pylon \'pl-,lan\ (Greek: “gateway”) In modem construction, a tower that gives support, such as the steel towers between which electrical wires are strung or the piers of a bridge. Originally, pylons were monumental gate¬ ways to ancient Egyptian temples, either a pair of tall truncated pyramids with a doorway between them or a masonry mass pierced by a doorway.
Pym \'pim\, John (b. 1583/84, Brymore, Somerset, Eng.—d. Dec. 8, 1643, London) English politician. As a member of Parliament (1621-43), he soon became an expert on finances and colonial affairs. He was an architect of Parliament’s victory over Charles I in the first phase of the English Civil Wars. He helped form the system of taxation that survived in England until the 19th century. His skill as a parliamentary tactician preserved the unity of Parliament and led to close relations between the government and the city of London.
Pynchon Vpin-chonV Thomas (b. May 8, 1937, Glen Cove, Long Island, N.Y., U.S.) U.S. writer. He studied physics at Cornell University and worked briefly as a technical writer before devoting himself to fic¬ tion. Beginning with his first novel, V (1963), a complex, cynically absurd tale that juxtaposes scenes of 1950s hipster life with symbolic images of the entire century, his works have combined black humour and fantasy to depict human alienation in the chaos of modem society. The idea of con¬ spiracy is central to The Crying of Lot 49 (1966) and to his masterpiece, Gravity’s Rainbow (1973), an extraordinary novel about the end of World War II, full of paranoid fantasy, grotesque imagery, and esoteric scientific and anthropological material. Later works include the novels Vineland (1990) and Mason & Dixon (1997) and the story collection Slow Learner (1984). He has lived in hiding or incognito for decades, refusing to grant interviews or be photographed.
P'ydngyang \ 1 pyoq- , yai]\ City (pop., 2003 est.: 3,164,000), capital of North Korea, on the Taedong River. Founded in 1122 bc according to leg¬ end, it is said to be the oldest city in Korea. In 108 bc the Chinese estab¬
lished a trading colony there. It was the capital of the Koguryo kingdom (ad 427-668), then was captured by Chinese invaders. It fell to the Japanese in 1592 and was devastated by the Manchus in the early 17th century. Much of it was destroyed during the Sino-Japanese War (1894-95). During the Japanese occupation of Korea (1910—45), it was built up as an industrial city. Captured by UN forces during the Korean War in 1950, it was retaken by Chinese communist troops. After 1953 it was rebuilt with Soviet and Chinese aid. It is a centre of heavy industry and transportation.
pyramid Ancient monumental structure constructed of or faced with stone or brick and having a rectangular base and four sloping triangular sides meeting at an apex. Pyramids have been built at various times and places; the best-known are those of Egypt and of Central and South America. The pyramids of ancient Egypt were royal tombs. Each con¬ tained an inner sepulchral chamber that housed the deceased (usually mummified) ruler, members of his entourage, and artifacts. The rest of the pyramid complex consisted of a large enclosure, an adjacent mortuary temple, and a causeway leading down to a pavilion. About 80 royal pyra¬ mids survive in Egypt, the greatest being those at Giza. American pyra¬ mids include the pyramids of the Sun and Moon at Teotihuacan, the Castillo at Chichen Itza, and various Inca and Chimu structures in Andean settlements. These pyramids were generally built of earth and faced with stone; they are typically stepped pyramids and are topped by a platform or temple structure used for rituals, including human sacrifice.
Pyramus and Thisbe Vpir-9-m9s... , thiz-be\ Hero and heroine of a Babylonian love story related in Ovid’s Metamorphoses. Their parents forbade them to meet, so they communicated through a hole in the wall between their two houses before at last deciding to run away together. They agreed to meet at a mulberry tree. Arriving first, Thisbe was scared away by a lion, which shredded the veil she dropped when she fled. Pyra¬ mus, finding the veil, believed her dead and stabbed himself; she returned and, finding Pyramus dying, killed herself. The fruit of the mulberry tree, white until then, was stained dark purple by the lovers’ blood.
Pyrenees \'pir-9-,nez\ Mountain range, southwestern Europe. It extends 270 mi (430 km) from the Mediterranean Sea to the Bay of Biscay on the Atlantic Ocean. The Pyrenees form a high wall between France and Spain; generally, the crest of the range marks the boundary between the two countries. The tiny, autonomous principality of Andorra lies among the range’s peaks. The highest point is Aneto Peak, elevation 11,169 ft (3,404 m). There are few passes through the mountains. The pass at Roncesvalles was made famous in the 12th-century La Chanson de Roland, based on the 778 Battle of Roncesvalles (Roncevaux).
Pyrenees, Treaty of the (November 7, 1659) Peace treaty between France and Spain. From the end of the Thirty Years' War (1648) until 1659, Spain and France fought almost continuously. When Philip IV of Spain did not receive the expected Habsburg support against France, he concluded a peace settlement that ceded border regions to France. The treaty also involved a marriage compact between Louis XIV and the Spanish infanta Maria Teresa, which established Louis as the most powerful monarch in Europe.
pyrethrum \pl-'re-thr9m\ Any of certain plant species of the genus Chrysanthemum (see chrysanthemum) native to South Asia, whose aro¬ matic flower heads, when powdered, constitute the active ingredient in the insecticide pyrethrin (or py rethrum). The concentrations of pyre thrum powder used in insecticides are nontoxic to plants and higher animals; these insecticides therefore find wide use in household and livestock sprays as well as in dusts for edible plants. The typical species, the peren¬ nial C. coccineum, also is the florists’ pyrethrum, or painted lady. Large petals of a deep rose colour surrounding the yellow centre, or disk, are borne on long simple stems above the crown of finely cut leaves.
pyridine \'pir-3-,den\ Any of a class of aromatic compounds with a six- member aromatic ring composed of five carbon atoms and one nitrogen atom, making it a heterocyclic compound. The simplest one is pyridine itself (C 5 H 5 N). Natural compounds with pyridine rings include niacin and pyridoxine (see vitamin B complex), the tuberculosis drug isoniazid, and sev¬ eral plant products (e.g., nicotine). Pyridine is used as a raw material for various drugs, vitamins, and fungicides and as a solvent. Because it has a nauseating odour and a burning taste, it is added to ethanol and anti¬ freezes to make them undrinkable (see denaturation).
pyrimidine \p3-Tim-3-,den\ Any of a class of heterocyclic compounds with a ring structure of four carbon and two nitrogen atoms. The simplest
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1570 I pyrite ► python
member, pyrimidine itself (C 4 H 4 N 2 ), is not common, but derivatives with the structure are. Examples include thiamine (vitamin Bj), several sulfa drugs, barbiturates, and three of the bases in nucleic acids (cytosine, thym¬ ine, and uracil).
pyrite \'pi-.rit\ or iron pyrite or fool's gold Naturally occurring, gold-coloured iron disulfide mineral. Pyrite has frequently fooled prospec¬ tors into thinking they had discovered gold. Pure pyrite (FeS 2 ) contains 47% iron and 53% sulfur, by weight. Pyrite is used commercially as a source of sulfur, particularly for the production of sulfuric acid. Because there are much better sources of iron, it is not generally used as an iron ore. For many years Spain was the largest producer; other countries include Japan, the U.S., Canada, Italy, Norway, Portugal, and Slovakia.