Jacquard \'ja-,kard\ loom Loom incorporating a special device to con¬ trol individual warp yarns. It enabled production of fabrics with intricate woven patterns such as tapestry, brocade, and damask, and has also been adapted to the production of patterned knitted fabrics. Developed in France by J.-M. Jacquard in 1804-05, it used interchangeable punched cards that controlled the weaving of the cloth so that any desired pattern could be obtained automatically. It aroused bitter hostility among weav¬ ers, who feared that its labour-saving capabilities would deprive them of jobs; the weavers of Lyon not only burned the machines but attacked Jac¬ quard as well. Eventually the loom’s advantages led to its general accep¬ tance, and by 1812 there were 11,000 in use in France. Use of the loom spread to England in the 1820s and from there virtually worldwide.
Jacui \zha-'kwe\ River River, southern Brazil. It rises in the hills east of Passo Fundo and flows southward and eastward for 280 mi (450 km). At Porto Alegre it receives four other rivers and forms the Guaiba River, a shallow estuary that empties into the Atlantic Ocean. Navigable upstream as far as Cachoeira do Sul, it has one of the most heavily used river barge systems in Brazil.
jade Either of two tough, compact, typically green gemstones that take a high polish. Both have been carved into jewelry, ornaments, small sculp¬ tures, and utilitarian objects from earliest recorded times. The more highly prized of the two jadestones is jadeite; the other is nephrite. Both types may be white or colourless, but colours such as red, green, and gray may occur.
jadeite Vjad-,It\ Gem-quality sili¬ cate mineral in the pyroxene family that is one of the two forms of jade.
Jadeite (imperial jade), sodium alu¬ minum silicate (NaAlSi 2 0 6 ), may contain impurities that give it a vari¬ ety of colours: white, green, red, brown, and blue. The most highly prized variety is emerald green.
Jadeite occurs only in metamorphic rocks, most often in those that have
been subjected to the high pressures deep below the Earth’s surface. The area around the city of Mogaung in northern Myanmar has long been the main source of gem-quality jadeite.
jaeger \'ya-gor\ Any of three species (genus Stercorarius, family Ster- corariidae) of seabirds. They resemble dark gulls with a forward- set black cap and projecting central tail feathers. Jaegers have two colour phases: all brown or (more com¬ monly) brown above and white below. They nest in the Arctic tundra and then go to sea, many as far as Australia and New Zealand. At sea they catch fish on their own, but, while nesting along coasts, they force terns and kittiwakes to disgorge their food, destroy the eggs and young of other seabirds, and capture land birds and rodents. The species range from 14 to 20 in. (35 to 50 cm) long. In Great Britain, jaegers are called skuas.
Ja'far ibn Muhammad \ , ja-far- 1 i-b3n-mu-'ha-m3d\ (b. 699/700, Medina, Arabia—d. 765, Medina) Sixth imam of the Shiite branch of Islam and the last to be recognized by all the Shfite sects. He was the great- grandson of 'All As a possible claimant to the caliphate, Ja'far was viewed as a threat to both the Umayyad and 'Abbasid dynasties. He traveled to Baghdad in 762 to prove to the caliph that he was not seeking power, then returned to his native Medina, where his pupils included Abu HanTfah. After his death the Shl'ites began to splinter. One sect, the Isma'iliyyah, became followers of his son, Ismail. Another, the Ithna 'Ashariyyah, traced a succession from Ja'far to the Twelfth Imam awaited at the Last Judg¬ ment.
Jaffa See Tel Aviv-Yafo
Jagannatha Vjs-go-.nat-oX or Jagannath Form under which Krishna is worshiped at Puri, Orissa, a famous religious center of India. His temple at Puri dates from the 12th century. The Rathayatra, or Chariot Festival, is held in his honor each year in June or July. An image of the god is placed on a cart so heavy that it takes thousands of devotees several days to move it to the god’s temple outside the city. According to legend, pil¬ grims sometimes throw themselves under the wagon in hopes of attain¬ ing instant salvation, a practice that gave rise to the English word juggernaut.
Jagiello I See Wladislaw II Jagiello
Jagiellon \yag-'ye-lon\ dynasty Family of monarchs of Poland- Lithuania, Bohemia, and Hungary that became one of the most powerful in east-central Europe in the 15th-16th centuries. It was founded by Jogaila, grand duke of Lithuania, who became Wladyslaw II Jagiello of Poland after marriage to Queen Jadwiga (13737-99) in 1386. Wladyslaw III Wamenczyk (1424-44) extended the dynasty by also assuming the throne of Hungary (1440). He was succeeded by Casimir IV, who placed his son on the thrones of Bohemia (1471) and Hungary. During the reigns of Casimir’s sons John Albert (1459-1501) and Alexander (1461-1506), the Jagiellon rulers lost much of their power in Poland to the nobility. When Sigismund I succeeded Alexander in 1506, he strengthened the gov¬ ernment and saw the Teutonic Order convert its lands into the secular duchy of Prussia (1525), a Polish fief. In 1526 the death of Louis II ended Jagiellon rule in Bohemia and Hungary. In 1561 Sigismund II Augustus incorporated Livonia into Poland, but when he died, leaving no heirs, the Jagiellon dynasty ended (1572).
jagirdar \j3-'gir-,dar\ system Form of land tenancy introduced in India by the early sultans of Delhi in the early 13th century. Under the system, land, its revenues, and the power to govern it was assigned to an official of the state. The land reverted to the government on the official’s death, but heirs could renew the land assignment by paying a fee. Feu¬ dalists in character, the jagirdar system tended to enfeeble the central government by setting up quasi-independent baronies. Periodically abol¬ ished, it was always renewed. After Indian independence, measures were taken to abolish absentee landownership.
jaguar Largest New World cat. Once found in wooded regions from the U.S.-Mexican border south to Patagonia, the jaguar (Panthera onca ) sur¬ vives, in reduced numbers, only in remote areas of Central and South
Dragon among clouds, carved jade medallion or button, Ch'ing dynasty, probably late 18th century (reign of Ch'ien-lung); in the Victoria and Albert Museum, London
COURTESY OF THE BOARD OF TRUSTEES OF THE VICTORIA AND ALBERT MUSEUM, LONDON, WELLS LEGACY
Uncut (left) and cut jadeite
RUNK/SCHOENBERGER-GRANT HEILMAN
Long-tailed jaeger (Stercorarius longi- caudus).
© ALAN WILLIAMS/NHPA
© 2006 Encyclopaedia Britannica, Inc.
Jaguaribe ► Jamaica i 975
America; the largest known population is in the Amazon rain forest. The male is 5.5-9 ft (1.7-2.7 m) long, including the 23-35-in. (60-90-cm) tail, and weighs 220-350 lbs (100-160 kg). The coat is typically orange- tan with black spots arranged in rosettes having a black spot in the cen¬ tre. A solitary predator, the jaguar usually hunts rodents, deer, birds, and fish; it will also take cattle, horses, and dogs.
Jaguaribe \,zha-gwa-'re-be\ River River, northeastern Brazil. Formed by the junction of the Carapateiro and Trici rivers, it flows northeastward for 350 mi (560 km) to enter the Atlantic Ocean at Aracati. Long periods of drought, during which much of the river is dry, are followed by cata¬ strophic floods that inundate the towns along its lower course.
Jahangir Vjo-'han-geAo; Jehangir (b. Aug. 31,1569, Fatehpur, Sikri, India—d. Oct. 28, 1627, en route to Lahore) Mughal emperor of India (1605-27). Though designated heir apparent, the impatient Jahangir revolted in 1599; his father, Akbar, nevertheless confirmed him as his suc¬ cessor. Like Akbar, Jahangir managed diplomatic relations on the Indian subcontinent adroitly, was tolerant of non-Muslims, and was a great patron of the arts. He encouraged Persian culture in Mughal India. During the middle portion of his reign, politics were dominated by his Persian wife (Nur Jahan), her father, and Jahangir’s son Prince Khurram (the future Shah Jahan).