had more than 500 restaurants, and France soon became internationally famous for its cuisine. Other European restaurants include the Italian trat- torie, taverns featuring local specialties; the German Weinstuben, informal restaurants with a large wine selection; the Spanish tapas bars, which serve a wide variety of appetizers; and the public houses of England. Asian res¬ taurants include the Japanese sushi bars and teahouses serving formal Kai- seki cuisine as well as the noodle shops of China. Most U.S. restaurant innovations have revolved around speed. The cafeteria originated in San Francisco during the 1849 gold rush; cafeterias feature self-service and offer a variety of foods displayed on counters. The U.S. also pioneered fast- food restaurants such as White Castle (founded 1921) and McDonald’s (see Ray Kroc), usually operated as chains and offering limited menus.

Reston, James (Barrett) (b. Nov. 3, 1909, Clydebank, Dumbarton¬ shire, Scot.—d. Dec. 6, 1995, Washington, D.C., U.S.) Scottish-born U.S. columnist and editor. His family moved to the U.S. when he was 10 years old. He was a sportswriter before joining The New York Times in 1939, where he worked as a reporter, a nationally syndicated columnist, Wash¬ ington bureau chief (1953-64), executive editor (1968-69), and vice president (1969-74) before retiring in 1989. One of the most influential U.S. journalists, he had unrivaled personal access to U.S. presidents and world leaders and was often the first to break major stories. He won two Pulitzer Prizes (1945, 1957), helped create the first Op-Ed page (1970; a forum for columnists’ opinion pieces), and recruited and trained many talented young journalists.

1922, Vannes, France) French film

Resnais

COURTESY OF THE FRENCH FILM OFFICE, NEW YORK

Restoration ► retriever I 1611

tertiary ^ bronchus

upper or

-left

primary or principal bronchus

secondary

bronchus

nasal turbinate

epiglottis pharynx -

nasal cavity "vestibule of the nose

‘-oral cavity

diaphragm

terminal bronchiole

larynx

trachea

superior lobe

horizontal

fissure

lower

oblique

fissure

inferior

lobe

bronchiole

respiratory

bronchiole

a veo us

alveolar duct

a veo ar sac

As air enters the nasal cavity through the nostrils, it is warmed and moistened by mucous membranes of the nasal turbinates before entering the pharynx. Stiff hairs lining the vestibule inside the nostrils help filter the entering air. The air-filled sinuses adjacent to the nasal cavity produce mucus. The larynx connects the pharynx with the trachea or windpipe. The cartilaginous epiglottis prevents food from entering the larynx during swallowing. A left and right primary bronchus supply each lung with air from the trachea. They divide into smaller secondary and tertiary bronchi; the smallest divisions, bronchioles, lead to the cup-shaped, thin-walled alveoli, which occur in clusters (alveolar sacs). Oxygen and carbon dioxide are exchanged between the alveoli and surrounding capillaries. Oblique fissures or grooves of each lung separate the upper lobe from the lower lobe. The horizontal, or trans¬ verse, fissure of the right lung forms a middle lobe. Movement of the diaphragm along with the ribs and rib muscles causes expansion and contraction of the lungs during breathing.

Restoration Restoration of the monarchy in England in 1660. It marked the return of Charles II as king (1660-85) following the period of Oliver Cromwell’s Commonwealth. The bishops were restored to Parliament, which established a strict Anglican orthodoxy. The period, which also included the reign of James II (1685-88), was marked by an expansion in colonial trade, the Anglo-Dutch Wars, and a revival of drama and litera¬ ture (see Restoration literature).

Restoration literature English literature written after the Restoration of the monarchy in 1660 following the period of the Commonwealth. Some literary historians equate its era with the reign of Charles II (1660-85), while others add the reign of James II (1685-88). Many typical modern lit¬ erary forms (e.g., the novel, biography, history, travel writing, and journal¬ ism) began to develop with sureness during the Restoration period. Pamphlets and poetry (notably that of John Dryden) flourished, but the age is chiefly remembered for its glittering, critical, and often bawdy comedies of manners by such playwrights as George Etherege, Thomas Shadwell, Wil¬ liam Wycherly, John Vanbrugh, William Congreve, and George Farquhar.

restraint of trade Preventing of free competition in business by some action or condition such as price-fixing or the creation of a monopoly. The U.S. has a long-standing policy of maintaining competition among busi¬ ness enterprises through antitrust laws, the best-known of which, the Sher¬ man Antitrust Act of 1890, declared illegal “every contract, combination...or conspiracy in restraint of trade or commerce.”

restriction enzyme Protein (more specifically, an endonuclease) pro¬ duced by bacteria that cleaves DNA at specific sites along its length.

Thousands have been found, from many different bacteria; each recog¬ nizes a specific nucleotide sequence. In the living bacterial cell, these enzymes destroy the DNA of certain invading viRUSes (bacteriophages), thus placing a “restriction” on the number of viral strains that can cause infec¬ tion; the bacterium’s own DNA is protected from cleavage by methyl (—CH 3 ) groups, which are added by enzymes at the recognition sites to mask them. In the laboratory, restriction enzymes allow researchers to isolate DNA fragments of interest, such as those that contain genes, and to recombine them with other DNA molecules; for this reason they have become very powerful tools of recombinant DNA biotechnology (see DNA RECOMBINATION).

restrictive covenant In property law, an agreement acknowledged in a deed or lease that restricts the free use or occupancy of property, such as by forbidding commercial use or certain types of structures. The restric¬ tive covenant is as old as the law of property, being well-established in Roman law. The term is also used in business law to refer to an agree¬ ment whereby one party promises not to engage in the same business or a similar business in a particular area for a period of time.

retailing Selling of merchandise directly to the consumer. Retailing began several thousand years ago with peddlers hawking their wares at the earliest marketplaces. It is extremely competitive, and the failure rate of retail establishments is relatively high. Price is the most important arena of competition, but other factors include convenience of location, selec¬ tion and display of merchandise, attractiveness of the establishment, and reputation. The diversity of retailing is evident in the many forms it now takes, including vending machines, door-to-door and telephone sales, direct- mail marketing, the Internet, discount houses, specialty stores, department stores, supermarkets, and consumer cooperatives.

retaining wall or revetment Wall constructed to hold in place a mass of earth or prevent the erosion of an embankment. It may also be battered, with the face inclined toward the load it is bearing. The most basic type of reinforced retaining wall is the massive concrete gravity wall, which is prevented from falling over by the sheer weight and vol¬ ume of its mass. A cantilever (L-shaped) retaining wall resists overturn¬ ing by means of cantilever footings, spread footings (see foundation) shaped to resist overturning and sliding.

reticuloendothelial Vre-.tik-yo-lo-.en-do-'the-le-olN system or macrophage \ , mak-r9- 1 faj\ system or mononuclear phago¬ cyte system Part of the body’s defenses, consisting of a class of cells widely distributed in the body. Reticuloendothelial cells filter out and destroy bacteria, viRUSes, and foreign substances and destroy worn-out or abnormal cells and tissues. Precursor cells in bone marrow develop into monocytes (see leukocyte), which are released into the bloodstream. Most enter body tissues, developing into much larger cells called macrophages, with different appearances in various locations. Some roam through the circulation and between cells and can coalesce into a single cell around a foreign object to engulf it. Reticuloendothelial cells also interact with lym¬ phocytes in immune reactions. Cells in the spleen destroy old red blood cells and recycle their hemoglobin; uncontrolled, this process causes ane¬ mia. Tumours of the reticuloendothelial system can be localized or wide¬ spread throughout the body. See also lymphatic system.

retina Vre-Cn-oV Layer of nerve tissue covering the back two-thirds of the eyeball. Light focused onto the retina by the lens of the eye stimulates two types of light-sensitive cells: rods, which are sensitive to low light levels, and cones, which provide detailed vision and colour perception. Chemical changes in these cells trigger nerve impulses, which are assembled by complex connections among retinal nerves into a pattern to be carried through the optic nerve to the visual centres of the brain. Dis¬ orders affecting the retina or the macula in its centre decrease vision and can cause blindness. See also DETACHED RETINA; MACULAR DEGENERATION.

retriever Any of several dog breeds, bred to retrieve game, that have a thick, water-resistant coat, keen sense of smell, and “soft” mouth that does not damage game. Retrievers are 22-24 in. (55-62 cm) tall and weigh 55-75 lbs (25-34 kg). The golden retriever has a golden- brown coat that is long on the neck.

Golden retriever.

SALLY ANNE THOMPSON

1612 I retrograde motion ► revenue sharing

legs, and tail. The Labrador retriever has a short black or brown coat. Both are often used as guide dogs, and both are highly popular as pets. Other retriever breeds include the Chesapeake Bay, curly-coated, and flat-coated retrievers.

retrograde motion In astronomy, the actual or apparent motion of a body in a direction opposite to that of the predominant (direct or prograde) motions of similar bodies. Observationally and historically, retrograde motion refers to the apparent reversal of the planets’ motion through the stars for several months in each synodic period. This required a complex explanation in Earth-centred models of the universe (see Ptolemy) but was naturally explained in heliocentric models (see Copernican system) by the apparent motion as Earth passed by a planet in its orbit. It is now known that nearly all bodies in the solar system revolve and rotate in the same coun¬ terclockwise direction as viewed from a position in space above Earth’s North Pole. This common direction probably arose during the formation of the solar nebula. The relatively few objects with clockwise motions (e.g., the rotation of Venus, Uranus, and Pluto) are also described as retrograde.

retrovirus \ l re-tro-'vI-r9s\ Any of a group of viruses that, unlike most other viruses and all cellular organisms, carry their genetic blueprint in the form of RNA. Retroviruses are responsible for some cancers and viral infections of animals, and they cause at least one type of human cancer. The retrovirus HIV is the cause of AIDS in humans. The name signifies that they use RNA to synthesize DNA, the reverse of the usual cell pro¬ cess. This process makes it possible for genetic material from a retrovi¬ rus to enter and become a permanent part of the genes of an infected cell.

Retton, Mary Lou (b. Jan. 24, 1968, Fairmont, W.Va., U.S.) U.S. gymnast. Retton began studying dance and acrobatics at age 4. At the 1984 Olympic Games she received perfect scores in her final two events to win a dramatic victory in the combined exercises, becoming the first Ameri¬ can woman gymnast to win an individual Olympic gold medal. Her style, exhibiting speed, accuracy, and power, served to transform women’s gym¬ nastics. She was the first gymnast inducted into the U.S. Olympics Hall of Fame (1985).

Reuchlin Vr6ik-lin\, Johannes (b. Feb. 22, 1455, Pforzheim, Wiirttemberg—d. June 6, 1522, Bad Liebnzell) German humanist. After obtaining his law degree in 1481, he held court and judicial posts in Wiirttemberg and its capital, Stuttgart, from the 1480s until 1512. Second only to Desiderius Erasmus among the German humanists, Reuchlin was a pioneer in the scientific study of Classical Greek and translated many Classical texts. His grammar and lexicon, On the Fundamentals of Hebrew (1506), revolutionized Hebrew studies and advanced Old Testa¬ ment research. His opposition to the Dominicans’ plan to destroy all Hebrew literature was one of the great controversies prior to the outbreak of the Reformation, and in 1516 he was acquitted of heresy by a papal commission. Philipp Melanchthon was his nephew.

Reunion \re-'yun-y3n\ Island (pop., 2005 est.: 780,000) and French overseas department, Mascarene Islands, western Indian Ocean. Located 425 mi (684 km) east of Madagascar, Reunion is about 40 mi (65 km) long and 30 mi (50 km) wide and has an area of 968 sq mi (2,507 sq km). Its capital is Saint-Denis. It consists mainly of rugged mountains dissected by torrential rivers. Most of the population is of mixed ancestry, with African descent predominant. Reunion was settled in the 17th century by the French, who brought slaves from eastern Africa to work on coffee and sugar plantations. It was a French colony until 1946, when it became an overseas department of France. Its economy is based largely on the export of sugar. Other products include meat and milk products, rum, molasses, tobacco, geranium essence, and vanilla.

Reuter Vroi-tsrX, Paul Julius, Baron von Reuter orig. Israel Beer Josaphat (b. July 21, 1816, Kassel, Electorate of Hesse—d. Feb. 25, 1899, Nice, France) German founder of the news agency Reuters. He was a bank clerk and partner in a small publishing concern before initi¬ ating a prototype news service in Paris in 1849, using electric telegraphy and carrier pigeons in his network. He moved to England in 1851 and opened a telegraph office serving banks, brokerage houses, and leading business firms. He steadily extended his commercial news service, acquir¬ ing his first subscribing newspaper client in 1858. Undersea cables enabled him to expand the service to other continents.

Reuters Vroi-tsrzV British cooperative news agency. Founded in 1851 by Paul Julius Reuter, it was initially concerned with commercial news but began to serve a growing newspaper clientele after the London Morning

Advertiser subscribed in 1858. After a period of competition, Reuters and two rival agencies agreed on a division of territory and for many years held a virtual monopoly on world press services. The company remained in pri¬ vate hands until 1925, when its structure began moving toward a coopera¬ tive of British and Australasian press interests. By the late 20th century Reuters was a world leader in business and financial market coverage. In 1984 it became a public company under the name Reuters Group PLC.

Reuther Vru-thoA, Walter (Philip) (b. Sept. 1, 1907, Wheeling, W.Va., U.S.—d. May 9, 1970, Pellston, Mich.) U.S. labour leader. He became an apprentice tool- and diemaker at age 16. He traveled around the world in the 1930s, developing a lifelong distaste for communism after spending two years in a Soviet auto factory. He became a local union leader in Detroit, Mich., and helped organize sit-down strikes—during which he suffered brutal physical attacks—that made the United Automo¬ bile Workers (UAW) a power in the auto industry. As president of the UAW from 1946 until his death, he was an effective negotiator of wages-and- hours gains. He became president of the Congress of Industrial Organi¬ zations (CIO) in 1952 and was an architect of the AFL-CIO merger in 1955. He was second in power to George Meany at the AFL-CIO; how¬ ever, their repeated clashes, partly stemming from Reuther’s strong sup¬ port for civil rights and opposition to the Vietnam War, resulted in Reuther’s leading the UAW out of the AFL-CIO in 1968 and forming a short-lived federation with the Teamsters Union. He died in a plane crash.

revelation Transmission of knowledge from a god or gods to humans. In the Western monotheistic religions of Judaism, Christianity, and Islam, revelation is the basis of religious knowledge. Humans know God and his will because God has chosen to reveal himself to them. He may commu¬ nicate with his chosen servants through dreams, visions, or physical mani¬ festations and may inspire prophets who relay his message to the people. His will may also be translated directly into writing through the handing down of divine law (e.g., the Ten Commandments) or scripture (e.g., the Bible and the Qur’an). Other religions emphasize “cosmic” revelation, in which any and all aspects of the world may reveal the nature of a single under¬ lying divine power (e.g., Brahman in the Vedas).

Revelation, Book of or Revelations or Apocalypse of John

Last book of the New Testament. It consists of two main parts, the first containing moral admonitions to several Christian churches in Asia Minor, and the second composed of extraordinary visions, allegories, and sym¬ bols that have been the subject of varying interpretations throughout his¬ tory. A popular interpretation is that Revelation deals with a contemporary crisis of faith, possibly the result of Roman persecutions. It exhorts Chris¬ tians to remain steadfast in their faith and hold firm to the hope that God will ultimately vanquish their enemies. References to “a thousand years” have led some to expect that the final victory over evil will come after the completion of a millennium (see millennialism). Modem scholarship accepts that the book was written not by St. John the Apostle but by vari¬ ous unknown authors in the late 1st century ad. See also apocalypse.

Revels, Hiram R(hoades) (b. Sept. 1, 1822, Fayetteville, N.C., U.S.—d. Jan. 16, 1901, Aberdeen, Miss.) U.S. clergyman and politician. The son of free blacks, he traveled to Indiana and Illinois to receive the education that was denied him in the South. Ordained a minister, he became a pastor and principal of a Baltimore school for African Ameri¬ cans. In the American Civil War he helped organize African American vol¬ unteer regiments for the Union army. After the war he moved to Natchez, Miss., and was elected state senator in 1869. In 1870 he was elected to the U.S. Senate to fill the unexpired term of Jefferson Davis, becoming the first African American elected to that body. He later served as president of Alcorn A&M College (1871-74, 1876-83).

revenue bond or limited obligation bond Bond issued by a municipality, state, or public agency authorized to build, acquire, or improve a revenue-producing property such as a waterworks, electric gen¬ erating plant, or railroad. Unlike general-obligation bonds, which are repaid through a variety of tax sources, revenue bonds are payable from specified revenues only, usually the revenues from the facility for which the bond was originally issued. Revenue bonds typically pay interest rates higher than those of general-obligation bonds. The separation of the rev¬ enue bond obligation from a municipality’s other bond obligations allows the municipality to circumvent legislated debt limits.

revenue sharing Funding arrangement in which one government unit grants a portion of its tax income to another government unit. For example, provinces or states may share revenue with local governments.

reverberatory furnace ► Reymont I 1613

or national governments may share revenue with provinces or states. Laws determine the formulas by which revenue is shared, limiting the controls that the unit supplying the money can exercise over the receiver and specifying whether matching funds must be supplied by the receiver. Forms of revenue sharing have been used in several countries, including Canada, India, and Switzerland. From 1972 to 1986 the U.S. pursued a revenue-sharing program in which state and local governments received federal funds to spend as they saw fit.

reverberatory furnace Furnace used for smelting, refining, or melt¬ ing in which the fuel is not in direct contact with the contents but heats it by a flame blown over it from another chamber. Such furnaces are used in copper, tin, and nickel production, in the production of certain concretes and cements, and in aluminum recycling. In steelmaking, this process (now largely obsolete) is called the open-hearth process. The heat passes over the hearth and then radiates back (reverberates) onto the contents. The roof is arched, with the highest point over the firebox. It slopes downward toward a bridge of flues that deflects the flame so that it reverberates.

Revere, Paul (b. Jan. 1, 1735, Boston, Mass.—d. May 10, 1818, Bos¬ ton) American patriot and silversmith. He entered his father’s trade as a silversmith and engraver. An ardent supporter of the colonists’ cause, he took part in the Boston Tea Party. As the principal rider for Boston’s Com¬ mittee of Safety, he arranged to signal the British approach by having lan¬ terns placed in Boston’s Old North Church steeple: “One if by land and two if by sea.” On April 18, 1775, he set off to ride to Lexington to alert colonists that British troops were on the march and to warn Samuel Adams and John Hancock to flee. Though he was stopped by a British patrol, he was able to alert the patriot leaders; because of his warning, the minute- men were prepared for the Battle of Lexington and the start of the Ameri¬ can Revolution. His ride was celebrated in a famous poem by Henry W. Longfellow (1863). During the war. Revere constructed a powder mill to supply colonial arms. After the war he discovered a process for rolling sheet copper and opened a rolling mill that produced sheathing for ships such as the USS Constitution. He continued to design handsome silver bowls, flatware, and utensils that are museum pieces today.

revetment See retaining wall

Revillagigedo \ra-'ve-ya-he-'ha-th6\ Group of islands, Mexico, in the Pacific Ocean. The islands are located about 300 mi (500 km) south of the Baja California peninsula and about 370 mi (600 km) west of main¬ land Mexico. Covering a total land area of 320 sq mi (830 sq km), it con¬ sists of numerous volcanic islands. The largest, Socorro, reaches an elevation of 3,707 ft (1,130 m). The islands are rich in sulfur, fish, and guano and are administered by Colima state.

revivalism Reawakening of Christian values and commitment. The spiritual fervour of revival-style preaching, typically performed by itin¬ erant, charismatic preachers before large gatherings, is thought to have a restorative effect on those who have been led away from the right path. Various Protestant sects have experienced periods of revivalism at differ¬ ent times since the 17th century, and many, notably Methodism, came into being during revivalist periods. Common themes are strict interpretation of the Bible, rejection of literary or historical study of the Bible, emphasis on the conversion experience, and a call to live devoutly. Revivalism can be interpreted as a precursor of 20th-century Christian fundamentalism. See also Great Awakening; Dwight Moody.

revolution In politics, fundamental, rapid, and often irreversible change in the established order. Revolution involves a radical change in govern¬ ment, usually accomplished through violence, that may also result in changes to the economic system, social structure, and cultural values. The ancient Greeks viewed revolution as the undesirable result of societal breakdown; a strong value system, firmly adhered to, was thought to pro¬ tect against it. During the Middle Ages, much attention was given to find¬ ing means of combating revolution and stifling societal change. With the advent of Renaissance humanism, there arose the belief that radical changes of government are sometimes necessary and good, and the idea of revolution took on more positive connotations. John Milton regarded it as a means of achieving freedom, Immanuel Kant believed it was a force for the advancement of mankind, and G.W.F. Hegel held it to be the ful¬ fillment of human destiny. Hegel’s philosophy in turn influenced Karl Marx. See also coup d'etat.

Revolution of 1688 See Glorious Revolution Revolutionary War See American Revolution

Revolutions of 1848 Series of republican revolts against European monarchies. The revolutions began in Sicily and spread to France, the German and Italian states, and the Austrian Empire. In France the revo¬ lution established the Second Republic, and in central Europe liberal politi¬ cal reform and national unification appeared likely. However, the armies loyal to the monarchies soon reestablished their power and rescinded most of the promised reforms. The revolts eventually ended in failure and repression, and they were followed by widespread disillusionment among liberals.

revolver Pistol with a revolving cylinder that provides multishot action. Some early versions, known as pepperboxes, had several barrels, but as early as the 17th century pistols were being made with a revolving cham¬ ber to load cartridges into a single barrel. The first practical revolver was not designed until 1835, when Samuel Colt patented his version. He estab¬ lished the standard of a cylinder with multiple chambers, each of which successively locked in position behind the barrel and was discharged by pressure on the trigger. In Colt’s early single-action revolvers, the cylin¬ der revolved as the hammer was cocked manually. Double-action revolv¬ ers, in which the hammer is cocked and the cylinder revolves as the trigger is pulled, were developed soon afterward, along with metal cartridges.

revue Theatrical production of brief, loosely connected, often satirical skits, songs, and dances. Originally derived from the medieval French street fair, the modern revue dates from the early 19th century with the Parisian Folies Marigny and later at the Folies-Bergere. The English revue developed in two forms: one as the costume display and spectacle of the Court Theatre productions in the 1890s and another as the Andre Chariot Revues of the 1920s and the London Hippodrome shows, which empha¬ sized clever repartee and topicality. In the U.S. the Ziegfeld Follies began in 1907 and usually featured a star personality. Revues appeared periodi¬ cally on Broadway and West End stages until competition from movies and television moved the form to small nightclubs and improvisational theatres.

Rexroth, Kenneth (b. Dec. 22, 1905, South Bend, Ind., U.S.—d. June 6, 1982, Santa Barbara, Calif.) U.S. painter, essayist, poet, and translator. The largely self-educated Rexroth spent much of his youth traveling in the West, organizing and speaking for unions. His early poems were experimental, influenced by Surrealism; his later work was praised for its tight form and its wit and humanistic passion. He was an early champion of the Beat movement. His works include essays in Assays (1962) and With Eye and Ear (1970); and many translations of Japanese, Chinese, Greek, Latin, and Spanish poetry.

Rey See Rhagae

Reye syndrome Acute neurological illness in children, following influenza, chickenpox, or other viral infections. Vomiting, lethargy, and confusion begin as the child appeal’s to be recovering. These symptoms are followed hours or days later by drowsiness, disorientation, seizures, respiratory arrest, and coma. At worst, the syndrome includes fatty liver degeneration and potentially fatal brain swelling. There is no specific cure, but treatment of imbalances helps over 70% of patients survive (some with brain damage). The incidence has decreased since the recognition that it often follows use of aspirin or other salicylic acid derivatives in chil¬ dren during a viral illness. It can also result from aflatoxin or warfarin poisoning.

Reykjavik Vra-kya-,vek\ City (pop., 1999 est.: 109,152), capital of Ice¬ land. According to tradition, it was founded in 874 by the Norseman Ingolfur Arnarson. Until the 20th century it was a small fishing village at the southeastern corner of Faxa Bay, ruled and largely inhabited by Danes. It became the capital of a self-governing Iceland under the Danish king in 1918 and of the independent Republic of Iceland in 1944. During World War II it was a U.S. naval and air base. In 1986 arms-control talks between the U.S. and U.S.S.R. were held there. It is the commercial, industrial, and cultural centre of the island, its major fishing port, and the site of nearly half of the nation’s industries.

Reymont Vra-.montV, Wtadystaw (Stanistaw) or Wtadystaw Stanistaw Rejment (b. May 7, 1867, Kobiele Wielkie, Pol., Russian Empire—d. Dec. 5, 1925, Warsaw, Pol.) Polish novelist. He never finished his schooling and worked in his youth as a shop apprentice, a lay brother in a monastery, a railway official, and an actor. His short stories and novels are written in a naturalistic, factual style with short sentences. His best work, The Peasants (1904-09), is a four-volume chronicle of peasant life over the

1614 I Reynaud ► rhesus monkey

course of a year, written in peasant dialect. Translated into many languages, it won Reymont the 1924 Nobel Prize for Literature.

Reynaud Nra-'noV, Paul (b. Oct. 15, 1878, Barcelonnette, France—d. Sept. 21, 1966, Paris) French politician and premier (1940). After serv¬ ing in World War I, he served in the Chamber of Deputies (1919-24, 1928^-0) and in cabinet positions (1930-32). As minister of finance (1938^40) and premier (1940), he called on France to resist Nazi Ger¬ many. After the German invasion, Reynaud resigned rather than conclude an armistice; he was arrested and kept in captivity (1940-45). He returned to the Chamber of Deputies (1946-62) and helped draft the constitution of the Fifth Republic.

Reynolds, Sir Joshua (b. July 16, 1723, Plympton, Devon, Eng.—d. Feb. 23, 1792, London) British portrait painter. Son of a clergyman- schoolmaster, he was apprenticed to a London portraitist in 1740. His large group portrait The Eliot Family (c. 1746) reveals the influence of Anthony Van Dyck. The impressions he gained during two years in Italy (1750-52), particularly in Venice, inspired his painting for the rest of his life. He established a portrait studio in London in 1753 and was imme¬ diately successful. His early London portraits introduced new vigour into English portraiture. After 1760, with the increasing vogue for Greco- Roman antiquity, his style became increasingly Classical and self- conscious. He was elected the first president of the Royal Academy in 1768. Through his art and teaching, Reynolds led British painting away from the anecdotal pictures of the early 18th century toward the formal rhetoric of continental academic painting. His Discourses Delivered at the Royal Academy (1769-90), advocating rigorous academic training and study of the Old Masters, ranks among the most important art criticism of the time.

Reynolds, Osborne (b. Aug. 23, 1842, Belfast, Ire.—d. Feb. 21, 1912, Watchet, Somerset, Eng.) British engineer and physicist. Educated at Cambridge University, he became the first professor of engineering at the University of Manchester (1868). Best known for his work in hydrau¬ lics and hydrodynamics, he formulated the law of resistance in parallel channels (1883), the theory of lubrication (1886), and the standard math¬ ematical framework used in turbulence work (1889). He studied wave engineering and tidal motions in rivers and made pioneering contributions to the concept of group velocity. The Reynolds stress in fluids with tur¬ bulent motion and the Reynolds number are named for him.

Reynolds American Inc. formerly R.J. Reynolds Tobacco Holdings, Inc. U.S.-based tobacco company. Its origins date to the establishment of Richard Joshua Reynolds’s tobacco-plug factory in Win¬ ston, N.C., in 1875, producing plug tobacco (compressed cakes). The Reynolds Tobacco Co. became a major manufacturer of tobacco products, notably Camel, Winston, and Salem cigarettes. After embarking on a pro¬ gram of diversification in the 1960s, the firm adopted the name R.J. Rey¬ nolds Industries, Inc., in 1970 and purchased Nabisco Brands in 1985. The new company, named RJR Nabisco in 1986, was acquired in 1989 by Kohlberg Kravis Roberts & Co. (KKR) for $25 billion, the largest cor¬ porate transaction of its time. KKR divested its ownership in 1995. R.J. Reynolds returned to its primary business of tobacco marketing and merged with British-owned rival Brown & Williamson Tobacco Corp. in 2004 to create Reynolds American.

Reynolds number In fluid mechanics, a number that indicates whether the flow of a fluid (liquid or gas) is absolutely steady (in streamlined, or laminar flow) or on the average steady with small, unsteady changes (in turbulent flow; see turbulence). The Reynolds number, abbreviated N Re or Re, has no dimensions (see dimensional analysis) and is defined as the size of the flow—as, for example, the diameter of a tube (D) times the aver¬ age speed of flow (v) times the mass density of the fluid (p)—divided by its absolute viscosity (p). Osborne Reynolds demonstrated in 1883 that the change from laminar to turbulent flow in a pipe occurs when the value of the Reynolds number exceeds 2,100.

Rg Veda See Rig Veda

Rh blood-group system System for classifying blood according to presence or absence of the Rh antigen (factor) in erythrocytes. Rh-negative persons who receive Rh-positive blood transfusions produce antibodies to Rh factor, which attack red blood cells with the factor if they are ever received again, causing serious illness and sometimes death. The antibod¬ ies also attack the red cells of an Rh-positive fetus carried by an Rh-negative woman if she has had a previous Rh-positive transfusion or

pregnancy (see erythroblastosis fetalis). The Rh-negative trait is rare world¬ wide but more common in some ethnic groups. See also blood typing.

rhabdovirus V.rab-do-'vI-rosV Any of a group of viruses responsible for rabies and vesicular stomatitis (an acute disease of cattle and horses, char¬ acterized by blisters in and about the mouth, that resembles foot-and- mouth disease). The bullet-shaped virus particle is encased in a fatty membrane and contains RNA.

Rhaetia See Raetia

Rhaetian Vre-teonN Alps Segment of the central Alps located mainly in Switzerland but also extending along the Italian-Swiss and Austrian- Swiss borders. Bernina Peak, on the Italian border, is the highest point, at elevation 13,284 ft (4,049 m). In the eastern section is the Swiss National Park, founded in 1914, with an area of 65 sq mi (169 sq km); it is known for its rugged Alpine scenery and its wildlife.

Rhagae or Ragae \'ra-je\ Persian Rey Ancient city. Media. It was formerly one of the great cities of Iran; its ruins are at modern Rey, near Tehran. Settlement there dates from the 3rd millennium bc. Under the Sasanian dynasty (3rd-7th centuries ad), it was a centre of Zoroastrian¬ ism. It was captured by the Muslims in ad 641. It grew in importance until the 12th century, when it was weakened by religious conflicts. In 1220 it was destroyed by the Mongols, and its inhabitants were massacred. It was famous for its decorated silks and for ceramics. The 'Abbasid caliph HarOn al-Rashid, memorialized in The Thousand and One Nights, was born there c. 765. The only remaining architectural features are two towers.

Rhazes See al-RAzi

Rhea Vre-s\ Greek goddess, one of the Titans. Daughter of Uranus and Gaea, she married her brother Cronus, who swallowed all their children except Zeus, whom Rhea concealed. Zeus then overcame Cronus and restored his siblings.

rhea \'re-o\ Either of two ostrich-like species of South American three¬ toed ratite birds (family Rheidae). The common rhea ( Rhea americana ) is about 4 ft (120 cm) tall and weighs about 50 lbs (20 kg). It has luxu¬ riant plumage, brown or gray above and whitish below. Darwin’s rhea (Pterocnemia pennata ) is smaller and has white-tipped brownish plum¬ age. Rheas live in open country, often among grazing animals, and run from predators. They eat a wide variety of plants and animals. Both spe¬ cies are listed as endangered.

Rhee, Syngman (b. March 26, 1875, Whang-hae, Korea—d. July 19, 1965, Honolulu, Hawaii, U.S.) First president of the Republic of Korea (South Korea). The first Korean to earn a Ph.D. at a U.S. university (Prince¬ ton), he returned to Korea in 1910, the year Japan annexed Korea. Unable to hide his hostility toward Japanese rule, he left again for the U.S. in 1912. For the next 30 years he spoke out for Korean independence; in 1919 he was elected president of a provisional government in exile. As the only Korean leader well known to the U.S., Rhee was returned to Korea ahead of his rivals at the end of World War II; he was elected president of the Republic of Korea in 1948. He held that post until 1960, when opposition to his authoritarian policies (which included outlawing the opposition Pro¬ gressive Party) forced his resignation. He died in exile.

Rheims See Reims

rhesus \'re-sos\ monkey Sand-coloured macaque ( Macaca mulatto).

widespread in South and Southeast Asian forests. Rhesus monkeys are 17-25 in. (43-64 cm) long, exclud¬ ing the furry 8-12-in. (20-30-cm) tail, and weigh 10-24 lb (4.5-11 kg). They eat fruits, seeds, roots, herbs, and insects. They are held sacred in some parts of India. Hardy in captiv¬ ity, highly intelligent, and lively, they make good pets when young but may become bad-tempered as adults. They have been used frequently in medical research. The determination of the Rh (from rhesus) factor in human blood involves reaction with the blood of this species. See also Rh BLOOD-GROUP SYSTEM.

Rhesus monkeys (Macaca mulatto).

YLLA—RAPHO/PHOTO RESEARCHERS

rhetoric ► Rhodes I 1615

rhetoric Art of speaking or writing effectively. It may entail the study of principles and rules of composition formulated by critics of ancient times, and it can also involve the study of writing or speaking as a means of communication or persuasion. Classical rhetoric probably developed along with democracy in Syracuse (Sicily) in the 5th century bc, when dispossessed landowners argued claims before their fellow citizens. Shrewd speakers sought help from teachers of oratory, called rhetors. This use of language was of interest to philosophers such as Plato and Aris¬ totle because the oratorical arguments called into question the relation¬ ships among language, truth, and morality. The Romans recognized separate aspects of the process of composing speeches, a compartmental- ization that grew more pronounced with time. Renaissance scholars and poets studied rhetoric closely, and it was a central concern of humanism. In all times and places where rhetoric has been significant, listening and reading and speaking and writing have been the critical skills necessary for effective communication.

rheumatic \ru-'ma-tik\ fever Generalized disease caused by certain types of streptococcus bacteria. It occurs mostly in children and young adults. Symptoms may be mild or severe. Sudden fever, joint pain, and inflammation may begin days to weeks after a streptococcal infection, usually of the throat (see pharyngitis). Other symptoms may include skin nodules and rashes, chorea, abdominal pain, nosebleeds, and weight loss. Heart inflammation, with accompanying rapid heartbeat, murmurs, and enlargement, can lead to valve scarring, markedly shortening life. After recovery, survivors are prone to future attacks. Penicillin given when the initial infection is diagnosed can prevent it. Otherwise, salicylic acid derivatives or corticosteroids help the symptoms.

rheumatoid Vrii-mo-.tokB arthritis Chronic, progressive autoimmune disease causing connective-tissue inflammation, mostly in synovial joints. It can occur at any age, is more common in women, and has an unpredict¬ able course. It usually starts gradually, with pain and stiffness in one or more joints, then swelling and heat. Muscle pain may persist, worsen, or subside. Membrane inflammation and thickening scars joint structures and destroys cartilage. In severe cases, adhesions immobilize and deform the joints, and adjacent skin, bones, and muscles atrophy. If high-dose aspi¬ rin, ibuprofen, and other NSAIDs do not relieve pain and disability, low- dose corticosteroids may be tried. Physical medicine and rehabilitation with heat and then range-of-motion exercises reduce pain and swelling. Orthopedic appliances correct or prevent gross deformity and malfunc¬ tion. Surgery can replace destroyed hip, knee, or finger joints with pros- theses. There is also a juvenile form of the disease.

Rhiannon \hre-'a-non\ Welsh manifestation of the Gaulish horse god¬ dess Epona and the Irish goddess Macha. She is best known from the Mabinogion, in which she makes her appearance on a pale, mysterious steed and meets King Pwyll, whom she marries. Unjustly accused of kill¬ ing her infant son, she was forced to carry people on her back like a horse until she was vindicated by her son’s return.

Rhine, Confederation of the See Confederation of the Rhine

Rhine River German Rhein River, western Europe. Rising in the Swiss Alps, it flows north and west through western Germany to drain through the delta region of The Netherlands into the North Sea. It is 820 mi (1,319 km) long and navigable for 540 mi (870 km). Its many canals connect it with the Rhone, Marne, and Danube river systems. It has been an inter¬ national waterway since 1815 (see Congress of Vienna). It has played a prominent part in German history and legend. During World War II its course was a major line of defense. Major cities along its banks include Basel, Mannheim, Koblenz, Cologne, Duisburg, and Rotterdam.

Rhineland German Rheinland Region of Germany. It is located west of the Rhine River and encompasses the states of Saarland and Rhineland- Palantinate and portions of Baden-Wiirttemberg, Hesse, and North Rhine- Westphalia. The chief city of the Rhineland is Cologne. In the 19th century the Rhineland became the most prosperous area of Germany. After World War I, Allied troops occupied portions of the area on the border with France, and it was the scene of recurrent crises and controversies during the 1920s. In 1936 Adolf Hitler ordered German troops to enter the demilitarized zone of the Rhineland; weak objections by the Allies fore¬ shadowed Hitler’s later annexation of the Sudetenland.

rhinoceros Any of five extant African and Asian species (family Rhi- nocerotidae) of three-toed horned ungulates. One of the largest of all land animals (the white rhinoceros is second only to the elephant), the rhinoc¬

eros is particularly distinguished by one or two horns—growths of kera¬ tin, a fibrous hair protein—on its upper snout. All have thick, virtually hairless skin that, in the three Asian species, forms platelike folds at the shoulders and thighs. Rhinos grow to 8-14 ft (2.5-4.3 m) long and 3-6.5 ft (1.5-2 m) tall; adults weigh 3-5 tons. Most are solitary inhabitants of open grassland, scrub forest, or marsh, but the Sumatran rhino lives in deep forest. The African black rhino browses on succulent plants, the white and great Indian rhinos graze on short grasses, and the Sumatran and Javan rhinos browse on bushes and bamboo. In the second half of the 20th century, the rhinoc¬ eroses were brought to the brink of extinction by hunters, mostly seek¬ ing the horn, which is valued in Asia as an aphrodisiac. The white rhinoceros of Africa is no longer endangered, but the population of the other four species combined is only a few thou¬ sand, almost all of which live on reserves.

rhinovirus \ l ri-n6-'vl-r3s\ Any of a group of picornaviruses capable of causing common colds in humans. The virus is thought to be transmitted to the upper respiratory tract by airborne droplets. Because of the great number of cold viruses, vaccines against them are virtually impossible to develop. See also adenovirus.

rhizome Horizontal underground plant stem capable of producing the upward shoot and downward root systems of a new plant. This capabil¬ ity allows vegetative (asexual) propagation and enables plants to survive an annual unfavourable season underground. In some plants (e.g., water lilies, many ferns, and forest herbs), the rhizome is the only stem of the plant. In such cases, only the leaves and flowers are readily visible.

Rhode Island officially Rhode Island and Providence Plan¬ tations State (pop., 2000: 1,048,319), northeastern U.S. One of the New England states and the smallest U.S. state, it covers 1,212 sq mi (3,139 sq km); its capital is Providence. Rhode Island is bordered by Massachu¬ setts on the north and east, and Connecticut on the west. The Rhode Island Sound on the south is the basis of the state’s fishing industry. The origi¬ nal inhabitants of the area were Narragansett Indians. The first European settlement was in 1636 by Roger Williams and his followers, who were banished from Massachusetts; in 1663 King Charles II granted a charter to Williams. Though it never officially joined the New England colonies in King Philip's War, it suffered greatly when many settlements were burned. It was at the forefront of the fight against British customs laws that led to the American Revolution. An original state of the Union, in 1790 it was the 13th state to ratify the Constitution, agreeing only after the Bill of Rights was included. The state’s original charter remained in effect until Dorr’s Rebellion (see Thomas W. Dorr) in 1842 led to extension of suf¬ frage. The cotton-textile mill built by Samuel Slater in Pawtucket in 1790 initiated the Industrial Revolution in the U.S. Manufacturing is still impor¬ tant to the economy, and products include jewelry and silverware, textiles and clothing, and electrical machinery and electronics.

Rhode Island School of Design (RISD) One of the most eminent fine arts colleges in the U.S., located in Providence, R.I. It was founded in 1877 but did not offer college-level instruction until 1932. It combines professional arts training with a broad liberal arts curriculum, offering bachelor’s and master’s degrees in the design, fine arts, and other fields. Its art museum has extensive collections of American painting and deco¬ rative arts.

Rhodes Greek Rodhos Vr6-,th6s\ Island of Greece. It is the largest island of the Dodecanese group and the most easterly in the Aegean Sea. Its main city, Rhodes (pop., 2001: 53,709), lies at the northern tip of the island. The earliest known settlers were the Dorians c. 1000 bc. During the Classical period the island’s affiliations vacillated between Athens, Sparta, and Persia in attempts to preserve a balance of power. A devas¬ tating earthquake c. 225 bc destroyed the Colossus of Rhodes, one of the Seven Wonders of the World. In the medieval period Rhodes was occu-

African black rhino (Diceros bicornis).

CAMERA PRESS/PICTORIAL PARADE

1616 I Rhodes ► Rhodope Mountains

pied by the Byzantines, Muslims, and Knights of St. John (see Knights of Malta). The knights converted the island into a fortress and held it for two centuries until 1523, when the Turks took control. In 1912 it was taken from Turkey by Italy, and in 1947 it was awarded by treaty to Greece. A year-round tourist industry has brought prosperity to the island.

Rhodes, Alexandre de (b. March 15, 1591, Avignon, France—d. March 5, 1660, Esfahan, Iran) French missionary, the first Frenchman to visit Vietnam. He established a Jesuit mission in the region in 1619 and later estimated that he had converted some 6,700 Vietnamese to Roman Catholicism. Expelled in 1630, he spent 10 years teaching philosophy in Macau before returning, only to be exiled again in 1646. The Vatican sponsored a Vietnamese missionary program in 1658 based on de Rhodes’s ideas, but he himself was sent to Iran (Persia), where he died. He wrote a Vietnamese-Latin-Portuguese dictionary and perfected the romanized script Quoc-ngu (developed by earlier missionaries), which facilitated communicating Christian doctrines to the Vietnamese and increased the literacy rate among the population.

Rhodes, Cecil (John) (b. July 5, 1853, Bishop’s Stortford, Hertford¬ shire, Eng.—d. March 26, 1902, Muizenberg, Cape Colony) Financier, statesman, and empire builder of British South Africa. Rhodes grew up in the English countryside and in 1871 was sent to assist his brother in business in South Africa, where he became interested in diamond mining. He founded De Beers Consolidated Mines (1888), and by 1891 his com¬ pany was mining 90% of the world’s diamonds. Seeking expansion to the north and dreaming of building a Cape-to-Cairo railway, he persuaded Britain to establish a protectorate over Bechuanaland (1884), clashing with Boer president Paul Kruger. He obtained digging concessions from Lobengula (1889), but in 1893 Rhodes overran him militarily. At his insti¬ gation Britain chartered the British South Africa Co. (1889) and put Rhodes in charge. He extended the company’s control to two northern provinces, which were eventually named after him as Southern Rhodesia (now Zimbabwe) and Northern Rhodesia (now Zambia). Interested in the mineral-rich Transvaal, he plotted to overthrow Kruger (1895); the attempt was botched by Leander Starr Jameson, and Rhodes was forced to resign as prime minister of Cape Colony and head of the British South Africa Co. His last years were marked by disappointment and scandal brought about by the scheming of Princess Radziwill. His will bequeathed most of his fortune to establishing the Rhodes scholarship.

Rhodes, Colossus of Enormous that towered more than 100 ft (30 m) over the harbour at the city of Rhodes in Greece. The work of Chares of Lindos, the statue commemorated the raising of Demetrios Poliorcetes’ long siege of Rhodes (305-304 bc). One of the Seven Wonders of the World, it was toppled by an earth¬ quake c. 225 bc. The fallen Colossus was left in place until ad 653, when raiding Arabs broke up its remains and sold the bronze for scrap.

Rhodes scholarship Grant to attend the University of Oxford. The program was established in 1902 by the will of Cecil Rhodes. Until 1976, candidates had to be unmarried male residents in a Commonwealth coun¬ try, the U.S., or South Africa. In 1976 women were accepted. Two candi¬ dates each year are also chosen from Germany. The scholarships, which are highly competitive, are usually fi

statue of the sun god Helios

Colossus of Rhodes, constructed c. 292-280 bc, wood engraving recon¬ struction by Sidney Barclay, c. 1875.

HISTORICAL PICTURES SERVICE, CHICAGO

two years.

Rhodesia Region, south-central Africa, now divided into Zimbabwe in the south and Zambia in the north. Named after British colonial adminis¬ trator Cecil Rhodes, it was administered by the British South Africa Com¬ pany in the 19th century and exploited mostly for its gold, copper, and coal deposits. In 1911 it was divided into Northern and Southern Rhode¬ sia; Southern Rhodesia became a self-governing British colony (1923) and Northern Rhodesia a British protectorate (1924). They joined with Nyasa- land to become the Federation of Rhodesia and Nyasaland (1953-63). See also Malawi.

Rhodesia See Zimbabwe

Rhodesian ridgeback or African lion dog South African hound breed characterized by a narrow band of hair growing forward along its back, against the direction of the rest of the coat. The ridge is inher¬ ited from a half-wild local hunting dog that was crossbred with Euro¬ pean dogs. Strong, active, and of great endurance, it is trim and short- haired, with hanging ears and a glossy brown coat. It stands 24-27 in. (61-69 cm) and weighs 65-75 lbs (30-34 kg). It is an able guard and hunter (especially of lions) and a good companion.

Rhodian Sea Law \'ro-de-on\

Regulations governing trade and navigation in the Byzantine Empire.

Based on a statute in the Code of Jus¬ tinian and on ancient maritime law in Rhodes, the Rhodian Sea Law focused on liability for lost or dam¬ aged cargo. It divided the cost of the losses among the shipowner, the owners of the cargo, and the passengers, thus serving as a form of insurance against storms and piracy. It was effective from the 7th through the 12th century.

rhodium Metallic chemical element, one of the transition elements, chemical symbol Rh, atomic number 45. Chemically related to platinum, it is a precious, silver-white metal mainly used as an alloying agent for the latter element. Rhodium added to platinum in small amounts yields alloys that are harder and that lose mass at high temperatures more slowly than pure platinum. Such alloys are used for laboratory furnace crucibles, spark-plug electrodes, catalysts in very hot chemical environments (including automobile catalytic converters), and high-temperature thermo¬ couples. Because rhodium resists tarnishing at ordinary temperatures and is highly reflective, it is in demand as a surface electroplating for jewelry and other decorative articles. The plated metal is also used for reflecting surfaces in optical instruments.

rhodochrosite \ l ro-d3- , kro-,sIt\ Carbonate mineral composed of man¬ ganese carbonate (MnC0 3 ), a source of manganese for the ferromanga¬ nese alloys used in steel production. It is commonly found in ore veins formed at moderate temperatures, in high-temperature metamorphic deposits, and in sedimentary deposits.

rhododendron \,ro-d3-'den-dr3n\ Any of about 800 diverse species of woody plants that make up the genus Rhododendron in the heath family, notable for their attractive flowers and handsome foliage. They are native chiefly in the northern temperate zone, especially in South Asia and Malaysia. Some are evergreens, others deciduous. Some are low-growing ground covers; others are tall trees. Flowers are usually tubular to funnel- shaped and occur in a wide range of colours: white, yellow, pink, scarlet, purple, and blue. See also azalea.

rhodonite Vro-ds-.nlA Silicate mineral that occurs in various manganese ores, often with rhodochrosite. A manganese silicate, MnSi0 3 , with small amounts of iron and calcium, it is found in the Ural Mountains,

Sweden, Australia, California, New Jersey, and elsewhere. Rhodonite is the primary source of some impor¬ tant manganese oxide deposits, such as the manganese ores of India. Fine¬ grained rhodonite of clean, pink colour is a desirable gem and orna¬ mental stone.

Rhodope Vra-da-peX Moun¬ tains Mountain range, Balkan Pen¬ insula, southeastern Europe. Extending southeast from Bulgaria through Macedonia and Greece, the range is drained by tributaries of the Maritsa River. It forms an important climatic barrier, protecting the Aegean low-

Rhodonite from Pajsberg, Swed.

COURTESY OF THE FIELD MUSEUM OF NATURAL HISTORY, CHICAGO; PHOTOGRAPH, JOHN H. GERARD

Rhodesian ridgeback.

WALTER CHANDOHA

rhodopsin ► Ribera I 1617

lands from cold northerly winds. The mountains were a refuge for Slavic peoples during the period of Turkish rule (15th—19th century), and ancient customs survive. The lakes, river valleys, and extensive forests form the basis of a tourist industry.

rhodopsin \r6-'dap-son\ or visual purple Light-sensitive, purple-red organic pigment contained in the rod cells of the retina that allows the eye to see in black and white in dim light. It is composed of opsin, a protein, linked to retinal, a conjugated molecule (see conjugation) formed from vitamin A. Photons of light that enter the eye are absorbed by retinal and cause it to change its configuration, starting a biochemical chain of events that ends with impulses being sent along the optic nerve to the brain. In bright light, to protect rod cells from overstimulation, rhodopsin breaks down into retinal and opsin, both of which are colourless. In dim light or darkness the process is reversed (dark adaptation), and purple-red rhodop¬ sin is reformed. Similar light-sensitive compounds made of retinal and other opsin proteins are the pigments in the retina’s cone cells responsible for colour vision in bright light.

Rhone River River, Switzerland and France. A historic southern gate¬ way, as well as the only major European river flowing directly to the Mediterranean Sea, the Rhone is 505 mi (813 km) long and navigable for about 300 mi (485 km). It is Alpine in character, and its course has been shaped by neighbouring mountain systems. Rising in the Swiss Alps, it flows into Lake Geneva, then crosses into France through the Jura Moun¬ tains. It continues south through Lyon, Avignon, and Tarascon to Arles and enters the Mediterranean west of Marseille.

rhubarb Any of several species of the genus Rheum (family Polygo- naceae), especially R. rhaponticum (or R. rhabarbarum ), a hardy peren¬ nial grown for its large, succulent, edible leafstalks. Rhubarb is best adapted to the cooler parts of the tem¬ perate zones. The fleshy, tart, and highly acid leafstalks are used in pies, compotes and preserves, and some¬ times as the base of a wine or an aperitif. The roots withstand cold well. The huge leaves that unfold in early spring are toxic to cattle and humans; later in the season a large central flower stalk may bear numerous small, greenish-white flowers and angular, winged fruits. Rhubarb root has long been considered to have cathartic and purgative properties.

rhyme Type of echoing produced by the close placement of two or more words with similarly sounding final syllables. Rhyme is used in poetry (and occasionally in prose) to produce sounds that appeal to the ear and to unify and establish a poem’s stanzaic form. End rhyme (i.e., rhyme used at the end of a line to echo the end of another line) is most com¬ mon, but internal rhyme (occurring before the end of a line) is frequently used as an embellishment. Types of “true rhyme” include masculine rhyme, in which the two words end with the same vowel-consonant com¬ bination (stand/land); feminine rhyme (or double rhyme), in which two syllables rhyme (profession/discretion); and trisyllabic rhyme, in which three syllables rhyme (patinate/latinate).

rhyolite Vrl-o-.lItV Igneous rock that is the volcanic equivalent of gran¬ ite, whose chemical composition is similar. Rhyolites are known from all parts of the Earth and from all geologic ages; they are found mostly on the continents or their immediate margins, but small quantities have been described from remote islands.

Rhys Vres\, Jean orig. Ella Gwendolen Rees William (b. Aug. 24, 1890, Roseau, Dominica, Windward Islands, West Indies—d. May 14, 1979, Exeter, Devon, Eng.) Dominican-born British novelist. Rhys left the West Indies for London to study acting at age 16. She later moved to Paris, where she was encouraged to write by Ford Madox Ford. She earned acclaim for short stories and novels set in the bohemian world of Europe in the 1920s and ’30s, including Good Morning, Midnight (1939). After settling in Cornwall, she published nothing for nearly three decades before producing Wide Sargasso Sea (1966), a memorable novel about Mr. Roch¬ ester’s mad first wife in Charlotte Bronte’s Jane Eyre (see Bronte sisters); and two story collections.

rhythm and blues (R&B) Any of several closely related musical styles developed by African American artists. The various styles were based on a mingling of European influences with jazz rhythms and tonal inflections, particularly syncopation and the flatted blues chords. They grew out of the blues of the rural South, which blended work chants with songs of deep emotion, and were greatly influenced by gospel music. Three major forms were distinguishable. The earliest, called race , was the style of the “jump” band, which emphasized strong rhythm, solo work (espe¬ cially by saxophones), and vocals in a shout-blues manner. A second form, often called Chicago blues, was exemplified by performers such as Muddy Waters and was typically played by a small group with amplified instru¬ ments. The third major form was primarily vocal, featuring close, gospel- influenced harmonies often backed by an orchestra. In the mid-1950s the term rhythm and blues was adopted by the music industry for music intended for the African American audience; with the gradual disappear¬ ance of racial barriers, the Chicago blues style began to seem less a vital form than a folk tradition, while the gospel style was transformed into the soul music of vast appeal. Rhythm and blues was the chief antecedent of ROCK MUSIC.

rhythm and metre Two aspects of the organization of time in music. Rhythm is the placement of musical sounds in time. Metre, like poetical metre, is usually a regular pattern of beats and provides the context in which rhythm is understood. In Western notated music, metre is indicated by means of a time signature—in which the lower number specifies the basic unit or subunit of the beat (e.g., 8 usually indicates that eighth-notes are the basic subunit) and the upper number specifies the number of beats in a measure—at the beginning of a piece or movement, and by the ver¬ tical bar lines that divide the piece into measures.

rhythmic sportive gymnastics Athletic competition related to gym¬ nastics and dance in which participants, individually or in groups, per¬ form exercise routines with the aid of hand apparatuses such as ropes, hoops, balls, clubs, and ribbons. In scoring points, artistry counts more than acrobatics. The sport dates from the 18th century. Though some gymnasts participated at the Olympic Games from 1948 to 1956, not until 1984 did it become an official Olympic competitive event.

Ribalta \re-'bal-ta\, Francisco (b. 1565, Castellon de la Plana, Spain—d. Jan. 12, 1628, Valencia) Spanish painter. His early works are Mannerist. After settling in Valencia in 1598, he developed a darker and more naturalistic style (e.g., his Santiago altarpiece, 1603) under the influ¬ ence of Caravaggio. After 1612 he achieved originality and grandeur in such paintings as Christ Embracing St. Bernard. His later paintings, marked by powerfully modeled forms, simplicity of composition, and naturalistic lighting, anticipate the work of Diego Velazquez, Francisco Zurbaran, and Jose de Ribera.

Ribat See Rabat

Ribaut \re-'b6\, Jean (b. c. 1520, Dieppe, France—d. Oct. 12, 1565, Florida) French naval officer and colonizer. He served in the French navy under Gaspard II de Coligny, who in 1562 sent him to found a French Huguenot colony in Florida. He landed at the mouth of the St. Johns River (Florida), then sailed north to establish Charlesfort (now in South Caro¬ lina). He returned to France, then was sent back to Florida (1565) to rein¬ force the French colony of Fort Caroline on the St. Johns River. Spanish claims to the region led to the attack and destruction of the colony by Pedro Menendez de Aviles, who massacred the French, including Ribaut.

Ribbentrop Vri-bsn-.trapV Joachim von (b. April 30, 1893, Wesel, Ger.—d. Oct. 16, 1946, Niirnberg) German diplomat and foreign minis¬ ter under the Nazi regime. After serving in World War I, he became a wine merchant. He met Adolf Hitler in 1932 and became his chief adviser on foreign affairs. He negotiated the Anglo-German Naval Agreement and served as ambassador to Britain (1936-38), advising Hitler that Britain could not aid Poland effectively. As foreign minister (1938—45), he nego¬ tiated the Pact of Steel with Italy, the German-Soviet Nonaggression Pact, and the Tripartite Pact with Japan and Italy. His influence waned in World War II, after which he was found guilty at the Niirnberg trials and hanged.

Ribble, River River, northwestern England. It is 75 mi (120 km) long. It rises in North Yorkshire and flows south and west through Lancashire into the Irish Sea through an estuary extending from Preston. The channel to the Irish Sea coast has been straightened to provide a shipping lane to Preston.

Ribera \re-'ber-3\, Jose de or Jusepe de Ribera (baptized Feb. 17, 1591, Jativa, Spain—d. Sept. 2, 1652, Naples) Spanish painter and

Rhubarb (Rheum rhaponticum )

DEREK FELL

1618 I riboflavin ► Richard II

printmaker. Though bom in Spain, where he is said to have trained under Francisco Ribalta, he spent most of his life in Naples (then a Spanish pos¬ session). Most of his works are of religious subjects. Dramatic light and shadow and sometimes horrific detail emphasize the mental and physical suffering of penitent or martyred saints, as in The Martyrdom of St. Bar¬ tholomew (c. 1630). In later works his modeling is softer, his colours are richer, and he demonstrates strong human sympathy, as in The Clubfooted Boy (1642). His etchings are among the finest produced in Italy and Spain in the Baroque period.

riboflavin V.ri-bo-'fla-vonX or vitamin B 2 Yellow, water-soluble organic compound, abundant in whey and egg white. It has a complex structure incorporating three rings. Green plants and most microorgan¬ isms can synthesize it; animals need to acquire it in their diet. It exists in combined forms as coenzymes and functions in the metabolism of carbohy¬ drates and amino acids. A syndrome resembling pellagra is thought to result from riboflavin deficiency. See also flavin.

ribose \'rI-,bos\ Five-carbon sugar found in RNA. (In DNA the corre¬ sponding sugar is the closely related deoxyribose.) A ribose molecule combined with adenine, guanine, cytosine, or uracil forms a nucleoside; adding a phosphate group forms a nucleotide. The ribose of one nucleotide joins with the phosphate of the next to form the RNA backbone. Ribose phosphates are components of various coenzymes and are used by micro¬ organisms in synthesizing histidine.

ribosome Vri-ba-.somX Tiny particle, the site of protein synthesis, that is present in large numbers in living cells. They occur both as free par¬ ticles within cells and, in eukaryotes, as particles attached to the mem¬ branes of the endoplasmic reticulum. They are 40% protein and 60% RNA. Ribosomes account for a large proportion of the total RNA of a cell. Pro¬ teins newly formed on ribosomes detach and migrate to other parts of the cell to be used.

Ricardo, David (b. April 18/19, 1772, London, Eng.—d. Sept. 11, 1823, Gatcombe Park, Gloucestershire) British economist. The son of a Dutch Jew, he followed his father into the London stock exchange, where he made a fortune before turning to the study of political economy, in which he was influenced by the writings of Adam Smith. His writings in support of a metal currency standard were influential. In his major work, The Principles of Political Economy and Taxation (1817), he examined the movement of wages and the determination of value, asserting that the domestic values of commodities were largely determined by the labour required for their production. His Iron Law of Wages stated that attempts to improve the real income of workers were futile and that wages tended to stabilize at subsistence level. Though many of his ideas are obsolete, he was a major figure in the development of classical economics and is credited as the first person to systematize economics.

Ricci \'ret-che\, Matteo (b. Oct. 6, 1552, Macerata, Papal States—d. May 11, 1610, China) Italian Jesuit missionary who introduced Christian¬ ity to China. From a noble family, he was educated by the Jesuits, whose order he joined after studying law in Rome. He volunteered for mission¬ ary work overseas, arrived in Goa in 1578, and proceeded to China in 1582. China’s interior was closed to foreigners when he arrived, but his willingness to adopt the Chinese language and culture gave him entry. In 1597 he was appointed director of Jesuit activities in China. In 1599 he settled in Nanjing, where he studied astronomy and geography. In 1601 he was finally admitted to Beijing, where he preached the Gospel, taught science to scholars, and translated Christian works into Chinese.

Riccio \'ret-cho,\ English Vrich-e-.oV, David orig. Davide Rizzio (b. c. 1533, Pancalieri, near Turin, Piedmont—d. March 9, 1566, Edinburgh, Scot.) Secretary to Mary, Queen of Scots. The son of a musician, he accompanied the duke of Savoy’s ambassador to Scotland and entered Mary’s service as a musician (1561). He became her close adviser and helped arrange her marriage to Lord Darnley (1565). Disliked because of his arrogance, Riccio was an impediment to the Scottish nobles’ plan to remove Mary. While at dinner in Mary’s palace, he was seized by an armed band of nobles, including Lord Ruthven, and stabbed to death.

rice Edible starchy cereal grain and the annual grass ( Oryza sativa, family Poaceae, or Gramineae) that produces it. Roughly one-half of the world’s population, including almost all of East and Southeast Asia, depends on rice as its principal staple food. First cultivated in India more than 4,000 years ago, rice was planted gradually westward and is now cultivated widely in flooded fields (paddies) and river deltas of tropical, semitropical,

and temperate regions. Growing to about 4 ft (1.2 m) in height, rice has long, flat leaves and an inflorescence made up of spikelets bearing flowers that produce the fruit, or grain.

Removal of just the husk produces brown rice, containing 8% protein and a source of iron, calcium, and B vitamins. Removal of the bran layer leaves white rice, greatly diminished in nutrients. Enriched white rice has added B vitamins and minerals.

So-called wild rice ( Zizania aquat- ica) is a coarse annual grass of the same family whose cereal grain, now often considered a delicacy, has long been an important food of North American Indians.

Rice, Jerry (Lee) (b. Oct. 13,

1962, Starkville, Miss., U.S.) U.S. gridiron football player. He won All-America honours at Mississippi Val¬ ley State University. As a wide receiver for the San Francisco 49ers (1985-2000), he was part of three Super Bowl championship teams (1988, 1989, and 1994). Standing 6 ft 2 in. (1.9 m). Rice was larger than the typical NFL wide receiver of his era, and he used his size and strength to overmatch defenders; he was also an exceptional runner. He completed his career in 2005 as the all-time NFL leader in touchdowns (207), recep¬ tions (1,549), receiving yards (22,895), and combined yardage (23,546).

Rice University Private university in Houston, Texas, U.S. It was founded in 1891 and endowed by William Marsh Rice. It has schools of humanities, social sciences, architecture, music, natural sciences, and engineering and a graduate school of administration. It offers both under¬ graduate and graduate degrees in numerous fields.

Rich, Adrienne (Cecile) (b. May 16, 1929, Baltimore, Md., U.S.) U.S. poet, scholar, and critic. She was a student at Radcliffe College when her poems were chosen for publication in the Yale Younger Poets series; the resulting volume, A Change of World (1951), reflected her formal mas¬ tery. Her subsequent work traces a transformation from well-crafted but imitative poetry to a highly personal and powerful style. Her increasing commitment to the women’s movement and a lesbian/feminist aesthetic influenced much of her work. Among her collections are Diving into the Wreck (1973, National Book Award) and The Dream of a Common Lan¬ guage (1978). She also wrote compelling books of nonfiction, including Of Woman Born (1976; National Book Award), On Lies, Secrets, and Silence (1979), and What Is Found There (1993).

Rich, Buddy orig. Bernard Rich (b. June 30/Sept. 30, 1917, Brook¬ lyn, N.Y., U.S.—d. April 2,1987, Los Angeles, Calif.) U.S. bandleader and drummer. Rich was a child-prodigy vaudeville performer known as “Baby Traps, the Drum Wonder.” He played with several of the great swing bands, notably those of Artie Shaw (1939) and Tommy Dorsey (1939-42,1944-46), before forming his own big band. In small ensembles, he worked with many of the greatest jazz musicians in concerts and recordings during the 1950s. The clarity and speed of his drumming made him legendary.

Richard I known as Richard the Lionheart(ed) French Richard Coeur de Lion (b. Sept. 8, 1157, Oxford, Eng.—d. April 6, 1199, Chalus, Duchy of Aquitaine) Duke of Aquitaine (1168-99) and Poitiers (1172-99) and king of England, duke of Normandy, and count of Anjou (1189-99). He inherited Aquitaine from his mother, Eleanor of Aquitaine. Denied real authority there, he rebelled against his father, Henry II (1173— 74) and later enlisted Philip II of France in a successful campaign against Henry (1189). Crowned king of England on Henry’s death that year, Richard embarked on the Third Crusade (1190), stopping in Sicily to name Tancred king and conquering Cyprus. He won victories in the Holy Land, but, after failing to gain Jerusalem, he signed a truce (1192) with Sala- din. On his way home Richard was captured by Leopold of Austria and turned over to Henry VI of Germany, who imprisoned him until a ransom was paid (1194). Richard returned to England and reclaimed the throne from his brother John, then spent the rest of his life in Normandy fight¬ ing against Philip II.

Richard II (b. Jan. 6, 1367, Bordeaux—d. February 1400, Pontefract, Yorkshire, Eng.) King of England (1377-99). The grandson of Edward III,

Rice (Oryza sativa).

GRANT HEILMAN

Richard III > Richelieu I 1619

he inherited the throne during his boyhood, and his uncle John of Gaunt and other nobles dominated the government. The Black Death brought on economic problems, leading to the Peasants' Revolt (1381), which Rich¬ ard quelled with false promises. His enemies among the nobility placed limits on his royal power (1386-89), but he later took revenge on them. He banished John of Gaunt’s son, Henry, and confiscated his vast Lan¬ castrian estates. While Richard was absent in Ireland, Henry invaded England (1399) and seized power as Henry IV. Richard was then forced to abdicate the throne. He was then imprisoned, and sometime in Febru¬ ary 1400 he was executed; by means unknown.

Richard III (b. Oct. 2, 1452, Fotheringhay Castle, Northamptonshire, Eng.—d. Aug. 22, 1485, Bosworth, Leicestershire) Last Yorkist king of England. He was made duke of Gloucester in 1461 after his brother Edward of York had deposed the weak Lancastrian king Henry VI and assumed power as Edward IV. Richard and Edward were driven into exile in 1470 but returned and defeated the Lancastrians in 1471. On Edward’s death (1483), Richard became protector for Edward’s son, the 12-year- old King Edward V, but he usurped the throne and confined Edward and his little brother to the Tower of London, where they were murdered. Henry Tudor (later Henry VII) raised an army against Richard, who was defeated and killed at the Battle of Bosworth Field. Later Tudor histories and William Shakespeare’s play Richard III painted Richard as a mon¬ ster and were gross caricatures motivated by the new dynasty’s need to denigrate its predecessor.

Richard, (Joseph Henri) Maurice (b. Aug. 4,1921, Montreal, Que., Can.—d. May 27,2000, Montreal) Canadian ice-hockey player. He played right wing for the Montreal Canadiens (1942-60) and became the first National Hockey League player to score 50 goals in a regular (50-game) season (1943-44). His nickname, “Rocket,” reflected his speed and aggres¬ sive play. He was also noted for his clutch scoring and fiery temper.

Richards, l(vor) A(rmstrong) (b. Feb. 26, 1893, Sandbach, Cheshire, Eng.—d. Sept. 7, 1979, Cambridge, Cambridgeshire) English critic and poet. While a lecturer at Cambridge, Richards wrote influential works, including Principles of Literary Criticism (1924), in which he intro¬ duced a new way of reading poetry that led to the New Criticism. A student of psychology, he concluded that poetry performs a therapeutic function by coordinating various human impulses into an aesthetic whole. In the 1930s he spent much of his time developing Basic English, a language system of 850 basic words that he believed would promote international understand¬ ing. He taught at Harvard University from 1944.

Richards, (Isaac) Vivian (Alexander) (b. March 7, 1952, St. John’s, Antigua) West Indian professional cricket player. Bom into a sport¬ ing family, Richards appeared in his first Test match for the West Indies against India in 1974, but he came to prominence with a score of 192 while batting against India in his second Test that year. In 1976 Richards scored a record 1,710 runs. His 56-ball century (scoring 100 points on 56 balls bowled) in 1985 is a record in Test cricket. Richards played a vital role in the West Indies’ two World Cup triumphs. He captained the West Indies in 50 Tests with 27 victories and holds the record for never having lost a series as captain. He was selected Wisden Cricketer of the Year in 1977 and was also one of the five cricketers of the century selected by Wisden in 2000. He began coaching the West Indies team upon his retire¬ ment as a player in 1991.

Richardson, Dorothy M(iller) (b. May 17, 1873, Abingdon, Berk¬ shire, Eng.—d. June 17, 1957, Beckenham, Kent) English novelist. From age 17 she engaged in teaching, clerical work, and journalism. For much of her life she worked on her sequence novel Pilgrimage, comprising 13 volumes beginning with Pointed Roofs (1915). The final volume, March Moonlight, was published a decade after her death. A sensitive autobio¬ graphical account of a woman’s developing consciousness, it was a pio¬ neering work in stream-of-consciousness fiction.

Richardson, Henry Handel orig. Ethel Florence Lindesay Richardson (b. Jan. 3, 1870, Melbourne, Austl.—d. March 20, 1946, Fairlight, Sussex, Eng.) Australian-bom English novelist. In 1888 she left Australia to study music in Germany, and she spent the rest of her life abroad, settling in England in 1904 with her husband, J.G. Robertson. Mau¬ rice Guest ( 1908), her antiromantic first novel, concerns a music student’s disastrous love affair. Her masterpiece, The Fortunes of Richard Mahony, 3 vol. (1917-29), combining description of an Australian immigrant’s life and work in the goldfields with a powerful character study, is considered the crowning achievement of modem Australian fiction to that time.

Richardson, Henry Hobson (b. Sept. 29, 1838, Priestley Plantation, La., U.S.—d. April 27, 1886, Brookline, Mass.) U.S. architect. He studied at Harvard University in Cambridge, Mass., and the Ecole des Beaux-Aits in Paris. His designs for Boston’s Brattle Square (1870-72) and Trinity (1872-77) churches won him a national reputation. He designed houses, libraries, suburban railroad stations, educational buildings, and commer¬ cial and civic structures. Instead of the narrow vertical proportions and Gothic features used by his contemporaries, he favoured horizontal lines, simple silhouettes, and large-scale Romanesque or Byzantine-inspired details. The Crane Memorial Library in Quincy, Mass. (1880-82), with its granite base, clerestory windows, tiled gable roof, and cavernous entrance arch, stands among his finest mature works. His Romanesque style had an integrity seldom achieved by his many imitators, and the functionalism of his designs presaged the work of Louis H. Sullivan.

Richardson, John (b. Oct. 4, 1796, probably Fort George, Upper Canada—d. May 12, 1852, New York, N.Y., U.S.) Canadian writer. His experience in the British army in the War of 1812 and later abroad pro¬ vided material for some of his writings. The first Canadian novelist to write in English, he won acclaim with his third novel and only enduring work, Wacousta (1832), a gothic story about the Indian uprising led by Pontiac. His nonfiction includes Personal Memoirs of Major Richardson (1838) and War of 1812 (1842).

Richardson, Sir Ralph (David) (b. Dec. 19, 1902, Cheltenham, Gloucestershire, Eng.—d. Oct. 10, 1983, London) British actor. He began his acting career at age 18 and gained prominence in the 1930s and ’40s at the Old Vic in roles such as Peer Gynt, Petruchio, Falstaff, and Volpone, gaining a reputation as one of the greatest actors of his time. He made his screen debut in 1933 and became known for playing urbane, witty characters and later for eccentric old men. His many films included The Fallen Idol (1948), Doctor Zhivago (1965), and Grey stoke (1984).

Richardson, Samuel (baptized Aug. 19, 1689, Mackworth, near Derby, Derbyshire, Eng.—d. July 4, 1761, Parson’s Green, near London) English novelist. After moving with his family to London at age 10, Rich¬ ardson was apprenticed to a printer before setting up in business for him¬ self in 1721. He soon became quite prosperous. In the 1730s he began to edit and write pamphlets, and he eventually hit on the idea of writing a book using a series of letters on the same subject. His major novels were the epistolary novel Pamela (1740), about a servant who avoids seduction and is rewarded by marriage; and his huge masterpiece, Clarissa, 1 vol. (1747-48), a tragedy with multiple narrators that develops a profoundly suggestive interplay of opposed voices. The History of Sir Charles Gran- dison (1753-54), which blends moral discussion and a comic ending, influenced later writers, especially Jane Austen.

Richardson, Tony orig. Cecil Antonio Richardson (b. June 5, 1928, Shipley, Yorkshire, Eng.—d. Nov. 14, 1991, Los Angeles, Calif., U.S.) British director. With the English Stage Co. he won acclaim with Jofin Osborne’s Look Back in Anger (1956), and he led the company in reinterpreting classic plays and in productions of Eugene Ionesco and Sam¬ uel Beckett. His experimental productions stimulated a renewal of creative vitality on the British stage during the 1950s. He directed The Entertainer (1958) and A Taste of Honey {I960) on Broadway. He and Osborne formed a film company (1958), which pro¬ duced screen versions of Osborne’s plays as well as The Loneliness of the Long Distance Runner (1962) and Tom Jones (1963, Academy Award).

His later films include The Charge of the Light Brigade (1968), Ned Kelly (1970), and Blue Sky (1993). He was married to Vanessa Redgrave; their daughters, Miranda and Joely Rich¬ ardson, are both film actresses.

Richelieu Vri-shs-JuA French \re- sh3-'lyoe\, Armand-Jean du Plessis, cardinal and duke

de (b. Sept. 9, 1585, Richelieu, Poitou, France—d. Dec. 4, 1642, Paris) French statesman and chief minister to Louis XIII. Born to a minor noble family, he was ordained a priest in 1607 and became bishop of Lutjon.

Cardinal de Richelieu, detail of a por¬ trait by Philippe de Champaigne; in the Louvre, Paris.

GIRAUDON/ART RESOURCE, NEW YORK

1620 I Richelieu River ► Ricketts

As the first bishop in France to implement reforms decreed by the Council of Trent, he brought order to a diocese ruined by the Wars of Religion. In 1614 he was elected a deputy of the clergy in the Estates-General, where he was noted as a conciliatory force. He became an adviser to Marie de Medi- cis in 1616 and later councillor to her son, Louis XIII. Named a cardinal in 1622, he served as chief minister from 1624 and became the controlling influence in France’s policies. He established royal absolutism in France by suppressing the political power of the Huguenots and reducing the influ¬ ence of the nobles. In foreign policy, he sought to weaken Habsburg control of Europe and involved France in the Thirty Years' War. Devious and bril¬ liant, he increased the power of the Bourbon dynasty and established orderly government in France. He also founded the Academie Francaise and rebuilt the Sorbonne.

Richelieu River Vri-sho-.liA River, southern Quebec. It is 210 mi (338 km) long and flows north from Lake Champlain to join the St. Lawrence River at Sorel. Explored in 1609 by Samuel de Champlain, it was used by the warring French and English colonists and later by commercial loggers and fishermen. A canal enables shallow-draft vessels to navigate between Montreal and New York City via the St. Lawrence and Richelieu rivers, Lake Champlain, and the Hudson River.

Richler, Mordecai (b. Jan. 27, 1931, Montreal, Que., Can.—d. July 3, 2001, Montreal) Canadian novelist. He grew up in a Jewish working- class neighbourhood in which many of his novels are set. In 1951-52 he lived in Paris, where he was influenced by existentialism; he later lived in England. The Apprenticeship ofDuddy Kravitz (1959) is a bawdy account of a Jewish boy in Montreal and his transformation into a ruthless busi¬ nessman. His later novels include Joshua Then and Now (1980) and Solomon Gursky Was Here (1989). He also wrote children’s books fea¬ turing the character Jacob Two-Two.

Richmond City (pop., 2000: 197,790), capital of Virginia, U.S. Located in the east-central part of the state, on the James River, Richmond was established as a trading post in 1637 and incorporated as a town in 1742. It became the state capital in 1779 and played an important role in the American Revolution. During the American Civil War it was the capital of the Confederate States of America. It was taken by Gen. Ulysses S. Grant in 1865, and much of the business district was burned. It is now a major tobacco market and commercial and government centre; its universities include the University of Richmond (founded 1830) and Virginia Com¬ monwealth University (1838).

Richter Vrik-torN, Conrad (Michael) (b. Oct. 13, 1890, Pine Grove, Pa., U.S.—d. Oct. 30, 1968, Pottsville, Pa.) U.S. short-story writer and novelist. He began as an editor and reporter and founded a juvenile maga¬ zine before moving to New Mexico in 1928. He became fascinated with U.S. history and spent years researching frontier life. He is best known for The Sea of Grass (1936), an epic on the settling of the Southwest, and _ for his trilogy of pioneer life. The Trees (1940), The Fields (1946), and

The Town (1950, Pulitzer Prize). The Waters of Kronos (1960, National Book Award) is an autobiographical novel.

£ Richter Vrik-tari, Curt Paul (b. Feb. 20, 1894, Denver, Colo., U.S.—d.

h] Dec. 21, 1988, Baltimore, Md.) U.S. biologist. He received a Ph.D. from

Johns Hopkins University. He introduced the concept of the biological ■■ clock in a 1927 paper on animals’ internal cycles (see biological rhythm).

He theorized that ancient peoples’ discovery of fire changed their habits, resulting in brain-structure changes that increased their ability to learn and communicate. He helped discover relationships between behaviour and biochemistry governing sleep, stress, and disease onset.

Richter, Gerhard (b. Feb. 9, 1932, Dresden, Ger.) German painter. Beginning in the early 1960s, Richter created paintings that were faithful enlargements of black-and-white photographs, often family snapshots and landscapes; he would continue this pursuit throughout his career. In the 1970s he also created monochromatic paintings, which explored the act of painting at its purest, while by the 1980s he experimented with an expressionistic, gestural style. Notably, Richter never allied himself to one movement—he has been alternatively described as a Pop artist, Minimal¬ ist, and postmodernist. Instead, he has consistently carried out a rigorous, personal exploration of the process of painting.

Richter, Sviatoslav (Teofilovich) (b. March 20, 1915, Zhitomir, Ukraine, Russian Empire—d. Aug. 1, 1997, Moscow, Russia) Ukrainian pianist of German descent. He became accompanist to the Odessa Opera at age 15 and began conducting there at 18. In 1949, two years after he

graduated from the Moscow Conservatory, he won the Stalin Prize. He toured Europe, China, Japan, and the U.S., becoming legendary for the powerful technique and fiery energy in his solo performances. Highly regarded as an accompanist and chamber player as well, he made cel¬ ebrated trio recordings with Mstislav Rostropovich and David Oistrakh.

Richter scale Vrik-toiA Widely used measure of the magnitude of an earthquake, introduced in 1935 by U.S. seismologists Beno Gutenberg (1889-1960) and Charles F. Richter (1900-1985). The scale is logarith¬ mic, so that each increase of one unit represents a 10-fold increase in magnitude (amplitude of seismic waves). The magnitude is then translated into energy released. Earthquakes that are fainter than the ones originally chosen to define magnitude zero are accommodated by using negative numbers. Though the scale has no theoretical upper limit, the most severe earthquakes have not exceeded a scale value of 9. The moment magni¬ tude scale, in use since 1993, is more accurate for large earthquakes; it takes into account the amount of fault slippage, the size of the area rup¬ tured, and the nature of the materials that faulted.

Richthofen \'rikt- I ho-f9n\, Manfred, baron von known as the Red Baron (b. May 2, 1892, Bres¬ lau, Ger.—d. April 21, 1918, Vaux- sur-Somme, France) German World War I ace. Born to a famous and wealthy family, he began his military career in 1912 as a cavalry officer. In 1915 he transferred to the air force and in 1916 took command of a fighter group that came to be known as “Richthofen’s Flying Circus” for its decorated scarlet planes. He had been acclaimed Germany’s greatest aviation ace, credited with shooting down 80 enemy airplanes, before he himself was shot down at age 25.

Ricimer Vri-so-moA orig. Flavius Ricimer (d. Aug. 18, 472) Roman general. The son of a Visigothic prin¬ cess and a Germanic chieftain, he rose high in the Roman army, but he was barred from the imperial throne as a barbarian and instead became a kingmaker in the empire. He defeated the Vandals in Sicily and deposed the emperor Avitus for Majorian (457), who elevated him to consul. In 461 Ricimer deposed and executed Majo¬ rian and appointed Libius Severus as Western emperor. The Eastern emperor later made Anthemius ruler in the West, but Ricimer elevated Oly- brius (472) and killed Anthemius.

Rickenbacker, Eddie orig. Edward Rickenbacher (b. Oct. 8, 1890, Columbus, Ohio, U.S.—d. July 23, 1973, Zurich, Switz.) U.S. World War I ace and industrialist. He developed an early interest in auto¬ mobiles, and by the time the U.S. entered the war in 1917 he was one of the country’s top racing drivers. He began army service as a driver and soon became a fighter pilot. For shooting down 26 enemy airplanes in World War I, he was awarded the Medal of Honor. He later founded and directed his own automobile company, and from 1932 he was an execu¬ tive with several airlines. As president of Eastern Air Lines from 1938 to 1959, he oversaw its growth into a major corporation.

rickets or vitamin D deficiency Disease of infancy and childhood characterized by defective bone growth due to lack of vitamin D. Calcium phosphate is not properly deposited in the bones, which become soft, curved, and stunted. Early symptoms include restlessness, profuse sweat¬ ing, lack of limb and abdominal-muscle tone, soft skull bones, and devel¬ opmental delays. Muscles may cramp and twitch. Without early treatment, effects may include bowlegs, knock-knees, and beadiness where the ribs meet the breastbone. A narrow chest and pelvis can later increase sus¬ ceptibility to lung diseases and impede childbirth. Treatment is with high- dose vitamin D supplementation, sunlight, and a balanced diet. Adding vitamin D to milk has reduced rickets in high-latitude areas where the skin cannot produce enough.

Ricketts, Howard T(aylor) (b. Feb. 9, 1871, Findlay, Ohio, U.S.—d. May 3, 1910, Mexico City, Mex.) U.S. pathologist. He received his medi¬ cal degree from Northwestern University. He discovered the bacterium

Manfred, Freiherr (baron) von Richthofen.

PICTORIAL PARADE

rickettsia ► Riesener I 1621

(named rickettsia) that causes Rocky Mountain spotted fever and epidemic typhus. He demonstrated in 1906 that the former could be transmitted by the bite of a certain tick and identified a bacterium in the blood of infected animals, in the ticks, and in their eggs. He found that epidemic typhus in Mexico was transmitted by a louse and found a related bacterium in the victim’s blood and in the lice. He transmitted the disease to monkeys, which developed immunity. He died of typhus later that year.

rickettsia \ri-'ket-se-3\ Any of the rod-shaped bacteria that make up the family Rickettsiaceae (named for Howard Ricketts). They are rod-shaped or variably spherical, and most are gram-negative (see gram stain). Natu¬ ral parasites of certain arthropods, they can cause serious diseases in humans and other animals, to which they are usually transmitted by a bite from an arthropod carrier. Because certain species can survive consider¬ able drying, rickettsias can also be transmitted when arthropod feces are inhaled or enter the skin through abrasion. Typhus, trench fever, and Rocky Mountain spotted fever are rickettsial infections. The most effective treat¬ ment includes timely and prolonged administration of broad-spectrum antibiotics.

Rickey, Branch (Wesley) (b. Dec. 20, 1881, Stockdale, Ohio, U.S.—d. Dec. 9, 1965, Columbia, Mo.) U.S. baseball executive. Rickey began playing professional baseball while a student at Ohio Wesleyan University. In 1917 he began a long association with the St. Louis Car¬ dinals (president, 1917-19; field manager, 1919-25; general manager, 1925^12). In 1919 he devised the farm system of training ballplayers. He later became president and general manager of the Brooklyn Dodgers (1943-50). Defying strong resistance, in 1945 he broke a long-standing race barrier by hiring the first black player in major league baseball. Jackie Robinson played for the Dodgers’ farm teams for two years before he was brought up to play as an infielder for Brooklyn in 1947. Rickey was later associated with the Pittsburgh Pirates (1950-59).

Rickover, Hyman G(eorge) (b. Jan. 27, 1900, Makov, Russia—d. July 8, 1986, Arlington, Va., U.S.) U.S. naval nuclear engineer. His fam¬ ily immigrated to the U.S. in 1906, and he grew up in Chicago. After graduating from the U.S. Naval Academy, he served on submarines and other ships, then headed the electrical section of the Navy’s Bureau of Ships in World War II. From 1947 he led the Navy’s nuclear-propulsion program; his team developed the first atomic-powered submarine, the USS Nautilus, launched in 1954. He headed research on reactor develop¬ ment for the Atomic Energy Commission and helped develop the coun¬ try’s first full-scale, civilian-use nuclear power plant, at Shippingport, Pa. (1956-57). Promoted to admiral in 1973, he was noted for his outspoken views and his singleminded advocacy of nuclear power.

Rida, Muhammad Rashid See Muhammad Rashid Rida

riddle Deliberately enigmatic or ambiguous question requiring a thoughtful and often witty answer. The riddle is a form of guessing game that has been a part of the folklore of most cultures from ancient times. Western scholars generally recognize two main kinds of riddle: the descriptive riddle, usually describing an animal, person, plant, or object in an intentionally enigmatic manner (thus an egg is “a little white house without door or window”); and the shrewd or witty question. A classical Greek example of the latter type is “What is the strongest of all things?”— “Love: iron is strong, but the blacksmith is stronger, and love can sub¬ due the blacksmith.”

Ride, Sally (Kristen) (b. May 26, 1951, Encino, Calif., U.S.) U.S. astronaut. She received a Ph.D. in physics from Stanford University in 1977 and joined NASA the same year. In 1983 she participated in the sev¬ enth space-shuttle mission, aboard the Challenger, as flight engineer, becoming the first American woman and the third woman internationally (after the Russians Valentina Tereshkova [1963], and Svetlana Savitskaya [1982]) to fly into outer space. She went on to become director of the Cali¬ fornia Space Institute at UC-San Diego in 1989. From 1999 Ride worked on Internet-based projects related to space and pursued her longtime inter¬ est in encouraging young women to study science and mathematics.

Ridgway, Matthew B(unker) (b. March 3, 1895, Fort Monroe, Va., U.S.—d. July 26, 1993, Fox Chapel, near Pittsburgh, Pa.) U.S. army officer. He graduated from West Point and served in staff positions until World War II. In 1942 he commanded an airborne division in the inva¬ sion of Sicily (1943), the first airborne assault in U.S. military history. He led his paratroopers in the Normandy Campaign and commanded airborne operations across Europe. In the Korean War he led the U.S. 8th Army,

rallying UN forces and forcing the Chinese out of South Korea. Promoted to general, he succeeded Douglas MacArthur as Allied commander in the Far East (1951). He later served as supreme commander of NATO forces (1952) and army chief of staff (1953-55).

Riefenstahl Vre-fon-.shtalV, Leni orig. Berta Helene Amalie Riefenstahl (b. Aug. 22, 1902, Berlin, Ger.—d. Sept. 8, 2003, Pocking) German film director and photographer. In the 1920s she was a dancer and actress in German nature films. After forming a production company, she made and starred in the mystical The Blue Light (1932). For Adolf Hitler she directed the propaganda film Triumph of the Will (1935), a documentary glorifying the 1934 Nurnberg rally. She was praised for the technical bril¬ liance of Olympia (1938), her documentary on the 1936 Berlin Olympic Games. Detained by Allied forces after World War II, she was eventually cleared of complicity in Nazi war crimes, but her film career never recov¬ ered, and she worked principally as a photographer thereafter.

Riel \re-'el\, Louis (b. Oct. 23, 1844, St. Boniface, Assiniboia, Can.—d. Nov. 16, 1885, Regina, District of Assinibois, Can.) Canadian leader of the Metis people in western Canada. In 1869 Riel headed a revolt against Cana¬ dian expansion in the west that resulted in the establishment of the province of Manitoba (1870). Intermittent hostilities continued for several years thereafter, and Riel was officially outlawed. In 1885 he led a Metis uprising in Saskatchewan that was crushed by the Canadians. Riel was found guilty of treason and hanged. His death led to ethnic conflicts in Quebec and Ontario and marked the beginning of the nationalist movement.

Riemann \'re-,man\, (Georg Friedrich) Bernhard (b. Sept. 17, 1826, Breselenz, Hanover—d. July 20, 1866, Selasca, Italy) German mathematician. He studied at the Universities of Berlin and Gottingen and later taught principally at Gottingen. His dissertation (1851) was on func¬ tion theory. He became convinced that mathematical theory could link magnetism, light, gravitation, and electricity and suggested field theories, in which the space surrounding electrical charges may be mathematically described. While continuing to develop unifying mathematical themes in the laws of physics, he created Riemannian geometry (or elliptic geometry), which proved essential to Albert Einstein’s model of space-time in relativity theory. Riemann surfaces, Riemann integrals, and Riemann curvature, among other concepts, contributed to the understanding of curves and surfaces, as well as of calculus. With Carl Friedrich Gauss, Riemann helped establish Gottingen’s reputation as a world leader in mathematical research. His work widely influenced geometry and analysis.

Riemannian geometry See elliptic geometry

Riemenschneider Vre-mon- .shni-dorV Tilman (b. c. 1460, Heilgenstadt or Osterode, Domain of the Teutonic Order—d. July 7, 1531, Wurzburg) German sculptor. Son of a mint master, he settled in Wurzburg in 1483 and opened a highly success¬ ful workshop. He was a city council¬ lor (1504-20) and burgomaster (1520-25), but his sympathies with the revolutionaries in the Peasants' War led to a brief imprisonment. His wood and stone sculpture, character¬ ized by sharply folded, flowing drap¬ ery, included monumental tombs and altarpieces as well as independent statues and reliefs, and made him one of the major masters of late Gothic art in Germany.

Rienzo, Cola di See Cola di Rienzo

Riesener \rez-'ner\, Jean-Henri

(b. July 4, 1734, Gladbeck,

Munster—d. Jan. 6, 1806, Paris, Fr.) French cabinetmaker. Son of an usher in the law courts of the elector of Cologne, he joined a workshop in Paris and became its head when his master died. In 1774 he was made royal cabinetmaker and from then on

Jewel casket on a stand, veneered with mahogany, sycamore, and purple- wood, by Riesener, c. 1780; in the Vic¬ toria and Albert Museum, London.

COURTESY OF THE VICTORIA AND ALBERT MUSEUM, LONDON

1622 i Riesman ► Rigveda

was the regular supplier of furniture to Marie-Antoinette. His preferred wood was mahogany; occasionally he used lacquer and mother-of-pearl to enrich his surfaces. His furniture exemplified the Louis XVI style.

Riesman, David (b. Sept. 22, 1909, Philadelphia, Pa., U.S.—d. May 10, 2002, Binghamton, N.Y.) U.S. sociologist. Riesman taught at the uni¬ versities of Buffalo and Chicago before returning to Harvard, his alma mater, to teach (1958-80). He studied primarily the social character of the urban middle class and is noted for The Lonely Crowd (1950), the title of which became a catchphrase for the alienation of the individual in mod¬ em urban society.

Rietveld Vret-.vehA, Gerrit (Thomas) (b. June 24, 1888, Utrecht, Neth.—d. June 25, 1964, Utrecht) Dutch architect and furniture designer. He was an apprentice in his father’s cabinetmaking business (1899-1906) and later studied architecture in Utrecht. In 1918 he created his famous red-and-blue armchair, which, with its emphasis on geometry and use of primary colours, became a symbol of De Stijl. His masterpiece is the Schroeder House in Utrecht (1924), remarkable for its interplay of right- angle forms, planes, and lines, and for its use of primary colours.

Rif Muslim Berber people who live in El-Rif in northern Morocco. Their culture is based on cultivation, herding, and fish processing. They speak a dialect of Berber, but Arabic and Spanish are also widely used. They have traditionally flouted central-government control and have often insti¬ gated uprisings and attempted coups. Led by Abd el-Krim, they declared a short-lived independent republic, the Republic of the Rif (1921-26), which was quashed by a French-Spanish alliance.

Rif, El- \er-'rif\ or Rif Hilly coastal region, northern Morocco. Consti¬ tuting the central and eastern parts of former Spanish Morocco, the hills extend from east of Melilla to Ceuta, both Spanish enclaves. For the greater part of its length, the mountains hug the Mediterranean Sea, leaving only a few narrow coastal valleys suitable for agriculture or urban settlement. The loftier peaks are snowcapped in winter. In the 1920s Berber tribes inhabiting the region rose in revolt under Abd al-Krim to resist Franco- Spanish occupation.

rifle Firearm whose barrel is rifled (i.e., has spiral grooves cut inside it to give a spin to the projectile). Though usually applied to a weapon fired from the shoulder, the name can also refer to a rifled cannon. Rifled fire¬ arms date to at least the 15th century, when it was discovered that impart¬ ing a spin to the bullet improved its range and accuracy. The earliest muzzle-loading rifles were more difficult to load than smoothbore mus¬ kets, but the invention of metallic cartridges made possible the develop¬ ment of breech-loading mechanisms. Bolt-action rifles, which use a manually operated cylinder to drive the cartridge into the rifle’s chamber, are the most common type for hunting. See also assault rifle.

rift valley Elongated trough formed by the subsidence of a segment of the Earth’s crust between dip-slip, or normal, faults. Rift valleys are usu¬ ally narrow and long and have a relatively flat floor. The sides drop away steeply in steps and terraces. Rift valleys are found on the continents and along the crests of oceanic ridges. They occur where two plates that make up the Earth’s surface are separating (see plate tectonics). Submarine rift valleys are usually centres of seafloor spreading, where magma wells up from the mantle. The most extensive continental rift valleys are those of the East African Rift System; other notable examples include Russia’s Baikal Rift Valley and Germany’s Rhine Rift Valley.

Rift Valley See Great Rift Valley

Riga Vre-g9\ City (pop., 2000 prelim.: 764,328), capital of Latvia. Riga is situated on both banks of the Western Dvina River, above its mouth on the Gulf of Riga. It was founded as a trading post in 1201 on the site of an ancient Liv settlement and joined the Hanseatic League in 1282. In the Middle Ages it was dominated by the Teutonic Order, and it was fought over by the Poles and Russians in the 16th century. Riga was cap¬ tured by Sweden in 1621 and granted self-government, but it was ceded to Russia in 1721. The city became the capital of an independent Latvia from 1918 to 1940 but was thereafter incorporated into the U.S.S.R. Riga again became the capital of an independent Latvia in 1991. It is a prin¬ cipal Baltic port and a major administrative, cultural, and industrial cen¬ tre. Its medieval remains include a 13th-century church and a 14th-century castle.

Riga, Gulf of Large gulf of the Baltic Sea. Bounded by Latvia and Estonia, it covers about 7,000 sq mi (18,000 sq km). The gulf, icebound

from December to April, has a maximum depth of 177 ft (54 m). The coasts are mostly low and sandy, and several important rivers, including the Western Dvina, reach the sea there. Several ports and resorts, includ¬ ing Riga, line its shores.

Riga, Treaty of (1921) Treaty between Poland and Russia signed in Riga, Latvia, that ended the Russo-Polish War of 1919-20 and set their mutual border. The treaty, which gave Poland parts of Byelorussia (Belarus) and Ukraine, lasted until World War II, after which a new treaty established a new border.

right Portion of the political spectrum associated with conservative political thought. The term derives from the seating arrangement of the French revolutionary parliament (c. 1790s) in which the conservative rep¬ resentatives sat to the presiding officer’s right. In the 19th century, the term applied to conservatives who supported authority, tradition, and property. In the 20th century a divergent, radical form developed that was associated with fascism. See also left.

right-to-work law In the U.S., any state law forbidding various union-security measures, particularly the union shop, under which work¬ ers are required to join a union within a specified time after they begin employment. Supporters of such laws maintain that they are more equi¬ table because they allow a person to choose whether or not to join a labour union. Opponents contend that the name right-to-work law is misleading because such laws do not guarantee employment to anyone. On the con¬ trary, they maintain that such laws tend to reduce workers’ job security by weakening the bargaining power of unions.

right whale Any of five species (genera Balaena, Eubalaena, and Capered) of baleen whales (family Balaenidae) with a stout body and an enormous head. (The name refers to two species considered the “right” whales to hunt because of their value, slowness, and buoyancy after death.) The upper jaw is strongly arched, and the lower lip curves upward along the side, giving the lower jaw a scooplike form. There is no dorsal fin except in the pygmy right whale ( Caperea marginata), a small, seldom-seen whale of the Southern Hemisphere. The bowhead whale (.Balaena mysticetus), inhabiting Arctic and northern temperate waters, is black, with a white chin, throat, and sometimes underparts. It grows to about 65 ft (20 m). The northern right whale (E. glacialis) grows to 60 ft (18 m). Similar to the bowhead but with a smaller, less strongly arched head, it may also have a “bonnet,” a horny growth infested with parasites, on its snout. Both species have been protected since 1946.

Southern right whale [Eubalaena australis).

ILLUSTRATION BY LARRY FOSTER

rights of the accused See rights of the accused

Rigveda or Rgveda \rig-'va-d9\ Oldest religious scripture in the world and most revered of the Vedas, completed by the 12th century bc. Con¬ sisting of more than 1,000 hymns addressed to devas (gods), it reflects a polytheism that is mainly concerned with the propitiation of divinities asso¬ ciated with the sky and the atmosphere. It makes reference to such ritu¬ als as marriage and funeral rites, which differ little from those practiced today in Hinduism. It is the source of much Indian thought, and many consider its study essential to understanding India.

Riis ► Ringgold I 1623

Riis Vres\, Jacob A(ugust) (b. May 3, 1849, Ribe, Den.—d. May 26, 1914, Barre, Mass., U.S.) U.S. journalist and social reformer. He immi¬ grated to the U.S. at 21 and became a police reporter for the New York Tribune (1877-88) and the New York Evening Sun (1888-99). He publi¬ cized the deplorable living conditions in the slums of New York’s Lower East Side, photographing the rooms and hallways of tenements. He com¬ piled his findings in How the Other Half Lives (1890), a book that stirred the nation’s conscience and spurred the state’s first significant legislation to improve tenements.

Rijn, Rembrandt van See Rembrandt van Rijn

Rikken Seiyukai \'rik- I en-'sa-yu- I kI\ English "Friends of Consti¬ tutional Government" Dominant Japanese political party from its inception in 1900 until 1940. Founded by ho Hirobumi, it initially stood for increased parliamentary participation in government. It was supported by the landlord class and zaibatsu business interests, and was generally more conservative than its chief rival, the Democratic Party (Minseito).

Riley, James Whitcomb (b. Oct. 7, 1849, Greenfield, Ind., U.S.—d. July 22, 1916, Indianapolis, Ind.) U.S. poet. He came into touch with the populace of rural Indiana through his early work experiences. His verse contributions to the Indianapolis Daily Journal, written in Hoosier dia¬ lect ostensibly by a farmer, established his reputation as “the poet of the common people.” His best-known poems include “When the Frost Is on the Punkin” and “The Raggedy Man.” Among his many collections are The Old Swimmin’ Hole (1883), Pipes o’ Pan at Zekesbury (1888), and Home Folks (1900).

rilievo See relief

Rilke Vril-koV, Rainer Maria orig. Rene Maria Rilke (b. Dec. 4, 1875, Prague, Bohemia, Austria-Hungary—d. Dec. 29, 1926, Valmont, Switz.) Austro-German poet. After an unhappy childhood and an ill- planned preparatory education, Rilke began a life of wandering that took him across Europe. His visits to Russia inspired his first serious work, the long poem cycle The Book of Hours (1905). For 12 years beginning in 1902 his geographic centre was Paris, where he researched a book on Auguste Rodin, associated with the great sculptor, and developed a new style of lyrical poetry that attempted to capture the plastic essence of a physical object; the results were New Poems (1907-08) and its prose counterpart, the novel The Notebook of Malte Laurids Brigge (1910). After 13 years of writing very little because of writer’s block and depres¬ sion, in 1922 he finally completed the 10 poems of the Duino Elegies (1923), a profound meditation on the paradoxes of human existence and one of the century’s poetic masterpieces. Unexpectedly and with aston¬ ishing speed, he then composed Sonnets to Orpheus (1923), a superb 55-poem cycle inspired by the death of a young girl, which continues the Elegies’ meditations on death, transcendence, and poetry. The two works brought him international fame.

Rimbaud \ra n -'bo\, (Jean-Nicolas-) Arthur (b. Oct. 20, 1854, Charleville, France—d. Nov. 10,

1891, Marseille) French poet and adventurer. The provincial son of an army captain, he had begun by age 16 to write violent, blasphemous poems, and he formulated an aes¬ thetic doctrine stating that a poet must become a seer, break down the restraints and controls on personal¬ ity, and thus become the instrument for the voice of the eternal. He was invited to Paris by Paul Verlaine, with whom he had a homosexual relation¬ ship and engaged in a wild and dis¬ sipated life. The Drunken Boat (written 1871), perhaps his finest poem, displays his astonishing ver¬ bal virtuosity and a daring choice of images and metaphors. In Les Illu¬ minations (written 1872-74), a col¬ lection of mainly prose poems, he tried to abolish the distinction between reality and hallucination. A Season in Hell (1873), which alter¬ nates prose passages with dazzling lyrics, became his farewell to poetry

at age 19. After they had a falling-out, Verlaine shot and wounded Rim¬ baud; afterward their final meeting ended in a violent quarrel. Rimbaud abandoned literature and from 1875 led an international vagabond life as a merchant and trader, mainly in Ethiopia; he died at age 37 after his leg was amputated. The Dionysian power of his verse and his liberation of language from the constraints of form greatly influenced the Symbolist movement and 20th-century poetry.

Rimsky-Korsakov, Nikolay (Andreyevich) (b. March 18,1844, Tikhvin, near Novgorod, Russia—d. June 21, 1908, Lyubensk) Russian composer. While at St. Petersburg’s College of Naval Cadets, he met other composers; Mily Balakirev took a special interest in him, and from 1867 he was included among the group of nationalist composers known as The Five. Returning from his first cruise as a midshipman in 1865, he com¬ pleted his first symphony. In 1873 he left the naval service and assumed charge of military bands as inspector and conductor. As the de facto edi¬ tor and head of an enterprise dedicated to publishing music by Russian composers, he edited several posthumous works of Aleksandr Borodin and Modest Mussorgsky. He wrote many colourful operas, much loved in Rus¬ sia, including Sadko (1896), Mozart and Salieri (1897), The Legend of the Invisible City of Kitezh (1905), and Le Coq d’or (1908); the subjects of most of these are from Russian or Slavic fairy tales, literature, and his¬ tory. Other works include the suite Scheherazade (1888) and the Russian Easter Festival overture. All his works are distinguished by brilliant orchestration. His many students included Aleksandr Glazunov, Sergey Prokofiev, and Igor Stravinsky.

rinderpest Acute, highly contagious viral disease of ruminants (includ¬ ing wild cloven-hoofed ones), common in Africa, the Indian subcontinent, and the Middle East. The virus spreads by close direct or indirect con¬ tact. It is the most severe infectious disease of cattle, with sudden onset and high mortality; fever and loss of appetite are followed by symptoms including eye and nasal discharge, laboured breathing, and diarrhea; pros¬ tration, coma, and death follow within 6-12 days. Local eradication depends on controlling it in wild animals and eliminating infected domes¬ tic animals; vaccination combined with quarantine is effective.

ring Circular band of gold, silver, or other precious or decorative mate¬ rial usually worn on the finger, but sometimes on the toes, the ears, or the nose. The earliest examples were found in the tombs of ancient Egypt. In addition to being worn as adornment, rings have functioned as symbols of authority, fidelity, or social status. In the early Roman republic, most were made of iron, gold being reserved for persons of high status; but by the 3rd century bc anyone except a slave could wear a gold ring. The Romans are thought to have originated engagement rings, symbolizing a promise of marriage. In the Middle Ages, signet rings were important in religious, legal, and commercial transactions; memorial, posy, and keep¬ sake rings served sentimental purposes; occult rings supposedly had magi¬ cal powers; and poison rings had hollow bezels that could be filled with poison for the purpose of suicide or homicide.

ring In modern algebra, a set of elements with two operations, referred to as “addition” and “multiplication,” that conform to certain conditions. These specify that the set is closed under both operations, the associative law holds for both operations, the commutative law holds for addition, the distributive law holds, there is an additive identity (known as zero), and every element has an additive inverse (see inverse function). The set of integers is a ring. See also field theory.

Ring of Fire Name given to a belt of seismic and volcanic activity roughly surrounding the Pacific Ocean. It includes the Andes Mountains of South America, the coastal regions of western Central America and North America, the Aleutian and Kuril islands, the Kamchatka Peninsula, Japan, Taiwan, eastern Indonesia, the Philippines, New Zealand, and the island arcs of the western Pacific. About three-fourths of all historically recorded active volcanoes have occurred in this belt. See also plate tectonics.

Ringgold, Faith (b. Oct. 8, 1930, New York, N.Y., U.S.) U.S. artist, author, and political activist. She began teaching art in New York’s pub¬ lic schools in the 1950s. In 1963 she began her “American People” series of paintings, which dealt with the civil-rights movement from a female perspective. In the 1970s she became active in promoting feminist art and the racial integration of the New York art world. Her famous “story quilts,” inspired by Tibetan tankas, depict stories set in the context of African American history. She adapted one of her quilts. Tar Beach, as a children’s book and went on to publish other books for children.

Rimbaud, detail from "Un Coin de table," oil painting by Henri Fantin- Latour, 1872; in the Louvre, Paris

GIRAUDON-ART RESOURCE

1624 I Ringling Brothers ► ripple mark

Ringling Brothers Family of U.S. circus owners. After five of the seven brothers formed a song-and- dance troupe (1882), they began to add circus acts to their show. In 1884 they organized their first small circus in their hometown, Baraboo, Wis., and toured the Midwest in circus wagons. In 1890 they began moving their wagons by railway. They acquired smaller circuses from 1900, and in 1907 they bought the Barnum & Bailey Circus, thus becoming the leading U.S. circus. The guiding managers were Charles Ringling (1863-1926) and later John Ringling (1866-1936), whose acquisition of American Circus Corp. in 1929 brought 11 major circuses under Rin¬ gling control. The Ringling Brothers and Barnum & Bailey Circus contin¬ ues to perform, though it passed out of Ringling family hands in 1967.

rings Event in men’s gymnastics in which a pair of rubber-coated metal rings suspended from a ceiling or crossbar are used to perform hanging, swinging, and balancing feats. The rings themselves must remain essen¬ tially stationary. There must be at least two handstands in an exercise, one attained by strength and the other utilizing body swing. Strength move¬ ments on the rings include the iron cross (holding the body vertical with the arms fully stretched sideways) and the lever (hanging with straight arms with the body stretched out horizontally).

ringworm Superficial skin changes caused by certain fungi (see fun¬ gus) that live on the skin, feeding on keratin. Skin responses vary from slight scaling to blistering and marked disruption of the keratin layer (depending on body area and type of fungus), usually in a ring shape. It includes athlete's foot, jock itch, and fungal infections of the body, hands, nails, and scalp. While the last is very contagious, spread of other types depends on susceptibility and predisposing factors (e.g., excessive per¬ spiration). Ringworm is treated with medications applied to the skin or taken orally.

Rio de Janeiro City (pop., 2002 est.: city, 5,937,300; metro, area, 11,121,300) and port, southeastern Brazil. The site was founded by the Por¬ tuguese in the early 16th century and became important in the 18th century as an outlet for mineral exports from gold and diamond mines. Located on one of the largest harbours in the world and known for its scenic views, it was the capital of Brazil from 1822 to 1960, when the national capital was moved to Brasilia. It is the country’s second largest manufacturing centre after Sao Paulo. Major industries include metallurgy and food processing. Noted for its wide streets, public buildings, beaches (see Copacabana), and public parks and gardens, it is a leading tourist and resort centre.

Rio de la Plata See Rio de la Plata

Rio de la Plata, Viceroyalty of the Last of the four viceroyalties that Spain created to govern its New World colonies. Established in 1776 as means of decentralizing rule in the Spanish empire, it controlled an area previously administered by the Viceroyalty of Peru and included what is now Argentina, Uruguay, Paraguay, and Bolivia. Successive viceroys defended the territory against encroachment by Portugal and Britain and helped Buenos Aires become a flourishing outpost of the Spanish empire. Salted meat from the cattle ranches of the interior, exported to meet the demand for cheap food for slaves, brought unprecedented wealth to the colony. In 1810 the Creoles created a provisional junta and sent the vice¬ roy into exile. See also New Granada;New Spain.

Rio de Oro Southern region. Western Sahara. Its principal town, Al-Dakhla (formerly Villa Cisneros), has a small port and must rely on imported drinking water. The narrow inlet of the Atlantic Ocean at Al-Dakhla was called Rio de Oro (“River of Gold”) by the Portuguese because of the trade in gold dust from western Africa that they engaged in there. From the 1880s until 1976 it was ruled by Spain. In 1979 it was occu¬ pied by Morocco. The indigenous inhabitants are Muslim and largely nomadic Berbers.

Rio Grande \ , re-o- , grand\ in Mexico Rio Bravo River, North America. One of the longest rivers of North America, it flows 1,900 mi

(3,000 km) from its sources in the Rocky Mountains of southwestern Colo¬ rado, U.S., to the Gulf of Mexico. It rises high in the San Juan Mountains and flows generally south, passing southeast and forming the entire bor¬ der between Texas and Mexico. The earliest European settlements were along the lower course of the river in the 16th century, but many of the Pueblo Indian settlements of New Mexico date from before the Spanish conquest. During the Spanish period, the middle and upper portions were called the Rio del Norte, and the lower course was called the Rio Bravo. It is a major source of irrigation. At the U.S.-Mexican border, it defines the edge of Big Bend National Park, Texas.

Rio Treaty officially Convention on Biological Diversity Inter¬ national environmental agreement approved at the 1992 Earth Suaamit in Rio de Janeiro. Negotiations began in 1988 under the auspices of the United Nations Environment Program. Its goals are the conservation of the planet’s biodiversity and the fair use of its resources. By the early 21st century, more than 185 governments were party to the agreement.

Riopelle \re-o-'pel\, Jean-Paul (b. Oct. 7, 1923, Montreal, Que., Can.—d. March 12, 2002, Ile-aux-Grues, near Quebec City) Canadian painter and sculptor. He moved to Paris in 1947 and, with Paul-Emile Bor- duas, became associated with the group of Canadian painters known as Les Automatistes, who practiced automatism. His early lyrical, abstract paintings evolved into a denser, more powerful impasto style. He is renowned for his use of various media (including watercolour, ink, oils, crayon, and chalk), and he also produced large collage murals. He achieved international acclaim with the huge triptych Pavane (1954) and is the leading Canadian abstract painter of his generation.