"ROSCOMMON, an inland county of the province of Connaught, Ireland. It lies between 53° 16' to 54° 7' N. lat., and from 7° 50' to 8° 46' W. long. It is bounded on the E. by the river Shannon, on the S. and S.W. by county Galway, on the W. by counties Galway and Mayo, on the N. by Sligo, and on the N.E. by Leitrim. It is 60 miles long, and its greatest breadth is 37 miles, comprising an area of 607,691 acres, of which 440,522 are in cultivation, 132,299 uncultivated, 768 occupied by the sites of towns, villages, and roads, 29,370 under water, and 6,732 in plantations. The general character of the surface is undulating or flat, except towards the N., where it becomes mountainous. The Curlew Mountains in the N.W., the Slievebawn range in the W., the Braulieve or Braughlieve on the Leitrim border, and some hills which skirt Lough Allen in the N., are the principal elevations, some of the summits attaining a height of 1,000 to 1,200 feet above the sea level. The principal rivers are the Suck and Shannon; the former traverses the N. boundary, and the latter drains it on the E. The lakes are numerous, and constitute a leading feature in this part of the island; Loughs Key, Garra, Skean, Meelagh, Aelagh, Erritt, and Glynn are the principal waters. The numerous small lakes are sometimes connected in a continued chain for great distances, but are not navigable. There are several turloughs, which leave most luxuriant soil behind them in the summer.
The prevailing subsoil is limestone, but silicious sandstone crops up frequently in different parts. The most important geological formations are those belonging to the great carboniferous limestone district of central Ireland, and in the northern part of the county they include a considerable coal field with three beds of coal, and resting on beds of the millstone-grit series, known as the Arigna district. Iron ore is worked here, and extensive smelting and casting operations are carried on, also potters' fire and pipe clays are obtained indifferent parts. The Curlew Mountains consist of the Old Red sandstone formation, and the Braulieve of shales and sandstones. The soil in the level limestone districts is very fertile, but the bogs in the uplands are numerous. Agriculture is in a backward state, and the poorer classes of the inhabitants are extremely wretched. There are few dairies, though the pastures are luxuriant. The principal crops are oats, wheat, and potatoes. The breeds of cattle and sheep are good; the former long horned, and the latter long woolled. A wide field for reclamation presents itself among the extensive bogs and wastes. This county comprises nine baronies-Athlone, North and South Ballintober, Ballymoe, Boyle, Castlereagh, Frenchpark, Moycarn, and Roscommon, which together include 58 parishes. The population in 1851 was 173,798, and in 1861 100,000. The principal towns are Roscommon, Boyle, and Elphin. The county sent eight members to parliament before the Union, but now it has only two representatives for the county at large. The linen manufacture was at one time extensively diffused over the county, but it is now nearly extinct. Roscommon is included within the Connaught circuit, the assizes being held at Roscommon. The government is entrusted to a lord-lieutenant, assisted by 10 deputy-lieutenants, besides magistrates, coroners, &c. There are 54 police stations, with about 300 men. Athlone, Athleague, Ballagb, Boyle, Castlerea, Croghan, Elphin, and Tulsk have dispensaries. It is in the western military district, and contains 3 barrack stations. The ancient inhabitants of Roscommon are said to have been the Auterii; subsequently the county was divided among the O'Connors in the midland, the MacDermots in the northern, and the O'Kellies in the southern districts. Notices of the Sheriff of Roscommon are found as early as Edward I. The county lies partly within the dioceses of Elphin, Tuam, and Clonfert. There are numerous raths and various monastic remains, some of considerable interest."