Pishpek See Bishkek
Pisidia \pi-'si-de-o\ Ancient region, southern Anatolia. Most of it was composed of the Taurus Mountains, which provided refuge for a lawless population that resisted successive conquerors. It was incorporated into the Roman province of Galatia in the early 1st century ad and became
part of Lycia and Pamphylia under the emperor Vespasian in ad 74. Dio¬ cletian included Pisidia in the diocese of Asia c. 297. During Byzantine times it continued to be a region of revolt. By 1204 the Byzantine Empire had lost control of the region to Turkish invaders.
pistachio \p3-'sta-she-,o\ Any of nine species of aromatic trees and shrubs, some ornamental, that make up the genus Pistacia of the sumac (or cashew) family, native to Eurasia, with one species in southwestern North America and another in the Canary Islands. Commercial pistachio nuts are seeds from the fruit of P. vera. They have a pleasing, mild, res¬ inous flavour and are used extensively as food and for yellowish green colouring in confections. The tree bears leaves with thick, wide, leathery, featherlike leaflets and small fruit in clusters.
pistil Female reproductive part of a flower. Centrally located, the pistil typically has a swollen base called the ovary, which contains the poten¬ tial seeds (ovules). The stalk (style) arises from the ovary and has a pollen- receptive tip, the stigma, which is variously shaped and often sticky. There may be a single pistil, as in the lily, or several to many pistils, as in the buttercup. Each pistil is constructed of one to many rolled leaflike struc¬ tures, or carpels. Differences in the composition and form of the pistil are useful in classifying flowering plants. See also stamen.
pistol Small firearm designed to be operated with one hand. The name may derive from the city of Pistoia, Italy, where handguns were made as early as the 15th century. It was originally a cavalry weapon. However, because the firepower of pistols must be kept low in order to reduce them to manageable weight, and because only skilled soldiers can shoot them accurately beyond 10 yards, they have never been satisfactory military weapons. In legal use, pistols are most frequently carried by police and other security personnel and serve mainly as a defensive weapon of last resort. Their compact size, low cost, and ease of operation make them a common weapon in violent crime, so that pistols are a common object of laws regulating the ownership of firearms. The two classes of pistol are revolvers and automatics. Automatics have a mechanism, actuated by the energy of recoil, that feeds cartridges from a magazine in the grip. See illustration on opposite page.
piston and cylinder In mechanical engineering, a sliding cylinder with a closed head (the piston) that moves up and down (or back and forth) in a slightly larger cylindrical chamber (the cylinder) by or against pressure of a fluid, as in an engine or pump. The cylinder of a steam engine is closed by plates at both ends, with provision for the piston rod, which is rigidly attached to the piston, to pass through one of the end cover plates. The cylinder of an internal-combustion engine is closed at one end by a plate called the head and open at the other end to permit free oscil¬ lation of the connecting rod, which joins the piston to the crankshaft.
Adoration of the Magi (detail) by Nicola Pisano, c. 1259-60; part of the marble pulpit in the Baptistery at Pisa.
AUNARI/ART RESOURCE, NEW YORK
Pissarro \po-'sar-o\, (Jacob-Abraham-) Camille (b. July 10, 1830, St. Thomas, Danish West Indies—d. Nov. 13, 1903, Paris,
France) West Indian-born French painter. The son of a prosperous Jew¬ ish merchant, he moved to Paris in 1855. His earliest canvases are broadly painted figure paintings and landscapes; these show the careful observation of nature that was to remain a characteristic of his art. In 1871 he took a house in Pontoise, in the countryside outside Paris. These surroundings formed the theme of his art for some 30 years. Pissarro’s leading motifs during the 1870s and 1880s were houses, factories, trees, haystacks, fields, labouring peasants, and river scenes. In these works, forms do not dissolve but remain firm, and colours are strong; during the latter part of the 1870s his comma-like brushstrokes frequently recorded the sparkling scintillation
of light. These works were admired by the Impressionist artists; Pissarro was the only Impressionist painter who participated in all eight of the group’s exhibitions. Despite acute eye trouble, his later years were his most prolific.
Self-portrait by Camille Pissarro, oil on canvas, 1903; in the Tate Gallery, Lon¬ don.
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pit bull terrier ► Pitt I 1505
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pit bull terrier or Staffordshire terrier Dog breed developed in 19th-century Britain for fighting other dogs in pits. It was created by crossing the bulldog (which at the time was longer-legged and more agile) with a terrier, possibly the fox terrier. Once known by such names as bull- and-terrier and half-and-half, the pit bull is a stocky, muscular, unusually strong dog with powerful jaws, standing 17-19 in. (43^48 cm) tall and weighing 30-50 lb (14-23 kg). Its stiff, short coat may be any colour, solid or variegated. See also bull terrier.
pit viper Any species of viper (subfamily Crotalinae) that has, in addi¬ tion to two movable fangs, a heat-sensitive pit organ between each eye and nostril which together help it accurately aim its strike at its warm¬ blooded prey. Pit vipers are found from deserts to rain forests, primarily in the New World. They may be terrestrial, arboreal, or aquatic. Some species lay eggs; others produce live young. See also bushmaster, copper¬ head, FER-DE-LANCE, MOCCASIN, RATTLESNAKE.
Pitcairn Island Island (pop., 2003 est.: 47) and British overseas ter¬ ritory, south-central Pacific Ocean. It is the only inhabited island of the Pitcairn island group, which also includes Henderson, Ducie, and Oeno islands. It has an area of about 2 sq mi (5 sq km). Discovered in 1767 by the British, it was uninhabited until 1790, when it was settled by muti¬ neers from HMS Bounty, led by Fletcher Christian. Pitcairn was annexed by Britain in 1838. The inhabitants were removed to Norfolk Island in 1856 because of overpopulation. Some returned to Pitcairn, and it is their descendants who make up the present population, subsisting on fishing and farming. In 1970 the British High Commissioner in New Zealand was appointed Pitcairn’s governor.
pitch In music, position of a single sound in the complete range of sound; this quality varies with the number of vibrations per second (hertz, Hz) of the sounding body and is perceived as highness or lowness. A higher pitch has a higher number of vibrations. In Western music, standard pitches have long been used to facilitate tuning. A confusing variety of pitches prevailed until the 19th century, when the continual rise in pitch made some international agreement a matter of practical necessity. In 1939 the A above middle C was standardized as 440 Hz. See also inter¬ val; TUNING AND TEMPERAMENT.
pitchblende Amorphous, dense, black, pitchy form of the crystalline uranium oxide mineral uraninite; it is one of the primary mineral ores of uranium. Pitchblende is found in granular masses and has a greasy lustre. Three chemical elements were first discovered in pitchblende: uranium, polonium, and radium. Deposits, frequently in association with uraninite or with secondary uranium minerals, are known in the Czech Republic, Britain, the Northwest Territories and Saskatchewan in Canada, and Ari¬ zona, Colorado, Montana, New Mexico, and Utah in the U.S.
Pitcher, Molly (b. c. 1753—d. Jan. 22, 1832, Carlisle, Pa., U.S.) U.S. patriot. Little is known of her early life, though she is thought to have been Irish. In the American Revolution she accompanied her husband, William Hays, a gunner, at the Battle of Monmouth (1778), where she carried pitchers of water to wounded American soldiers, earning the nickname “Molly Pitcher.” According to legend, after her husband collapsed from