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  • Rokycana, Jan (Bohemian archbishop)

    Jan Rokycana, priest, archbishop, and follower of Jan Hus (1372/73–1415); he was a chief organizer of the papally denounced Hussite Church and a major figure in Bohemian church history. Rokycana went to Prague probably in 1410, assisting and later succeeding Jakoubek of St?íbro as organizer of the

  • Rol-Tanguy, Henri (French military leader)

    Henri Rol-Tanguy, (Henri Tanguy), French World War II Resistance leader (born June 12, 1908, Morlaix, France—died Sept. 8, 2002, Monteaux?, France), commanded the Resistance forces during the Parisian uprising against German occupation; he helped liberate Paris in August 1944 and was one of those w

  • Rolamite (mechanics)

    Rolamite, mechanical roller-band device that functions as an almost frictionless suspension system for rollers; it consists of a flexible metal band formed in an S-shaped loop. In the Figure, rollers A and B are suspended within the loops of the flexible metallic band C, fastened at D and E to the

  • Roland (missile)

    rocket and missile system: Surface-to-air: …SAM systems include the German-designed Roland, an SA-8 equivalent fired from a variety of tracked and wheeled vehicles, and the French Crotale, an SA-6 equivalent that used a combination of radar command guidance and infrared terminal homing. Both systems were widely exported. Less directly comparable to Soviet systems was the…

  • Roland (epic hero)

    Orlando, hero of the Charlemagne epics. Later literature that features the character includes Matteo Maria Boiardo’s Orlando innamorato and Ludovico Ariosto’s Orlando

  • Roland Barthes (work by Barthes)

    French literature: Biography and related arts: …Barthes par Roland Barthes (1975; Roland Barthes), a contradictory, self-critical portrait; and Nathalie Sarraute’s Enfance (1983; Childhood). Genre boundaries blurred: in Barthes’s Fragments d’un discours amoureux (1977; A Lover’s Discourse: Fragments), criticism and self-analysis became fiction and writing became an erotic act.

  • Roland Barthes par Roland Barthes (work by Barthes)

    French literature: Biography and related arts: …Barthes par Roland Barthes (1975; Roland Barthes), a contradictory, self-critical portrait; and Nathalie Sarraute’s Enfance (1983; Childhood). Genre boundaries blurred: in Barthes’s Fragments d’un discours amoureux (1977; A Lover’s Discourse: Fragments), criticism and self-analysis became fiction and writing became an erotic act.

  • Roland de La Platière, Jean-Marie (French scientist)

    Jean-Marie Roland, French industrial scientist who, largely through his wife’s ambition, became a leader of the moderate Girondin faction of bourgeois revolutionaries during the French Revolution. The son of a royal official, Roland became inspector of manufactures in Amiens (1780) and then in Lyon

  • Roland de La Platière, Jeanne-Marie (French politician)

    Jeanne-Marie Roland, wife of Jean-Marie Roland, who directed her husband’s political career during the French Revolution, greatly influencing the policies of the moderate Girondin faction of bourgeois revolutionaries. Jeanne-Marie Phlipon was the daughter of a Paris engraver. Brilliant and

  • Roland Holst-van der Schalk, Henri?tte Goverdina Anna (Dutch poet and socialist)

    Henri?tte Goverdina Anna Roland Holst-van der Schalk, Dutch poet and active Socialist whose work deals with the humanitarian concerns that informed her politics. She was a lawyer’s daughter. In 1896 she married the painter Richard Nicolaas Roland Holst (1868–1938), himself a talented prose writer.

  • Roland the Headless Thompson Gunner (song by Zevon)

    Warren Zevon: …the geopolitically inspired songs “Roland the Headless Thompson Gunner” and “Lawyers, Guns and Money.”

  • Roland von Berlin, Der (work by Alexis)

    Willibald Alexis: Der Roland von Berlin (1840) portrays the struggle for power in the 15th century between the municipal authorities of Berlin-K?lln and the ruler of Brandenburg; Der falsche Woldemar (1842; “The False Woldemar”) recounts the rise and fall of a 14th-century pretender. In the first part…

  • Roland, Der (opera by Leoncavallo)

    Ruggero Leoncavallo: … (1900) was more successful, but Der Roland (1904), commissioned by Wilhelm II to glorify the Hohenzollerns, was a failure. A number of later works achieved passing success. For most of his operas Leoncavallo was his own librettist and showed a distinct literary ability and a flair for theatrical effect.

  • Roland, Gilbert (American actor)

    Gilbert Roland, (LUIS ANTONIO DáMASO DE ALONSO), U.S. actor (born Dec. 11, 1905, Ciudad Juárez, Mexico—died May 15, 1994, Beverly Hills, Calif.), specialized in portraying charismatic and dashing Latin lovers, most notably in the 1927 silent-film classic Camille opposite Norma Talmadge, but he w

  • Roland, Jean-Marie (French scientist)

    Jean-Marie Roland, French industrial scientist who, largely through his wife’s ambition, became a leader of the moderate Girondin faction of bourgeois revolutionaries during the French Revolution. The son of a royal official, Roland became inspector of manufactures in Amiens (1780) and then in Lyon

  • Roland, Jeanne-Marie (French politician)

    Jeanne-Marie Roland, wife of Jean-Marie Roland, who directed her husband’s political career during the French Revolution, greatly influencing the policies of the moderate Girondin faction of bourgeois revolutionaries. Jeanne-Marie Phlipon was the daughter of a Paris engraver. Brilliant and

  • Roland, La Chanson de (French epic poem)

    La Chanson de Roland, Old French epic poem that is probably the earliest (c. 1100) chanson de geste and is considered the masterpiece of the genre. The poem’s probable author was a Norman poet, Turold, whose name is introduced in its last line. The poem takes the historical Battle of Roncesvalles

  • Rolando, fissure of

    brain: Two major furrows—the central sulcus and the lateral sulcus—divide each cerebral hemisphere into four sections: the frontal, parietal, temporal, and occipital lobes. The central sulcus, also known as the fissure of Rolando, also separates the cortical motor area (which is anterior to the fissure) from the cortical sensory…

  • Rolando, sulcus of

    brain: Two major furrows—the central sulcus and the lateral sulcus—divide each cerebral hemisphere into four sections: the frontal, parietal, temporal, and occipital lobes. The central sulcus, also known as the fissure of Rolando, also separates the cortical motor area (which is anterior to the fissure) from the cortical sensory…

  • Rold Forest (forest, Denmark)

    Himmerland: …blue anemones grow in the Rold Forest, the remnant of a spruce forest that once covered most of the region. North of Rold Forest the heather-covered Rebild Hills, bought by Danish Americans in 1911 and donated to Denmark (1912) as a national park, are the site of annual Danish-American July…

  • Roldán, Francisco (Spanish colonial mayor)

    Christopher Columbus: The second and third voyages: …the mayor of La Isabela, Francisco Roldán, had led to appeals to the Spanish court, and, even as Columbus attempted to restore order (partly by hangings), the Spanish chief justice, Francisco de Bobadilla, was on his way to the colony with a royal commission to investigate the complaints. It is…

  • Roldán, Luisa (Spanish sculptor)

    National Museum of History: …Child,” attributed to the artist Luisa Roldán, who was Spanish royal sculptor to King Charles II.

  • Roldán, Pedro (Spanish sculptor)

    Pedro Roldán, Spanish sculptor, painter, and architect, best remembered for his work on the main altarpiece at La Caridad, Sevilla (Seville), designed by Simón de Pineda and polychromed by Juan Valdés Leal. After studying in Granada with Alonso de Mena, the father of the famous sculptor Pedro de

  • Roldós Aguilera, Jaime (president of Ecuador)

    Jaime Roldós Aguilera, lawyer elected president of Ecuador in 1979. After graduating from the University of Guayaquil and its law school, Roldós joined the faculty of the Vicente Rocafuerte University in Guayaquil. In 1962 he married Marta Bucaram, a niece of Assad Bucaram, the leader of the

  • Rolduc (abbey, Kerkrade, Netherlands)

    Kerkrade: The former abbey of Rolduc (1104) has a notable Romanesque church; its courtyard buildings now serve as a boys’ school. A natural history and mining museum is housed in Oud Ehrenstein Castle. International music contests are held periodically in the Europaplein Park. Kerkrade metropolitan area is contiguous with Heerlen…

  • role (sociology)

    Role, in sociology, the behaviour expected of an individual who occupies a given social position or status. A role is a comprehensive pattern of behaviour that is socially recognized, providing a means of identifying and placing an individual in a society. It also serves as a strategy for coping

  • role model (sociology)

    propaganda: Selection and presentation of symbols: …in, they include among their images a variety of symbols associated with parents and parent surrogates. The child lives on in every adult, eternally seeking a loving father and mother. Hence the appeal of such familistic symbolisms as “the fatherland,” “the mother country,” “the Mother Church,” “the Holy Father,” “Mother…

  • Role of Defensive Pursuit, The (book by Chennault)

    Claire L. Chennault: …also wrote an aviation textbook, The Role of Defensive Pursuit (1935), that detailed new fighter tactics. His belief that bombers were vulnerable to attack by fighter planes, however, put him at odds with his superiors. Partial deafness and increasing disagreements with other air corps officers led him to retire in…

  • Role of Monetary Policy, The (work by Friedman)

    economics: Macroeconomics: …appeared, and in 1968 “The Role of Monetary Policy,” first delivered as Milton Friedman’s presidential address to the American Economic Association, introduced the notorious concept of “the natural rate of unemployment” (the minimum rate of unemployment that will prevent businesses from continually raising prices). Friedman’s paper defined the essence…

  • role of Nigerian women

    From precolonial times to the early 21st century, the role and status of women in Nigeria have continuously evolved. However, the image of a helpless, oppressed, and marginalized group has undermined their proper study, and little recognition has been granted to the various integral functions that

  • role playing (sociology)

    employee training: Another new technique is role playing. Members of the training staff create a situation by playacting, and the trainees either comment on what is taking place or participate in the attempt to find a solution, or they perform functions or services in conditions that simulate their working environment. Attention…

  • role-playing game

    Ernest Gary Gygax: …created the world’s first fantasy role-playing game (RPG), Dungeons & Dragons (D&D), and ultimately paved the way for modern electronic RPGs.

  • role-playing video game (electronic game genre)

    Role-playing video game, electronic game genre in which players advance through a story quest, and often many side quests, for which their character or party of characters gain experience that improves various attributes and abilities. The genre is almost entirely rooted in TSR, Inc.’s Dungeons &

  • Rolex (Swiss manufacturer)

    Rolex, Swiss manufacturer of rugged but luxurious watches. Company headquarters are in Geneva. Founder Hans Wilsdorf was born in Germany but moved to Switzerland when he was a young man. There he found work at a watch-exporting company in La Chaux-de-Fonds, one of the centres of the Swiss

  • Rolex Watch Co. Ltd. (Swiss manufacturer)

    Rolex, Swiss manufacturer of rugged but luxurious watches. Company headquarters are in Geneva. Founder Hans Wilsdorf was born in Germany but moved to Switzerland when he was a young man. There he found work at a watch-exporting company in La Chaux-de-Fonds, one of the centres of the Swiss

  • Rolf (Swiss circus trainer)

    Rodolphe Knie, Swiss elephant trainer who was director of the highly respected family-owned Swiss National Circus for 50 years (b. Nov. 23, 1921--d. Aug. 18,

  • Rolf (duke of Normandy)

    Rollo, Scandinavian rover who founded the duchy of Normandy. According to later Scandinavian sagas, Rollo, making himself independent of King Harald I of Norway, sailed off to raid Scotland, England, Flanders, and France on pirating expeditions. Early in the 10th century, Rollo’s Danish army

  • Rolf Krage (work by Ewald)

    Johannes Ewald: …resulted in the historical drama Rolf Krage (1770), taken from an old Danish legend that was recorded by the medieval historian Saxo Grammaticus.

  • Rolf Nevanlinna Prize (mathematics award)

    Fields Medal: A related award, the Rolf Nevanlinna Prize, has also been presented at each International Congress of Mathematicians since 1982. It is awarded to one young mathematician for work dealing with the mathematical aspects of information science.

  • Rolfe Johnson, Anthony (British singer)

    Anthony Rolfe Johnson, British tenor (born Nov. 5, 1940, Tackley, Oxfordshire, Eng.—died July 21, 2010, London, Eng.), employed his light, flexible tenor voice and strong acting skills in operas ranging from Handel’s Semele to Mozart’s Idomeneo, which served as his debut role at New York City’s

  • Rolfe, Frederick William (English author)

    Frederick William Rolfe, English author and eccentric, best known for his autobiographical fantasy Hadrian the Seventh. He provides the curious example of an artist rescued from obscurity by his biographer; many years after Rolfe’s death A.J.A. Symons wrote a colourful biographical fantasy, The

  • Rolfe, John (British colonial official)

    John Rolfe, Virginia planter and colonial official who was the husband of Pocahontas, daughter of the Indian chief Powhatan. John Rolfe sailed for Virginia in 1609, but a shipwreck in the Bermudas delayed his arrival until the following year. About 1612 he began to experiment with growing tobacco.

  • Rolie, Gregg (American musician)

    Santana: …1947, Autlán de Navarro, Mexico), Gregg Rolie (b. June 17, 1947, Seattle, Washington, U.S.), David Brown (b. February 15, 1947, New York, U.S.—d. September 4, 2000), Mike Carabello (b. November 18, 1947, San Francisco, California, U.S.), José (“Chepito”) Areas (b. July 25, 1946, León, Nicaragua), and Mike Shrieve (b. July…

  • Rolin, Dominique (Belgian author)

    Dominique Rolin, Belgian novelist noted for embracing new narrative techniques. Author of more than 30 books in 50 years, Rolin produced a body of fiction that centres on the themes of birth, death, family, and physical dislocation. Between 1942 and 1946, influenced by German Romanticism, Rolin

  • Rolin, Nicolas (chancellor of Burgundy)

    Rogier van der Weyden: …Burgundy, and his powerful chancellor, Nicolas Rolin. Rogier may well have also been influenced by the writings of Thomas à Kempis, the most popular theologian of the era, whose “practical mysticism,” like Rogier’s painting, stressed empathetic response to episodes from the lives of Mary, Christ, and the saints.

  • roll (food)

    baking: Breads and rolls: Most of the bakery foods consumed throughout the world are breads and rolls made from yeast-leavened doughs. The yeast-fermentation process leads to the development of desirable flavour and texture, and such products are nutritionally superior to products of the equivalent chemically leavened doughs, since…

  • roll (motion)

    ship: Ship motions in response to the sea: …freedom, the other four being roll (rotation about a longitudinal axis), pitch (rotation about a transverse axis), heave (vertical motion), and surge (longitudinal motion superimposed on the steady propulsive motion). All six are unwanted except in the special circumstance where yaw is necessary in changing course.

  • Roll Call (American newspaper)

    Roll Call, American newspaper covering the U.S. Congress. It was founded in Washington, D.C., in 1955 by Sid Yudain, a former congressional press secretary. Roll Call was initially a weekly newspaper but eventually was published Monday through Thursday during weeks in which Congress was in session.

  • roll crusher

    mineral processing: Crushing/grinding: …crushing and grinding, is the roll crusher. This consists essentially of two cylinders that are mounted on horizontal shafts and driven in opposite directions. The cylinders are pressed together under high pressure, so that comminution takes place in the material bed between them.

  • roll film (photography)

    technology of photography: Roll film: The term roll film is usually reserved for film wound up on a spool with an interleaving light-tight backing paper to protect the wound-up film. The spool is loaded into the camera in daylight, the backing paper leader threaded to a second spool,…

  • roll forging (technology)

    forging: In roll forging, the metal blank is run through matched rotating rolls with impressions sunk in their surfaces. Impact forging is essentially hammer forging in which both dies are moved horizontally, converging on the workpiece. Counterblow forging is similar, except that the dies converge vertically. A…

  • roll molding (architecture)

    molding: Single curved: (6) A roll, or bowtell, molding is convex, approximating three-quarters of a circle. (7) An astragal is a small torus. (8) An apophyge molding is a small, exaggerated cavetto.

  • Roll with Me, Henry (song by James)

    Etta James: …but it was retitled “The Wallflower” because of its perceived sexual connotation; the lyrics and title were changed to “Dance with Me, Henry” for singer Georgia Gibbs’s 1955 rendition, which reached number one on the charts. After signing (1960) with Chess Records, James became its first major female star,…

  • roll-film camera (photography)

    technology of photography: The medium-size hand camera: This type of camera takes sheet film (typical formats of from 212 × 312 inches to 4 × 5 inches), roll film, or 70-mm film in interchangeable magazines; it has interchangeable lenses and may have a coupled rangefinder. Special types use wide-angle…

  • roll-front deposit (mineralogy)

    mineral deposit: Roll-front deposits: Uranium occurs in two valence states, U4+ and U6+. Weathering of rocks converts uranium into the +6 state, in which state it forms the uranyl ion (UO2)2+. Uranyl compounds tend to be soluble in groundwater, whereas U4+ compounds are not. So long as…

  • roll-front uranium deposit (mineralogy)

    mineral deposit: Roll-front deposits: Uranium occurs in two valence states, U4+ and U6+. Weathering of rocks converts uranium into the +6 state, in which state it forms the uranyl ion (UO2)2+. Uranyl compounds tend to be soluble in groundwater, whereas U4+ compounds are not. So long as…

  • roll-on, roll-off ship (naval technology)

    harbours and sea works: Roll-on, roll-off facilities: An enormous increase in the use of the roll-on, roll-off technique of loading and unloading developed in the late 1960s. The principle of embarking whole vehicles under their own power was not new. The report of Hannibal ferrying his elephants over the…

  • Rolla (Missouri, United States)

    Rolla, city, seat (1861) of Phelps county, south-central Missouri, U.S. It is located in the Ozark Mountains, near the Gasconade River and units of the Mark Twain National Forest (headquartered at Rolla). Originating about 1856 as a construction site for the St. Louis–San Francisco Railway, it

  • Rolland, Romain (French writer)

    Romain Rolland, French novelist, dramatist, and essayist, an idealist who was deeply involved with pacifism, the fight against fascism, the search for world peace, and the analysis of artistic genius. He was awarded the Nobel Prize for Literature in 1915. At age 14, Rolland went to Paris to study

  • Rolle’s theorem (mathematics)

    Rolle’s theorem, in analysis, special case of the mean-value theorem of differential calculus. Rolle’s theorem states that if a function f is continuous on the closed interval [a, b] and differentiable on the open interval (a, b) such that f(a) = f(b), then f′(x) = 0 for some x with a ≤ x ≤ b. In

  • Rolle, Andrew (American historian)

    Los Angeles: The contemporary city: As historian Andrew Rolle wrote,

  • Rolle, Esther (American actress)

    Esther Rolle, American actress whose portrayal of Florida Evans in the 1970s television series "Maude" and "Good Times" brought her national recognition; long a campaigner against racial stereotyping, she temporarily left the cast of "Good Times" to protest the poor example set by her TV son in the

  • Rolle, Michel (French mathematician)

    Rolle's theorem: …1691 by the French mathematician Michel Rolle, though it was stated without a modern formal proof in the 12th century by the Indian mathematician Bhaskara II. Other than being useful in proving the mean-value theorem, Rolle’s theorem is seldom used, since it establishes only the existence of a solution and…

  • Rolle, Richard (British mystic)

    Richard Rolle, English mystic and author of mystical and ascetic tracts. Rolle attended the University of Oxford but, dissatisfied with the subjects of study and the disputatiousness there, left without a degree. He established himself as a hermit on the estate of John Dalton of Pickering, but he

  • rolled oats (food)

    oats: Rolled oats, flattened kernels with the hulls removed, are used mostly for oatmeal; other breakfast foods are made from the groats, which are unflattened kernels with husks removed. Oat flour is not generally considered suitable for bread but is used to make cookies and puddings.…

  • Rollefson, Gary (American anthropologist)

    ?Ain Ghazal: …mostly led by American anthropologist Gary Rollefson. In 2004 the World Monuments Fund placed ?Ain Ghazal on its watch list of endangered cultural heritage sites, citing urban development as the greatest threat to the site’s preservation.

  • Rolleiflex (camera)

    Rolleiflex, twin-lens reflex roll-film camera introduced by the German firm Franke & Heidecke in 1928. It had two lenses of identical focal length—one transmitting the image to the film and the other functioning as a viewfinder and part of the focusing mechanism. Twelve exposures, 6 cm square

  • Rollende Landstrasse (technology)

    railroad: Operations: …technology called “Rolling Highway” (Rollende Landstrasse), because it employs low-floor cars that, coupled into a train, form an uninterrupted drive-on, drive-off roadway for highway trucks or tractor-trailer rigs. Rolling Highway cars are carried on four- or six-axle trucks with wheels of only 36-cm (14-inch) diameter so as to lower…

  • roller (bird)

    Roller, any of about 12 species of Old World birds constituting the family Coraciidae (order Coraciiformes), named for the dives and somersaults they perform during the display flights in courtship. The family is sometimes considered to include the ground rollers and cuckoo rollers. Rollers inhabit

  • roller (farm machine)

    Roller, farm implement used to break up lumps left by harrows and to compact the soil, eliminating large air spaces. The plain roller is often used to compact grassland damaged by winter heaving. Corrugated rollers, single or tandem, crush clods and firm the soil after plowing. A type usually

  • roller bearing (device)

    Roller bearing, one of the two members of the class of rolling, or so-called antifriction, bearings (the other member of the class is the ball bearing). Like a ball bearing, a roller bearing has two grooved tracks, or races, but the balls are replaced by rollers. The rollers may be cylinders or

  • roller chain (chain drive)

    chain: A roller chain is a development of the block chain in which the block is replaced by two side plates, a pair of bushings, and rollers. (See Figure 3.) This type of chain is used on bicycles and is adaptable to many other needs, from small-strand…

  • roller coaster (ride)

    Roller coaster, elevated railway with steep inclines and descents that carries a train of passengers through sharp curves and sudden changes of speed and direction for a brief thrill ride. Found mostly in amusement parks as a continuous loop, it is a popular leisure activity. On a traditional

  • Roller Derby (sport)

    roller-skating: Roller sports: Roller Derby was one of the first roller sports to succeed on the professional level. The sport originated in Chicago in 1935 as an endurance competition between male-female couples. The teams would circle a banked rink for 57,000 laps, a total distance that was said…

  • roller dryer (food processing)

    dairy product: Drum dryers: The simplest and least expensive is the drum, or roller, dryer. It consists of two large steel cylinders that turn toward each other and are heated from the inside by steam. The concentrated product is applied to the hot drum in a thin…

  • roller hockey (sport)

    roller-skating: Roller sports: The first recorded game of roller hockey took place in London in 1878. Speed roller-skating events began in the 1890s and were popular through the first quarter of the 20th century. Major speed roller-skating events for men, women, and relay teams involve racing counterclockwise around an oval track or on…

  • roller link (chain drive device)

    chain: …assembled from pin links and roller links. A pin link consists of the two side plates connected by two tightly fitted pins. A roller link consists of two side plates connected by two tightly fitted bushings on which hardened steel rollers are free to rotate. When assembled, the pins are…

  • roller mill (processing technology)

    sugar: Juice extraction: …the crusher, a set of roller mills in which the cane cells are crushed and juice extracted. As the crushed cane proceeds through a series of up to eight four-roll mills, it is forced against a countercurrent of water known as water of maceration or imbibition. Streams of juice extracted…

  • roller press (machine tool)

    coin: Early modern minting: At the same time the roller press was under development in Germany. Initially, the die designs were engraved or punched into the curved surfaces of two rollers that were geared together so that the whole fillet (rather than single blanks) could be fed between them and emerge impressed. This method…

  • roller printing (textile industry)

    Roller printing, method of applying a coloured pattern to cloth, invented by Thomas Bell of Scotland in 1783. A separate dye paste for each colour is applied to the fabric from a metal roller that is intaglio engraved according to the design. The technique can be used with almost any textile

  • roller pump (surgical instrument)

    Michael DeBakey: …1932 DeBakey devised the “roller pump,” an essential component of the heart-lung machine that permitted open-heart surgery. He also developed an efficient method of correcting aortic aneurysms by grafting frozen blood vessels to replace diseased vessels. By 1953 DeBakey had developed a technique of using plastic tubing (Dacron) instead…

  • roller-bit cutter (machine)

    tunnels and underground excavations: Preserving rock strength: …the hard-faced rolling disks, and roller-bit cutters using bits initially developed for fast drilling of oil wells. As later entrants in the field, European manufacturers have generally tried a different approach—milling-type cutters that mill or plane away part of the rock, then shear off undercut areas. Attention is also focusing…

  • roller-packer (farm machine)

    roller: A type usually called a roller-packer or land presser has heavy, wedge-shaped wheels about 3 feet (1 m) in diameter and is used in dry seasons to compress the soil after plowing.

  • roller-skating (sport)

    Roller-skating, recreational and competitive sport in which the participants use special shoes fitted with small wheels to move about on rinks or paved surfaces. Roller-skating sports include speed skating, hockey, figure skating, and dancing competitions similar to the ice-skating sports, as well

  • Rollerball (film by Jewison [1975])

    Norman Jewison: …then helmed the futuristic dystopia Rollerball (1975); the union saga F.I.S.T. (1978), starring Sylvester Stallone; and the legal drama ...And Justice for All (1979), with Al Pacino. He again examined racial prejudice in A Soldier’s Story (1984), about the murder of an African American army sergeant. Later efforts included

  • Rollerblade skating (recreation)

    roller-skating: Development of the roller skate: …of a new generation of in-line roller skates by hockey-playing brothers Scott and Brennan Olson, the founders of Rollerblade, Inc. They developed in-line skates with four wheels that extended the full length of the boot, giving the skater greater maneuverability (compared with previous in-line skates) and much more speed. The…

  • rollerblading (recreation)

    roller-skating: Development of the roller skate: …of a new generation of in-line roller skates by hockey-playing brothers Scott and Brennan Olson, the founders of Rollerblade, Inc. They developed in-line skates with four wheels that extended the full length of the boot, giving the skater greater maneuverability (compared with previous in-line skates) and much more speed. The…

  • rollerlike bird (bird)

    Coraciiform, (order Coraciiformes), any member of an order made up of 10 families of birds that include the kingfishers, todies, motmots, bee-eaters, rollers, hoopoes, and hornbills. Among the members of the order that have attracted special attention are certain kingfishers that plunge headfirst

  • Rolleston, William (New Zealand minister)

    New Zealand: Fluctuation of the economy: William Rolleston, minister of lands in the early 1880s, first proposed that the state help men to become small farmers as state tenants; John (later Sir John) McKenzie and the Liberal government applied that remedy with vigour in the 1890s. But closer settlement and intensive…

  • Rollet, Paul (military official)

    French Foreign Legion: History: The legion’s first inspector general, Paul Rollet, who had commanded the RMLE in the last year of the war, sought to secure the legion’s place in the public imagination and in the French army by reviving pre-1914 “traditions,” beginning with the uniform. Legionnaires in the 19th century, particularly those in…

  • Rolli, Paolo Antonio (Italian author)

    Paolo Antonio Rolli, librettist, poet, and translator who, as Italian master to the English royal household, helped to Italianize 18th-century English taste. The son of an architect, Rolli studied with the major Italian literary critic of the day, Gian Vincenzo Gravina. In 1715 he went to England

  • rolling (tea industry)

    tea: Rolling: At this stage, the withered leaf is distorted, acquiring the distinctive twist of the finished tea leaf, and leaf cells are burst, resulting in the mixing of enzymes with polyphenols.

  • rolling (technology)

    Rolling, in technology, the principal method of forming molten metals, glass, or other substances into shapes that are small in cross-section in comparison with their length, such as bars, sheets, rods, rails, girders, and wires. Rolling is the most widely used method of shaping metals and is

  • rolling bearing

    bearing: …rollers; these are known as rolling bearings. In the illustration, the inner race turns with the shaft.

  • rolling friction (physics)

    friction: Rolling friction occurs when a wheel, ball, or cylinder rolls freely over a surface, as in ball and roller bearings. The main source of friction in rolling appears to be dissipation of energy involved in deformation of the objects. If a hard ball is rolling…

  • rolling gate (engineering)

    dam: Gates: …vertical-lift gate that, sliding or rolling against guides, can be raised to allow water to flow underneath. Radial, or tainter, gates are similar in principle but are curved in vertical section to better resist water pressure. Tilting gates consist of flaps held by hinges along their lower edges that permit…

  • Rolling Highway (technology)

    railroad: Operations: …technology called “Rolling Highway” (Rollende Landstrasse), because it employs low-floor cars that, coupled into a train, form an uninterrupted drive-on, drive-off roadway for highway trucks or tractor-trailer rigs. Rolling Highway cars are carried on four- or six-axle trucks with wheels of only 36-cm (14-inch) diameter so as to lower…

  • Rolling in the Deep (recording by Adele)

    Adele: …earthy gospel- and disco-inflected “Rolling in the Deep” to the affecting breakup ballad “Someone like You.” Both songs hit number one in multiple countries, and, despite a vocal-cord ailment that forced Adele to cancel numerous tour dates in 2011, the album became the biggest-selling release of the year in…

  • rolling magazine (military technology)

    logistics: Logistic systems before 1850: …its smaller, mobile version, the rolling magazine, which carried a few days’ supply for an army on the march. Secure lines of communication became vital, and whole armies were deployed to protect them. The increasing size of armies and of artillery and baggage trains placed heavier burdens on transport. Also,…

  • rolling motion (mechanics)

    mechanics: Rotation about a moving axis: …combined rotation and translation is rolling motion, as exhibited by a billiard ball rolling on a table, or a ball or cylinder rolling down an inclined plane. Consider the latter example, illustrated in Figure 22. Motion is impelled by the force of gravity, which may be resolved into two components,…

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