ANTRIM, a maritime co. in the n.e. of Ireland, in the province of Ulster; bounded, n., by the Atlantic; W., by the n. part of the river Bann, dividing it from Londonderry, and by lough Neagh; s., by Lagan river, separating it from the co. of Down; s.e., by Belfast lough; and e. by the Irish channel. It stands third among the Irish counties in population, but in extent only ninth. Its greatest length is 56 m.; its greatest breadth, 20; its extent of sea-coast, 90 m. Area, 1164 sq.m. About two thirds of this is arable; a fourth, barren; and a seventy-fourth in woods. Pop. in '51, 352,264; '61, 368,948; '71, 404,015, of whom 184,144 were Presbyterians, 108,835 Roman Catholics, 88,934 Episco palians, and the rest of other denominations. Off the n. coast lie Rathliu isle and the Sherries; and off the e. coast, the Maiden rocks. The e. coast is hilly; and from Larne to Fair Head, parallel mountain-ranges of no great height, and covering a third of the county, stretch s.w. into the interior, forming valleys opening seaward, called the glens of Antrim. The interior slopes towards lough Neagh. The highest eminences are Trostan, 1810 ft.; and Slievemish, or Slemish, 1782 ft. The principal streams are—the Bann, from lough Neagh to the Atlantic; the Main, running parallel to the Bann, but in the reverse direction, into lough Neagh; and the Bush, flowing n. into the Atlantic. Many peat-bogs occur in the county. Six sevenths of the surface consists of basaltic trap, often alternating with,red ochre, and overlying hardened chalk, green-sand, new red sandstone, and mica-slate. The surface and edges of the trap-field, in some places, present basaltic columns of varied outlines. The green-sand and new red sandstone crop out on the e. and s.e. borders, and millstone grit occurs in the n.e. Between Bally
castle and the mouth of the Bann, the basalt assumes very picturesque forms; and the Giants' causeway is one of the most perfect examples of columnar basalt in the world. Fine salt-mines occur at Duncrue and Carrickfergus; and small coal-fields near Bally castle and in the interior. Rich beds of iron ore of fine quality have been recently opened in Glenravel, and a large export has been carried on from Cushendall and Cara lough. The soil of A. is mostly light, and the chief crop is oats. In 1878, 246,498 acres were under crop, 81,760 being in oats, 45,831 in potatoes, and 5372 in wheat. The land is very much subdivided; and the rearing of flax, and the various branches of the linen, cotton, and coarse woolen manufacture, employ a great portion of the people. In 1878, there were cowards of 91,000 pupils on the rolls of the national schools in the county (22,000 being Catholics). The principal towns are—Belfast, Lisburn, Bally mena, Ballymoney, Carrickfergus, Larne, and Antrim. A. co. returns two mem bers to parliament; Belfast borough, two; and Carrickfergus and Lisburn boroughs, each one. The inhabitants ere mostly Presbyterians, the county having been extensively colonized from England and Scotland. The original possessors were the O'Neil's, who, partially dispossessed by John de Courcy, reappeared as chief, on the failure of his line, and in 1533 regained the whole country, except Carrickfergus and part of the glens— held by the Bissets of Glcnarm. The forfeiture of Shane O'Neill terminated the domin- • ion of his race.