dithyramb \'dith-i-,ram(b)\ Choric poem, chant, or hymn of ancient Greece. Dithyrambs were sung by revelers at the festival in honour of Dionysus. The form originated about the 7th century bc in extemporane¬ ous songs of banqueters; it was a recognized literary genre by the end of the 6th century bc. Dithyrambs were composed by Arion and Pindar, among others. By c. 450 bc the form was in decline; most dithyrambs were bombastic and turgid.
Differs von Dittersdorf Vdit-ors-.dorft, Carl orig. Carl Differs (b.
Nov. 2, 1739, Vienna, Austria—d. Oct. 24, 1799, Rothlhotta Castle, Neu- hof, Bohemia) Austrian composer. A violin prodigy, he served as kapell¬ meister at the court of the prince-bishop of Breslau (1770-95). Though ennobled by the empress in 1773, he apparently declined the offer of the post of kapellmeister at the imperial court in Vienna. Extremely prolific, he wrote some 120 symphonies, some 40 concertos (many for violin), sacred choral works, and many chamber pieces. Most important are some 40 stage works, particularly his singspiels, including Doctor und Apotheker (1786) and Die Liebe im Narrenhause (1787).
diuretic \,dl-yur-'e-tik\ Any drug that increases the flow of urine from the body. Diuretics promote removal of excess water, salts, poisons, and metabolic wastes to help relieve edema, kidney failure, or glaucoma. Most types act by decreasing the amount of fluid that is reabsorbed by the kid¬ ney’s nephrons and passed back into the blood. Diuretics that allow the body to retain potassium are used for patients with hypertension or conges¬ tive HEART FAILURE.
Divali or Diwali Vdo-'wa-le, d3-'va-le\ In Hinduism, a five-day religious festival in autumn. It honors Lakshmi, goddess of wealth, or, in Bengal, the goddess Kali. During its celebration, earthenware lamps are lit and placed on the parapets of houses and temples or set adrift on rivers and streams. The fourth day of the festival marks the start of a new year, a time of gift-giving, visiting friends, decorating homes, and wearing new clothes. Divali is celebrated by Jains and Sikhs as well.
diver See loon
divergence In mathematics, a differential operator applied to a three- dimensional vector-valued function. The result is a function that describes a rate of change. The divergence of a vector v is given by
div v =
dvi
dx
dll . d_y dz
in which v l5 v 2 , and v 3 are the vector components of v, typically a veloc¬ ity field of fluid flow.
diverticulum X.dl-vor-'ti-kyo-bmX Small pouch or sac formed in the wall of a major organ, usually the esophagus, small intestine, or large intes¬ tine (the most frequent site of problems). In the large intestine, feces pushed into a pouch can make it bulge out from the colon wall, a con¬ dition known as diverticulosis, which has no symptoms. In the more seri-
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554 I divertimento ► Dixieland
ous condition called diverticulitis, those sacs become inflamed, causing pain and tenderness, chills, and sometimes fever. Mild cases need only bed rest and antibiotics. In severe cases, perforation or rupture of the colon wall at the diverticulum can cause peritonitis. Rupture may require colos¬ tomy. Meckel diverticulum, a congenital malformation of the upper intes¬ tine that causes bleeding and inflammation, may require surgical removal.
divertimento Xdi-.vor-ti-'men-toN Eighteenth-century chamber music genre consisting of several movements, often of a light and entertaining nature, for strings, winds, or both. Though the name was applied (c. 1750-1800) to a confusingly varied range of works, it almost always referred to pieces with a single instrument to a part; this could include string quartets and even keyboard sonatas.
dividend Individual share of earnings distributed among stockholders of a corporation or company in proportion to their holdings. Usually paid in cash, dividends may also be distributed in the form of additional shares of stock. Preferred stockholders receive a preferential dividend, usually at a fixed rate; common stockholders get a portion of what remains after payment of the dividends on preferred stock.
dividing engine Machine used to mark off equal intervals accurately, usually on precision instruments. Georg Friedrich von Reichenbach (1772-1826), a German maker of astronomical instruments, designed an early dividing engine, and Jesse Ramsden (1735-1800), a British pioneer in the design of precision tools, designed dividing engines of great accu¬ racy for both circles and straight lines and produced highly accurate sex¬ tants, theodolites (see surveying), and vertical circles for astronomical observatories.
divination Practice of discerning the hidden significance of events and foretelling the future. Divination is found in all societies, ancient and modern, though methods vary. In the West, psychics claim innate ability to predict the future, and horoscopes, palm reading, and tarot cards are popular methods of divination. Other methods involve or have involved interpreting dreams, discovering omens in natural events, reading the entrails of animals, casting lots, and consulting oracles. Divination has long been viewed as the province of specially gifted persons, such as prophets, shamans, and magicians. See also astrology.
Divine, Father orig. George Baker (b. 1880?, Georgia?, U.S.—d. Sept. 10, 1965, Philadelphia, Pa.) U.S. religious leader. Reportedly born on a plantation, he began preaching in 1899 in the South and later in Bal¬ timore, Md., as “The Messenger.” He settled in New York City in 1915 and adopted the name Major J. Devine (later altered to Father Divine). In 1919 he established his first communal settlement in Sayville on Long Island, and he founded the Peace Mission movement. His predominantly black following expanded rapidly in the 1930s and ’40s, and his settle¬ ments, called “heavens,” eventually numbered about 170. He taught his followers to renounce personal property, and the strict moral code he preached included celibacy and a ban on alcohol and tobacco. Many of his followers, called “angels,” believed him to be God.
divine kingship Religio-political concept that views a ruler as an incarnation, manifestation, mediator, or agent of the sacred. In some non¬ literate societies, members view their rulers or chiefs as inheritors of the community’s own magical power. The ruler may exercise this power either malevolently or benevolently, but he is usually responsible for influ¬ encing the weather and the land’s fertility to ensure the harvest necessary for survival. In other societies, particularly those of ancient China, the Middle East, and South America, the ruler was identified with a particu¬ lar god or as a god himself; in Japan, Peru (among the Inca), Mesopot¬ amia, and the Greco-Roman world, the ruler was regarded as the son of a god. In either case—whether the ruler embodies his own magical power or that of the community—the ruler protects the community from enemies and generally feeds and cares for his people. A third form of divine king- ship, one practiced in Europe, is that of the ruler as mediator or execu¬ tive agent of a god. In this form it is the institution of kingship, more than an individual ruler, that bears the mark of the sacred.
diving Sport of plunging into water, usually headfirst and often follow¬ ing the execution of one or more acrobatic maneuvers. It emerged as a competitive sport in the late 19th century and became part of the Olym¬ pic Games in 1904. Dives are performed from a firm platform 5 or 10 m (16.4 or 32.8 ft) above the water, or from a springboard 1 or 3 m (3.3 or 9.8 ft) above the water. In Olympic contests, only the 10-m platform and 3-m springboard are used. Contestants are required to do certain dives,