Ireland is divided territorially into four provinces and thirty-two counties:—(a) Ulster (northern division): Counties Antrim, Armagh, Cavan, Donegal, Down, Fermanagh, Londonderry, Monaghan, Tyrone. (b) Leinster (eastern midlands and south-east): Counties Carlow, Dublin, Kildare, Kilkenny, King’s County, Longford, Louth, Meath, Queen’s County, Westmeath, Wexford, Wicklow. (c) Connaught (western midlands): Counties Galway, Leitrim, Mayo, Roscommon, Sligo. (d) Munster (south-western division): Counties Clare, Cork, Kerry, Limerick, Tipperary, Waterford.
Physical Geography.—Ireland stands on the edge of the European “continental shelf.” Off the peninsula of Mullet (county Mayo) there are 100 fathoms of water within 25 m. of the coast which overlooks the Atlantic; eastward, northward and southward, in the narrow seas, this depth is never reached. The average height of the island is about 400 ft., but the distribution of height is by no means equal. The island has no spinal range or dominating mountain mass. Instead, a series of small, isolated clusters of mountains, reaching from the coast to an extreme distance of some 70 m. inland, almost surrounds a great central plain which seldom exceeds 250 ft. in elevation. A physical description of Ireland, therefore, falls naturally under three heads—the coasts, the mountain rim and the central plain.
The capital city and port of Dublin lies a little south of the central point of the eastern coast, at the head of a bay which marks a sudden change in the coastal formation. Southward from its northern horn, the rocky headland of Howth, the coast is generally steep, occasionally sheer, and the mountains of county Coasts. Wicklow approach it closely. Northward (the direction first to be followed) it is low, sandy and fringed with shoals, for here is one point at which the central plain extends to the coast. This condition obtains from 53° 25′ N. until at 54° N. the mountains close down again, and the narrow inlet or fjord of Carlingford Lough separates the abrupt heights of the Carlingford and Mourne Mountains. Then the low and sandy character is resumed; the fine eastward sweep of Dundrum Bay is passed, the coast turns north again, and a narrow channel gives entry to the island-studded lagoon of Strangford Lough. Reaching county Antrim, green wooded hills plunge directly into the sea; the deep Belfast Lough strikes some 10 m. inland, and these conditions obtain nearly to Fair Head, the north-eastern extremity of the island. Here the coast turns westward, changing suddenly to sheer cliffs, where the basaltic formation intrudes its strange regular columns, most finely developed in the famous Giant’s Causeway.
The low land surrounding the plain-track of the Bann intervenes between this and the beginning of a coastal formation which is common to the north-western and western coasts. From the oval indentation of Lough Foyle a bluff coast trends north-westward to Malin Head, the northernmost promontory of the island. Thence over the whole southward stretch to Mizen Head in county Cork is found that physical appearance of a cliff-bound coast fretted with deep fjord-like inlets and fringed with many islands, which throughout the world is almost wholly confined to western seaboards. Mountains impinge upon the sea almost over the whole length, sometimes, as in Slieve League (county Donegal), immediately facing it with huge cliffs. Eight dominant inlets appear. Lough Foyle is divided from Lough Swilly by the diamond-shaped peninsula of Inishowen. Following the coast southward, Donegal Bay is divided from Galway Bay by the hammer-like projection of county Mayo and Connemara, the square inlet of Clew Bay intervening. At Galway Bay the mountain barrier is broken, where the great central plain strikes down to the sea as it does on the east coast north of Dublin. After the stern coast of county Clare there follow the estuary of the great river Shannon, and then three large inlets striking deep into the mountains of Kerry and Cork—Dingle Bay, Kenmare river and Bantry Bay, separating the prongs of the forklike south-western projection of the island. The whole of this coast is wild and beautiful, and may be compared with the west coast of Scotland and even that of Norway, though it has a strong individuality distinct from either; and though for long little known to travellers, it now possesses a number of small watering-places, and is in many parts accessible by railway. The islands though numerous are not as in Scotland and Norway a dominant feature of the coast, being generally small and often mere clusters of reefs. Exceptions, however, are Tory Island and North Aran off the Donegal coast, Achill and Clare off Mayo, the South Arans guarding Galway Bay, the Blasquets and Valencia off the Kerry coast. On many of these desolate rocks, which could have afforded only the barest sustenance, there are remains of the dwellings and churches of early religious settlers who sought solitude here. The settlements on Inishmurray (Sligo), Aranmore in the South Arans, and Scattery in the Shannon estuary, had a fame as retreats of piety and learning far outside Ireland itself, and the significance of a pilgrimage to their sites is not yet wholly forgotten among the peasantry, while the preservation of their remains has come to be a national trust.
The south coast strikes a mean between the east and the west. It is lower than the west though still bold in many places; the inlets are narrower and less deep, but more easily accessible, as appears from the commercial importance of the harbours of Cork and Waterford. Turning northward to the east of Waterford round Carnsore Point, the lagoon-like harbour of Wexford is passed, and then a sweeping, almost unbroken, line continues to Dublin Bay. But this coast, though differing completely from the western, is not lacking in beauty, for, like the Mournes in county Down, the mountains of Wicklow rise close to the sea, and sometimes directly from it.
Every mountain group in Ireland forms an individual mass, isolated by complex systems of valleys in all directions. They seldom exceed 3000 ft. in height, yet generally possess a certain dignity, whether from their commanding position or their bold outline. Every variety of form is seen, from steep Mountains. flat-topped table-mountains as near Loughs Neagh and Erne, to peaks such as those of the Twelve Pins or Bens of Connemara. Unlike the Scottish Highlands no part of them was capable of sheltering a whole native race in opposition to the advance of civilization, though early customs, tradition and the common use of the Erse language yet survive in some strength in the wilder parts of the west. From the coasts there is almost everywhere easy access to the interior through the mountains by valley roads; and though the plain exists unbroken only in the midlands, its ramifications among the hills are always easy to follow. Plain and lowland of an elevation below 500 ft. occupy nearly four-fifths of the total area; and if the sea were to submerge these, four distinct archipelagos would appear, a northern, eastern, western and south-western. The principal groups, with their highest points, are the Mournes (Slieve Donard, 2796 ft.) and the Wicklow mountains (Lugnaquilla, 3039) on the east; the Sperrins (Sawel, 2240) in the north; the Derryveagh group in the north-west (Errigal, 2466); the many groups or short ranges of Sligo, Mayo and Galway (reaching 1695 ft. in the Twelve Pins of Connemara); in the south-west those of Kerry and Cork, where in Carrantuohill or Carntual (3414) the famous Macgillicuddy Reeks which beautify the environs of Killarney include the highest point in the island; and north-east from these, the Galtees of Tipperary (3018) and Slieve Bloom, the farthest inland of the important groups. Nearer the south coast are the Knockmealdown (2609) and Commeragh Mountains (2470) of county Waterford.
It will be realized from the foregoing description that it is impossible to draw accurate boundary lines to the great Irish plain, yet it rightly carries the epithet central because it distinctly divides the northern mountain groups from the southern. The plain is closely correlated with the bogs Central plain. which are the best known physical characteristic of Ireland, but the centre of Ireland is not wholly bog-land. Rather the bogs of the plain are intersected by strips of low-lying firm ground, and the central plain consists of these bright green expanses alternating with the brown of the bogs, of which the best known and (with its offshoots) one of the most extensive is the Bog of Allen in the eastern midlands. But the bogs are not confined to the plain. They may be divided into black and red according to the degree of moisture and the vegetable matter which formed them. The black bogs are those of the plain and the deeper valleys, while the red, firmer and less damp, occur on the mountains. The former supply most of the peat, and some of the tree-trunks dug out of them have been found so flexible from immersion that they might be twisted into ropes. Owing to the quantity of tannin they contain, no harmful miasma exhales from the Irish bogs.
The central plain and its offshoots are drained by rivers to all the coasts, but chiefly eastward and westward, and the water-partings in its midst are sometimes impossible to define. The main rivers, however, have generally a mountain Rivers. source, and according as they are fed from bogs or springs may be differentiated as black and bright streams. In this connexion the frequent use of the name Blackwater is noticeable. The principal rivers are—from the Wicklow Mountains, the Slaney, flowing S. to Wexford harbour, and the Liffey, flowing with a tortuous course N. and E. to Dublin Bay; the Boyne, fed from the central plain and discharging into Drogheda Bay; from the mountains of county Down, the Lagan, to Belfast Lough, and the Bann, draining the great Lough Neagh to the northern sea; the Foyle, a collection of streams from the mountains of Tyrone and Donegal, flowing north to Lough Foyle. On the west the rivers are generally short and torrential, excepting the Erne, which drains the two beautiful loughs of that name in county Fermanagh, and the Shannon, the chief river of Ireland, which, rising in a mountain spring in county Cavan, follows a bow-shaped course to the south and south-west, and draws off the major part of the waters of the plain by tributaries from the east. In the south, the Lee and the Blackwater intersect the mountains of Kerry and Cork flowing east, and turn abruptly into estuaries opening south. Lastly, rising in the Slieve Bloom or neighbouring mountains, the Suir, Nore and Barrow follow widely divergent courses to the south to unite in Waterford harbour.