JACANA. 69 America (Jacana spinosa), abundant in Guiana and Brazil, is about 10 inches long; black, except the back and part of the wings, which are of a bright chestnut color. Another species {Jacana gymnostoma) is found in tropical America, and extends its range as far north as Texas. The prevailing color of the plumage is rich purplish chestnut. Their general habits are much like those of the gallinules, which they resemble in bodily appearance. The strong spur with which the bend of each wing is armed is a formidable weapon in the fighting that seems incessant among them. Of the ten or a dozen Old World species, one or two need special mention. The pheasant-tailed jacana . or "water-pheasant' (Hjidrophasianus chirurqus) is a familiar bird throughout the Oriental I'egion, and, like another species (of Northern Australia), is often called 'lotus-bird,' bfcause of its fondness for places where that plant prevails. Its colors are pleasing, and its tail is prolonged by four very long feathers, which suggest those of a pheasant. During the rains, in their favorite haunts, each pair forms a rudo flat nest of weeds and grass, interwoven beneath with the long shoots of aquatic plants, which support it buoyantly on the surface. All the family lay rich olive-brown eggs, closely niarkeil with dark lines. This bird is a favorite subject for representaticm in the native art of all tlie countries from India to Japan. The genus Metopedius, hardly different from the American jacana, has representatives in Africa, Madagascar, and India ; and the genus Hydro- lector belongs to Northern Australia and the neighboring islands. Consult authorities for South .merica. India, and the East, mentioned under Bird. See Plato nf Rails, etc. JACARAN'DA WOOD (Brazilian name). A hard, heavy, brown South American wood, which from its faint odor is also called rosewood. It is derived from several species of Jacaranda, of the natural order Rignoniaecfe. Several species locally called caruba, etc.. are employed medi- cinally in many South American countries. JACARi;, jak'a-ra'. Port. pron. zha'ka-ra' (Port, jricarc, jacareo, from the Brazilian name). Any of the caymans or alligators (qq.v.) of tropical America, the species of which are dis- tinguished by some qualifying word. Thus the 'jacare tinga' is the small six-foot Caiman frifio- vatiis. with the slender muzzle and black-banded tail: 'jacare nassu' is the great Caiman nifirr, sometimes '20 feet long. Used alone, the name usually means the 'common' cayman {Caiman srlerops). which is very numerous from Southern Mexico to Northern Argentina. It is of medium size, and is distinguished especially by the fact that the upper eyelid is rugose, partly ossified, and often produced into a small horn. All these alligators spread into the Hooded forests in the wet season and congregate in the river-courses during the dry season. They do vast damage to stock, and kill many human beings ; but their hides are of coiiimcrcial value, and their flesh is eaten by all the .mazonian Indians. JACCOTJD. zha'koTi'. Fran(;'ois Sigismond (18.30—). A French physician, born at Geneva. He went to Paris about l.S.'iO as a musie-teachcr : studied medicine, winning a gold tliedal in 1S.50. and his degree in ISfiO; and in 1863 became assistant in the medical faculty. He was ap- JACK. pointed titular professor in the Faculty of Medi- cine in 1876, member of the Academic de Medi- cine in 1877, and in 188.'5 began to teach in the medical clinic at the Pitie. He wrote: De I'organ- isatioii des facultes de medecine en Allemagne (1864), a report on his official investigation; Legmis de clinique medicale (1867-88); Traite de patholoffie interne (7th ed. 1883); Du froid connne cause de pneumonie (1887) ; and a trans- lation from Graves, Clinique medicale (1861-62) ; i.nd he edited the Nouveau dictionnaire de medi- cine et de chiriirgie (1864-86). JACHIN (ja'kin) AND BOAZ. The names of the two brazen pillars which Solomon set up in the porch of the temple (I. Kings vii. 15-21). JACHMANN", yiiG'man, Eduard Karl Ema- nuel ( 1822-87 ) . A German naval officer, born at Dantzic. In 1859-62 he took part in the expedi- tion to East Asia and China, and in 1864 de- feated the Danes near Jasmund, on the island of Riigen, whereupon he was promoted to be rear- admiral. Placed at the head of the T^Savy De- partment in 1867, he was made vice-admiral in the following year, and in the Franco-Ciemian ^^'ar was commander of the f4erman fleet in the North Sea. JACITARA (jas'l-ta'ra) PALM (South American Indian), De.imonci(s macroacanthos. A palm found in the lowland forests of the Ama- zon. It has a slender, flexible stem which of- ten climbs, by means of hooks, to a height of 60 or 70 feet. The outer part of the stem, cut into long strips, is much used to make the plaited cylinders in which grated cassava-root is squeezed in the process of extracting the starch. These wicker cylinders, which are very durable, will outlast two or three made from other fibres. The material seems suitable for many other purposes. JACK. A piece of mechanical apparatus for raising heavy weights short distances. Jacks are made in a variety of forms, but may be divided into screw jacks, hydraulic jacks and geared jacks. The screw jack or jack screw is so familiar a device that no description is neces- sary. Hydraulic jacks are portable forms of hydraulic presses. In geared jacks a combina- tion of levers and gearing takes the place of the screw of the screw jack and the water of the hydraulic jacks. The essential requirement of a jack is that it shall be of compact and sturdy construction and shall be conveniently portable. The ordinary screw jack is an excellent illustra- tion of all these qualities. See Hydraulic Press. JACK. In the United States Navy, a blue flag with white stars, corresponding in all respects to the similar portions of the national flag, which is sometimes called the union. In Great Britain and Germany the jack is a flag which is similar to the upper quarter of the man-of-war flag which is nearest the .staff. In countries which have no union in their man-of-war flag, the jack more nearly resembles the colors carried at the stern e>?cept in size. It is set on a staff at the stem, or on the bowsprit cap of rigged ships. It has no particular significance at the present time, but is usually hoisted in port, except when coaling ship, or when similar work is going on. JACK, or JACKFISH. A name applied, often in connection with some qualifying word, to
