jet stream Any of several long, narrow, high-speed air currents that flow eastward in a generally horizontal zone in the stratosphere or upper troposphere. Jet streams are characterized by wind motions that generate strong vertical shearing action, considered largely responsible for the clear-air turbulence experienced by aircraft. They also have an effect on weather patterns. Jet streams circle the Earth in meandering paths, shift¬
ing position as well as speed with the seasons. In the winter they are nearer the Equator and their speeds are higher than in the summer. There are often two, sometimes three, jet-stream systems in each hemisphere.
Jew Any person whose religion is Judaism. In a wider sense the term refers to any member of a worldwide ethnic and cultural group descended from the ancient Hebrews who traditionally practiced the Jewish religion. The Hebrew term Yehudi, translated as Judaeus in Latin and Jew in English, originally referred to a member of the tribe of Judah. In Jewish tradition, any child born of a Jewish mother is considered a Jew; in Reform Judaism a child is considered a Jew if either parent is Jewish.
Jewel Cave National Monument National monument, southwest¬ ern South Dakota, U.S. Established in 1908, it occupies an area of 2 sq mi (5 sq km). It is noted for its limestone caverns, a series of chambers joined by narrow passages. The known length of the caverns is 77 mi (124 km).
jewelry Objects designed for the adornment of the body, usually made of gold, silver, or platinum, often with precious or semiprecious stones and such organic substances as pearls, coral, and amber. Jewelry evolved from shells, animal teeth, and other objects used as adornment in prehis¬ toric times. Over the centuries it came to be a sign of social or religious rank. In Renaissance Italy, jewelry making reached the status of a fine art; many Italian sculptors trained as goldsmiths. From the 17th century the decorative function of jewelry again came to the fore, overshadowing its symbolic significance. By the 19th century, industrialization brought jew¬ elry within the reach of the middle class. Firms opened by jewelers such as Carl Faberge and Louis Comfort Tiffany achieved great success by mak¬ ing fine jewelry for the wealthy.
Jewett, (Theodora) Sarah Orne (b. Sept. 3, 1849, South Berwick, Maine, U.S.—d. June 24, 1909, South Berwick) U.S. writer. Concerned to capture the folkways of a vanishing culture, she wrote realistic sketches of aging Maine natives, whose manners, idioms, and pithiness she recorded with pungency and humour. Outstanding among her 20 volumes are Deephaven (1877), A White Heron (1886), and The Country of the Pointed Firs (1896).
jewfish Any of several large fishes of the sea bass family (Serranidae), especially Epinephelus itajara, found on the Atlantic coast of the New World tropics. They may reach a length of 8 ft (2.4 m) and a weight of about 700 lbs (320 kg). The adult is dull olive-brown with faint spots and bands and is usually solitary. The South Pacific jewfish {E. lanceolatus) may exceed 12 ft (3.7 m) in length. The Warsaw grouper ( E . nigritus) and giant sea bass ( Stereolepis gigas) are both occasionally called jewfish, and three Australian species in the genera Johnius and Glaucosoma are called jewfish.
Jewish calendar See Jewish calendar
Jewish philosophy Any of various kinds of reflective thought engaged in by those identified as being Jews. In the Middle Ages, this meant any methodical and disciplined thought pursued by Jews, whether on specifically Judaic themes or not; in modern times, philosophers who do not discuss Judaism are not ordinarily classified as Jewish philoso¬ phers. Philosophy arose in Judaism under Greek influence, though a philo¬ sophical approach may be discerned in early Jewish religious works apparently uninfluenced by the Greeks. From the Bible, the books of Job and Ecclesiastes were favourite works of medieval philosophers; the book of Proverbs introduces the concept of Wisdom ( Hokhma ), which was to have primordial significance for Jewish philosophical thought; and the Wisdom of Solomon had considerable influence on Christian theology. Major figures of Jewish philosophy include Philo Judaeus, Saadia ben Joseph, Moses Maimonides, and Benedict de Spinoza.
Jezebel Yje-za-,bel\ (d. c. 843 bc) In the Hebrew scriptures, the wife of King Ahab of Israel. The daughter of the priest-king Ethbaal of Tyre and Sidon, she persuaded Ahab to introduce the worship of the Tyrian god Baal-Melkart into Israel, thus interfering with the exclusive worship of Yahweh. The book of 1 Kings tells how she was opposed by Elijah. After Ahab’s death Jezebel’s son Jehoram became king of Israel, but Elisha encouraged a general, Jehu, to revolt. Jehoram was killed, and Jezebel was thrown from a window to her death. Dogs consumed most of her body, fulfilling a prophecy by Elijah. In history and literature she became the archetype of the wicked woman.
Jhabvala Vjab-va-b\, Ruth Prawer orig. Ruth Prawer (b. May
7, 1927, Cologne, Ger.) German-born British-U.S. novelist and screen-
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writer. Bom to a family of Polish Jews, she immigrated to England with her family in 1939. She married an Indian architect and moved to India, where she lived until 1975. Thereafter she lived in New York. Many of her novels, including Heat and Dust (1975, Booker Prize), are set in India. She has written original screenplays for such films as Shakespeare-Wallah (1965) and film adaptations of such novels as The Bostonians (1984), A Room with a View (1985), Howards End (1992), The Remains of the Day (1993), and The Golden Bowl (2000).
Jharkhand State (pop., 2001 prelim.: 26,909,428), northeastern India. It is bordered by Bihar, West Bengal, Orissa, Chhattisgarh, and Uttar Pradesh states and occupies 28,833 sq mi (74,677 sq km); its capital is Ranchi. The state lies mainly on the Chota Nagapur Plateau, a series of plateaus, hills, and valleys. Many aboriginal peoples live there. The area now constituting Jharkhand was a part of Bihar state after Indian inde¬ pendence in 1947 until it was made into a separate state in 2000. It is rich in minerals (notably copper), although most of the population is engaged in agriculture.
Jhelum Vja-lomV River River, India and Pakistan. The westernmost of the “Five Rivers” of the Punjab region, it rises in the Himalayas in the Indian state of Jammu and Kashmir. It meanders northwest in the Pakistani- administered sector of the Kashmir region. Bending southward, it joins the Chenab River, having traveled a course of 450 mi (725 km). It is believed to be the Hydaspes mentioned by Arrian, Alexander the Great’s historian, and the Bidaspes mentioned by Ptolemy.
Jhering \'ya-riq\, Rudolf von (b. Aug. 22, 1818,Aurich, Hanover—d. Sept. 17, 1892, Gottingen, Ger.) German legal scholar. He taught Roman law at Giessen (1852-68), at Gottingen (from 1872), and at four other universities (including the University of Vienna) for briefer periods. He examined the relationship between law and social change in The Spirit of Roman Law (1852-65) and between individual and social interests in Law as a Means to an End (1877-83). He maintained that the purpose of law is to protect individual and societal interests by coordinating them and thus minimizing occasions for conflict. He is sometimes called the father of sociological jurisprudence.
Jia Xian (fl. c. 1050, China) Mathematician and astronomer active at the beginning of the greatest period of traditional Chinese mathematics. He held a relatively low military office during the reign (1022/23-1063/ 64) of Emperor Renzong of the Song dynasty. He was a pupil of math¬ ematician and astronomer Chu Yan, who contributed to the revision of the Chongtian calendar in 1023, and he served in the Imperial Astronomical Bureau. Jia’s name was mainly quoted in connection with his method of extracting roots (solutions) of polynomials of degree higher than three and with the related Jia Xian triangle, which contains the binomial coefficients for equations up to the sixth degree (see binomial theorem). This diagram is similar to Blaise Pascal’s triangle, which was discovered independently later in the West.