"COUNTY SLIGO, a maritime county in the province of Connaught, Ireland, is bounded N. by the Atlantic Ocean and Donegal Bay, E. by the counties of Leitrim and Roscommon, S. by Roscommon and Mayo, and W. by Mayo. It lies between 53° 53' and 54° 26' N. lat., 8° 3' and 9° 1' W. long. Its greatest length from E. to W. is 41 miles, and from N. to S. 38 miles. Its area is 721 square miles, or 461,753 acres, of which 290,696 acres are arable, 151,723 uncultivated, 6,134 in plantations, 460 sites of towns and villages, and 12,740 underwater. The population in 1841 was 180,809, in 1851, 128,510, and in 1861, 124,845, or 173 to every square mile of the entire surface, being only 69 per cent. of the number in 1841, when there were 251 to every square mile. The number of persons from this county who emigrated from Irish ports, stating it-was their intention not to return, from the 1st May, 1851, to the 31st December, 1864, was 17,693, or nearly 13 per cent. of the population at the former date. The coast line of Sligo is nearly 100 miles in extent, and is irregular in outline, forming many bays and natural harbours, of which the most important are Ballysadare and Sligo Bays, and terminating at other parts in rocky headlands, among which are Rathlee Dead to the E. of Killala Bay, Aughris Read to the S. of Sligo Bay, and Rosskeeragh Point. The coast is generally rocky, but to the E. of Sligo Bay and at Killala Bay sandy and pebbly strands prevail. The principal islands are Inishmurray, about a mile in length, containing 209 acres, with a population in 1861 of 58, and Inishmulclohy, or Coney Island, which lies at the entrance of Sligo Bay, and forms a natural breakwater.
Sligo formerly belonged to the O'Conor family, and the descendants of Roderick O'Conor were long engaged in many struggles in defence of their patrimony. Upon the invasion of Henry II. a Norman family named De Burgo established themselves here, and assisted Charles Carragh in depriving his kinsman Cathal of the Bloody Hand of the throne of Connaught. Hugh O'Nial, head of the Tyrone family, supported Cathal, and was signally defeated at Ballysadare in 1200. In 1245 Maurice Fitzgerald, then Lord Deputy, built a castle on the present site of Sligo town. In the rebellion of 1641 the county suffered severely, and was finally overrun and subdued by the Cromwellian army under General Ireton and Sir Charles Coote. It was faithful to James II., and in the disturbances of 1798 it was again the theatre of military movements, which, however, were unattended with any decisive result. This county has a great diversity of, surface, exhibiting rich plains, lakes, mountains, and wooded enclosures, and in other parts dreary expanses of bog and commons. Entering from Ballyshannon, the land along the coast is flat and bleak, but is much relieved by the elevations of Benbulben, Benduff, and Benwisken; these form part of a range of limestone mountains stretching eastward, which, with their smooth flat tops, present a strange contrast to the rough gneiss mountains which lie around. At the southern base of Knocknarea, 1,078 feet high, is a chasm, called the Glen of Knocknarea, three-quarters of a mile long, and 30 feet broad. Its sides, which rise to a height of 40 feet, are almost perpendicular, and present the appearance of ashlar masonry. From this point, along the coast to Killala Bay, stretches an extensive plain backed by lofty mountains, reaching from Ballysadare to Foxford in County Mayo, a distance of 25 miles, and is for the most part 5 to 6 miles in breadth. These mountains consist of two parallel divisions, called Slieve Gamph and the Ox mountains, and vary in height from 600 to nearly 1,800 feet, their northern surface being generally abrupt and rocky. Along the borders of Roscommon are the Curlew hills, of which Carrowkeel has an elevation of 1,062 feet, and Keshcorran of 1,183 feet. The Braughlieve mountains belong principally to Roscommon and Leitrim, but extend also into this county, where they rise to a height of 1,183 feet. The lakes are Loughs Talt and Easky, which lie between Slieve Gamph and the Ox mountains, Loughs Arrow and Gara, both bordering on Roscommon, and Lough Gill, about 6 miles long and 2 in breadth, stretching from Sligo town to county Leitrim. The last named is 20 feet above the sea-level at low-water, and is the largest, containing among other islets Innismore, called also Church Island, upon which are the remains of a monastery. There is no river of importance in the county, but the principal stream is the Owengarrow, which takes its rise in the Ox mountains, and flows southward into county Mayo, where it joins the Moy, which for a part of its course forms the boundary of this county. The Arrow, coming from Lough Arrow, empties itself into Ballysadare Bay after receiving in its course the waters of the Owenmore from the Curlew mountains, and the Owenbeg from the Ox mountains. The Garrogue from Lough Gill flows through the town of Sligo into the bay. The principal roads are the mail-road from Dublin to Sligo, which is continued to Ballina, and the mail-road to Ballyshannon. A branch line of the Midland Great Western railway has been made from Mullingar to Sligo, passing through Longford. Most of the county belongs to the carboniferous limestone formation, interspersed with large tracts of Old Red sandstone, and in some places mica slate, trap, hornblende, and gneiss are met with, especially in the Ox mountains, which also abound in minerals, as ironstone, copper, lead, and silver, all which were formerly worked in considerable quantities, but on the failure of the supply of wood the furnaces gradually declined. Manganese occurs in the mountains bordering on Leitrim, and garnets are found near Lough Easky, also asbestos in the neighbourhood of Leitrim, and amethysts near Ballymote. The climate is generally temperate and healthy, but variable, and the influence of the Atlantic is felt in frequent rains, often accompanied by high winds. The soil is generally good, and well suited for agriculture. In the district to the N.E. of Sligo mossy and sandy soils prevail, and the sea at this point was making serious inroads upon the land, and had covered several hundred acres of fertile ground, when the late Lord Palmerston, part of whose Irish property lies along the coast, and some other landowners succeeded in stopping the encroachments. Approaching the town of Sligo the soil is less mossy, deeper, and richer, and the plain lying to the S. of the town, and resting on a subsoil of limestone or calcareous gravel, is the best land in the county. Diversified occasionally with bog and peat, it extends as fir as the Curlew and Braughlieve mountains, along the sides of which are dreary moorlands. In most parts of this district a substratum called lac-leigh, or grey flag, is found, which is singularly retentive of water, and does not allow it to pass through. It lies about 9 to 12 inches below the surface, and on being broken up and mixed with the surrounding earth acts as a fertiliser, and no longer interferes with the drainage. From this central plain, stretching across to Mayo, is a gently undulating country, the inner part abounding in moor and deep moss. The occupations of the people are chiefly agricultural, and large districts are laid out in tillage, but grazing also is extensively practised. The total number of acres under crop in 1865 was 96,675, being an increase of 16,963 acres since 1848; and 221,140 acres, exclusive of clover and meadow, were in grazing land. In 1841 there were 7,360 acres under plantation of oak, beech, elm, ash, fir, mixed timber, and fruit. The fisheries on the coast are of considerable importance, and trout, salmon, and other fish are taken in the rivers. The oysters are large in size, but well flavoured, being chiefly procured from the beds at Lissadill. Coarse woollens and linens are manufactured to a small extent. The religion of the people is principally Roman Catholic, 112,436, or 90 per cent. of the entire population, having, in 1861, been of that persuasion, while 10,438, or 8.4 per cent., belonged to the Established Church, and 1,971, or 1.6 per cent., were of other Christian denominations, of whom 931 were Presbyterians, and 778 were Methodists. The county is divided for civil purposes into 6 baronies -Carbury, Coolavin, Corran, Leyney, Tireragh, and Tirerril, and contains 41 parishes. It returns 3 members to parliament, 2 for the county, the constituency in 1861 having been 3,181, and 1 for the borough, constituency 379. It belongs to the Connaught circuit. Sligo is the only town in the county with a population, in 1861, over 2,000, and is the assize town. Markets are held there, and also at Aclare, Ballymote, Bellaghy, Easky, and Tobereurry. The county infirmary, county gaol, and the district lunatic asylum for this county and Leitrim are at Sligo. Quarter sessions are held here, and also at Easky and Ballymote. Petty sessions are held at 14 places. The local government is vested in the lieutenant of the county and custos rotulorum, the sheriffs, 14 deputy lieutenants, and about 88 magistrates. The county belongs to the northern, or Dublin military district, and there are barracks at Sligo. In the neighbourhood of Sligo are many Druidical remains, and at a place called Lug-na-Clough, or the Giant's Grave, many immense stones stand perpendicularly in a strange and unaccountable manner, forming part of a circle similar to that at Stonehenge on Salisbury Plain, in England."