II.

The Land

The eastern coast of Ireland is comparatively regular and has few deep indentations; the western coast is fringed by drowned or submerged valleys, steep cliffs, and hundreds of small islands separated from the mainland by the powerful forces of the Atlantic. Topographically, the surface of the island may be described as basin-shaped. The chief physiographic features are a region of lowlands, occupying the central and east central sections, and a complex system of low mountain ranges, lying between the lowlands and the periphery of the island. Among the principal ranges are the Mourne Mountains in the north-east, rising 852 m (2,796 ft) above sea level; the mountains of Donegal in the north-west, containing Mount Errigal, 752 m (2,467 ft); the Sperrin Mountains in the north, containing Sawel Mountain, 683 m (2,240 ft); the Maumturk Mountains in the west, containing Mount Twelve Pins, 730 m (2,395 ft); the Caha Mountains in the south-west, containing Mount Knockboy, 707 m (2,321 ft); the Boggeragh Mountains in the south, rising to more than 640 m (2,100 ft); and the Wicklow Mountains in the east, rising more than 915 m (3,000 ft). Carrantuohill (1,041 m/3,414 ft above sea level), located in the south-western section of the island, is the highest point in Ireland. The central plain, or lowlands region, has maximum dimensions of about 160 km (100 mi) from east to west and about 80 km (50 mi) from north to south. Numerous bogs and lakes are found in the plain. The principal rivers of Ireland are the Erne and the Shannon, which are in reality chains of lakes joined by stretches of river. The northern portion of the central plain is drained by the Erne, and the centre of the plain is drained by the Shannon, which empties into the Atlantic Ocean through a wide, lengthy estuary. Nearly half of the Shannon, above the estuary, is made up of loughs Allen, Ree, and Derg. All the principal rivers of Ireland flow from the plain, and an interior canal system facilitates communications.

The climate of Ireland is typically insular. Because of the moderating influence of the prevailing warm, moist winds from the Atlantic Ocean, the mean winter temperature ranges from 4.4° to 7.2° C (40° to 45° F), approximately 14° C (25° F) higher than that of other places in the same latitude in the interior of Europe or on the eastern coast of North America. The oceanic influence is also very pronounced in summer, the mean summer temperature of Ireland, 15° to 16.7° C (59° to 62° F), being approximately 4° C (7° F) lower than that of other places in the same latitudes. The rainfall averages 1,016 mm (40 in) a year.

Most of the flora of Ireland comes via Britain from the western European mainland. Sedges, rushes, ferns, and grass are the principal flora. The Irish fauna does not differ markedly from that of Britain or France. The great Irish deer and the great auk, or garefowl, were exterminated in prehistoric times; and, subsequently, the island has lost its bear, wolf, wildcat, beaver, and native cattle. Remaining are the indigenous small rodents and birds of the woods, fields, and shoreline. The only reptile is the common lizard.