Britannica Concise 2005

Tolstoy, Aleksey (Nikolayevich), Count (b. Jan. 10, 1883, Nikolayevsk, Russia—d. Feb. 23, 1945, Moscow) Russian writer. Dis¬ tantly related to the great novelist Leo Tolstoy, he supported the anti- Bolshevik White Army in the Russian Civil War, then emigrated to western Europe, where he wrote one of his finest works, the nostalgic, partly autobiographical Nikita’s Childhood (1921). In 1923 he returned to Russia as a supporter of the Soviet regime. He wrote many works that are purely entertaining and, in wartime, patriotic articles. He won three Sta¬ lin Prizes, for the novel trilogy The Road to Calvary (1920-41), the novel Peter the First (1929-45), and the play Ivan the Terrible (1943).

Tolstoy, Leo Russian Lev Nikolayevich, Count Tolstoy (b. Sept. 9, 1828, Yasnaya Polyana, Tula province, Russian Empire—d. Nov. 20, 1910, Astapovo, Ryazan province) Russian writer, one of the world’s greatest novelists. The scion of prominent aristocrats, Tolstoy spent much of his life at his family estate of Yasnaya Polyana. After a somewhat dis¬ solute youth, he served in the army and traveled in Europe before return¬ ing home and starting a school for peasant children. He was already known as a brilliant writer for the short stories in Sevastopol Sketches (1855-56) and the novel The Cossacks (1863) when War and Peace (1865-69) established him as Russia’s preeminent novelist. Set during the Napoleonic Wars, the novel examines the lives of a large group of char¬ acters, centring on the partly autobiographical figure of the spiritually questing Pierre. Its structure, with its flawless placement of complex char¬ acters in a turbulent historical setting, is regarded as one of the great tech¬ nical achievements in the history of the Western novel. His other great novel, Anna Karenina (1875-77), concerns an aristocratic woman who deserts her husband for a lover and the search for meaning by another autobiographical character. Levin. After its publication Tolstoy underwent a spiritual crisis and turned to a form of Christian anarchism. Advocating simplicity and nonviolence, he devoted himself to social reform. His later works include The Death of Ivan Ilich (1886), often considered the great¬ est novella in Russian literature, and What Is Art? (1898), which con¬ demns fashionable aestheticism and celebrates art’s moral and religious functions. He lived humbly on his great estate, practicing a radical asceti¬ cism and in constant conflict with his wife. In November 1910, unable to bear his situation any longer, he left his estate incognito. During his flight he contracted pneumonia, and he was dead within a few days.

Toltec Nahuatl-speaking people who held sway over what is now cen¬ tral Mexico from the 10th to the 12th century. Whether their urban cen¬ tre was Tula or Teotihuacan is a matter of dispute. In the 10th century they formed a number of small states of various ethnic origins into an empire. They introduced the cult of Quetzalcoatl, and other Toltec religious and military influences spread through the Yucatan region and were absorbed by the Maya. They were noted as builders and craftsmen; artifacts include fine metalwork, gigantic statues, and carved human and animal standard- bearers. They were succeeded by the Aztec. See also Mesoamerican civi¬ lization.

Toluca \to-'lu-ka\ in full Toluca de Lerdo City (pop., 2000: 435,125), capital of Mexico state, central Mexico. At an elevation of about 8,800 ft (2,680 m), it is one of the highest cities in North America. The site of the modern city, founded in 1530, was inhabited by the Otomi Indians by the

13th century. It is a commercial and communications centre in an agri¬ culture and livestock region. Its oldest church was founded soon after the Spanish conquest and rebuilt in 1585. There are many archaeological sites in the area, including some Aztec and Toltec ruins.

toluene Ytal-ya-.wenV Colourless, flammable, toxic liquid hydrocarbon aromatic compound (C 6 H 5 CH 3 ), the methyl derivative of benzene. Found in coal-tar light oil and in petroleum, it is obtained chiefly from the pro¬ cessing of petroleum fractions. It is used as a solvent, diluent, and thin¬ ner; as an antiknock additive in airplane gasoline; and as a raw material for TNT, benzoic acid and its derivatives, saccharin, dyes, photographic chemicals, and pharmaceuticals.

tomato Any fruit of the numerous cultivated varieties of Lycopersicon esculentum, a plant of the nightshade family. The plant is generally much branched and has hairy, strongly odorous, feathery leaves. The droop¬ ing, clustered, yellow flowers are followed by red, scarlet, or yellow fruits, which hang from the many branches of one weak stem. The tomato fruit varies in shape from spherical to elongate and in size from 0.6 in. (1.5 cm) across to more than 3 in. (7.5 cm) across. The Spanish were bringing tomatoes from South America to Europe by the early 16th century; they were introduced to North America from Europe by the 1780s. Tomatoes are used raw, cooked as a vegetable or puree, and pickled, canned, and sun-dried. The term also applies to the fruit of L. pimpinelli folium, the tiny currant tomato.

tomato fruitworm See corn earworm

tomb Home or house for the dead. The term is applied loosely to all kinds of graves, funerary monuments, and memorials. Prehistoric tomb burial mounds, or barrows (artificial hills of earth and stones piled over the remains), were usually built around a hut containing personal effects for use in the afterlife. Burial mounds were a prominent feature of the Tumulus period in Japan (3rd-6th century); these often spectacular monu¬ ments consisted of earthen keyhole-shaped mounds surrounded by moats. Burial mounds, sometimes shaped like animals, were characteristic also of Indian cultures of eastern central North America c. 1000 bc-ad 700. With more advanced technology, brick and stone tombs appeared, often of imposing size. In Egypt tombs assumed great importance, especially in the form of pyramids. In medieval Christian thought, the tomb became a symbol of a heavenly home; this concept appeared in the Roman cata¬ combs, whose walls display scenes of paradise. Since the Renaissance, the idea of the tomb as a home has died out in the West, except as a faint reminiscence in the mausoleums or vaults of modern cemeteries. See also BEEHIVE tomb, CENOTAPH, MASTABA, STELE.

Tomba, Alberto (b. Dec. 19, 1966, San Lazzaro di Savena, Italy) Ital¬ ian Alpine skier. Tomba was born near Bologna and learned to ski there. He won three Olympic gold medals (1988, slalom and giant slalom; 1992, giant slalom), one Alpine World Cup championship (1995), and two World Championship of Skiing gold medals (1996, slalom and giant slalom). He had no success at the 1998 Olympics but won a slalom event at the World Cup in March of that year and then retired from skiing. He achieved a level of fame unusual for an Alpine skier because of his flamboyance on and off the slopes.

Tom big bee \tam-'big-be\ River River, Alabama, U.S. Formed by the confluence of the river’s eastern and western forks near Amory, Miss., it crosses the Alabama border west of Carrollton and flows south nearly 525 mi (845 km) to join the Alabama River and form the Mobile and Tensaw rivers. It is linked to the Tennessee River by the Tennessee-Tombigbee Waterway.

Tombstone City (pop., 2000: 1,504), southeastern Arizona, U.S. The site was named by Ed Schieffelin, who discovered silver there in 1877 after being told that all he would find would be his tombstone. By 1881 a silver rush had drawn prospectors such as Doc Holliday and Johnny

Tomato (Lycopersicon esculentum).

GRANT HEILMAN

© 2006 Encyclopaedia Britannica, Inc.

tomography ► tongues I 1921

Ringo, who brought the town a reputation for lawlessness. Feuds were common, including the 1881 gun battle at the O.K. Corral between the Earp (see Wyatt Earp) and Clanton families. Tombstone was declared a national historic landmark in 1962.

tomography \t6-'ma-gr3-fe\ Radiological technique for obtaining clear X-ray images of internal structures by focusing on a specific plane within the body to produce a cross-sectional image. It allows the exami¬ nation of structures that are obscured by overlying organs and soft tissues and do not show up clearly on conventional X-ray images. See also com¬ puted AXIAL TOMOGRAPHY.

Tompion Ytam-pe-anX, Thomas (baptized July 25, 1639, Northill, Bedfordshire, Eng.—d. Nov. 20,

1713, London) British clockmaker.

Working closely with Robert Hooke and Edward Barlow, he made one of the first English watches with a bal¬ ance spring and patented the cylin¬ der escapement. The most famous clockmaker of his time, he is remem¬ bered as the father of British clock¬ making.

Tompkins, Daniel D. (b. June 21, 1774, Scarsdale, N.Y., U.S.—d.

June 11, 1825, Staten Island, N.Y.)

U.S. politician. He served on the state supreme court (1804-07). As governor (1807-17), he initiated education and penal-code reforms and helped secure state legislation outlawing slavery. An opponent of banking interests, he blocked the chartering of a bank by calling an end to the legislature’s session, the only such occurrence in New York history. He was twice elected vice president with Pres. James Monroe

(1817-25).

tonality Organization of music around a single pitch; more specifically, the Western system of keys that grew out of the modal music of the Renaissance in the 17th century. The term is often used to refer to the network of relationships implicit in the seven principal tones of a given key, each of which has the potential to become the tonic temporarily by means of modulation, whereby a new network of relationships arises. Because of its capacity to extend pitch relationships to remote lengths in an audibly comprehensible way, the tonal system permits the composition of music of great complexity.

Tonatiuh \to-'na-te-ii\ Sun deity of the Aztecs and Nahuas. According to most myths, there were four eras that preceded the era of Tonatiuh, each of which ended by cataclysm. He was viewed as a god constantly threatened by the awesome tasks of his daily birth at sunrise, arduous journey across the sky, and death at each sunset. He was the object of human sacrifice, which was thought necessary to sustain him. Generally represented by a colorful disk, he was depicted in the center of the Aztec calendar, with his eagle’s claw hands clutching human hearts.

tone In linguistics, a variation in the pitch of the voice while speaking. The term is usually applied to languages (called tone languages) in which pitch differentiates words with an identical sequences of consonants and vowels. For example, man in Mandarin Chinese may mean either “deceive” or “slow,” depending on its pitch. In tone languages, what mat¬ ters is not absolute pitch but the pitch of one word relative to another or how pitch changes within a word.

tone See pitch, timbre

Tone, (Theobald) Wolfe (b. Jan. 20, 1763, Dublin, Ire.—d. Nov. 19, 1798, Dublin) Irish republican and rebel. In 1791 he cofounded the Soci¬ ety of United Irishmen to work for parliamentary reform. He organized a Catholic convention of elected delegates that forced Parliament to pass the Catholic Relief Act in 1793. In 1796, seeking to overthrow English rule in Ireland, he convinced France to send an invasion force of 43 ships and 14,000 men, but the ships were dispersed by a storm. Tone again brought an Irish invasion plan to Paris in October 1797, but the principal

French military leader, Napoleon Bonaparte, took little interest. In 1798, with only 3,000 men, he again attempted an invasion; captured and sen¬ tenced to hang, he committed suicide.

tone poem See symphonic poem

Tone \'to-na\ River River, central Honshu, Japan. It rises in the volca¬ nic area of northwestern Kanto region and flows 200 mi (320 km) south¬ east to enter the Pacific Ocean at Choshi. No other river in Japan has been so modified by human activity; its course has been altered and its entire length is confined by dikes. It is an indispensable source for irrigation, industry, and hydroelectricity.

Tonga officially Kingdom of Tonga Island country, South Pacific Ocean. Area: 290 sq mi (750 sq km). Population (2005 est.): 98,600. Capital: Nukualofa. The people are of Polynesian ancestry. Languages: Tongan, English (both official). Religions: Christianity (mostly Protestant; also Roman Catholic, other Christians); also Baha’i. Currency: pa’anga. Tonga comprises an archipelago of some 170 islands that extends north- south in two parallel chains for roughly 500 mi (800 km). The eastern islands are low and formed of coral limestone; those in the west are mountainous and of volcanic origin, and four of the western islands are active volcanoes. The country has a developing free-market economy based mainly on agriculture. Chief products include fish, coconuts, sweet potatoes, and bananas. Tourism also is important. Tonga is a constitutional monarchy with one legislative house; the head of state and government is the king, assisted by the privy council. Tonga was inhabited at least 3,000 years ago by people of the Lapita culture. The Tongans developed a stratified social system headed by a paramount ruler whose dominion by the 13th century extended as far as the Hawaiian Islands. The Dutch vis¬ ited in the 17th century, but effective European contact dates from 1773, when Capt. James Cook arrived and named the archipelago the Friendly Islands. The modern kingdom was established during the reign (1845-93) of King George Tupou I. It became a British protectorate in 1900. This was dissolved in 1970 when Tonga, the only ancient kingdom surviving from the pre-European period in Polynesia, achieved complete indepen¬ dence within the Commonwealth. Tonga was at the centre of a financial scandal in the early 21st century when money in a government trust fund was lost while under the management of an American investor. This added to the country’s ongoing financial problems.

Tonghak See Ch'ondogyo

Tonghak Uprising (1894) Korean peasant rebellion that sparked the Sino-Japanese War. Despite being persecuted for it, impoverished peas¬ ants turned increasingly to Tonghak (“Eastern Learning”; see Ch'ondogyo), a syncretic, nationalistic religion that opposed Western cul¬ ture and espoused equality of all people. When demonstrations staged by Tonghak followers calling for social reform met with a negative govern¬ ment response, the peasantry united with them in a rebellion that suc¬ ceeded in defeating government troops in southern Korea. The government called on China for aid; Japan sent in troops without being asked, and China and Japan clashed. The rebels laid down their arms to defuse tensions; nevertheless, the Sino-Japanese War ensued. The leaders of the uprising, including Ch'oe Si-hyong, were executed.

tongue Muscular organ on the floor of the mouth. It is important in motions of eating, drinking, and swallowing, and its complex movements shape the sounds of speech. Its top surface consists of thousands of raised projections (papillae). The receptors of taste (taste buds) are embedded in the papillae and are sensitive to four basic flavours: sweet, salty, sour, and bitter. More specific flavours are influenced by the sense of smell. The tongue’s appearance (e.g., coated or red) can give clues to disease else¬ where. Disorders of the tongue include cancer (often caused by smoke¬ less tobacco), leukoplakia (white patches), fungal infection, and congenital disorders. Different animals use the tongue to serve varied func¬ tions; for example, frogs have an elongated tongue adapted to capturing prey, the snake’s tongue collects and transfers odours to a specialized sensory structure to help locate prey, and cats use their tongues for groom¬ ing and cleaning.

tongues, speaking in or glossolalia Utterances approximating words and speech that are nonetheless generally unintelligible, usually produced during states of trance or delirium. The religious interpretation of the phenomenon is that the speaker is possessed by a supernatural spirit, is in conversation with divine beings, or is the channel of a divine proc¬ lamation. Speaking in tongues occurred in ancient Greek religion and is

Bracket clock with oak case, ebony veneer, and gilt bronze mounts by Tom¬ pion, c. 1690; in the Victoria and Albert Museum, London

© 2006 Encyclopaedia Britannica, Inc.

1922 I Tonkin ► Topeka

mentioned in the New Testament. According to The Acts of the Apostles, it first occurred among followers of Jesus at Pentecost and reappeared wherever conversion to Christianity occurred. St. Paul claimed to have been adept at it but urged restraint in the practice. Today it is mainly asso¬ ciated with charismatic Protestant movements such as Pentecostausm.

Tonkin Former French protectorate, mainland Southeast Asia, now con¬ stituting the greater part of northern Vietnam. It was part of China from the 2nd century bc until the Vietnamese won independence in the 10th century ad. The French seized the area in 1883, making it a protectorate; it was joined with other regions controlled by France in 1887 to form French Indochina. It was the chief focus in the area of anti-French fight¬ ing after World War II.

Tonkin, Gulf of Arm of the South China Sea, between northern Viet¬ nam and Hainan Island, China. It is 300 mi (500 km) long and 150 mi (250 km) wide. In 1964 the Vietnamese reportedly fired on U.S. ships there, leading the U.S. Congress to adopt the Gulf of Tonkin Resolution that supported increased U.S. involvement in the Vietnam War.

Tonkin Gulf Resolution See Gulf of Tonkin Resolution

Tonle Sap \ton-'la-'sap\ Lake, western Cambodia. The largest freshwa¬ ter body in mainland Southeast Asia, it receives several tributaries as well as the floodwaters of the Mekong River. During the rainy season its area increases from 1,000 sq mi (2,600 sq km) to about 9,500 sq mi (25,000 sq km). At low water it is little more than a reed-infested swamp, with channels for fishing craft. A large carp-breeding and carp-harvesting industry there supports numerous floating fishing villages. The ruins of Angkor lie near its northwestern shore.

Tonnies Vtcen-yosV Ferdinand (Julius) or Ferdinand (Julius) Toennies (b. July 26, 1855, near Oldenswort, Schleswig—d. April 9, 1936, Kiel, Ger.) German sociologist. From 1881 he taught principally at the University of Kiel. In Gemeinschaft und Gesellschaft (1887; “Com¬ munity and Society”), he explored the differences between the organic conception of society, or Gemeinschaft (“community,” a social union based on traditional rules and a shared sense of solidarity), and the social- contract conception of society, or Gesellschaft (“society,” a social union held together by rational self-interest). In practice, he argued, all societ¬ ies show elements of both kinds of organization, because human conduct is neither wholly instinctive nor wholly reasoned.

tonsil Small mass of lymphoid tissue in the wall of the pharynx. The term usually refers to the palatine tonsils on each side of the oropharynx. They are thought to produce antibodies to help prevent respiratory and diges¬ tive tract infection but often become infected themselves (see tonsillitis), mostly in children. There are also pharyngeal tonsils, better known as adenoids, and lingual tonsils, at the base of the tongue. The last have more effective drainage than the others and are rarely infected.

tonsillitis Inflammatory infection of the tonsils, usually with hemolytic streptococci (see streptococcus) or viruses. The symptoms are sore throat, trouble in swallowing, fever, and enlarged lymph nodes on the neck. The infection, which usually lasts about five days, is treated with bed rest and antiseptic gargling. Sulfa drugs or other antibiotics are prescribed in severe bacterial infections to prevent complications. Streptococcal infec¬ tion can spread to nearby structures. Complications may include abscess, nephritis, and rheumatic fever. Tonsils that become chronically inflamed and enlarged require surgical removal (tonsillectomy).

Tony Awards Annual awards for distinguished achievement in the U.S. theatre. Named for the actress-producer Antoinette (Tony) Perry (1888— 1946), the annual awards were established in 1947 by the American The¬ atre Wing and are intended to recognize excellence in plays and musicals staged on Broadway. Awards are given for best play, best musical, best play revival, and best musical revival, and in categories such as acting, directing, music, choreography, set design, and costume design.

tool Device for making material changes on other objects, as by cutting, shearing, striking, rubbing, grinding, squeezing, measuring, or other pro¬ cess. A hand tool is a small manual instrument traditionally operated by the muscular strength of the user; a machine tool is a power-driven mecha¬ nism used to cut, shape, or form materials such as wood and metal. Tools are the main means by which human beings control and manipulate their physical environment.

tool and die making Industrial art of manufacturing stamping dies, plastics molds, and jigs and fixtures to be used in the mass production of

solid objects. The making of dies for punch PRESSes constitutes most of the work done in tool and die shops, and most such pressworking dies are used in the manufacture of sheet-metal parts such as the panels of an automobile body. See also machine tool.

tool steel Specialty steels that are produced in small quantities, contain expensive alloys, and are often sold only by the kilogram and by their individual trade names. They are generally very hard, wear-resistant, tough, nonreactive to local overheating, and frequently engineered to par¬ ticular service requirements. They must be dimensionally stable during hardening and tempering. They contain strong carbide formers such as tungsten, molybdenum, vanadium, and chromium in different combina¬ tions, and often cobalt or nickel to improve high-temperature perfor¬ mance. See also high-speed steel.

Toombs, Robert A(ugustus) (b. July 2, 1810, Wilkes county, Ga., U.S.—d. Dec. 15, 1885, Washington, Ga.) U.S. politician. He was a plan¬ tation owner and a lawyer. He served in the U.S. House of Representa¬ tives (1845-53) and the Senate (1853-61), but he resigned his Senate seat to help form the Confederate States of America. Disappointed at not being chosen its president, he served briefly as secretary of state (1861). He criticized Jefferson Davis’s extralegal policies during the American Civil War and after the war fled to England. He returned to Georgia in 1867 to rebuild his law practice and to help revise the state constitution and restore white supremacy.

Toomer, Jean orig. Nathan Eugene Toomer (b. Dec. 26, 1894, Washington, D.C., U.S.—d. March 30, 1967, Doylestown, Pa.) U.S. poet and novelist of the Harlem Renaissance. He taught briefly before turning to writing. Cane (1923), considered his best work, is an experimental novel that depicts the experience of being black in the U.S.; it had a strong influence on younger black writers. He also wrote for The Dial and other small magazines. He visited the Gurdjieff Institute in France in 1926 and led Gurdjieff groups in Harlem and Chicago. He became a Quaker in 1940. Ambivalent about his mixed racial background and preoccupied with spiritual matters, he avoided race issues in subsequent works.

tooth Any of the hard structures in the mouth used for biting and chew¬ ing and in speech. Each consists of a crown above the gum and one or more roots below it, embedded in the jaw. Its inner pulp contains the blood and nerve supply for the bonelike dentin, covered in the crown by enamel, the hardest tissue in the body. Twenty primary (baby) teeth come in by age 2 1/2 and fall out between ages 5 and 13 to be replaced by 32 per¬ manent teeth. The incisors, in front, are shaped mostly for biting, the pointed canines for tearing, and the premolars and molars for grinding food. The teeth are subject to caries (decay), caused by acid from bacte¬ ria in plaque, a yellowish film that builds up on teeth. Misalignment of teeth between the upper and lower jaws can grind down the teeth and cause problems in chewing. Elsewhere, it is a cosmetic problem. Both can be treated with braces. See also dentistry. See illustration on opposite page.

tooth decay See caries

toothed whale Common term for members of the cetacean suborder Odontoceti. Toothed whales have slicing teeth and a throat large enough to swallow chunks of giant squid, cuttlefish, and fish of all kinds. Included in this group are the beluga, killer whale, pilot whales, sperm whale, and mammalian dolphins, porpoises, and narwhals.

Topa See Northern Wei dynasty

topaz Aluminum silicate mineral, Al 2 Si0 4 (F,OH) 2 , that is valued as a

gemstone. It is formed by fluorine¬ bearing vapours given off during the last stages of the crystallization of igneous rocks. Pure topaz may be colourless and, when brilliant-cut, has been mistaken for diamond. It may also be various shades of yel¬ low, blue, or brown. Imperial topaz, with vivid reddish orange colour, from Minas Gerais, Braz., is very highly valued.

Topeka Uo-'pe-koX City (pop., 2000: 122,377), capital of Kansas, U.S. Situated on the Kansas River,

Topaz from Minas Gerais state, Brazil

LEE BOLTIN

© 2006 Encyclopaedia Britannica, Inc.

Topeka Constitution ► torii I 1923

Cross section of an adult molar. The crown (the part of the tooth above the gum) is protected by a hard outer layer of enamel. The roots sit in a socket in the jawbone and are covered with cementum, a bonelike material. The periodontal ligament anchors the cementum in the jaw and cushions the tooth from the pressures of chewing. The tooth's main portion, the dentin, surrounds the soft pulp, which carries the blood vessels and nerves. Specialized cells of the pulp project threadlike exten¬ sions into the dentin through narrow channels and serve to form new dentin from minerals in the blood.

© MERRIAM-WEBSTER INC.

Topeka was founded in 1854 by a group of antislavery colonists and was prominent in the political conflict between proslavery groups and the antislavery Free Soil Party. In 1859 it was the headquarters for the build¬ ing of the Atchison, Topeka, and Santa Fe Railway system. It has been the state capital since Kansas was admitted to the Union in 1861. The economy is based on agriculture, manufacturing, and governmental ser¬ vices. The Menninger family established its clinics there, making Topeka a national centre for the treatment of mental illness.

Topeka Constitution (1855) Resolution to establish an antislavery territorial government in Kansas. To counter the proslavery government established after passage of the Kansas-Nebraska Act, antislavery settlers met in Topeka to draft a constitution that banned slavery. In January 1856 they elected a free-state governor and legislature, which created two gov¬ ernments. Pres. Franklin Pierce condemned the Topeka document and sup¬ ported the proslavery government. The U.S. House of Representatives voted to admit Kansas under the Topeka Constitution, but the Senate blocked the move. The unresolved situation led to the conflict known as Bleeding Kansas.

topiary Art of training living trees and shrubs into artificial, decorative shapes. Topiary is known to have been practiced in the 1st century ad. The earliest topiary was probably the simple development of edgings, cones, columns, and spires to accent a garden scene. This architectural use gave way to elaborate shapes such as ships, hunters, and hounds. The fashion reached its height in Britain in the late 17th and early 18th cen¬ tury but was displaced by the so-called natural garden.

topology \t3-'pa-lo-je\ In mathematics, the study of the properties of a geometric object that remains unchanged by deformations such as bend¬ ing, stretching, or squeezing but not breaking. A sphere is topologically

equivalent to a cube because, without breaking them, each can be deformed into the other as if they were made of modeling clay. A sphere is not equivalent to a doughnut, because the former would have to be bro¬ ken to put a hole in it. Topological concepts and methods underlie much of modem mathematics, and the topological approach has clarified very basic structural concepts in many of its branches. See also algebraic topol¬ ogy.

Torah \to-'ra, 'to-ro, 'tor-3\ or Pentateuch Vpen-te- 1 tuk\ In Judaism, the divine revelations to Israel; specifically, the first five books of the Bible: Genesis, Exodus, Leviticus, Numbers, and Deuteronomy. By tradition their authorship has been ascribed to Moses, but biblical scholarship has shown that they were written and compiled at a much later date, probably in the 9th-5th century bc, though drawing on much older traditions. The Scroll of the Torah (Sefer Torah) is kept in the Synagogue Ark. The term Torah (but not Pentateuch) is often applied to the whole Hebrew Scripture (i.e., the later books of the Old Testament), or, even more generally, to that and other Jewish sacred literature and oral tradition.

torana Vtor-o-noX Indian gateway, usually of stone, marking the entrance to a Buddhist shrine or stupa or to a Hindu temple. Toranas typi¬ cally consist of two pillars carrying two or three transverse beams that extend beyond the pillars on either side. Strongly reminiscent of wooden construction, toranas are often covered from top to bottom with exquisite sculpture. The four toranas of the Great Stupa at Sanchi (see Sanchi sculp¬ ture) are superb examples. See also torn.

Tordesillas X.tor-da-'sel-yasV, Treaty of (June 7, 1494) Agreement between Spain and Portugal aimed at settling conflicts over lands explored by voyagers of the late 15th century. In 1493 Pope Alexander VI had granted Spain all the lands west of a line 100 leagues (about 320 miles) west of the Cape Verde Islands, in return for an agreement to Christian¬ ize the peoples of the New World;

Portuguese expeditions were to keep to the east. At Tordesillas (a village in Spain), ambassadors from Spain and Portugal moved that line west, thereby allowing Portugal to claim Brazil when it was discovered in

Tori style In Japanese art, a style of sculpture that emerged during the Asuka period (552-645) and lasted into the Nara period (710-784).

Derived from the style of the Chi¬ nese Northern Wei dynasty (ad 386- 534), Tori was named after a sculptor of Chinese descent whose only known piece is a Buddhist triad (623). Works in the Tori style are characterized by slender, elegant bodies, a strong linear interest in drapery, and a tendency toward squatness in the proportion of the faces and also in the relation of the body to the feet.

torii Vt6r-e-,e\ Symbolic gateway marking the entrance to Shinto shrines or other sacred spots in Japan. It has many variations, but it characteristi¬ cally consists of two cylindrical posts topped by a crosswise rectan¬ gular beam extending beyond the posts on either side and a second crosswise beam a short distance below. The top beam often curves upward. Some authorities relate the torii to the Indian torana, others to Manchurian and Chinese gates.

Often painted red, the torii demar¬ cates the boundary between sacred and ordinary space.

© GETTY IMAGES

Bronze triad of Shaka with attendant figures (left figure lost) in the Tori style, Asuka period, 623; in the HoryO-ji, Nara, Japan

COURTESY OF THE HORYU-JI, NARA, JAPAN

© 2006 Encyclopaedia Britannica, Inc.

1924 I Torme ► Torrijos

Torme \'t6r-,ma\, Mel(vin Howard) (b. Sept. 13, 1925, Chicago, Ill., U.S.—d. June 5, 1999, Los Angeles, Calif.) U.S. singer, composer, and actor. Torme began his career playing drums and singing with Chico Marx’s band (1942-43). In 1943 he made his film debut in Higher and Higher :; the same year he formed a quintet, Mel Torme and His Mel-Tones. “Blue Moon,” which he sang in the film Words and Music (1948), became his first solo hit and one of his signature tunes. Torme was one of the great interpreters of ballads in jazz, capable of inspired improvised scat singing. As a songwriter, he is best known for “The Christmas Song.” His smooth vocal timbre is reflected in his sobriquet, “the Velvet Fog.”

tornado Violent, low-pressure storm, relatively small in diameter but with very rapidly rotating winds and an intense updraft near the centre. The relatively low pressure at the centre of a tornado’s funnel-like vor¬ tex causes cooling and condensation, making the storm visible as a revolv¬ ing column of cloud, called the funnel. Tornadoes normally travel at 30—40 mph (50-65 kph). The winds around the vortex average nearly 300 mph (500 kph) and have been known to reach 500 mph (800 kph). Tor¬ nadoes often occur in groups.

Torne River Yt6r-na\ Swedish Tornealv V.tor-ne-'elvV Northernmost river of Sweden. Issuing from Torne Lake near the Norwegian border, it flows southeast and south for 354 mi (570 km) to the Gulf of Bothnia. The lower course, strewn with rapids and mostly non-navigable, forms a sec¬ tion of the Sweden-Finland boundary. It is known for its salmon.

Toronto City (pop., 2001: city, 2,481,494; metro, area, 4,682,897), capi¬ tal of Ontario, Canada. Canada’s most populous metropolitan area, it lies on the northern shore of Lake Ontario. Originally inhabited by Seneca tribes, its site was occupied by a tiny French fort in the mid-18th century. It was founded in 1793 as York by American colonists loyal to the Brit¬ ish. U.S. troops pillaged it during the War of 1812. In 1834 it received its city charter and current name. It became the capital of Ontario in 1867. In 1953-54 it joined neighbouring villages, towns, and townships to form the Municipality of Metropolitan Toronto. In 1967 those 13 municipali¬ ties were reduced to six (Toronto, Etobicoke, North York, Scarborough, York, and the borough of East York), which amalgamated to form the City of Toronto in 1998. It is Canada’s financial and commercial centre, the seat of the Toronto Stock Exchange, and a major international trading centre, with access to Atlantic shipping via the Saint Lawrence Seaway and to major U.S. ports via the Great Lakes. It produces more than half of Canada’s manufactured goods. Extensive immigration (1950s-70s) brought a variety of foreign cultures that transformed it into one of the liveliest cities on the continent. It is the site of the CN Tower (the world’s tallest self-supporting man-made structure), the Hockey Hall of Fame, and the annual Canadian National Exhibition. Its educational institutions include the University of Toronto (1827).

Toronto, University of Public university in Toronto, Ontario, Canada. It was founded in 1843 and reorganized in 1853 and 1887. It comprises nine undergraduate colleges, three formerly independent but now federated universities, four affiliated theological colleges, and numer¬ ous other academic units. It offers undergraduate, graduate, and profes¬ sional degrees in all major disciplines. Notable among its research units are centres for the study of medieval culture and society, religion, Russia and eastern Europe, international relations, drama, comparative literature, biomedical engineering, history of science and technology, and aerospace science.

Toronto Star, The Canadian newspaper, generally ranked as the coun¬ try’s largest. Established in 1892 by 25 printers who had lost their jobs in a labour dispute, it became prosperous after its purchase in 1899 by a group of leading citizens and maintained a liberal editorial outlook, press¬ ing for social change while promoting stronger Canadian nationhood and a greater presence in international affairs. It established its own radio sta¬ tion in 1922. Its outspoken opposition to Nazism made it the first North American newspaper to be banned in Nazi Germany.

torpedo Cigar-shaped, self-propelled underwater missile, launched from a submarine, surface vessel, or airplane and designed to explode on con¬ tact with the hulls of surface vessels and submarines. It contains devices to control depth and direction as well as a detonator for the explosive- filled warhead. Originally the word referred to any explosive charge, including the weapon now known as a submarine mine. The first modern torpedo (1866) carried an 18-lb (8-kg) charge of dynamite in its nose and was powered by a compressed-air engine driving a single propeller; its range was 200-700 yards (180-640 m). Torpedoes were used success¬

fully by submarines in both world wars, when many merchant ships were sunk, mostly by German U-boats. Torpedoes are now usually propelled by battery-powered electric motors.

torque or moment In physics, the tendency of a force to rotate the body to which it is applied. Torque is always specified with regard to the axis of rotation. It is equal to the magnitude of the component of the force lying in the plane perpendicular to the axis of rotation, multiplied by the shortest distance between the axis and the direction of the force compo¬ nent. Torque is the force that affects rotational motion; the greater the torque, the greater the change in this motion.

Torquemada X.tor-ka-'ma-thaV Tomas de (b. 1420, Valladolid, Castile—d. Sept. 16, 1498, Avila,

Castile) First grand inquisitor in Spain (1487-98). A Dominican prior, he became confessor and adviser to Ferdinand V and Isabella I. He guided the Spanish Inquisition, directing its persecution of Jews, Moors, and oth¬ ers identified as heretics, sorcerers, or criminals. Torture was used to obtain evidence, and about 2,000 people were burned at the stake dur¬ ing Torquemada’s tenure. He prob¬ ably influenced Ferdinand and Isabella in their decision to expel the Jews from Spain (1492). His name has become synonymous with the cruel fanaticism of the Inquisition.

Torre, Victor Raul Haya de la

See Victor Raul Haya de a Torre t . ... u ■

lorquemada, lithograph

Torres Bodet Vtor-as-bo-'detV courtesy of the bibliotecanacional, MADRID Jaime (b. April 17, 1902, Mexico

City, Mex.—d. May 13, 1974, Mexico City) Mexican poet, novelist, edu¬ cator, and statesman. He held various diplomatic and government posts, including minister of public education (1943-46) and foreign minister (1946-48). His verse, which early on revealed the influence of Modern- ismo, often returned to the themes of loneliness, a search for identity, and a longing for death. Cripta (1937) is considered to include his most impor¬ tant poems. His poetry was collected in Obra poetica (1967). Of six nov¬ els published between 1927 and 1937, Sombras (1937) is considered his best. Afflicted by cancer, he took his own life.

Torres Strait \'tor-iz\ Passage between the island of New Guinea and Australia’s Cape York Peninsula. It connects the Coral Sea and the Arafura Sea. It was discovered in 1606 by Spanish navigator Luis Vaez de Torres. About 80 mi (130 km) wide, it has many reefs, shoals, and islands, includ¬ ing the Torres Strait Islands, and is treacherous to navigate.

Torres Strait Islands Island group, in the Torres Strait between Aus¬ tralia and New Guinea. The inhabitants are a mixture of Polynesians, Melanesians, and Aboriginals. Administratively part of Queensland, Aus¬ tralia, they consist of three clusters: Western (high, rocky, and barren), Central (coral), and Eastern (volcanic, with dense vegetation); each has its own local government. The islands may be remnants of a land bridge that once linked Asia and Australia. They were annexed by Queensland in the 1870s. Pearls, fishing, and tourism are the main sources of income.

Torricelli Uor-re-'chel-leV Evangelista (b. Oct. 15, 1608, Faenza, Romagna—d. Oct. 25, 1647, Florence) Italian physicist and mathemati¬ cian, inventor of the barometer. He served as secretary to Galileo during the last three months of the latter’s life and was appointed to succeed him at the Florentine Academy. Two years later, pursuing a suggestion by Galileo, he filled a glass tube 4 ft (1.2 m) long with mercury and inverted the tube into a dish. He observed that some of the mercury did not flow out and that the space above the mercury in the tube was a vacuum. After much observation, he concluded that the variation of the height of the mercury from day to day was caused by changes in atmospheric pressure. He never published his findings. His work in geometry aided in the even¬ tual development of integral calculus.

Torrijos \tor-'e-hos\ (Herrera), Omar (b. Feb. 13, 1929, Santiago de Veragua, Pan.—d. Aug. 1, 1981, near Penonome) Virtual dictator of Panama (1968-78). He entered the national guard in 1952 after military studies in Venezuela and the U.S., rose to the rank of general, and came

© 2006 Encyclopaedia Britannica, Inc.

Torshavn > total internal reflection I 1925

to power in 1968 in a coup d’etat. A nationalist and populist, he was one of the few Latin American heads of state to visit Fidel Castro in Cuba, though he suppressed leftist labour agitators and students at home. In 1977 he achieved his supreme goal when U.S. Pres. Jimmy Carter signed two treaties agreeing to transfer the Panama Canal and Canal Zone to Pana¬ manian sovereignty in 1999. He died in a plane crash while on a military inspection tour.

Torshavn \'t6rs-,haun\ Port town (pop., 2000: 16,673), capital of the Faeroe Islands, Denmark. Located on Strpmp Island, it was founded in the 13th century. During World War II the British occupied Torshavn as a defense against German forces in Denmark. It is home to about one-third of the population of the Faeroe Islands. Its main industries are fishing and knitwear.

torsion Vtor-shonV balance Device used to measure the gravitational acceleration at the Earth’s surface. It consists essentially of two small masses at different elevations that are supported at opposite ends of a beam. The latter is suspended from a wire that twists because the masses are affected differently by the force of gravity. When the wire is twisted, an optical system indicates the angle of deflection, and the torque, or twisting force, can be calculated. The torque is correlated with the gravi¬ tational force at the point of observation. Torsion balance may also refer to a device used in weighing, a type of equal-arm balance.

torsion bar Rod or bar that resists twisting (see torque) and has a strong tendency to return to its original position when twisted. In an automobile, a torsion bar is a long spring-steel element with one end held rigidly to the frame and the other end twisted by a lever connected to the axle. It thus provides a spring action for the vehicle.

torsk See cusk

tori' Wrongful act, other than a breach of contract, that injures another and for which the law permits a civil (noncriminal) action to be brought. Relief may be obtained in the form of damages or an injunction. The term derives from Latin tortum, meaning “something twisted, wrung, or crooked.” Assault, defamation, malpractice, negligence, nuisance, product liability, property damage, and trespass are all (apart from their potentially criminal and contractual aspects) torts.

tortoise Any of some 40 species (family Testudinidae) of slow-moving, terrestrial, herbivorous turtles, found in the Old and New Worlds but chiefly in Africa and Madagascar.

Tortoises have a high, domed shell, heavy elephantlike hind legs, and hard-scaled forelegs. The four North American species (genus Gopherus) have a brown shell, about 8-14 in.

(20-35 cm) long, and flattened fore¬ limbs adapted for burrowing. The common, or European, tortoise {Testudo graeca) has a shell about 7-10 in. (18-25 cm) long. Most spe¬ cies of giant tortoises on the Galapa¬ gos and other islands are now rare or extinct. One captive Galapagos tor¬ toise had a shell 4.25 ft (1.3 m) long and weighed 300 lbs (140 kg).

torture Infliction of intolerable physical or psychological pain. Torture has been used by governments throughout history for punishment, coer¬ cion, and intimidation and for extracting confessions and information. A common practice in ancient times, it was defended by Aristotle but elo¬ quently opposed by Cicero, Seneca, and St. Augustine. Beginning in the 12th century, torture was increasingly used in Europe; from the mid-14th through the 18th century it was a common part of the legal proceedings of most European countries. The Roman Catholic church supported its use by the Inquisition in cases of heresy. Common instruments of torture were the strappado (for repeatedly hoisting the body by the wrists behind the back and dropping it), the rack (for stretching the limbs and body), and the thumbscrew (for crushing the thumbs). By 1800 torture was ille¬ gal in many European countries, but it became common again in the 20th century, notably in Nazi Germany and the Soviet Union, and it is still widely practiced in Latin America, Africa, and the Middle East. In 1984 the United Nations adopted an international convention against torture and other forms of cruel, inhuman, and degrading treatment. By the early 21st

century some 130 countries were party to the convention. The belief that only sadists are capable of committing torture was challenged by a study in the 1960s that found that ordinary people could be easily persuaded to inflict pain on others.

Tory Member of a political group in England, especially in the 18th cen¬ tury. Originally an Irish term for an outlaw, the name was applied as a term of abuse to those who supported the hereditary right of James, the Catholic duke of York (later James II), to succeed to the throne of England. They were opposed by the Whigs in that struggle (1679), but the Tories later modified their doctrine of divine-right absolutism. They came to represent the resistance, mainly by the country gentry, to religious tolera¬ tion and foreign entanglements. The Tories’ political power diminished after Viscount Bolingbroke, a leading Tory, fled to France in 1715; Tory sentiment subsequently survived in the unsuccessful Jacobite movement. After 1784, William Pitt the Younger emerged as the leader of a new Tory party, representing the country gentry, merchants, and administrators. After 1815, the party gradually evolved into the Conservative Party, whose members are still referred to as Tories.

Tosa \'to-sa\ Historic region of the Japanese island of Shikoku. It dates at least to the Heian period, when Ki no Tsurayuki (8687-9457), editor of Japan’s first imperially commissioned poetry anthology, wrote a fictional diary drawing on his experiences as governor of Tosa. In 1571 it became a unified domain (han) whose daimyo opposed Tokugawa Ieyasu when he consolidated his control of Japan in the early 17th century; this historical enmity became important at the time of the Meiji Restoration (1868), when samurai from Tosa, like those from Satsuma and ChoshO, helped overthrow the Tokugawa shogunate. See also Itagaki Taisuke; Tokugawa period.

Toscanini V.tas-ko-'ne-neN, Arturo (b. March 25, 1867, Parma, Italy—d. Jan. 16, 1957, New York, N.Y., U.S.) Italian conductor. Tosca¬ nini entered a conservatory at age nine, studying cello, piano, and com¬ position. He began his professional life as a cellist. After substituting for an indisposed conductor in Giuseppe Verdi’s Aida (Buenos Aires, 1886), he conducted in various Italian opera houses, giving the premieres of / Pagliacci (1892) and La Boheme (1896). He was appointed musical direc¬ tor of La Scala, Milan, in 1898, and of the Metropolitan Opera, New York City, in 1908. Principally known for his readings of Verdi’s operas and Beethoven’s symphonies, he also gave remarkable performances of the music of Richard Wagner. Toscanini conducted the New York Philharmonic-Symphony Orchestra from 1928 to 1936. In 1930 he became the first non-German to conduct at Bayreuth, but he stopped per¬ forming in Germany to protest Nazi policies. The NBC Orchestra was formed for him in 1937, and he conducted it until his retirement in 1954.

Tosefta \,to-sef-'ta, to-'sef-toV Supplements to the Mishna compiled c. ad 300. The Tosefta consists of laws attributed to the authorities named in the Mishna and generally follows the topical program and organization of the Mishna. Both works were the effort of Jewish scholars, working mostly in Palestine, who gathered, evaluated, and correlated the most important traditions from a vast and heterogeneous mass of material that had developed since the time of Ezra (c. 450 bc). The Tosefta may have been meant to complement the Mishna by preserving material that appeared marginal or contradictory.

Tostig \'tas-tig\ (d. Sept. 25, 1066, Stamford Bridge, Yorkshire, Eng.) Anglo-Saxon earl of Northumbria. He had strong ties with Norway and became earl of Northumbria in 1055; his severity in subduing the wild northern district stirred revolt in 1065. The rebels won the support of Tostig’s brother Earl Harold (later Harold II) at Oxford, and Tostig went into exile. He gave his services to William I (the Conqueror) and harried the English coast, then joined Norway’s king Harald III Sigurdsson in his invasion of England. Tostig was killed when his brother Harold defeated the invading army at Stamford Bridge.

total internal reflection Complete reflection of a ray of light in a medium such as water or glass, from the surrounding surfaces back into the medium. It occurs when the angle of incidence is greater than a cer¬ tain limiting angle, called the critical angle. In general, it takes place at the boundary between two transparent media when a ray of light in a medium of higher index of refraction approaches another medium of lower index of refraction at more than the critical angle. At all angles less than the critical angle, both reflection and refraction occur. Total internal reflection is responsible for rainbows, atmospheric halos, the sparkle of a diamond, and the path of light through optical fibres.

Galapagos tortoise (Geochelone ele- phantopus).

FRANCISCO ERIZE-BRUCE COLEMAN LTD.

© 2006 Encyclopaedia Britannica, Inc.

1926 I Total Quality Control ► Toulouse-Lautrec

Total Quality Control (TQC) System for optimizing production based on ideas developed by Japanese industries from the 1950s on. The system, which blends Western and Eastern ideas, began with the concept of quality circles, in which groups of 10-20 workers were given respon¬ sibility for the quality of the products they produced. It gradually evolved into various techniques involving both workers and managers to maxi¬ mize productivity and quality, including close monitoring of staff and excellent customer service. The concept of kaizen, the notion that improvement must involve all members of a company, is central to TQC. See also production management.

Total Quality Management (TQM) Management practices designed to improve the performance of organizational processes in busi¬ ness and industry. Based on concepts developed by statistician and man¬ agement theorist W. Edwards Deming, TQM includes techniques for achieving efficiency, solving problems, imposing standardization and sta¬ tistical control, and regulating design, housekeeping, and other aspects of business or production processes. See also International Organization for Standardization (ISO); Total Quality Control (TQC).

total war Military conflict in which the contenders mobilize all of their civilian and military resources in order to obtain a complete victory. It is distinguished from the partial commitment of lives and resources in lim¬ ited war. The modem concept of total war is traced to Carl von Clause- witz, who stressed the importance of crushing the adversary’s forces in battle and described wars as tending constantly to escalate in violence toward a theoretical absolute. The classic 20th-century work is Erich Ludendorff’s The Total War (1935). World Wars I and II are usually regarded as total wars. After World War II, especially during the Cold War, the prospect of an all-out nuclear war made the major powers reluc¬ tant to engage in full-scale international warfare or allow their client states to do so.

totalitarianism Form of government that subordinates all aspects of its citizens’ lives to the authority of the state, with a single charismatic leader as the ultimate authority. The term was coined in the early 1920s by Benito Mussolini, but totalitarianism has existed throughout history throughout the world (e.g., Qin dynasty China). It is distinguished from dictatorship and authoritarianism by its supplanting of all political institu¬ tions and all old legal and social traditions with new ones to meet the state’s needs, which are usually highly focused. Large-scale, organized violence may be legitimized. The police operate without the constraint of laws and regulations. Where pursuit of the state’s goal is the only ideo¬ logical foundation for such a government, achievement of the goal can never be acknowledged. Hannah Arendt’s Origins of Totalitarianism (1951) is the standard work on the subject.

totem pole Carved and painted vertical log, constructed by many Northwest Coast Indian peoples. The poles display mythological images, usually animal spirits, whose significance is their association with the lin¬ eage. Each figure represents a type of family crest. Some poles relate a family legend in the form of pictographs. Poles are erected to identify the owner of a house or other property, welcome visitors, indicate a portal or passageway, mark a gravesite, and even to ridicule an important person who failed in some way. See also symbol; totemism.

totemism Complex of ideas and practices based on the belief in kin¬ ship or mystical relationship between a group (or individual) and a natu¬ ral object, such as an animal or plant. The term derives from the Ojibwa word ototeman, signifying a blood relationship. A society exhibits totemism if it is divided into an apparently fixed number of clans, each of which has a specific relationship to an animate or inanimate species (totem). A totem may be a feared or respected hunted animal or an edible plant. Very commonly connected with origin myths and with instituted morality, the totem is almost always hedged about with taboos of avoid¬ ance or of strictly ritualized contact. Totem, taboo, and exogamy seem to be inextricably intertwined. See also totem pole.

Totonac V.to-to-'nakV North American Indians of east-central Mexico. Some live on cool, rainy high mesas, others in the hot, humid lowlands. Both groups are farmers, but the highlanders sometimes engage in ped¬ dling and wage labour as well and often work on lowland farms in the off-season. Most farm their own land and also perform required labour on land collectively owned by the village. They profess Roman Catholicism but have adapted it to their traditional beliefs.

toucan Vtu-,kan\ Any of about 40 species (family Ramphastidae) of large-billed, long-tailed Central and South American birds. Many species are black with a bold breast colour; their thick, saw-edged bills are brightly and distinctively coloured.

Bands of toucans emit loud barks, bugling calls, and harsh croaks. They eat fruit, insects, lizards, and nestling birds. Toucans deposit two to four eggs in an unlined natural tree cav¬ ity or an abandoned woodpecker hole. Ramphastos species are up to 24 in. (60 cm) long, a third of which may be the bill. Smaller species (tou- canets) are 10-14 in. (25-35 cm) long.

touch-me-not Either of two North American impatiens, also known as jewelweed or snapweed, growing in moist areas. Impatiens capensis, also called I. biflora, typically has crimson-spotted orange flow¬ ers; I. pallida has yellow to white flowers, sometimes spotted with brownish-red. They are common weeds native to extensive regions of eastern North America. Their juice is said to be a remedy for poison-ivy rashes.

touch reception See mechanoreception

touchstone Black, silica-containing stone used in assaying to determine the purity of gold and silver. The metal to be assayed is rubbed on the touchstone, and then a sample of metal of known purity is rubbed on the stone right next to it. The streaks of metal on the stone are treated with nitric acid, which dissolves impurities, thus increasing the contrast between the two samples when compared. Because other metals, such as copper, can be alloyed to silver without changing its colour significantly, the touchstone method is not usually used now to assay silver, though it is still used to assay gold and provides a reasonably accurate guide to quality.

Toulon \tii-'lo n . Siege of (Aug. 28-Dec. 19, 1793) Military engage¬ ment in the French Revolutionary Wars. French royalists handed over the naval base and arsenal at Toulon, France, to an Anglo-Spanish fleet in August. The French Revolutionary army began a siege to recapture the port city and, after months of preparations, successfully assaulted the allied-held forts commanding the anchorage. A battery of French guns, commanded by the young Napoleon Bonaparte, fired on the British fleet and forced it to evacuate the inner harbour, though British and Spanish troops blew up the arsenal and burned 42 French ships before leaving. For his key role in the victory, Napoleon was promoted to brigadier gen¬ eral.

Toulouse \tii-'luz\ ancient Tolosa City (pop., 2004 est.: 426,700), on the Garonne River in southern France. Founded in ancient times, it was taken from its Celtic inhabitants by the Romans in the 1st century bc. After ad 778 it became the seat of the feudal countship of Toulouse. Prot¬ estants were massacred there during the 16th-century Wars of Religion. In 1814 it was the scene of the British victory over the French in the last battle of the Peninsular War. A rail junction and canal port, Toulouse is a centre of the French aviation industry. It has many historic buildings, including a Gothic cathedral and a Romanesque basilica, and the tomb of St. Thomas Aquinas. The university, founded in 1229, is one of the oldest in the world.

Toulouse-Lautrec \tu-Tuz-lo-'trek\ (-Monfa), Henri (-Marie- Raymond) de (b. Nov. 24, 1864, Albi, France—d. Sept. 9, 1901, Mal- rome) French painter and graphic artist. Born to an old aristocratic family, he developed his interest in art during lengthy convalescence after both his legs were fractured in separate accidents (1878, 1879) that left them permanently stunted and made walking difficult. In 1881 he resolved to become an artist; after taking instruction, he established a studio in the Montmartre district of Paris in 1884 and began his lifelong association with the area’s cafes, cabarets, entertainers, and artists. He captured the effect of the movement of dancers, circus performers, and other enter¬ tainers by simplifying outlines and juxtaposing intense colours; the result was an art throbbing with life and energy. His lithographs were among his most powerful works, and his memorable posters helped define the

Gray-breasted mountain toucan (Andi- gena hypoglauca).

PAINTING BY JOHN P. O'NEILL

© 2006 Encyclopaedia Britannica, Inc.

Toungoo dynasty ► Tower I 1927

possibilities of the genre. His pieces are often sharply satirical, but he was also capable of great sympathy, seen most poignantly in his studies of prostitutes (e.g.. At the Salon, 1896). His extraordinary style helped set the course of avant-garde art for decades to come. A heavy drinker, he died at 36.

Toungoo Vtauq-.giA dynasty Ruling house in Myanmar (Burma) from the 15th or 16th century to the 18th century. The founder of the empire is considered to be either King Minkyinyo (r. 1486-1531) or his son Tab- inshwehti (r. 1531-50), who expanded the empire and welded it together. Tabinshwehti’s brother-in-law Bayinnaung (r. 1551-81) extended the dynasty’s reach to include much of Laos and Siam (Thailand). No ruler ever managed to conquer Arakan (in southern Myanmar), though Tabin- shwehti, Bayinnaung, and others tried. The empire slowly disintegrated after Bayinnaung’s death, but the dynasty continued until 1752.

Tour, Georges de La See Georges de La Tour

Tour de France \,tur-d3-'fra n s\ World’s most prestigious and difficult bicycle race. Staged for three weeks each July—usually in some 20 day¬ long stages—the Tour typically comprises 20 professional teams of nine riders each and covers some 3,600 km (2,235 miles) of flat and moun¬ tainous country, mainly in France, with occasional and brief visits to Bel¬ gium, Italy, Germany, and Spain. Each stage of the race is timed, and the rider with the lowest aggregate time for all stages is the winner. Estab¬ lished in 1903 by Henri Desgrange (b. 1865—d. 1940), a French cyclist and journalist, the race has been run every year except during the world wars.

Touraine \tli-'ren\ Historical region, northwestern central France. It encompassed the former province of Touraine; its capital was at Tours. In Roman times it was inhabited by the Gallic Turones. In the 5th century ad it was incorporated in the Visigothic kingdom, and it passed to the Franks in 507. Contested by various powers over the succeeding centu¬ ries, it came under French influence in the early 13th century. It began to decline c. 1700, and the province was abolished in 1789 during the French Revolution. The region, which includes the Loire River valley, known for its magnificent chateaus, is sometimes called the Garden of France.

Toure \tii-'ra\, (Ahmed) Sekou (b. Jan. 9, 1922, Faranah, French Guinea—d. March 26, 1984, Cleveland, Ohio, U.S.) First president of Guinea (1958-84) and a leading African politician. Toure, who claimed to be descended from Samory, helped lead Guinea’s campaign for inde¬ pendence in 1958. He actively supported Kwame Nkrumah’s program for African unity and gave Nkrumah asylum when he was deposed in 1966. A member of the (Organization of African Unity (now African Union), he was viewed internationally as a moderate Islamic leader. After an unsuc¬ cessful invasion from neighbouring Portuguese Guinea (now Guinea- Bissau) in 1971, he imposed harsh domestic measures and ruled with an iron hand.

Tourette \tu-'ret\ syndrome Rare neurological disease that causes repetitive motor and vocal tics. Named for Georges Gilles de la Tourette, who first described it in 1885, it occurs worldwide, is usually inherited, generally begins at ages 2-15, and is three times more common in males. Motor tics occur first in about 80% of cases, compulsions to utter abnor¬ mal sounds in the rest. A compulsion to utter obscenities, once thought characteristic, is often absent. Repetition of words heard and spontaneous repetition of one’s own words are two distinctive symptoms. Other vocal tics may include meaningless sounds. Motor tics may be virtually unno- ticeable; more complex ones may appear intentional (e.g., hopping, clap¬ ping). Sleep, intense concentration, and exertion tend to suppress the tics; emotional stress worsens them. Unlike psychiatric compulsive disorders, Tourette syndrome has a neurological origin and may improve with psy¬ chogenic drugs. Brain neurotransmitter abnormalities may be involved, but the underlying cause remains uncertain.

tourmaline Vtor-mo-lon, 'tor-mo-.lenV Complex silicate mineral that is often used as a gemstone. Three types of tourmaline, distinguished by the presence of certain elements, are usually recognized: iron tourmaline (schorl) is black, magnesium tourmaline (dravite) is brown, and alkali tourmalines may be pink, green, blue, or colourless. Tourmaline is most common in granite pegmatites. Gem-quality stones are found especially in the U.S., Brazil, Russia, and Madagascar.

Tourneur Vtor-norV Cyril (b. c. 1575—d. Feb. 28, 1626, Kinsale, County Cork, Ire.) English dramatist. His early years were devoted to lit¬ erature; after c. 1613 he served in the government. His reputation rests

largely on The Atheist’s Tragedie (1611), a verse drama rich in macabre imagery. He may be the author of The Revenger’s Tragedie (1607), but most recent scholarship attributes it to Thomas Middleton; though earlier than The Atheist’s Tragedie, it is more mature in its structure and sombre brilliance. Tourneur also wrote the poetical satire The Transformed Meta¬ morphosis (1600).

Tours \'tlir\ City (pop., 1999: 132,820), northwest-central France. Gal¬ lic tribes inhabited the site before the Roman conquest. In the 3rd cen¬ tury ad it was made an episcopal see, but the Christian community remained small until St. Martin became bishop in the 4th century; a mag¬ nificent basilica was raised above his tomb in the late 5th century, attract¬ ing pilgrims for hundreds of years. In the 5th century Tours became part of the Frankish dominion; Charles Martel defeated Moorish invaders nearby at the Battle of Tours/Poitiers in 732. Under Alcuin it developed as a centre of learning. Though it prospered in the Middle Ages, it declined with the 17th-century emigration of the Protestant Huguenots. It was the seat of French government during the siege of Paris (1870) in the Franco- Prussian War. The chief tourist hub for the Loire valley, Tours still has the remains of the basilica of St. Martin. Tours is the birthplace of Honore de Balzac.

Tours/Poitiers \pwa-'tya\, Battle of (October 732) Victory won by the Frankish mayor of the palace Charles Martel over Muslim invaders from Spain. Charles led Frankish troops against a Muslim army seeking to gain control of Aquitaine. The Arab leader, 'Abd-al-Rahman al-Ghafiqi, was killed, and the Arabs retreated. The battle itself was part of Charles’s campaign against the Muslims in the south and was not decisive. It did, however, mark the end of the Muslim invasions of Frankish territory and contributed to Frankish consolidation of the region. The Frankish victory greatly enhanced Charles’s prestige and that of his family, the Carolin- GIANS.

Toussaint-Louverture Vtii- 1 sa n -Tu-v3r- 1 tur\ orig. Francois Domi¬ nique Toussaint (b. c. 1743, Breda, near Cape Francis, Saint- Domingue—d. April 7, 1803, Fort-de-Joux, Fr.) Leader of the Haitian independence movement during the French Revolution. Born a slave, he was freed in 1777. In 1791 he joined a slave rebellion and soon assembled an army of his own, which he trained in guerrilla warfare. When France and Spain went to war in 1793, he and other black commanders joined the Spaniards, but in 1794 he switched his allegiance to the French because France, unlike Spain, had recently abolished slavery. His revolt created the first independent nation in Latin America. He rose from lieu¬ tenant governor to governor-general of Saint-Domingue and gradually rid himself of nominal French superiors. Treaties with the British secured their withdrawal, and he began trade with them and the U.S. In 1801 he turned his attention to Santo Domingo, the Spanish-controlled portion of Hispaniola, driving out the Spanish and freeing the slaves there. He made himself governor-general for life. He was deposed by the French in 1802 and died in custody in France. See also Jean-Jacques Dessalines.

Toutates See Teutates

Towada \to-'wa-da\, Lake Lake, northern Honshu, Japan. It occupies a volcanic crater and is 27 mi (44 km) in circumference. The third deep¬ est lake in Japan, it is 1,096 ft (334 m) deep at its centre. It lies in Towada-Hachimantai National Park, a popular recreation area.

tower Any freestanding or attached structure that is relatively tall in proportion to its base. The Romans, Byzantines, and medieval Europeans built defensive towers as part of the fortifications of their city walls (e.g., the Tower of London). Indian temple architecture uses towers of various types (e.g., the sikhara ). Towers were an important feature of churches and cathedrals built in the Romanesque and Gothic periods. Some Gothic church towers were designed to carry a spire; others had flat roofs. The Italian campanile could either be attached to a church or freestanding. The use of towers declined somewhat during the Renaissance but reappeared in Baroque architecture. The use of steel frames enabled buildings to reach unprecedented heights; the Eiffel Tower in Paris was the first structure to reveal the true vertical potential of steel construction.

Tower, Joan (b. Sept. 6, 1938, New Rochelle, N.Y., U.S.) U.S. com¬ poser. She studied piano as a child, attended Bennington College, and completed her music studies at Columbia University. In 1969 she formed the Da Capo Chamber Players, for which she played piano and wrote many pieces; she left the group in 1984. She is chiefly known for her colourful and often whimsical orchestral compositions, including Sequoia

© 2006 Encyclopaedia Britannica, Inc.

1928 I Tower of London ► Toynbee

(1981), Fanfare for the Uncommon Woman (1987), and Silver Ladder (1987). Since 1972 she has taught at Bard College.

Tower of London Royal fortress on the northern bank of the River Thames. The central keep, or donjon, known as the White Tower because of its limestone, was begun c. 1078 by William I the Conqueror inside the Roman city wall. In the 12th—13th century the fortifications were extended beyond the wall, the White Tower becoming the nucleus of a series of concentric defenses. The only entrance from the land is at the southwest¬ ern corner; when the river was still a major highway, the 13th-century water gate was much used. Its nickname, Traitors’ Gate, derives from the prisoners brought through it to the Tower, long used as a state prison; many were murdered or executed there.

towhee Vto-.he, 'to-,e,\ Any of several North American songbirds (pas¬ serine family Fringillidae, sometimes Emberizidae), long-tailed thicket- dwellers that noisily scratch the ground for food. The name is from the call of the rufous-sided towhee {Pipilo erythrophthalmus), known as chewink in the southeastern U.S.; it ranges from Canada to Central America. About 8 in. (20 cm) long, it has a dark hood, white-cornered tail, and rusty flanks; western sub¬ species have white-spotted wings.

The brown towhee (P. fuscus) of the western U.S. is a plain-looking bird.

The green-tailed towhee ( Chlorura chlorura ), also western, is gray, white, and greenish, with a red-brown cap.

town meeting Legislative assembly of a U.S. town in which all or some voters are empowered to conduct the community’s affairs. Town meetings first took place in New England in the colonial era and are still largely a New England phenomenon, partly because the region’s towns tend to hold powers that are granted to counties elsewhere. The meetings are normally held annually. Executive authority is usually held by a three- or five-member board. Open town meetings, which are widely regarded as an exceptionally pure form of democracy, allow all registered voters to vote on articles listed on the agenda, or warrant; representative town meetings allow only elected members to vote.

Townes, Charles H(ard) (b. July 28, 1915, Greenville, S.C., U.S.) U.S. physicist. He studied at Furman University, Duke University, and the California Institute of Technology and worked for Bell Labs before joining the faculty of Columbia University (1948). In the early 1950s he and his students constructed the first maser and showed that a similar device producing visible light was also possible. For his role in the inven¬ tion of the maser and later the laser, he shared a 1964 Nobel Prize with Aleksandr M. Prokhorov (b. 1916) and Nikolay G. Basov (b. 1922).

Townsend family U.S. cabinetmakers in Newport, R.I., of the 17th— 18th century. The brothers Job (1699-1765) and Christopher (1701-1773) were the first generation involved in furniture making. Job’s daughter married his apprentice John Goddard (see Goddard family). Five of Job’s sons and two of Christopher’s sons became cabinetmakers. The Goddard- Townsend group was best known for case furniture characterized by block fronts (divided into three panels, with the central panel recessed) and decorative carved shell motifs, frequently in the graceful and somewhat ornate style developed by Thomas Chippendale.

Townshend Vtaun-zond\ (of Rainham), Charles Townshend, 2nd Viscount (b. April 18, 1675, Raynham Hall, Norfolk, Eng.—d. June 21, 1738, Raynham) British politician. He succeeded to his father’s title in 1687, married the sister of Robert Walpole, and served as secre¬ tary of state (1714-16). With Walpole, Townshend led the Whig Party and became president of the privy council (1720). Again secretary of state (1721-30), he formed the League of Hanover (1725), which allied Brit¬ ain, France, and Prussia against Austria and Spain. He resigned when Walpole, by then the dominant minister, opposed an aggressive policy against Austria. Also interested in agricultural reform, Townshend devel¬ oped the use of turnips in crop rotation, earning the nickname Turnip Townshend.

Townshend Acts (1767) British parliamentary measures to tax the American colonists. The series of four acts imposed duties on imports of lead, paint, glass, paper, and tea and established a board of customs com¬ missioners to enforce collection. Colonial quartering of British troops was also revived. The colonists protested the new measures as taxation with¬ out representation and resisted compliance. Nonimportation agreements among colonial merchants cut British imports in half by 1769. In 1770 all the duties except the tax on tea were repealed.

toxic shock syndrome Bacterial disease caused by a toxin produced by the bacterium Staphylococcus aureus. It was first recognized in 1978 in women using superabsorbent tampons. High fever, diarrhea, vomiting, and rash may progress to abdominal tenderness, drop in blood pressure, shock, respiratory distress, and kidney failure. The syndrome also has other causes, including postsurgical infection. Antibiotics are not effective. With intensive supportive therapy, most patients recover in 7-10 days, but 10-15% die. Many patients have a milder recurrence within eight months.

toxicology Study of poisons and their effects, particularly on living systems. It overlaps with biochemistry, histology, pharmacology, pathology, and other fields. Its functions have expanded from identifying poisons and searching for treatments to include forensic toxicology (see forensic medi¬ cine) and testing and detection of a fast-growing number of new poten¬ tially toxic substances used in workplaces, in agriculture (e.g., insecticides, other pesticides, fertilizers), in cosmetics, as food additives, and as drugs (see drug poisoning). Perhaps the area of largest expansion is the study of toxic waste in the air, water, and soil, including chlorofluorocarbons, acid rain, dioxin, and radioactive isotopes.

toxin Any substance poisonous to an organism; often restricted to poi¬ sons produced by living organisms. In addition to those from such micro¬ organisms as bacteria (see bacterial diseases), dinoflagellates, and algae, there are toxins in fungi (mycotoxins; see aflatoxin; mushroom poisoning), higher plants (phytotoxins), and animals (zootoxins, or venoms). The plants include nightshade (see nightshade family), poison hemlock, foxglove, mistletoe, and poison ivy. Many plant toxins (e.g., pyrethrins, nicotine, rotenone) apparently protect their producers against certain animals (espe¬ cially insects) or fungi. Similar defensive secretions in animals may be widely distributed or concentrated in certain tissues, often with some sort of delivery system (e.g., spines, fangs). Animals such as spiders and snakes use venoms to catch prey and often for defense. Many normally edible fishes and shellfishes become poisonous after feeding on toxic plants or algae. See also antidote; food poisoning.

toxoid \'tak-,s6id\ Bacterial toxin that has been made inactive but can still combine with or stimulate formation of antibodies. In many bacterial diseases, the bacteria produce a toxin that causes the disease manifesta¬ tions. Heating the toxin or treating it chemically converts it into a harm¬ less toxoid that can be injected into a human or a nonhuman animal to confer immunity from subsequent infection. The vaccines for tetanus and diphtheria are toxoids.

toy Plaything for a child or infant. Toys survive from the remote past and from a great variety of cultures. They range from the simple to the com¬ plex, from a stick or piece of string that becomes a toy in a child’s hands to complex mechanical and electronic devices. Perennial favorites include balls, jump ropes, dolls, drums, whistles, dice, jackstones, board games, marbles, play weapons, and costumes. In the modern era the toy industry has grown tremendously, especially with the advent of computer games.

toy dog Any of several breeds of dogs that were bred to be small, por¬ table, good-natured companions. Toy dogs were traditionally pampered and treasured by aristocracy around the world, and several breeds are ancient. They range from hairless (e.g., the Chinese crested dog) to pro¬ fusely coated (e.g., the Shih tzu). Some breeds, such as the Pekingese, could be owned only by royalty. The Cavalier King Charles spaniel was a favour¬ ite of English royalty. English toy spaniels and toy poodles are popular in the U.S. The miniature pinscher resembles the Doberman pinscher but has a different ancestry. Other toy dogs include the affenpinscher, Maltese, pap- illon, Pomeranian, and Yorkshire terrier.

Toynbee, Arnold (Joseph) (b. April 14, 1889, London, Eng.—d. Oct. 22, 1975, York, North Yorkshire) English historian. Long a professor at the University of London and the Royal Institute of International Affairs, Toynbee also held positions with the British Foreign Office. He is best known for his 12-volume A Study of History (1934-61), which put forward a philosophy of history, based on an analysis of the development and

Rufous-sided towhee (Pipilo eryth¬ rophthalmus)

JOHN H. GERARD FROM THE NATIONAL AUDUBON SOCIETY COLLECTION/PHOTO RESEARCHERS

© 2006 Encyclopaedia Britannica, Inc.

Toyota Motor Corp. ► Trade I 1929

decline of 26 civilizations. Criticisms of his Study include his use of myths and metaphors as being of comparable value to factual data and his reliance on a view of religion as a regenerative force. His other works include Civi¬ lization on Trial (1948), East to West (1958), and Hellenism (1959).

Toyota Motor Corp. Largest Japanese automobile manufacturer and one of the largest automotive companies in the world. It was established in 1933 as a division of the Toyoda Automatic Loom Works, Ltd., and in 1937 it was incorporated as the Toyota Motor Co., Ltd. Toyota later estab¬ lished many related companies, including Toyoda Machine Works, Ltd. (1941), and Toyota Auto Body, Ltd. (1945). In the 1960s and ’70s the company expanded rapidly, exporting large numbers of cars to foreign markets. Following consolidations among many of its business units, the company took the name Toyota Motor Corp. in 1982. It has assembly plants and distributors in many foreign countries, and it owns subsidiar¬ ies that produce cars and car parts, trucks, steel, synthetic resins, and industrial equipment. Its brands include Toyota and Lexus.

Toyotomi Hideyoshi \,he-de-'yo-she\ (b. 1536/37, Nakamura, Owari province, Japan—d. Sept. 18, 1598, Fushimi) One of the three unifiers of premodern Japan (with Oda Nobunaga and Tokugawa Ieyasu) who brought the nation out of its Warring States period. He began life as a peasant but was raised to the rank of samurai (warrior) while a soldier for Nobunaga. After Nobunaga’s death, he was appointed kampaku (chancellor to the emperor). Having concluded an alliance with his former rival Ieyasu, he became in 1590 the head of an alliance of daimyo that constituted a gov¬ ernment of national unification. To stabilize society, he imposed the divi¬ sion of society into warriors, farmers, artisans, and tradesmen (an adaptation of ancient Chinese social divisions) and confiscated swords from all but the warriors. With visions of empire, he made two destruc¬ tive but unsuccessful attempts to invade Korea (1592, 1597). After his death, power passed to Ieyasu.

TQC See Total Quality Control TQM See Total Quality Management

tracery In architecture, bars or ribs used decoratively in windows, espe¬ cially the ornamental openwork in Gothic windows. In the earliest phase, two or three narrow, arched windows were placed close together under a single large arch, with the section of wall between the small and large arches pierced by a circular or four-lobed opening. The complexity of this plate tracery increased, reaching a climax in the magnificent windows of Chartres Cathedral. After c. 1220 windows began to be subdivided by mullions, or upright bars, that continued at the head of the window to branch and form the patterns of bar tracery. Elaborate bar tracery soon became one of the most important elements of Gothic architecture and one of its finest achievements, as in the rose windows of the French Rayon- nant style. The bar tracery of the parallel English Decorated style formed netlike patterns based on the circle, arch, trefoil, and quatrefoil. By the late 14th century, the Perpendicular style replaced curvilinear tracery with straight mullions extending to the top of the main arch, connected at intervals by horizontal bars.

trachea \'tra-ke-9\ or windpipe Tube in the throat and upper thoracic cavity through which air passes in respiration. It begins at the larynx and splits just above heart level into the two main bronchi, which enter the lungs. In adults it is about 6 in. (15 cm) long and 1 in. (2.5 cm) in diam¬ eter. Its structure—a membrane strengthened by 16-20 cartilage rings open in the back, with their free ends connected by muscle bands—allows the trachea to stretch and contract in breathing. An inner mucous mem¬ brane has cilia (see cilium) that project inward to trap particles. Muscle fibres over and alongside the trachea contract in response to cold air or irritants in inhaled air; in coughing, the airway narrows to about one-sixth of its normal size to increase the speed and force of exhalation and to dislodge foreign bodies. Such diseases as diphtheria, syphilis, tuberculosis, and typhoid often involve the trachea.

tracheitis \,tra-ke-'I-t3s\ Inflammation and infection of the trachea. Inhaled irritants can injure the tracheal lining and increase the chance of infection (bacterial or viral). Acute infections, usually bacterial, produce fever, fatigue, and swelling of the tracheal lining but generally do no great damage. Chronic infections, promoted by irritants such as heavy smoking and alcohol abuse, cause progressive tissue degeneration and scarring.

tracheophyte See vascular plant

trachyandesite See latite

trachyte \'tra-,klt, 'tra-,k!t\ Light-coloured, very fine-grained igneous rock composed chiefly of alkali feldspar with only minor mafic minerals (biotite, hornblende, or pyroxene). Trachyte is commonly found in volcanic regions; like many volcanic rocks, it shows a streaked or banded struc¬ ture due to flowing of the congealing lava.

track and field or athletics Variety of sport competitions held on a running track and on the adjacent field. It is the oldest form of organized sports, having been a part of the ancient Olympic Games from c. 776 bc to ad 393. Modem events include various sprint and middle- and long¬ distance races, relay races, hurdling, steeplechase, high jump, pole vault, long

JUMP, TRIPLE jump, SHOT put, DISCUS throw, HAMMER THROW, JAVELIN throw, DECATH¬ LON, PENTATHLON, and HEPTATHLON. CROSS-COUNTRY RUNNING, MARATHONS, and speed walking, which are rarely held on a track, are usually considered adjuncts of track-and-field athletics. Events are held indoors and outdoors, and records are kept separately; some events are modified or eliminated for indoor competition.

Tractarian movement See Oxford movement

tractor High-power, low-speed traction vehicle. The two main types are wheeled and continuous-track. Most modem tractors are powered by internal-combustion engines running on gasoline or diesel fuel. Tractors are used in agriculture, construction, and road building, for pulling equip¬ ment such as plows and cultivators, for pushing implements such as bull¬ dozers and diggers, and for operating stationary devices such as saws and winches. The first tractors grew out of the steam engines used on farms in the late 19th century; in 1892 an Iowa blacksmith, John Froehlich, built the first farm vehicle powered by a gasoline engine. The tractor revolu¬ tionized farming, displacing draft animals and many farm workers. By World War I the tractor inspired the tanks built by the British and French.

Tracy, Benjamin F(ranklin) (b. April 26, 1830, near Owego, N.Y., U.S.—d. Aug. 6, 1915, New York, N.Y.) U.S. public official. He served as a county district attorney (1853-59) and, after fighting in the Ameri¬ can Civil War, as U.S. attorney (1866-73). Appointed secretary of the navy (1889-93) by Pres. Benjamin Harrison, he continued the expansion of the navy begun by William C. Whitney, authorizing construction of new battleships and cruisers. His departmental reforms and modernization con¬ tributed to eventual U.S. naval superiority.

Tracy, Spencer (Bonaventure) (b. April 5, 1900, Milwaukee, Wis., U.S.—d. June 10, 1967, Beverly Hills, Calif.) U.S. film actor. He enrolled in the American Academy of Dramatic Arts in New York City in 1922 and was soon earning roles on Broadway. He first starred on Broadway in The Last Mile (1930) and on film in Up the River (1930). Noted for his craggy features and his sincere performances, he became one of the top stars of the 1930s and ’40s, winning Academy Awards in Captains Courageous (1937) and Boys Town (1938)—the first actor to win con¬ secutive Oscars for best actor—and being nominated for seven other roles, including Inherit the Wind (1960) and Judgment at Nuremberg (1961). He had a long relationship with Katharine Hepburn, with whom he cos¬ tarred in nine films, including Woman of the Year (1942), Adam’s Rib (1949), and Guess Who’s Coming to Dinner (1967).

trade, balance of See balance of trade

Trade, Board of Organized market for the exchange of commodity contracts (see commodity exchange). The Toronto Board of Trade, one of the earliest, was incorporated in 1845. The first grain-futures exchange in the U.S. was organized in Chicago in 1848. The Chicago Board of Trade (CBOT) began as a voluntary association of prominent Chicago grain merchants and was chartered by the Illinois legislature in 1859. Initially it sold grain by sample; later it introduced a system of inspection and grading to standardize the market and facilitate trading. By 1858 access to the trading floor was limited to members with seats on the exchange. It became the world’s largest commodity exchange in terms of volume and value of business.

Trade, Board of in full Lords Commissioners of Trade and Plantations Advisory body that supervised American colonial affairs. Established in 1696 to replace the Lords of Trade (1675-96), it examined colonial legislation to ensure maximum benefit to British trade policies. The board nominated colonial governors, recommended laws affecting the colonies to Parliament, and heard complaints from the colonies about its administrators. It lacked executive or legislative powers, but it became the primary colonial policy-making body of the British government. It was abolished in 1782.

© 2006 Encyclopaedia Britannica, Inc.

1930 I trade ► Trajan

trade, restraint of See restraint of trade

trade, terms of Relationship between the prices at which a country sells its exports and the prices paid for its imports. If a country’s export prices rise relative to import prices, its terms of trade are said to have moved in a favourable direction, since, in effect, it now receives more imports for each unit of goods exported. The terms of trade, which depend on the world supply of and demand for the goods involved, indicate how the gains from international trade will be distributed among trading coun¬ tries. An abrupt change in a country’s terms of trade (e.g., a drastic fall in the price of its main export) can cause serious problems in its balance OF PAYMENTS. See also COMPARATIVE ADVANTAGE.

trade agreement Any contractual arrangement between states con¬ cerning their trade relations. Trade agreements may be bilateral or mul¬ tilateral, that is, between two states or more than two. For most countries international trade is regulated by unilateral barriers, including tariffs, nontariff barriers, and government prohibitions. Trade agreements aim to reduce such barriers and thus provide all parties with the benefits of increased trade. Reciprocity is a necessary feature of trade agreements, since neither state will be willing to sign the agreement unless it expects to gain as much as it loses. Another common feature is a most-favoured¬ nation clause, which provides against the possibility that one of the par¬ ties to the current agreement will later offer lower tariffs to another country. Agreements often include clauses providing for “national treat¬ ment of nontariff restrictions,” meaning that both states promise not to duplicate the properties of tariffs with nontariff restrictions such as dis¬ criminatory regulations, selective excise taxes, quotas, and special licens¬ ing requirements. General multilateral agreements are sometimes easier to reach than separate bilateral agreements, since the gains to efficient producers from worldwide tariff reductions are large enough to warrant substantial concessions. The most important modem multilateral trade agreement was the General Agreement on Tariffs and Trade (GATT), which reduced world tariff levels and greatly expanded world trade. Such agree¬ ments continue under the aegis of the World Trade Organization (WTO), which replaced GATT in 1995. See also NAFTA.

trade show or trade fair Temporary market organized to promote trade, where buyers and sellers gather to transact business. Trade fairs are organized at regular intervals, generally at the same location and time of year. They are especially common in Europe and Asia, where nearly every country has at least one major annual international exposition. They range in scope from those dealing with one industry or branch of industrial pro¬ duction to general exhibits of goods and merchandise. Trade shows and conventions confined to a single industry or even to a specialized seg¬ ment of an industry have become increasingly common.

trademark Mark used by a manufacturer or merchant to identify the origin or ownership of goods and to distinguish them from others. Trade¬ marks may be words or groups of words, letters, numerals, devices, names, the shape or other presentation of products or their packages, or combinations of colours. A trademark (indicated by ™ or, when regis¬ tered, by the symbol ®) is considered the property of the holder and is protected by law from unauthorized use by others. In most countries, reg¬ istration is a prerequisite for ownership and protection of the mark. In the U.S., however, the trademark right is granted by the mere use of the mark, though registration often proves legally advantageous. See also copyright.

Trades Union Congress (TUC) National organization of British labour unions. It was founded in 1868 to hold annual conferences of inde¬ pendent unions. It included only skilled workers until 1889, when unions of unskilled workers were admitted. In 1900 the TUC helped found a separate labour organization, the Labour Representation Committee, renamed the Labour Party in 1906. After World War I the TUC was gov¬ erned by a General Council, which had powers to deal with interunion conflicts and intervene in disputes with employers. In the 1930s and ’40s, it was the spokesman for industrial labour in dealings with the govern¬ ment. The organization continued to help formulate economic policy until 1979, when a Conservative government came to power, leading to a decline in TUC membership in the 1980s. In the late 1990s, under Labour prime minister Tony Bair, the TUC was encouraged to back “workplace partnerships” between unions and employers.

Trafalgar \tro-'fal-g3r\, Battle of (Oct. 21, 1805) Naval engagement in the Napoleonic Wars that established British naval supremacy in Europe. It was fought west of Cape Trafalgar, Spain, between a Franco- Spanish fleet of 33 ships under Pierre de Villeneuve (1763-1806) and a

British fleet of 27 ships under Horatio Nelson. As Villeneuve tried to slip out of the besieged port of Cadiz, he was caught by Nelson. The French ships formed a single line and were attacked by the English at two points. After sending the famous signal “England expects that every man will do his duty,” Nelson broke through the centre of the French line and in the pell-mell battle captured Villeneuve and 20 ships. Near the end of the battle. Nelson was mortally wounded by a sniper. No British ships were lost, and Napoleon abandoned his plan to invade England.

tragedy Drama of a serious and dignified character that typically describes the development of a conflict between the protagonist and a superior force (such as destiny, circumstance, or society) and reaches a sorrowful or disastrous conclusion. Tragedy of a high order has been cre¬ ated in three periods and locales, each with a characteristic emphasis and style: Attica, in Greece, in the 5th century bc; Elizabethan and Jacobean England (1558-1625); and 17th-century France. The idea of tragedy also found embodiment in other literary forms, especially the novel. See also COMEDY.

tragicomedy Literary genre consisting of dramas that combine ele¬ ments of tragedy and comedy. Pautus coined the Latin word tragicoco- moedia to denote a play in which gods and mortals, masters and slaves reverse the roles traditionally assigned to them. In the Renaissance and after, tragicomedy was mainly comic, though Elizabethan and Jacobean tragedies almost always include some comic or grotesque elements. Mod¬ em tragicomedy is sometimes used synonymously with absurdist drama, which suggests that laughter is the only response left to people faced with an empty and meaningless existence.

Traherne Vtro-'harnV Thomas (b. 1637, Hereford, Eng.—d. 1674, Teddington) English mystical poet and religious writer. He was ordained in the Anglican church in 1660. Most of his works were unknown for centuries. The discovery in 1896 in a London street bookstall of the manu¬ scripts of Poetical Works (1903) and the prose Centuries of Meditations (1908) created a literary sensation. Later the manuscript of Poems of Felicity (1910) was discovered in the British Museum. His poetry, though sometimes original and intense, is overshadowed by his vivid prose.

Trail of Tears Forced migration of the Cherokee Indians in 1838-39. In 1835, when gold was discovered on Cherokee land in Georgia, a small minority of Cherokee ceded all tribal land east of the Mississippi for $5 million. The U.S. Supreme Court invalidated the deal, but the ruling was ignored by state officials and Pres. Andrew Jackson refused to enforce it. The subsequent eviction and 116-day forced march of thousands of Chero¬ kee to Oklahoma was badly mismanaged, and inadequate food supply, frigid weather, and the cruelty of escorting troops led to the death of about 4,000 Cherokee.

trailing arbutus \ar-'byu-t3s\ or mayflower Trailing evergreen plant ( Epigaea repens) of the heath family, native to sandy or boggy, acidic woodlands of eastern North America. Its leaves are oblong and hairy, and its white, pink, or rosy flowers grow in dense clusters. It is grown in shady wildflower gardens and as ground cover in terraria.

training, transfer of In psychology, the effect of having learned one activity on an individual’s execution of other activities. Positive transfer occurs when a previously acquired skill enhances one’s performance of a new one. Negative transfer occurs when the previously acquired skill impairs one’s attempt to master the new one.

Trajan Vtra-j9n\ in full Caesar Divi Nervae Filius Nerva Tra- ianus Optimus Augustus or Caesar Nerva Traianus Ger- manicus orig. Marcus Ulpius Traianus (b. Sept. 15?, ad 53, Ital- ica, Baetica—d. Aug. 8/9, 117, Seli- nus, Cilicia) Roman emperor (98- 117), the first born outside Italy. He had military commands in Asia and Europe before being named consul in 91. In 97 he was adopted by Nerva as his successor. After Nerva’s death in 98, he deified the former emperor and named himself Jupiter’s repre-

Trajan, detail of a marble bust; in the British Museum.

COURTESY OF THE TRUSTEES OF THE BRITISH MUSEUM

© 2006 Encyclopaedia Britannica, Inc.

trampoline ► transformer I 1931

sentative on earth. He strengthened defenses along the northern frontier and weakened the Praetorian Guard at Rome. He gave the Senate new authority, reduced taxes, supported the poor with government welfare, reformed provincial administration, and built public works, including a forum with Trajan’s Column, a structure commemorating his Dacian Wars. He added Dacia, Mesopotamia, and Parthia to the empire. He was campaigning in Asia when revolts broke out in conquered territories. Dis¬ couraged and ill, he died on his journey to Rome.

trampoline Resilient sheet or web (often of nylon) supported by springs in a metal frame and used as a springboard and landing area in tumbling. Trampolining is an individual sport of acrobatic movements performed after rebounding into the air from the trampoline. As a com¬ petitive sport, it was included in the Pan-American Games for the first time in 1955, and a world championship was established in 1964; com¬ petitors are scored on difficulty, execution, and form.

tranquilizer Drug used to reduce anxiety, fear, tension, agitation, and related disturbed mental states. Major tranquilizers (antipsychotic agents, or neuroleptics) are used to treat schizophrenia and other psychoses; phe- nothiazines, including chlorpromazine, are the best known. They are thought to block the activity of the neurotransmitter dopamine in the brain. Minor tranquilizers (antianxiety agents, or anxiolytics) are used to treat anxiety and tension; they are usually benzodiazepines, including diaz¬ epam (Valium) and chlordiazepoxide (Librium). They have a calming effect and reduce both physical and psychological effects of anxiety, fear, and stress by enhancing the action of the neurotransmitter gamma- aminobutyric acid (GABA) in the brain.

Trans-Alaska Pipeline or Alaska Pipeline Oil pipeline running 800 mi (1,300 km) north-south across Alaska, U.S. Completed in 1977, it transports crude oil from the oil fields of Prudhoe Bay on the Arctic Ocean to an ice-free port at Valdez. To avoid thawing the adjacent perma¬ frost, about half of the line is elevated.

Trans-Canada Highway World’s longest national road, extending east-west for 4,860 mi (7,821 km) between Victoria, British Columbia, and St. John’s, Newfoundland. Completed in 1965, it links many major Canadian cities and provides access to important national and provincial parks.

Trans-Siberian Railroad Longest single rail system in Russia, run¬ ning from Moscow to Vladivostok, a distance of 5,778 mi (9,198 km). Conceived by Tsar Alexander III, its construction began in 1891 and pro¬ ceeded simultaneously along its entire length, which traversed a section of Manchuria. It was completed in 1904, but the impending Japanese takeover of Manchuria compelled construction of a parallel section within Russian territory, completed in 1916. The railroad opened large areas of Siberia to settlement and industrialization by means of spur lines linking outlying areas with the main line. The complete trip takes about eight days.

Trans World Airlines, Inc. (TWA) Former U.S. airline acquired by the AMR Corp. Formed in 1930 as Transcontinental & Western Air, Inc., from two smaller airlines, the company established the first coast-to-coast service that same year, flying from Newark, N.J., to Los Angeles in 36 hours. In 1946 TWA began flights between New York City and Paris, and it expanded by the 1950s to routes through Europe, the Middle East, Africa, and Asia. It adopted its present name in 1950. Howard R. Hughes was its principal stockholder and guiding genius from 1939 to 1960-61, when he lost control to a group of investors. Financially troubled since the 1980s, TWA continued to operate despite twice landing in bankruptcy court in the 1990s. It was acquired by AMR, the parent company of American Airlines, in 2001.

transcendental argument In philosophy, a form of argument that is supposed to proceed from a fact to the necessary conditions of its pos¬ sibility. A transcendental argument is simply a form of deduction, with the typical pattern: Only if p then q; q is true; therefore, p is true. As this form of argument appears in philosophy, the interest, and the difficulty, reside not in the movement from premises to conclusions, which is rou¬ tine, but in the setting up of the major premises—that is, in the kinds of things that are taken as starting points. For example, Immanuel Kant tried to prove the principle of causality by showing that it is a necessary con¬ dition of the possibility of making empirically verifiable statements in natural science.

transcendental function In mathematics, a function not expressible as a finite combination of the algebraic operations of addition, subtrac¬ tion, multiplication, division, raising to a power, and extracting a root. Examples include the functions log x, sin x, cos x, e x and any functions containing them. Such functions are expressible in algebraic terms only as infinite series. In general, the term transcendental means nonalgebraic. See also transcendental number.

Transcendental Meditation (TM) Spiritual development technique developed and promoted by Maharishi Mahesh Yogi, a former Hindu ascetic. A movement that became popular in the West in the 1960s, it is based on specific meditation techniques and is not strictly connected with any religious tradition, though the perspective behind it has roots in Vedanta. Practice entails the mental repetition of a mantra in order to still the activity of thought and experience a deeper level of consciousness. Through this process, the practitioner finds deep relaxation, which can lead to inner joy, vitality, and creativity.

transcendental number Number that is not algebraic, in the sense that it is not the solution of an algebraic equation with rational-number coefficients. The numbers e and n, as well as any algebraic number raised to the power of an irrational number, are transcendental numbers.

Transcendentalism Movement of 19th-century New England phi¬ losophers and writers. The Transcendentalists were loosely bound together by adherence to an idealistic system of thought based on a belief in the essential unity of all creation, the innate goodness of humankind, and the supremacy of vision over logic and experience for the revelation of the deepest truths. Part of the Romantic movement (see Romanticism), it developed around Concord, Mass., attracting individualistic figures such as Ralph Waldo Emerson, Henry David Thoreau, AAargaret Fuller, and Bron¬ son Alcott. Transcendentalist writers and their contemporaries signaled the emergence of a new national culture based on native materials, and they were a major part of the American Renaissance in literature. They advocated reforms in church, state, and society, contributing to the rise of free religion and the abolition movement and to the formation of vari¬ ous utopian communities, such as Brook Farm. Some of the best writings by minor Transcendentalists appeared in The Dial (1840-44), a literary magazine.

transducer Device that converts one form of energy to another. A microphone is an acoustic transducer, converting sound waves into elec¬ trical signals. Different types of transducers act on heat, radiation, sound, strain, vibrations, pressure, and acceleration; they may output mechani¬ cal, electrical, pneumatic, or hydraulic signals. Examples include strain GAUGES, LOUDSPEAKERS, PHOTOCELLS, TRANSFORMERS, and THERMOCOUPLES.

transept Area of a cruciform (cross-shaped) church lying at right angles to the principal axis. The bay at which the transept intersects the nave is called the crossing. The nave of a church with a cruciform plan usually extends west from the crossing, the choir and sanctuary east. The arms of the transept are designated by direction, as northern transept and south¬ ern transept.

transform See Fourier transform, integral transform, Laplace transform

transformation In mathematics, a rule for changing a geometric fig¬ ure or algebraic expression into another, usually accompanied by a rule for transforming it back. In geometry and topology, a transformation (e.g., flipping horizontally or vertically, rotating, or stretching vertically or hori¬ zontally) moves each point in a figure or graph to another position. A graph also undergoes a transformation when its coordinate system is changed. For example, the equations that establish a correspondence between the rectangular and polar coordinate systems constitute a trans¬ formation. In analysis, a transformation is a procedure that changes one function into another. Of special interest in many fields of mathematics are transformations forming a group, in which any two transformations applied successively produce the same result as another transformation in the group and each transformation has an inverse transformation (which undoes it) in the group. See also group theory, integral transform, linear transformation.

transformer Device that transfers electric energy from one alternating- current circuit to one or more other circuits, either increasing (stepping up) or reducing (stepping down) the voltage. Uses for transformers include reducing the line voltage to operate low-voltage devices (door¬ bells or toy electric trains) and raising the voltage from electric genera¬ tors so that electric power can be transmitted over long distances.

© 2006 Encyclopaedia Britannica, Inc.

1932 I transfusion ► transsexualism

Transformers act through electromagnetic induction; current in the primary coil induces current in the secondary coil. The secondary voltage is cal¬ culated by multiplying the primary voltage by the ratio of the number of turns in the secondary coil to that in the primary.

transfusion See blood transfusion

transistor Solid-state semiconductor device for amplifying, controlling, and generating electrical signals. Invented at Bell Labs (1947) by John Bardeen, Walter H. Brattain, and William B. Shockley, it displaced the vacuum tube in many applications. Transistors consist of layers of differ¬ ent semiconductors produced by addition of impurities (such as arsenic or boron) to silicon. These impurities affect the way electric current moves through the silicon. Transistors were pivotal in the advancement of elec¬ tronics because of their small size, low power requirements, low heat generation, modest cost, reliability, and speed of operation. Single tran¬ sistors were superseded in the 1960s and ’70s by integrated circuits; present-day computer chips contain millions of transistors. Today transis¬ tors perform many different functions in nearly every type of electronic equipment.

transition element Any chemical element with valence electrons in two shells instead of only one. This structure gives them their outstand¬ ing ability to form ions containing more than one atom (complex ions, or coordination compounds), with a central atom or ion (often of a transi¬ tion metal) surrounded by ligands in a regular arrangement. Theories on the bonding in these ions are still being refined. The elements in the peri¬ odic table from scandium to copper (atomic numbers 21-29), yttrium to silver (39^17), and lanthanum to gold (57-79, including the ianthanide series) are frequently designated the three main transition series. (Those in the actinide series and beyond, 89-111, also qualify.) All are metals, many of major economic or industrial importance (e.g., iron, gold, nickel, titanium). Most are dense, hard, and brittle, conduct heat and electricity well, have high melting points, and form alloys with each other and other metals. Their electronic structure lets them form compounds at various valences. Many of these compounds are coloured and paramagnetic (see paramagnetism) and (as do the metals themselves) often act as catalysts. See also rare earth metal.

transitive law Property of relationship that states that if A is in a given relation to B and B is in the same relation to C, then A is also in that relation to C. Equality, for example, is a transitive relation.

Transkei Vtrans-'ka, 'trans-'kl\ Administrative region, South Africa. It borders the Indian Ocean and Lesotho. It was created by South Africa in 1959 as the first Bantu homeland, a nonindependent black state desig¬ nated (together with Ciskei) for the Xhosa-speaking peoples (see Xhosa). It was made a nominally independent republic in 1976, and all black Afri¬ cans with language ties to Transkei (whether or not they lived there) lost their South African citizenship and became citizens of the new country. Existing only as an element of the apartheid system, it never received international recognition. The region was reincorporated into South Africa in 1994 as part of Eastern Cape and KwaZulu-Natal provinces.

transmigration of souls See reincarnation

transmission System in an engine that transmits power generated by the engine to the point where it is to be used. Most mechanical transmis¬ sions function as rotary speed changers; the ratio of the output speed to the input speed may be either constant (as in a gearbox) or variable. On variable-speed transmissions, the speeds may be variable in individual steps (as on an automobile or some machine-tool drives) or continuously variable within a range. Step-variable transmissions, with some slip, usu¬ ally use either gears or chains and provide fixed speed ratios with no slip; stepless transmissions use belts, chains, or rolling-contact bodies. See illustration opposite.

transpiration Loss of water from a plant, mainly through the stomata (see stoma) of leaves. Darkness, internal water deficit, and extremes of tem¬ perature tend to close stomata and decrease transpiration; illumination, ample water supply, and optimum temperature cause stomata to open and increase transpiration. Its exact significance is disputed; its roles in pro¬ viding the energy to transport water in the plant and in aiding dissipation of the sun’s heat (by cooling through evaporation of water) have been chal¬ lenged. Since stomatal openings are necessary for the exchange of gases, transpiration has been considered by some to be merely an unavoidable phenomenon that accompanies the real functions of the stomata.

transplant or graft Partial or complete organ or other body part removed from one site and attached at another. It may come from the same or a different person or an animal. One from the same person—most often a skin graft—is not rejected. Transplants from another person or, espe¬ cially, an animal are rejected unless they are unusually compatible or have no blood vessels (e.g., the cornea), or if the recipient’s immune reaction is suppressed by lifelong drug treatment. Transplanted tissues must match (by blood tests) more closely than blood transfusions. Monoclonal antibodies targeting the cells that cause rejection hold great promise. Tests are now under way with monoclonal antibodies that react with antigens present only on T cells that are participating in rejection, sparing the rest. Rejection matters less in skin grafts, which may need to last only weeks, and bone grafts, whose structure remains after the cells die. In bone-marrow trans¬ plants, the donor’s marrow cells may attack the recipient’s tissues, often fatally. Lung transplants have greater chance of success as part of a heart- and-lung transplant. See also heart transplant, kidney transplant.

transport In biochemistry, the movement of molecules and particles across a cell membrane, a selective barrier that allows some substances (FAT-soluble molecules and some small molecules) to pass and blocks oth¬ ers (ions and large, water-soluble molecules). Transport of these vital sub¬ stances occurs via several systems. Open channels allow diffusion (passive transport) of ions directly into cells; facilitators use a chemical change to help substances diffuse past the membrane; “pumps” force dilute sub¬ stances through even when their concentration on the other side is higher (a form of active transport). Primary active transport is powered directly by energy released in cell metabolism (see ATP, adenosine triphosphate). In secondary active transport, a molecule is linked to a different molecule that carries it across the membrane (cotransport) or is exchanged for a different molecule crossing in the other direction (countertransport). The membrane itself opens and closes to let larger particles in or out.

Transport and General Workers' Union (TGWU) British labour union. The Dockers’ Union (founded 1889) took the lead in the merger of 14 unions to form the TGWU in 1922. The union grew rapidly under the leadership of Ernest Bevin (1922-40). As a general union it was able to enroll workers excluded by the craft unions, and its membership included workers engaged in transportation industries (except the rail¬ roads) as well as in the automotive, construction, chemical, and textile industries. It exerted a strong influence on British labour policy and was the largest British union during much of the 20th century, reaching a peak of more than two million members in the 1970s, though its membership declined thereafter. See also Labour Party; Trades Union Congress.

transsexualism Self-identification with one sex by a person who has the external genitalia and secondary sexual characteristics of the other sex. Early in life, such a person adopts the behaviour characteristic of the opposite sex. Surgery and hormone therapy now allow permanent sex change, a procedure first performed in 1952. The male-to-female opera¬ tion is more common because the genital reconstruction is more satisfac¬ tory. The male transsexual’s penis and testes are removed and an artificial vagina created; breasts are created with implants or female sex hormones.

A four-speed manual transmission. Power from the rotating input shaft turns the countershaft (or layshaft), which meshes with all four forward gears and the reverse gear on the output shaft. Which gear drives the output shaft is determined by the positions of the synchronizer assemblies, which are controlled by the gearshift stick (here, first gear is engaged). The unengaged gears simply revolve around the out¬ put shaft without transmitting power.

© MERRIAM-WEBSTER INC.

© 2006 Encyclopaedia Britannica, Inc.

transubstantiation ► treaty I 1933

Female transsexuals may undergo mastectomy and hormone treatments to produce male secondary sexual characteristics, but attempts to create an artificial penis have not been satisfactory.

transubstantiation In Christianity, the change by which the bread and wine of the Eucharist become in substance the body and blood of Jesus, though their appearance is not altered. This transformation is thought to bring the literal truth of Christ’s presence to the participants. The doctrine was first elaborated by theologians in the 13th century and was incorpo¬ rated into documents of the Council of Trent. In the mid-20th century, some Roman Catholic theologians interpreted it as referring to a change of meaning rather than a change of substance, but in 1965 Paul VI called for the retention of the original dogma.

transuranium element Any of the chemical elements after uranium in the periodic table (with atomic numbers greater than 92). All are radio¬ active (see radioactivity), with half-lives ranging from tens of millions of years to fractions of a millisecond. Only two, neptunium (93) and pluto¬ nium (94), occur in nature, and only as traces in uranium ores as a result of neutron irradiation. Transuranium elements with atomic numbers through 112, along with 114 and 116, have been produced in laboratories. Each appears to resemble the elements above it in the periodic table; in particular, the actinides, thorium (90) through lawrencium (103), are simi¬ lar to the lanthanides, cerium (58) through lutetium (71). The naming of the transuranium elements has been fraught with controversy regarding which laboratory first made the discovery and should propose the name and whether elements should be named for living persons. See also Glenn Seaborg.

Transvaal \trans-'val\ formerly (1856-77, 1881-1902) South Afri¬ can Republic Former province, northeastern South Africa. Located between the Limpopo and Vaal rivers, the region was inhabited c. 1800 chiefly by various Bantu- speaking peoples. The Boers (Afrikaners) began migrating there during the Great Trek of the 1830s. They established the short-lived South African Republic in 1856. Discoveries of diamonds and gold deposits (1868-74) heightened British interest in the region, and the British annexed the republic in 1877. A Boer rebellion restored it in 1881. Further discovery of gold in 1886 brought more foreigners, who eventu¬ ally outnumbered the Boers. In 1895 Leander Starr Jameson attempted to incite them to overthrow the Boer government. In 1899 Transvaal joined with Orange Free State against Britain in the South African (Boer) War. It was taken in 1900, and in 1902, following the British victory, it became a crown colony. It was granted self-government in 1906 and joined the Union (now Republic) of South Africa in 1910. In 1994 the Transvaal was split into four provinces. The region is extremely rich in mineral and agricultural resources.

Transylvania Historic region, northwestern and central Romania. It comprises a plateau surrounded by the Carpathian Mountains and the Tran¬ sylvanian Alps. It formed the nucleus of the Dacian kingdom and was included in the Roman province of Dacia in the 2nd century ad. The Mag¬ yars (Hungarians) conquered the area at the end of the 9th century. When Hungary was divided between the Habsburgs and the Turks in the 16th century, Transylvania became an autonomous principality within the Otto¬ man Empire. It was attached to Habsburg-controlled Hungary at the end of the 17th century. Transylvania was the scene of severe fighting in the Hungarian revolution against Austria in 1848. When Austria-Hungary was defeated in World War I, the Romanians of Transylvania proclaimed the land united with Romania. Hungary regained the northern portion during World War II, but the entire region was ceded to Romania in 1947.

Trapp family Austrian singers. Maria Augusta Kutschera (1905-87), the family’s best-known member, was an orphan and novitiate in a Bene¬ dictine convent in Salzburg. Later, as a governess, she won the hearts of the seven children of the widower Baron Georg von Trapp (18807-1947) and of the baron himself. They married in 1927, had three children, and later began singing German and liturgical music under the Reverend Franz Wasner, with whom the family fled in 1938 from Nazi-dominated Aus¬ tria to Italy, and finally to Stowe, Vt., U.S. They toured the world to great acclaim, disbanding in 1955. Their story was the subject of the musical The Sound of Music (1959; film, 1965).

trapshooting Shooting sport with moving targets. A shotgun (usually 12-gauge) is used. The targets are clay disks (called pigeons) that are sprung into the air from a trap. A later variant is skeet shooting. Trapshoot¬ ing’s origins date to the 18 th century, when marksmen shot at live pigeons released from cages or box traps. The modern clay-pigeon variety has

been included in Olympic Games competition since 1900. A single trap throws 25 targets at varying angles; each competitor fires four 25-target rounds.

Trasimeno X.tra-ze-'ma-noV Lake Lake, Umbria, central Italy. The larg¬ est lake of the Italian peninsula, it has an area of 49 sq mi (128 sq km) and is shallow, with a maximum depth of 20 ft (6 m). It is fed by small streams and has an artificial subterranean outlet (opened 1898) to the Tiber River. In 217 bc Hannibal defeated a Roman army led by Flaminius there in the Second Punic War. In World War II it was the scene of severe fight¬ ing (1944) between the British and German armies.

Travancore Vtra-v3n-,kor\ Former princely state, southwestern India. Now part of Kerala state, it was part of the kingdom of Kerala in the early centuries ad. In the 11th century it fell under the Cola empire; the Hindu kings of the Vijayanagar empire held it briefly in the 16th century, after which it came under Muslim rule. In the mid-18th century it became the independent state of Travancore; then it was under British protection from 1795. After Indian independence, it merged with Cochin to form the state of Travancore-Cochin; boundaries were redrawn, and it was renamed Ker¬ ala in 1956.

Traven Vtra-v3n\, B. (b. March 5, 18907, Chicago, Ill., U.S.7—d. March 27, 1969, Mexico City, Mex.) German-Mexican novelist. A recluse, he refused to disclose to publishers his parentage, nationality, and general identity, but he may have been forced to leave Germany for his partici¬ pation in its short-lived communist revolution in 1919. Most of his books were written in German. He is noted for adventure stories and as a chroni¬ cler of rural life in Mexico, where he settled in the 1920s. Among his novels are The Treasure of the Sierra Madre (1927; film, 1948) and a series tracing the lives of impoverished Indians in southern Mexico, including The Carreta (1931) and The Rebellion of the Hanged (1936). His works are harsh and his themes compelling, and his lean prose has a hypnotic immediacy. Much confusion remains about both his life and his authorship.

travertine \'tra-v9r-,ten\ Dense, banded rock composed of calcium car¬ bonate, CaC0 3 . Formed by rapid chemical precipitation of calcium car¬ bonate from solution in surface and ground waters, it is a variety of limestone that has a light colour and takes a good polish. It is often used for walls and interior decorations in public buildings and as a paving stone. Travertine is mined extensively in Italy; in the U.S., Yellowstone’s Mammoth Hot Springs are actively depositing travertine. It also occurs in limestone caves in the form of stalactites and stalagmites.

Travis, Merle (Robert) (b. Nov. 29, 1917, Rosewood, Ky., U.S.—d. Oct. 20, 1983, Tahlequah, Okla.) U.S. country music singer and songwriter. Travis learned banjo as a youth, later applying banjo technique to the gui¬ tar. He worked on radio in Cincinnati in the 1930s. Moving to California in 1944, he quickly rose to prominence on the strength of his guitar style and for writing and recording honky-tonk classics such as “Divorce Me C.O.D.” and “No Vacancy” and the coal-mining protest songs “Sixteen Tons” and “Dark as a Dungeon.”

treason Offense of attempting to overthrow the government of one’s country or of assisting its enemies in war. In the U.S., the framers of the Constitution defined treason narrowly—as the levying of war against the U.S. or the giving of aid and comfort to its enemies—in order to lessen the possibility that those in power might falsely or loosely charge their political opponents with treason. See also sedition.

treasury bill Short-term U.S. government security with maturities rang¬ ing from one month to 26 weeks. Treasury bills are usually sold at auction on a discount basis with a yield equal to the difference between the pur¬ chase price and the maturity value. Because they are highly liquid (money not being tied up in them for long periods of time), their yield rate is nor¬ mally lower than that of longer-term securities. Their prices do not usually fluctuate as much as those of other government securities but may be influ¬ enced by the purchase or sale of large quantities of bills by the central bank. First used extensively during World War I, treasury bills were initially regarded as an emergency source of revenue, but their flexibility and rela¬ tively low interest led to their adoption as a permanent element in the national debt. From 1970 to 1998 the minimum order for treasury bills was $10,000, after which it was reduced to $1,000. In 2001 the U.S. Treasury stopped offering treasury bills with maturities of 52 weeks.

treaty Contract or other written instrument binding two or more states under international law. The term is generally reserved for the more

© 2006 Encyclopaedia Britannica, Inc.

1934 I Trebbia River ► Trentino-Alto Adige

important international agreements, usually requiring, in addition to the signatures of authorized persons, ratification by the governments involved. A treaty may be bilateral or multilateral; it usually contains a preamble, an enumeration of the issues agreed on, and clauses that dis¬ cuss its ratification procedures, lifespan, and terms for termination. Trea¬ ties may be political, commercial, constitutional, or administrative, or they may relate to criminal and civil justice or codify international law.

Trebbia River \'treb-bya\ River, Emilia-Romagna region, northern Italy. Rising northeast of Genoa, it flows 71 mi (115 km) northeast across the northern Apennines and the Po lowland to enter the Po River. It was the scene of two notable battles: a Roman defeat by Hannibal in 218 bc, and a French defeat by a Russo-Austrian army in 1799.

Treblinka \tre-'blii]-ka\ German Nazi concentration camp during World War II. Located near the village of Treblinka, Pol., it opened in 1941 as a forced-labour camp. A larger and ultrasecret second camp a mile away, called T.II, opened in 1942 as an extermination camp for Jews. Victims were stripped and marched into “bathhouses,” where they were gassed with carbon monoxide from ceiling pipes. Ukrainian guards and up to 1,500 Jewish prisoner-workers performed the executions. The total num¬ ber killed has been estimated at 700,000 to 900,000. In 1943 a group of prisoner-workers rose in revolt and escaped, but most were soon killed or recaptured. The T.II camp was closed in October 1943, the labour camp in July 1944.

tree Woody perennial plant. Most trees have a single self-supporting trunk containing woody tissues, and in most species the trunk produces secondary limbs called branches. Trees provide many valuable products, especially wood, one of the world’s chief building materials, and wood pulp, used in papermaking. Wood is also a major fuel source. Trees sup¬ ply edible fruits and nuts. In addition, trees take in carbon dioxide and release oxygen during photosynthesis. Their root systems help retain water and soil, preventing floods and erosion. Trees and forests provide habi¬ tats for a wide variety of animals, and they beautify both natural and altered landscapes. Growth rings in the trunk indicate the age of most trees. The tallest trees are the Pacific coast redwoods; the oldest are the bristlecone pines, some of which are over 4,000 years old. See also coni¬ fer; deciduous tree; evergreen; forest; shrub; softwood.

Tree, Sir Herbert (Draper) Beerbohm (b. Dec. 17, 1853, Lon¬ don, Eng.—d. July 2, 1917, London) British actor-manager. A romantic actor with a gift for character roles and comedy, he made his London debut in 1878 and won favourable notice in The Private Secretary (1884). As manager of the Haymarket Theatre (1887-97), he directed and acted in lavish Shakespearean productions, which he continued as actor-manager of Her Majesty’s Theatre (1897-1915). He produced notable stage ver¬ sions of Charles Dickens’s works. In 1904 he founded the Royal Academy of Dramatic Ait.

tree fern Any of various ferns (especially those of the families Cyatheaceae and Marattiaceae) of treelike habit with a woody stem. Many attain heights over 50 ft (15.2 m). They are natives of humid moun¬ tain forests in the tropics and subtrop¬ ics and of warm temperate regions of the Southern Hemisphere. The fam¬ ily Marattiaceae contains six genera; one species, Angiopteris evecta, has leaves (fronds) 15 ft (4.5 m) or more in length and stems of 2-6 ft (60-180 cm). Now-extinct members of the family date to the Carboniferous Period (354-290 million years ago). Members of the family Cyatheaceae are very large, terrestrial ferns with trunklike, upright rhizomes; the nearly 1,000 species are grouped into seven genera.

tree frog or tree toad Any of

some 550 species (family Hylidae) of mostly arboreal frogs, found worldwide but primarily in the New World. Most species are small, slen¬

European green tree frogs (Hyla arborea ).

JANE BURTON/BRUCE COLEMAN LTD.

der, and long-legged and have suckerlike adhesive disks on the finger and toe tips. Some do not climb well and live in water, on land, or in a bur¬ row. Most species lay eggs in water. Young marsupial frogs (genus Gas- trotheca), of South America, develop in a brood pouch on the female’s back.

tree of heaven Rapid-growing tree ( Ailanthus altissima) in the quas¬ sia family (Simaroubaceae), native to China and widely naturalized else¬ where, with several known varieties. Because of its resistance to pollution, freedom from insect predation and disease, and ability to grow in almost any soil, the tree of heaven is planted as a yard and street tree in urban centres. It grows to 60 ft (18 m) or more, producing long, compound leaves that emit an unpleasant odour when bruised. Male trees bear flow¬ ers with unpleasant scents. Female trees produce winged fruits which are tannish orange when ripe.

Treitschke Vtrlch-koN, Heinrich von (b. Sept. 15, 1834, Dresden, Saxony—d. April 28, 1896, Berlin) German historian and political writer. Son of a Saxon general, Treitschke studied at Bonn and Leipzig and then taught history and politics at a number of German universities. A mem¬ ber of the Reichstag (1871-84), he advocated authoritarian rulers unchecked by a parliament and disparaged western European liberalism and American democracy. In 1886 he succeeded Leopold Ranke as official historiographer of Prussia. His major work is Treitschke’s History of Ger¬ many in the Nineteenth Century (1879-94).

Trek, Great See Great Trek

trematode See fluke