Eratosthenes \ l er-9- , tas-th9-,nez\ of Cyrene (b. c. 276 bc, Cyrene, Libya—d. c. 194, Alexandria, Egypt) Greek scientific writer, astronomer, and poet. He settled in Alexandria c. 255 bc and became director of its great library. He is the first person known to have calculated the Earth’s circum¬ ference, though the exact length of the units (stadia) he used is uncertain. He also measured the tilt of Earth’s axis with great accuracy, compiled a star catalog, worked out a calendar that included leap years, and tried to fix the dates of literary and political events since the siege of Troy.
Erbakan \,er-ba-'kan\, Necmettin (b. c. 1926, Sinop, Tur.) First leader of an Islamic political party to win a general election in Turkey (1995). Son of an Ottoman-era religious court judge, he studied mechani¬ cal engineering before being elected to the National Assembly in 1969. Despite Turkey’s strong secular tradition and its laws prohibiting the for¬ mation of parties based on religious ideology, Erbakan formed an Islamic party in 1970 and another in 1972, serving twice as deputy prime min¬ ister. His third attempt to form a party created the Refah ("Welfare") Party, which won the most seats in the 1995 elections. As prime minister, he formed a coalition government in 1996, but his party was outlawed in 1997; he was then banned from politics.
Ercker, Lazarus (b. c. 1530, Annaberg, Saxony—d. c. 1594, Prague, Bohemia) German writer on early metallurgy. In 1554 Ercker was appointed assayer at Dresden, the first of his many positions in the Sax¬ ony bureaucracy, and later became a control tester of coins. His system¬ atic review of the techniques then in use for testing alloys and minerals of silver, gold, copper, antimony, mercury, bismuth, and lead, of obtain¬ ing and refining such metals, and of extracting acids, salts, and other compounds may be regarded as the first manual of analytical and metal¬ lurgical chemistry.
Erdos Ver-dosh\, Paul (b. March 26, 1913, Budapest, Hung.—d. Sept. 20, 1996, Warsaw, Pol.) Hungarian mathematician. He proved a classic theorem of number theory (1933), founded the study of probabilistic num¬ ber theory with Aurel Wintner and Mark Kac, proved important results
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630 i Erech > Erie
in approximation theory with Paul Turan, and with Atle Selberg gave an astounding elementary proof of the prime number theorem (1949). Famously eccentric, he traveled almost constantly for his last 40 years, collaborating with hundreds of mathematicians on numerous problems.
Erech Ve-,rek\ or Uruk Vti-.rukA Ancient city, Mesopotamia. Located northwest of Ur on the Euphrates River, it was one of the greatest cities of Sumer and was enclosed by brickwork walls that, according to legend, were built by the mythical hero Gilgamesh. Excavations have traced suc¬ cessive cities that date from the prehistoric Ubaid period (c. 5000 bc) to Parthian times (126 bc-ad 224), when in c. 70 bc an ancient school of learned scribes was still using cuneiform script. Urban life in what is known as the Erech-Jamdat Nasr period (c. 3500-2900 bc) is more fully illustrated at Erech than at any other Mesopotamian city.
Erechtheus \i-'rek-,thus, i-'rek-the-os\ Legendary god-king of Athens. According to Homer’s Iliad , he was born from the earth and raised by Athena, who established him in her temple at Athens. Later tradition associates him with a huge snake that was thought to live in the temple. In a lost play by Euripides, Erechtheus sacrificed his daughter Chthonia to ensure a victory in war, and as punishment was destroyed by either Posei¬ don or Zeus.
eremite See hermit
Ereshkigal \a-'resh-,ke-g3l\ In Mesopotamian religion, the goddess of the underworld. Her chief enemy was her sister Ishtar, a fertility goddess and guardian of life. Namtar, the death-bringing demon, was her offspring and servant. Her cult extended to Egypt, Arabia, and Asia Minor.
Eretria \e-'re-tre-o\ Ancient Greek town on the island of Euboea. Jointly with its neighbour Chalkis, it founded Cumae in Italy (c. 750 bc), the first of the Greek colonies in the west. Subsequent rivalry with Chalkis cul¬ minated in war, and by the Classical period Chalkis was the leading city of Euboea. In 499-498 bc Eretrian triremes sailed to support the Ionian revolt against Persia, for which act Darius I destroyed the city (490 bc) and deported the population. It was rebuilt, but under Macedonian and Roman rule it became insignificant. There are extensive ruins at the site.
Erfurt \'er-,furt\ City (pop., 2002 est.: 200,126), central Germany. Bon¬ iface founded a bishopric in Erfurt in ad 742, and by 805 it was an impor¬ tant centre on the Frankish empire’s eastern border. Erfurt was granted municipal rights c. 1250 and joined the Hanseatic League in the 15th cen¬ tury. The city passed to Prussia in 1802, forming part of Prussian Saxony until 1945. Erfurt was the site of the first meeting of the leaders of East and West Germany in 1970. It is dominated by its 12th-century cathedral; other buildings include the monastery where Martin Luther was a monk (1505-08). Erfurt is an important road and railway junction and a com¬ mercial centre.
ergativify Tendency of a language to pair the subject, or agent, of an intransitive verb with the object, or patient, of a transitive verb. This con¬ trasts with the situation in nominative-accusative languages such as Latin or English, in which the subjects of both transitive and intransitive verbs are paired grammatically and distinguished from the object of a transitive verb. Languages or language families that display ergativity to varying degrees include Sumerian, Caucasian languages, Eskimo-Aleut, Maya, Aus¬ tralian Aboriginal languages, and many American Indian languages.
ergonomics or human engineering or human factors engi¬ neering Profession of designing machines, tools, and work environ¬ ments to best accommodate human performance and behaviour. It aims to improve the practicality, efficiency, and safety of a person working with a single machine or device (e.g., using a telephone, driving a car, or oper¬ ating a computer terminal). Taking the user into consideration has prob¬ ably always been a part of tool design; for example, the scythe, one of the oldest and most efficient human implements, shows a remarkable degree of ergonomic engineering. Examples of common devices that are poorly designed ergonomically include the snow shovel and the computer or typewriter keyboard.
ergot Ver-got, 'er-,gat\ Disease of cereal GRASses, especially rye, caused by the fungus Claviceps purpurea. An ear of rye infected with ergot exudes a sweet, yellowish mucus. Ergot is the source of drugs used to control post¬ partum hemorrhage and to treat migraine headaches. Lysergic acid, from which the powerful hallucinogen LSD is synthesized, comes from ergot. Taking an overdose of ergot-derived medications or eating flour milled from ergot-infected rye can cause ergotism (also called St. Anthony’s Fire)
in humans and livestock; symptoms may include convulsions, miscarriages in females, and dry gangrene, and may result in death.
Ergun River See Argun River