Oskaloosa, capital of Mahaska county, Iowa, 104 miles WNW. of Burlington. It mines bituminous coal, and manufactures flour, woollens, boilers, electric appliances, etc. Here are Penn College (Quaker) and two others. Pop. 9558.
Osnabruck, a town in the Prussian province of Hanover, in the fertile valley of the Hase, 75 miles by rail SSW. of Bremen and 70 WSW. of Hanover. Its great Catholic cathedral, whose Bee was founded by Charlemagne about 810, and re-established in 1857, is in the Transition style of the first half of the 13th century, and rich in relics and monuments; the town-hall (1486-1512) contains portraits of all the plenipotentiaries who here on 24th October 1648 signed the peace of Westphalia. Osnabruck has important iron and steel works, and manufactures of railway plant, agricultural machinery, gas-meters, paper, tobacco, etc. Dating from 772, it suffered much in the Thirty Years' War, but recovered, thanks to its linen industry, during the 18th century. The name Osnaburgs given to coarse linens in England is derived hence. Pop. (1852) 13,718; (1900) 51,573, of whom one-third were Catholics.
Ossining, the name of what used to be called Sing-Sing (q.v.).
Ostero'de, a town of Hanover, at the western base of the Harz Mountains, on the Sose, an affluent of the Leine, 30 miles by rail NW. of Nordhausen. Its church of St Giles (724; rebuilt 1578) contains the graves of the Dukes of Grubenhagen, and there is also a fine town-hall. Pop. 6435. - Osterode, in East Prussia, on the Drewenz, 77 miles NE. of Thorn, has a castle of the Teutonic knights (1270). Pop. 13,170.
Ostia, a city of Latium, at the mouth of the Tiber, 14 miles SW. of Rome. It was a mere ruin in 830, when Gregory IV. founded a village - the modern Ostia - near the ancient one, whose ruins extend for a mile and a half along the Tiber.
Ostrau, the name of two neighbouring towns in Austrian Silesia, SO miles W. by S. from Cracow. Moravian Ostrau has extensive iron-works and other manufactures. Pop. 30,120. Polish Ostrau is the centre of a rich coalfield. Pop. 1S,760.