heir One who inherits or is entitled to succeed to the possession of prop¬ erty after the death of its owner. In most jurisdictions, statutes of descent determine transfer of title to property if no will names the recipient. One may be either heir apparent or heir presumptive during the lifetime of the property holder. An heir apparent’s right to an inheritance cannot be voided or undone except by exclusion under a valid will. An heir pre¬ sumptive’s right to inherit may be defeated by the birth of a nearer rela¬ tive. In Britain, the heir apparent of the monarch is the eldest son. If there are no sons, the eldest daughter is heiress presumptive. See also primo¬ geniture.
Heisei emperor See Akihito
Heisei Vha-'sa\ period Japanese reign period that began in 1989 when Akihito became emperor on the death of his father, Hirohito. The Heisei period has been a sober one for the Japanese, marked by turbulent poli¬ tics (with 11 prime ministers in its first dozen years), an economic slow¬ down, and crises in the financial world. A devastating earthquake in Kobe and a nerve-gas attack on a Tokyo subway line by members of AUM Shin- rikyo (both in 1995) contributed to the generally dark picture of the period. Positive events have included the wedding of the crown prince and host¬ ing the 1998 Winter Olympic Games in Nagano. See also Showa period.
Heisenberg Vhl-zffi-borgX, Werner (Karl) (b. Dec. 5, 1901, Wurzburg, Ger.—d. Feb. 1, 1976, Munich, W.Ger.) German physicist. Educated at Munich and Gottingen, he taught at the University of Leipzig (1927—41) and directed the Max Planck Institute for Physics (1942-76). In 1925 he solved the problem of how to account for the stationary dis¬ crete energy states of an anharmonic oscillator, a solution that launched the development of quantum mechanics. In 1927 he published his famous uncertainty principle. He also made important contributions to the theories of the hydrodynamics of turbulence, the atomic nucleus, ferromagnetism, cosmic rays, and subatomic particles. He was awarded the Nobel Prize for Physics in 1932 for his work on quantum mechanics. He led Germa¬ ny’s efforts in World War II (1939-45) to develop an atomic bomb.
Heisenberg uncertainty principle See uncertainty principle
Heisman, John (William) (b. Oct. 23, 1869, Cleveland, Ohio, U.S.—d. Oct. 3, 1936, New York City, N.Y.) U.S. collegiate gridiron
football coach and one of the game’s greatest innovators. Heisman played football for both Brown University and the University of Pennsylvania. He was responsible for legalizing the forward pass in 1906, and he origi¬ nated the centre snap and the “hike” count signals of the quarterback in starting play. He coached at several colleges between 1892 and 1927, compiling a record of 185 wins, 68 losses, and 18 ties. The Heisman Tro¬ phy was named for him.
Heisman Trophy Annual award given to the outstanding college grid¬ iron football player in the U.S. The trophy was instituted in 1935 by New York City’s Downtown Athletic Club and was officially named the fol¬ lowing year for the club’s first athletic director, the player-coach John Heisman. The winner is determined by a poll of sports writers.
Hejaz \he-'jaz\ Arabic Al-Hijaz \,al-he-'jaz\ Region of western Saudi Arabia. It occupies an area of 134,600 sq mi (348,600 sq km) along the Red Sea coast of the Arabian Peninsula, from Jordan to c AsIr province. Its northern portion was inhabited by the 6th century bc. In the 7th century ad two of its cities, Mecca and Medina, were the birthplace of Islam; they remain Islam’s holiest cities. In 1258 the region fell to the Mamluk dynasty and in 1517 to the Ottomans. In 1916 Sharif Husayn ibn c AlI revolted and proclaimed himself king of the Hejaz. Ibn Sa c 0d, the ruler of Nejd, assumed the title in 1926, and in 1932 he united Hejaz, Nejd, and other districts to form the Kingdom of Saudi Arabia.
Hejira See Hijrah
Hel In Norse mythology, the realm of the dead and, later, the goddess of the dead. She was the daughter of Loki. Her kingdom, Niflheim, or the World of Darkness, was divided into several sections. Murderers, perjur¬ ers, and adulterers suffered torment in a castle filled with serpents’ venom, while the dragon Nidhogg sucked their blood. Those who fell in battle went to Valhalla and thus avoided Hel.
Helen In Greek mythology, the most beautiful woman in Greece, who was the indirect cause of the Trojan War. She was a daughter of Zeus, either by Leda or by Nemesis. Her brothers were the Dioscuri, and her sis¬ ter was Clytemnestra, wife of Agamemnon. Helen was the wife of Mene- laus. When Paris, son of Priam, was asked to decide which goddess was the most beautiful, he chose Aphrodite, who rewarded him with the most beautiful woman in the world. Seducing Helen with the goddess’s help, Paris carried her off to Troy, and the Greeks sent a military force to pur¬ sue them. At the war’s end, with Paris dead, Helen returned to Sparta with Menelaus.
Helena Vhe-l9-no\ City (pop., 2000: 25,780), capital of Montana, U.S. Located near the Missouri River in west-central Montana, in an area vis¬ ited by the Lewis and Clark Expedition (1805), it was settled after gold was discovered there in 1864 (in Last Chance Gulch, now the city’s main street). It became capital of the territory in 1875 and of the state in 1889. In addition to state government activities, Helena is an agricultural and livestock trade centre and has light manufactures. The capitol building has a copper-covered dome surmounted by a reproduction of the Statue of Liberty.
Helena, Saint (b. c. 248, Drepanon?, Bithynia, Asia Minor—d. c. 328, Nicomedia; Western feast day Aug. 18; Eastern feast day [with Constan¬ tine] May 21) Roman empress and mother of Constantine I. She was the wife of Constantius I (Constantius Chlorus) before he became caesar (sub¬ emperor), and she bore Constantine before she was renounced for politi¬ cal reasons. She became a Christian under her son’s influence. Implicated in the execution of her daughter-in-law (326), she made a pilgrimage to the Holy Land and had churches built in Jerusalem and Bethlehem on the sites of the Ascension and the Nativity. By the late 4th century she was reputed to have found Christ’s cross.
Helga, Saint See Saint Olga helicon See sousaphone
Helicon, Mount Mountain, east-central Greece, part of the Helicon range, a continuation of the higher Parnassus range. Located near the Gulf of Corinth, it is 5,738 ft (1,749 m) high. It was celebrated by the ancient Greeks as the home of the Muses; on it were the fountains of Aganippe and Hippocrene, the supposed sources of poetic inspiration.
helicopter Aircraft with one or more power-driven horizontal rotors that enable it to take off and land vertically, move in any direction, or remain stationary in the air. Since a rotor is essentially a rotating airfoil,
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858 I helioflagellate ► Heller
a helicopter is often described as a rotary-wing aircraft, in contrast to a conventional fixed-wing airplane. One of the earliest ideas for flying, it appeared in China and Renaissance Europe as a toy and in Leonardo da Vinci’s designs. The Frenchman Paul Cornu made the first manned flight in 1907. Igor Sikorsky produced the first successful prototype in 1939, which was followed by rapid development in the U.S. and Europe. It is widely used for civilian transport, rescue work, and various commercial purposes. It has been used by military forces since the Korean War (1950- 53) for transporting material, moving assault troops, and directly attack¬ ing other forces.
helioflagellate V.he-le-o-'fla-js-taA Any of a class of freshwater pro¬ tozoans. They are sometimes considered relatives of heliozoans (organ¬ isms that for movement have extensions of cytoplasm called pseudopodia, but no flagella) because of their slender, radiating pseudopodia. The cores of the pseudopodia of some helioflagellates radiate from a central gran¬ ule, as they do in some heliozoans. Helioflagellate life cycles alternate between flagellate and heliozoan phases. Some members are spherical, others oval.