Atbara \'at-ba-ra\ River River, North Africa. Rising in the Ethiopian highlands, it flows about 500 mi (800 km) northwest through eastern Sudan to join the Nile River at Atbara in The Sudan. It is the Nile’s north¬ ernmost tributary.
Atchafalaya Na-.cha-fs-'lI-sX Bay Inlet of the Gulf of Mexico on the Louisiana coast, U.S. Together with Four League Bay, it extends about 21 mi (34 km). The Atchafalaya River links the bay with Morgan City on the Gulf Intracoastal Waterway. The area includes many natural gas and oil fields.
Atchafalaya River River, southern Louisiana, U.S. A distributary of the Red and Mississippi rivers, it branches southwest from the Red River in east-central Louisiana and flows south about 140 mi (225 km) to Atcha¬ falaya Bay. Its name is Choctaw for “Long River.”
Atchison, Topeka and Santa Fe Railroad Co. Former railway. Chartered in Kansas in 1860 by Cyrus K. Holliday, the founder of Topeka, as the Atchison and Topeka Railroad Co., it was built along the Santa Fe Trail and became known as the Santa Fe Railway. Its main line, completed in 1872, extended to the Colorado state border. Further expansion west in the 1880s and early 1890s reached about 9,000 mi (14,500 km) of track. It reached its greatest extent in 1941, with more than 13,000 mi (21,000 km) of track, but gradually shrank thereafter. In 1971 its famously luxu¬ rious passenger service was sold to Amtrak. In the 1990s it merged with Burlington Northern to become Burlington Northern Santa Fe Railway.
atelectasis X.at-T-'ek-ts-sssV or lung collapse Lack of expansion of pulmonary alveoli (see pulmonary alveolus). With a large-enough collapsed area, the victim stops breathing. In adhesive atelectasis, obstruction or lack of surface tension keeps a newborn’s alveoli from expanding. Com¬ pression atelectasis is caused by external pressure. Obstructive atelecta¬ sis may be caused by blockage of a major airway or when pain from abdominal surgery keeps breathing too shallow to clear bronchial secre¬ tions; treatment involves removal of obstruction or fluids, control of infec¬ tion, and lung reinflation.
Aten See Aton
Atget \at-'zhe\, (Jean-) Eugene (-Auguste) (b. Feb. 12, 1857, Liboume, near Bordeaux, France—d. Aug. 4, 1927, Paris) French pho-
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124 I Athabasca > Athos
tographer. He began his adult life as an itinerant actor. Around age 30 he settled in Paris and became a photographer. The rest of Atget’s life was spent recording everything he could that he considered picturesque or artistic in and around Paris. With an eye for strange and unsettling images, he made several series of photographs of iron grillwork, fountains, stat¬ ues, and trees. He also photographed shop fronts, store windows, and poor tradespeople. His main clients were museums and historical societies that bought his photographs of historic buildings and monuments. After World War I he received a commission to document the brothels of Paris. Man Ray published four of Atget’s photographs in La revolution surrealiste (1926), the only recognition he received in his lifetime. After his death, Ray, Berenice Abbott, and the art dealer Julien Levy bought his remaining collection, which is now in the Museum of Modem Art.
Athabasca, Lake Lake, western central Canada. It extends 208 mi (335 km), crossing the Alberta-Saskatchewan boundary. On the southwest it receives the Athabasca River, and on the northwest it discharges into the Slave River. It is important for its commercial fishing.
Athabasca River River, west-central Canada. A tributary of the Mac¬ kenzie River in Alberta, it rises in the Rocky Mountains in Jasper National Park and flows northeast and north 765 mi (1,231 km) into Lake Atha¬ basca. Its chief tributaries are the Pembina, Lesser Slave, McLeod, and Clearwater rivers. Extensive petroleum deposits lie in oil-impregnated sands (Athabasca Tar Sands) along a 70-mi (113-km) stretch of the river.
Athabaskan languages or Athapaskan languages Family of North American Indian languages. There are perhaps 200,000 speak¬ ers of Athabaskan. Northern Athabaskan includes more than 20 languages scattered across an immense region of subarctic North America from western Alaska to Hudson Bay and south to southern Alberta and British Columbia. Pacific Coast Athabaskan consisted of four to eight languages, all now extinct or nearing extinction. Apachean consists of eight closely related languages spoken in the southwestern U.S. and northern Mexico, including Navajo and the various subdivisions of Apache. In 1990 Navajo had some 150,000 speakers, far more than any other indigenous language of the U.S. or Canada. In 1915 Edward Sapir placed the Athabaskan fam¬ ily together with Tlingit and Haida (languages of Alaska and British Columbia, respectively) in a larger grouping called Na-Dene; this hypo¬ thetical relationship continues to be controversial.
Athanasius V.a-tho-'na-zhosN, Saint (b. 293, Alexandria, Egypt—d. May 2, 373, Alexandria; feast day May 2) Early Christian theologian and staunch opponent of Arianism. He studied philosophy and theology at Alexandria, Egypt, and in 325 he attended the Council of Nicaea, which condemned the Arian heresy. He welcomed the council’s teaching that the Son is “consubstantial with the Father” and defended that teaching throughout his career. In 328 he was appointed patriarch of Alexandria, but theological disputes led to the first of several banishments in 336. He returned from exile repeatedly and resumed his office, but Arian opposi¬ tion continued. After being banished by Constantius II in 356, Athanasius lived in a remote desert in Upper Egypt and wrote theological treatises, including his Four Orations Against the Arians. The emperor’s death in 361 gave Athanasius a brief respite under the toleration proclaimed by Julian, but a controversy with Julian’s heathen subjects forced him to flee into the Theban desert. At the time of his death he again possessed the see at Alexandria.
atheism Va-the-.iz-onA Critique and denial of metaphysical beliefs in God or divine beings. Unlike agnosticism, which leaves open the question of whether there is a God, atheism is a positive denial. It is rooted in an array of philosophical systems. Ancient Greek philosophers such as Dem¬ ocritus and Epicurus argued for it in the context of materialism. In the 18th century David Hume and Immanuel Kant, though not atheists, argued against traditional proofs for God’s existence, making belief a matter of faith alone. Atheists such as Ludwig Feuerbach held that God was a projection of human ideals and that recognizing this fiction made self-realization possible. Marxism exemplified modem materialism. Beginning with Friedrich Nietzsche, existentialist atheism proclaimed the death of God and the human freedom to determine value and meaning. Logical positivism holds that propositions concerning the existence or nonexistence of God are nonsensical or meaningless.
Athena \3-'the-n3\ or Athene \o-'the-ne\ In ancient Greek religion, the goddess of war, handicraft, and wisdom and the patroness of Athens. Her Roman counterpart was Minerva. Hesiod told how Athena sprang in full armour from Zeus’s forehead. In the Iliad she fought alongside the Greek
heroes, and she represented the vir¬ tues of justice and skill in warfare as opposed to the blood lust of Ares. She was associated with birds (especially the owl) and the snake, and she was usually represented as a virgin god¬ dess. Her birth and contest with Posei¬ don for suzerainty of Athens were depicted on the Parthenon. Her birth¬ day festival was the Panathenaea.
Athens Greek Athinai \a-'the-ne\
City (pop., 2001: 745,514), capital of Greece. It is located inland near its port, Piraeus, on the Saronic Gulf in eastern Greece. The source of many of the West’s intellectual and artistic conceptions, including that of democracy, Athens is generally con¬ sidered the birthplace of Western civilization. An ancient city-state, it had by the 6th century bc begun to assert its influence. It was destroyed by Xerxes in 480 bc, but rebuilding began immediately. By 450 bc, led by Pericles, it was at the height of its commercial prosperity and cultural and political dominance, and over the next 40 years many major build¬ ing projects, including the Acropolis and Parthenon, were completed.