Ainsworth, William Francis, an English physician, geologist, and traveller, born 1807. He was surgeon and geologist to the Euphrates expedition under Colonel Chesney, and published Researches in Assyria, Babylonia, and Chaldæa (1838); Travels in Asia Minor, Mesopotamia, and Armenia (1842); Travels in the Track of the Ten Thousand Greeks (1844), &c. Died 1896.
Ainsworth, William Harrison, an English novelist, born 1805, died 1882. He was the son of a Manchester solicitor and intended for the profession of law, but devoted himself to literature. He wrote Rookwood (1834), Jack Sheppard, illustrated by Cruickshank (1839), and about forty other novels, including Guy Fawkes, Tower of London, Windsor Castle, Lancashire Witches, Flitch of Bacon, &c. His literary models were at first Sir Walter Scott and afterwards Victor Hugo's Nôtre Dame de Paris.
Ain-Tab (a˙-in-täb′), a town of Northern Syria, 60 miles north of Aleppo; with manufactures of cottons, woollens, leather, &c., and an extensive trade. There is here an American Protestant mission. Pop. 45,000.
Ainu. See Ainos.
Air, the gaseous substance of which our atmosphere consists, being a mixture mainly of about 78 per cent by volume of nitrogen and 21 per cent of oxygen. The latter is absolutely essential to animal life, while the purpose chiefly served by the nitrogen appears to be to dilute the oxygen. Oxygen is more soluble in water than nitrogen, and hence the air dissolved in water contains about 10 per cent more oxygen than atmospheric air. The oxygen therefore available for those animals which breathe by gills is somewhat less diluted with nitrogen, but it is very much diluted with water. For the various properties and phenomena connected with air see such articles as Atmosphere, Aeronautics, Air-pump, Barometer, Combustion, Respiration, &c.
Air, in music (in It. aria), a continuous melody, in which some lyric subject or passion is expressed. The lyric melody of a single voice, accompanied by instruments, is its proper form of composition. Thus we find it in the higher order of musical works; as in cantatas, oratorios, operas, and also independently in concertos.—Air is also the name often given to the upper or most prominent part in a concerted piece, and is thus equivalent to treble, soprano, &c.
Aïr, or Asben. See Asben.
Aira. See Hair-grass.
Air Beds and Cushions, often used by the sick and invalids, are composed of india-rubber or of cloth made air-tight by a solution of india-rubber, and when required for use filled with air, which thus supplies the place of the usual stuffing materials. They tend to prevent bed-sores from continuous lying in one position. They are also cheap and easily transported, as the bed or cushion, when not in use, can be packed in small compass, to be again inflated with air when wanted.
Air-bladder. See Swimming-bladder.