mountainous region divided between the states of Minas Gerais and Espirito Santo, eastern Brazil, occupying an area of about 3,900 square miles (10,100 square km). The mountains form a crystalline-hill upland with an average elevation of 3,000 feet (900 m). ...
town, northeastern Algeria. It is situated on a plateau at the eastern edge of the Setif plains. The plateau, once occupied by a large lake, now has several shallow depressions containing saline lakes. Sheltered on the east by wooded hills, ...
river, eastern France, flowing 124 miles (200 km) southward from the Jura Plateau through Jura and Ain departements. The river emerges from its gorge near Pont-d'Ain, having powered several hydroelectric stations (the largest of which is the Barrage de Vouglans). ...
town, western Algeria. It is situated in the Saharan Atlas, 28 miles (45 km) east of the Moroccan border. The town lies in a broad valley between Mount Aissa and Mount Mekter, on either side of the usually dry Wadi ...
town, northwestern Algeria, on the right bank of the Wadi Sennene. The town is bounded on the south by the Wadi Temouchent, with the Tessala Mountains in the background. Built on the site of the ruined Roman Albula and the ...
indigenous people of Hokkaido, Sakhalin, and the Kuril Islands who are differentiated physically and culturally from their Asian neighbours. Their origins are obscure. One claim that they were descended from European peoples has since been disproved, and many contemporary Ainu ...
mixture of gases comprising the Earth's atmosphere. The mixture contains a group of gases of nearly constant concentrations and a group with concentrations that are variable in both space and time. The atmospheric gases of steady concentration (and their proportions ...
either of two kinds of braking systems. The first, used by railroad trains, trucks, and buses, operates by a piston driven by compressed air from reservoirs connected to brake cylinders. When air pressure in the brake pipe is reduced, air ...
airline established by the Canadian Parliament in the Trans-Canada Air Lines Act of April 10, 1937. Known for almost 28 years as Trans-Canada Air Lines, it assumed its current name on January 1, 1965. Air Canada's headquarters are in Montreal.
(French: "court air"), genre of French solo or part-song predominant from the late 16th century through the 17th century. It originated in arrangements, for voice and lute, of popular chansons (secular part-songs) written in a light chordal style. Such arrangements ...
blockage of an artery or vein by an air bubble. Air can be introduced into the blood vessels during surgery or traumatic accidents. One type of traumatic embolization occurs when lung tissue is ruptured; bubbles of air pass from the ...
that military organization of a nation which is primarily responsible for the conduct of air warfare. The air force has the missions of gaining control of the air, supporting surface forces (as by bombing and strafing), and accomplishing strategic-bombing objectives. ...
French international airline originally formed in 1933 and today serving all parts of the globe. With British Airways, it was the first to fly the supersonic Concorde. Headquarters are in Paris.
the body of law directly or indirectly concerned with civil aviation. Aviation in this context extends to both heavier-than-air and lighter-than-air aircraft. Air-cushion vehicles are not regarded as aircraft by the International Civil Aviation Organization (ICAO), but the practice of ...
device that permits passage between regions of differing air pressures, most often used for passage between atmospheric pressure and chambers in which the air is compressed, such as pneumatic caissons and underwater tunnels. The air lock also has been used ...
in meteorology, large body of air having nearly uniform conditions of temperature and humidity at any given level of altitude. Such a mass has distinct boundaries and may extend hundreds or thousands of kilometres horizontally and sometimes as high as ...
group of granitic mountains rising sharply from the Sahara in central Niger. Several of these mountains approach and exceed 6,000 feet (1,800 m), the highest being Mount Greboun (6,378 feet [1,944 m]). The mountains are dissected by deep valleys, called ...
sport of racing airplanes either over a predetermined course or cross-country up to transcontinental limits. Air racing dates back to 1909, when the first international meet was held at Reims, Fr. Such meets played a large part in the development ...
any of the air-filled extensions of the breathing apparatus of many animals. Air sacs are found as tiny sacs off the larger breathing tubes (tracheae) of insects, as extensions of the lungs in birds, and as end organs in the ...
in international law, the space above a particular national territory, treated as belonging to the government controlling the territory. It does not include outer space, which, under the Outer Space Treaty of 1967, is declared to be free and not ...
load-carrying component of an air suspension system used on machines, automobiles, and buses. A system used on buses consists of an air compressor, an air-supply tank, leveling valves, check valves, bellows, and connecting piping. Basically, an air-spring bellows is a ...
the tactics of military operations conducted by airplanes, helicopters, or other manned craft that are propelled aloft. Air warfare may be conducted against other aircraft, against targets on the ground, and against targets on the water or beneath it. Air ...
military operations conducted by airplanes, helicopters, or other manned craft that are propelled aloft. Air warfare may be conducted against other aircraft, against targets on the ground, and against targets on the water or beneath it. Air warfare is almost ...
any of the machines characterized by movement in which a significant portion of the weight is supported by forces arising from air pressures developed around the craft, as a result of which they hover in close proximity to the Earth's ...
airline founded in 1932 (as Tata Airlines) and now an international airline owned by the Indian government and serving southern and east Asia, the Middle East, Europe, Africa, Australia, and New York. Headquarters are in Bombay.
boundary between the atmosphere and the ocean waters. The interface is one of the most physically and chemically active of the Earth's environments. Its neighbourhood supports most marine life.
European aircraft-manufacturing consortium formed in 1970 to fill a market niche for short- to medium-range, high-capacity jetliners and to compete with long-established American manufacturers. Full members include the German-French-Spanish-owned European Aeronautic Defence and Space Company (EADS), with an 80 percent ...
naval vessel from which airplanes may take off and on which they may land. As early as November 1910, an American civilian pilot, Eugene Ely, flew a plane off a specially built platform on the deck of the U.S. cruiser ...
river rising at Malham Tarn (lake), in North Yorkshire administrative county, historic county of Yorkshire, England. It drains the central Pennines and flows southeastward through West Yorkshire metropolitan county and across the southern part of North Yorkshire to meet the ...
the largest of the terriers, probably descended from the otterhound and an extinct broken-haired dog, the black-and-tan Old English terrier. The Airedale stands about 23 inches (58 cm) and usually weighs from 40 to 50 pounds (18 to 23 kg). ...
shaped surface, such as an airplane wing, tail, or propeller blade, that produces lift and drag when moved through the air. An airfoil produces a lifting force that acts at right angles to the airstream and a dragging force that ...
basic structure of an airplane or spacecraft excluding its power plant and instrumentation; its principal components thus include the wings, fuselage, tail assembly, and landing gear. The airframe is designed to withstand all aerodynamic forces as well as the stresses ...
faint luminescence of the Earth's upper atmosphere that is caused by air molecules' and atoms' selective absorption of solar ultraviolet and X-radiation. Most of the airglow emanates from the region about 70 to 300 km (42 to 180 miles) above ...
letters and parcels transported by airplanes. Airmail service was initiated in 1911 in England between Hendon (northwest of London) and Windsor, to celebrate the coronation of George V. Service was irregular, however, and only 21 trips were made. Continuous regular ...
any of a class of fixed-wing aircraft that is heavier than air, propelled by a screw propeller or a high-velocity jet, and supported by the dynamic reaction of the air against its wings.
site and installation for the takeoff and landing of aircraft. An airport usually has paved runways and maintenance facilities and serves as a terminal for passengers and cargo.
site and installation for the takeoff and landing of aircraft. An airport usually has paved runways and maintenance facilities and serves as a terminal for passengers and cargo.
instrument that measures the speed of an aircraft relative to the surrounding air, using the differential between the pressure of still air (static pressure) and that of moving air compressed by the craft's forward motion (ram pressure); as speed increases, ...
region, southern Chile, bounded on the east by Argentina and on the west by the Pacific Ocean. Aisen includes the Chonos Archipelago, the Taitao Peninsula, and the mainland between the Palena River in the north and O'Higgins Lake in the ...
portion of a church or basilica that parallels or encircles the major sections of the structure, such as the nave, choir, or apse (aisles around the apse are usually called ambulatories). The aisle is often set off by columns or ...
in Irish literature, a poetic or dramatic description or representation of a vision. The Vision of Adamnan is one of the best-known examples. In the 18th century the aisling became popular as a means of expressing support for the exiled ...
