Ogilvy Yo-gsl-veV David M(ackenzie) (b. June 23, 1911, West Horsley, Surrey, Eng.—d. July 21, 1999, near Bonnes, France) British advertising executive. After an Oxford education, he worked as an appren¬ tice chef and stove salesman before taking a job in an advertising agency. He spent a year in the U.S. learning American advertising techniques. In 1948, with Anderson Hewitt, he formed Hewitt, Ogilvy, Benson & Mather, which became one of the world’s largest advertising firms. He is noted for reminding his colleagues that “the consumer is not a moron,” and his ads for brands such as Schweppes and Rolls-Royce were admired for their creativity.
Oglethorpe, James (Edward) (b. Dec. 22, 1696, London, Eng.—d. June 30/July 1, 1785, Cranham Hall, Essex, Eng.) English army officer. After serving in the British army from 1712 to 1722, he entered Parlia¬ ment, where he became interested in prison reform. In 1732 he secured a charter for a colony in what became Georgia, where debtors could start a new life and persecuted Protestants could practice freely. He accompa¬ nied the first settlers to found Savannah (1733) and led the defense of the territory against attacks by Spain (1739, 1742). He returned to England in 1743.
Ogodei Vo-go-.daV (b. 1185, Mongolia—d. 1241, Karakorum) Son of Genghis Khan who succeeded his father in 1229 and greatly expanded the Mongol empire. He established his headquarters in central Mongolia and built the capital city of Karakorum. Like his father, he carried out simultaneous campaigns by relying on generals who acted independently but were subject to his orders. Allying himself with China’s Southern Song dynasty, Ogodei attacked the Juchen dynasty in northern China, tak¬ ing its capital in 1234. Meanwhile, his nephew Batu defeated Russia while other generals were attacking Iran and Iraq. Only Ogodei’s death (during a drinking bout) prevented the Mongols from invading western Europe. See also Golden Horde; Kublai Khan; Mongke.
Ogooue River or Ogowe \,o-g6-'wa\ River River, west-central Africa, mainly in Gabon. It rises in the Republic of the Congo and flows northwest, then west, emptying into the Atlantic Ocean south of Port- Gentil after a course of 750 mi (1,200 km). It is navigable for less than one-third of its length but is heavily used for shipping goods, including lumber, to the coast.
ogum writing see ogham writing
O'Hara, John (Henry) (b. Jan. 31, 1905, Pottsville, Pa., U.S.—d. April 11, 1970, Princeton, N.J.) U.S. novelist and short-story writer. O’Hara developed the objective, straightforward style he used in his fic¬ tion while working as a critic and reporter in New York City. His works stand as a social history of upwardly mobile Americans of the 1920s through the 1940s. Among them are the popular novels Appointment in Samarra (1934); Butterfield 8 (1935; film, 1960); Pal Joey (1940), adapted as a musical; Ten North Frederick (1955; film, 1958); and From the Terrace (1958; film, 1960).
O'Higgins, Bernardo (b. probably Aug. 20, 1776/78, Chilian, Chile, Viceroyalty of La Plata—d. October 1842, Peru) South American revolu¬ tionary leader and first Chilean head of state (1817-23). The illegitimate son of a Spanish officer of Irish origin, he was educated in Peru, Spain, and England, where his Chilean nationalism was awakened. When Napoleon invaded Spain (1808) and Spanish control of Chile relaxed, he became a member of Chile’s new congress. He led the defensive forces when Chile was invaded by royalists from Peru in 1814; defeated, he fled to Argentina. He returned in 1817 with Jose de San Martin and defeated the Spanish. Elected supreme director of Chile, he established a working governmental organization, but his reforms antagonized conservatives and he resigned.
Ohio State (pop., 2000: 11,353,140), U.S., north-central region. Bor¬ dered by Michigan, Pennsylvania, West Virginia, Kentucky, and Indiana, it covers 44,828 sq mi (116,104 sq km). Its capital is Columbus. Lake Erie is on its northern boundary; the Ohio River forms part of its southeastern and southern boundary. Ohio was originally inhabited by prehistoric
Hopewell mound builders, who disappeared c. ad 400. The earliest Euro¬ pean explorers found the area occupied by Miami, Shawnee, and other Indian peoples. The region was ceded to Britain by France after the French and Indian War. In 1803 it became the 17th state and the first state carved out of the Northwest Territory (see Northwest Ordinances). During the 19th century, it became one of the first great industrial states because of its location, transport facilities, and natural resources, including coal, petroleum, and natural gas. Although manufacturing is its most important economic activity, nearly two-thirds of the state is still farmland. It was the birthplace or residence of eight U.S. presidents— William H. Harrison, Ulysses S. Grant, Rutherford B. Hayes, James Garfield, Benjamin Harrison, William McKinley, William H. Taft, and Warren G. Harding. Its major cit¬ ies include Columbus, Cleveland, Cincinnati, Toledo, Akron, and Dayton.
Ohio Co. Organization of Englishmen and Virginia colonists, estab¬ lished in 1748 to promote trade with American Indians and secure Brit¬ ish control of the Ohio River valley for settlement. Activity in the area claimed by France led to the last French and Indian War (1754). A sepa¬ rate organization, the Ohio Co. of Associates (1786), founded Marietta, Ohio, the first permanent settlement north of the Ohio River.
Ohio Idea Proposal to redeem American Civil War bonds in paper money instead of gold. The plan, part of the debate between hard-money advo¬ cates and soft-money or Greenback movement supporters after the Civil War, was sponsored by George Pendleton and was especially popular in the Midwest. Endorsed by the Democratic Party in 1868, it died with the election of Ulysses S. Grant and passage of the Public Credit Act (1869), which provided for payment of government obligations in gold.
Ohio River Major river, eastern central U.S. Formed by the confluence of the Allegheny and Monongahela rivers, it flows northwest out of Penn¬ sylvania, and west and southwest to form the state boundaries of Ohio- West Virginia, Ohio-Kentucky, Indiana-Kentucky, and Illinois-Kentucky. After a course of 975 mi (1,569 km), it empties into the Mississippi River at Cairo, Ill. It is navigable and has supported commerce since the earliest settlements. The river’s strategic importance was recognized by the 1750s. After the French and Indian War, the English controlled the territory around the river.
Ohio State University U.S. state university system consisting of a main campus in Columbus and branches in five other locations. It was established in 1870 as a land-grant institution. The main campus is a comprehensive research institution, with colleges of agriculture, dentistry, law, medicine, and veterinary medicine. Research facilities include a transportation research centre, a freshwater laboratory, a supercomputer centre, and a polar research centre.
Ohm, Georg Simon (b. March 16 6, 1854, Munich) German physicist.
While teaching mathematics at the Jesuits’ College in Cologne (1817—
27), he discovered that the flow of electric current through a conductor is directly proportional to the poten¬ tial difference, or voltage, and inversely proportional to the resis¬ tance. He resigned when his theory (Ohm's law) was coldly received. His theory soon came to be widely rec¬ ognized, and he subsequently taught in Niirnberg (1833—49) and Munich (1849-54). The physical unit mea¬ suring electrical resistance was named for him.
Ohm's law Relationship between the potential difference (voltage), electric current, and resistance in an electric circuit. In 1827 Georg Simon Ohm discovered that at constant temperature, the current I in a circuit is directly proportional to the potential difference V, and inversely propor¬ tional to the resistance R, or I = V/R. Resistance is generally measured in ohms (£2). Ohm’s law may also be expressed in terms of the electromo¬ tive force E of an electric energy source, such as a battery, or E = IR. In an alternating-current circuit, when the combination of resistance and reactance, called impedance Z, is constant. Ohm’s law is applicable and V/I = Z.