Mercator Vmsr-'ka-toA, Gerardus orig. Gerard Kremer (b.
March 5, 1512, Rupelmonde, Flanders—d. Dec. 2, 1594, Duisburg, Duchy of Cleve) Flemish cartographer. He received a master’s degree in 1532 from the University of Louvain (Belgium), where he settled. By 24 he was a skilled engraver, calligrapher, and scientific-instrument maker. He and his colleagues made Louvain a centre for construction of maps, globes (terrestrial and celestial), and astronomical instruments. He was appointed court cosmographer to Duke Wilhelm of Cleve in 1564, and in 1569 he perfected what has become known as the Mercator projection, in which parallels and meridians are rendered as straight lines spaced so as to produce at any point an accurate ratio of latitude to longitude. It permitted mariners to steer a course over long distances, plotting straight lines without continually adjusting compass readings. While the merid¬ ians are equally spaced parallel vertical lines, the lines of latitude are spaced farther and farther apart as their distance from the Equator increases; on world maps the projection greatly enlarges areas distant from the Equator.
mercenary Vmor-s^-.er-eV Hired professional soldier who fights for any state or nation without regard to political principles. From the earli¬ est days of organized warfare, governments supplemented their military forces with mercenaries. After the Hundred Years’ War (1337-1453), Swiss soldiers were hired out all over Europe by their own cantonal gov¬ ernments and won a high reputation. Rulers of the German state of Hesse also hired out their soldiers, and Hessian troops fought for the British in the American Revolution. Since the late 18th century, most mercenaries have been individual soldiers of fortune.
Mercer, Johnny orig. John Herndon Mercer (b. Nov. 18, 1909, Savannah, Ga., U.S.—d. June 25, 1976, Bel Air, Calif.) U.S. songwriter. After moving to New York City in the late 1920s, Mercer began to write lyrics while supporting himself as an actor. He later joined Paul White- man’s orchestra as singer and master of ceremonies. In 1939 he joined Benny Goodman’s Camel Caravan radio show. In 1942 Mercer cofounded Capitol Records. On Broadway, he collaborated with Harold Arlen on St. Louis Woman (1946) and Saratoga (1959) and also provided lyrics for Seven Brides for Seven Brothers (1954), Li’l Abner (1956), and Foxy (1964). His songs for films won four Academy Awards. He collaborated with composers such as Hoagy Carmichael, Henry Mancini, Jerome Kern, and Jimmy Van Heusen and is credited with more than 1,000 lyrics, includ¬ ing those for “Ac-cent-tchu-ate the Positive,” “One for My Baby,” “Autumn Leaves,” and “Moon River.”
mercerization X.mor-ss-ro-'za-shonX Chemical treatment applied to cotton fibres or fabrics to make them permanently able to accept dyes and various chemical finishes more easily. The method, patented in 1850 by the English calico printer John Mercer, also gives cotton cloth
increased tensile strength and greater absorptive properties. Higher-quality cotton goods are usually mercerized. The treatment consists of dipping the yam or fibre in a solution of sodium hydroxide and then treating the material with water or acid to neutralize the sodium hydroxide.
merchandising Element of marketing concerned especially with the sale of goods and services to customers. One aspect of merchandising is advertising, which aims to capture the interest of the segment of the popu¬ lation most likely to buy the product. Merchandising also involves prod¬ uct display; companies provide retailers with display and promotional materials and negotiate shelf space for their products. The development of sales strategies includes the determination of pricing, discounts, and special offers; the invention of sales pitches; and the identification of avenues for sales, including store-based retailing and alternative means such as direct-mail marketing, telemarketing, commercial Web sites, vend¬ ing machines, and door-to-door sales.
Merchant, Ismail See James Ivory
merchant marine Commercial ships of a nation, whether privately or publicly owned, and the personnel who operate such ships, as distinct from the personnel of naval vessels. Merchant ships are used to transport people, raw materials, and manufactured goods. Merchant fleets can be important economic assets for nations with limited natural resources or a small industrial base. By carrying the commerce of other nations on the seas, a merchant fleet contributes to its home nation’s foreign-exchange earnings, promotes trade, and provides employment. The U.S. Merchant Marine Academy (founded 1943) is in Kings Point, N.Y.
Mercia Vmsr-shoN Ancient kingdom, central England. One of the Anglo- Saxon kingdoms of the Heptarchy, it comprised the border areas, corre¬ sponding to modern Staffordshire, Derbyshire, Nottinghamshire, and northern West Midlands and Warwickshire. Offa, who ruled from 757 to 796, created a single state from the River Humber to the English Chan¬ nel. After Offa’s death, Mercia declined, overshadowed by Wessex. In 877 the Danes divided Mercia into English and Danish sections. After the reconquest of the Danish lands in the early 10th century, it came under the rule of Wessex.
Mercury In Roman religion, the god of merchants, commonly identified with the Greek messenger of the gods, Hermes. His temple on Rome’s Aventine Hill was dedicated in 495 bc. The goddess Maia was identified as his mother, and the two were honoured in a festival on May 15. Mer¬ cury is sometimes depicted holding a purse, symbolic of his business functions. More often he is given the attributes of Hermes and portrayed wearing winged sandals or a winged cap and carrying a caduceus.
mercury or quicksilver Metallic chemical element, chemical symbol Hg, atomic number 80. Mercury is the only elemental metal that is liquid at ordinary temperatures, with a freezing point of -38 °F (-39 °C) and a boiling point of 674 °F (356.9 °C). Silvery white, dense, toxic (see mer¬ cury poisoning), and a good conductor of electricity, mercury is occasion¬ ally found free in nature but usually occurs as the red sulfide ore, cinnabar (HgS). It has many uses—in dental and industrial amalgams, as a catalyst, in electrical and measuring apparatus and instruments (e.g., thermom¬ eters), as the cathode in electrolytic cells, in mercury-vapour lamps, and as a coolant and neutron absorber in nuclear power plants. Many of mer¬ cury’s compounds, in which it has valence 1 or 2, are pigments, pesti¬ cides, and medicinals. It is a dangerous pollutant because it concentrates in animal tissues in increasing amounts up the food chain.
Mercury Innermost planet of the solar system. Its average distance from the Sun is about 36 million mi (58 million km), but its highly elliptical orbit carries it 7.5 million mi (12 million km) nearer to and farther from the Sun. It is the second-smallest major planet (after Pluto), having a diameter of about 3,030 mi (4,880 km) and a mass about one-eighteenth of Earth’s. With the shortest period of revolution (only 88 Earth days) and the highest average orbital speed (30 mi/second, or 48 km/second) of any planet, it is aptly named after the fleet-footed Roman messenger god. It spins very slowly, making one complete rotation relative to the stars every 59 Earth days, while its solar day (from one sunrise to the next) is 176 Earth days, owing to its revolution around the Sun. Its surface is heavily cratered. Its most impressive feature is perhaps the 800-mi (1,300- km) Caloris Basin, formed by a huge meteorite impact. Mercury also has steep cliffs that extend for hundreds of miles. The discovery of a mag¬ netic field in its vicinity suggests it has a large iron core, which would account for a mean density almost as high as Earth’s. Its atmosphere is