Mount Vernon Home and burial place of George Washington. It is located in northern Virginia, U.S., on the Potomac River near Washington, D.C. The estate was inherited by Washington in 1752. Near the 18th- century Georgian mansion is a plain brick tomb, built at Washington’s direction, that holds his remains and those of his wife and several family members. After the U.S. government declined to buy it, in 1858 the Mount Vernon Ladies’ Association of the Union raised $200,000 and purchased the house and 200 acres (80 hectares) of the estate; the association still maintains the site.
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Mount Wilson Observatory ► mouth-to-mouth resuscitation I 1303
Mount Wilson Observatory Astronomical observatory located atop Mount Wilson, near Pasadena, California, U.S. Founded in 1904 by George Ellery Hale (1868-1938), it was operated jointly with Palomar Observatory as Hale Observatories (1948-80). Its largest optical telescope, with a diam¬ eter of 100 in. (2.5 m), enabled Edwin Hubble and his associates to discover evidence of an expanding universe and to estimate its size.
mountain Landform that rises well above its surroundings, generally exhibiting steep slopes, a relatively confined summit area, and consider¬ able local relief (inequalities of elevation). Mountains are considered larger than hills, but the term has no standardized geologic meaning. Mountains are formed by the folding, faulting, or upwarping of the Earth’s surface due to the movement of plates (see plate tectonics) or by the emplacement of volcanic rock onto the surface. For example, the Hima¬ layan Mountains where India meets the Eurasian Plate were formed by a collision between plates that caused extreme compressional folding and the uplifting of large areas. The mountain ranges around the Pacific basin are attributed to the sinking of one plate beneath another. See also plateau.
mountain ash Any of several shrubs or trees of the genus Sorbus, in the ROSE family, native to the Northern Hemisphere. They are widely cul¬ tivated as ornamentals for their white flower clusters and bright-orange fruits. Most noteworthy are the handsome American mountain ash, or dogberry ( S. americana), and European mountain ash ( S. aucuparia), also called rowan, or quickbeam. The European species grows to 60 ft (18 m), twice as high as the American species.
mountain goat or Rocky Mountain goat Ruminant (bovid species Oreamnos americanus ) of the Yukon to the northern Rockies that is more closely related to antelopes than to goats. Stocky, with a hump at the withers, mountain goats stand about 40 in. (1 m) at the shoulder. Both sexes bear short, hollow, slightly backward-curving, black horns. The shaggy, coarse white hair covers a thick, woolly underfur, and a beard frames the slender muzzle. The hooves are black. Mountain goats are agile climbers and can leap more than 12 ft (3.5 m). They live in small bands above the timberline, eating moss, lichen, and scrub foliage.
mountain laurel Flowering evergreen shrub ( Kalmia latifolia ) of the heath family, occurring in most mountainous regions of eastern North America. It grows to about 3-18 ft (1-6 m) in height and has oval leaves. The rosy, pink, or white flowers appeal' in large clusters above the foli¬ age. The shrub is popular in landscape plantings.
mountain lion See cougar mountain sheep See bighorn
mountaineering or mountain climbing Sport of attaining, or attempting to attain, high points in mountainous regions, mainly for the joy of the climb. The pleasures of mountaineering lie not only in the con¬ quest of the peak but also in the physical and spiritual satisfactions brought about through intense personal effort, ever-increasing proficiency, and contact with natural grandeur. The greater rewards do not come with¬ out considerable risk and danger. The first great peak ascended in mod¬ em times was Mont Blanc, in 1786. Other Alpine peaks followed, capped by the ascent of the Matterhorn in 1865. By the 1910s, most peaks of the Andes, the Rockies, and other Western Hemisphere ranges had been climbed, including Mount McKinley (1913). Beginning in the 1930s a series of successful ascents of mountains in the Himalayas occurred; the summits of many of the Himalayan mountains were not reached until the 1950s, however. Of these climbs, the best known is the 1953 ascent of Mount Everest by Edmund Hillary and Tenzing Norgay. In the 1960s moun¬ taineering became an increasingly technical sport, emphasizing the use of specialized anchoring, tethering, and grappling gear in the ascent of ver¬ tical rock or ice faces.
Mountbatten (of Burma), Louis Mountbatten, 1 st Earl orig. Louis Francis Albert Victor Nicholas, prince of Battenberg
(b. June 25, 1900, Frogmore House, Windsor, Eng.—d. Aug. 27, 1979, Donegal Bay, off Mullaghmore, County Sligo, Ire.) British statesman and
naval commander. Son of Prince Louis of Battenberg and great-grandson of Queen Victoria, he entered the Royal Navy in 1913 and became an aide to the prince of Wales in 1921. In World War II he was allied commander for Southeast Asia (1943^-6) and directed the recapture of Burma. Appointed viceroy of India (1947), he administered the transfer of power from Britain to the independent nations of India and Pakistan and served as the first governor-general of India (1947—48). He became first sea lord (1955-59) and chief of the United Kingdom Defense Staff (1959-65). In 1979, while on a sailing visit to Ireland, he was assassinated by Irish ter¬ rorists who planted a bomb on his boat.
Mountbatten family See Battenberg family Mounties See Royal Canadian Mounted Police
mourning dove Species ( Zenaida macroura) of pigeon (family Columbidae), the common wild pigeon of North America. They have long, pointed tails, and the sides of the neck are violet and pink. Their name comes from their call’s haunt¬ ing, mournful tone. Mourning doves are migratory; the northernmost populations migrate the farthest south. They are popular game birds.
See also dove.
mouse Any of many species (fam¬ ily Muridae) of small, scampering rodents. They are distinguished from RATS principally by their smaller size.
Mice are basically Asian in origin, but species have been introduced worldwide. Species in other rodent families (e.g., deer mouse, pocket mouse) are called mice without sci¬ entific basis. Mice eat grains, roots, fruit, grass, and insects. They can become pests but are mostly benefi¬ cial; they are the main prey of most furbearers and of predators that might otherwise take more valuable prey. The white laboratory mouse is a form of house mouse. See also field mouse.
mouse Hand-controlled electromechanical device for interacting with a digital computer that has a graphical user interface. The mouse can be moved around on a flat surface to control the movement of a cursor on the com¬ puter display screen. Equipped with one or more buttons, it can be used to select text, activate programs, or move items around the screen by quickly pressing and releasing one of the buttons (“clicking”) or by keep¬ ing a button depressed while moving the device (“clicking and dragging”).
mouse deer See chevrotain
Mouskos, Mikhai Khristodolou See Makarios III
Mousterian \mu-'stir-e-3n\ industry Tool culture traditionally asso¬ ciated with the Neanderthals in Europe, western Asia, and northern Africa during the early fourth (Wiirm) glacial period (c. 40,000 bc). The Mous¬ terian tool assemblage included small hand axes made from disk-shaped cores; flake tools such as scrapers and points; toothed, sawlike instruments produced by making notches on a flake; and round limestone balls, believed to have served as bolas. Wooden spears were used to hunt large game such as the mammoth and woolly rhinoceros. Mousterian implements disappeared abruptly from Europe with the passing of the Neanderthals.
mouth or oral cavity or buccal cavity Vbok-olX Orifice through which food and air enter the body. It opens to the outside at the lips and empties into the throat at the rear and is bounded by the lips, cheeks, hard and soft palates, and glottis. Its chief structures are the teeth (see tooth), tongue, and palate. It is the site of chewing and speech formation. The mouth is lined by mucous membranes containing small glands that, along with the salivary glands, keep it moist and clear of food and other debris.