Autun (ō-tu˙n; ancient, Bibracte, later, Augustodunum), a town, South-Eastern France, department of Saône-et-Loire. It has two Roman gates of exquisite workmanship, the ruins of an amphitheatre and of several temples, the cathedral of St. Lazare, a fine Gothic structure of the twelfth century with chapels added in the fifteenth; manufactures of carpets, woollens, cotton, velvet, hosiery, &c. Pop. 15,498.
Autunite, a hydrous phosphate of uranium and calcium, crystallizing in the rhombic system in yellow plates. Like other minerals of the uranium series it shows radio-activity.
Auvergne (ō-vār-nyė), a province, Central France, now merged into departments Cantal and Puy-de-Dôme, and an arrondissement of Haute-Loire. The Auvergne Mountains, separating the basins of the Allier, Cher, and Creuse from those of the Lot and Dordogne, contain the highest points of Central France: Mount Dor, 6188 feet; Cantal, 6093 feet, and Puy-de-Dôme, 4806 feet. The number of extinct volcanoes and general geologic formation make the district one of great scientific interest. The minerals include iron, copper, and lead, and there are warm and cold mineral springs. Auvergne contributes a large supply to the labour markets of Paris and Belgium, there being in Paris alone some 50,000 Auvergnats.
Auxerre (ō-sār), a town, France, department of Yonne, 110 miles S.E. of Paris. Principal edifices: a fine Gothic cathedral, unfinished; the abbey of St. Germain, with curious crypts; and an old episcopal palace, now the Hôtel de Prefecture; it manufactures woollens, hats, casks, leather, earthenware, violin strings, &c.; trade, chiefly in wood and wines, of which the best known is white Chablis. Pop. 21,930.
Auxom´eter, an instrument to measure the magnifying powers of an optical apparatus.
Auxonne (ō-son; ancient, Aussona), a town, France, department of Côte-d'Or (Burgundy), on the Saône; a fortified place, with some manufactures. Pop. 6300.
A´va, a town in Asia, formerly the capital of Burma, on the Irawadi, now almost wholly in ruins.
Ava-Ava, Arva, Kava, or Yava (Macropiper methysticum), a plant of the nat. ord. Piperaceæ (pepper family), so called by the inhabitants of Polynesia, who make an intoxicating drink out of it. Its leaves are chewed with betel, in South-Eastern Asia.
Avad´avat. See Amadavat.
Av´alanches, large masses of snow or ice precipitated from the mountains, and distinguished as wind or dust avalanches when they consist of fresh-fallen snow whirled like a dust-storm into the valleys; as sliding avalanches when they consist of great masses of snow sliding down a slope by their own weight; and as glacier or summer avalanches when ice-masses are detached by heat from the high glaciers.