Geology and Minerals.— The central part of the county round Lough Allen is included in the Connaught coal-field, which both north and south is bounded by carboniferous limestone interspersed with millstone grit and Yoredale beds. In the southern districts there is a considerable extent of bog resting on marl or blue clay. The coal-fields consist of a series of eminences ranging from 1000 to 1377 feet, the most important beds being those to the west of Lough Allen near the Arigna. Only the lower measures remain, and they contain marine fossils. The coal is bituminous, and is well suited for manufacturing purposes; but it is not extensively wrought. In the Yoredale shales of the Coal-measures clay ironstone of a very rich quality is found, and was formerly smelted at the Arigna ironworks on Lough Allen. Lead has been found near Lurganboy, and copper in Benbo mountain. Manganese is obtained in considerable quantities, and also yellow ochre and various kinds of clays and chalks. The most important sulphureous spring is that of Drumsna; and the chalybeate springs of Cavan on the borders of the county, and of Oakfield adjoining the sea-coast, are also much visited.

Climate and Agriculture.— The climate is very moist and unsuitable for grain crops. On the higher districts the soil is stiff and cold, and, though abounding in stones, very retentive of moisture, but in the valleys there are some very fertile districts resting upon limestone. In the higher regions the chief implement of culture is the spade. Lime, marl, and similar manures are abundant, and on the coast seaweed is plentiful. The total number of holdings in 1880 was 1 4,812, of which only 624 were less than one acre. More than two-thirds of the holdings are included in those between 5 and 15 acres and between 15 and 30 acres, which numbered respectively 5439 and 5250. The following table shows the number of acres under the various crops in 1855 and 1881 :— [table]

The acreage under crops is thus less than one-fourth of the whole area. In 1880 there were 212,374 acres under pasture, and 78,330 waste. The number of horses in 1881 was 3983, of which 2627 were used for agricultural purposes. Between 1855 and 1881 cattle diminished from 91,061 to 84,914. The number of milch cows in the latter year was 35,732, the production of butter being one of the principal industries of the small farmer. Sheep diminished from 20,578 in 1855 to 11,347 in 1881, and pigs from 20,790 to 19,302. Poultry in 1881 numbered 311,920.

According to the corrected return of 1878 the land was divided among 451 owners possessing 371,371 acres, with a total annual valuation of £135,946. Of the owners about 70 per cent, possessed more than one acre, and the average value per acre was 7s. 3d. The average size of the estates is 823 acres; and the largest owners are Lord Massy, 24,751; Earl of Leitrim, 22,038; George Lane Fox, 18,850; Owen Wynne, 15,436; and Arthur L. Tottenham, 14,561.

Manufactures.— These are confined chiefly to coarse linens for domestic purposes, but coarse pottery is also made. In 1880 there were three scutching mills in the county, all driven by water.

Railways.— The Longford and Sligo branch of the Midland Great Western Railway passes through the southern part of the county, and in the northern part there is a branch between Sligo and Bundoran.

Administration and Population.— The county is divided into 5 baronies, and contains 17 parishes, with 1489 townlands. It is within the Connaught circuit, and assizes are held at Carrick-on-Shannon, and quarter sessions at Ballinamore, Carrick-on-Shannon, and Manorhamilton. There are two poor-law unions in the county and portions of other three. The county is within the Dublin military district, and there are barracks at Carrick-on-Shaunon. It is in the dioceses of Kilmore and Ardagh. In the Irish House of Commons two members were returned for the county and two for the boroughs of Carrick-on-Shannon and Jamestown, but at the union the boroughs were disfranchised. In 1760 the population was 26,142, which in 1821 had increased to 124,785 and in 1841 to 155,309, but in 1861 had diminished to 104,744, in 1871 to 95,562, and in 1881 to 89,795, of whom 44,777 were males and 45,018 were females. The total number of emigrants from the county between 1st May 1851 and 31st December 1880 was 43,186, a percentage of 41 *2 to the population in 1861. In 1880 the rate of marriages per 1000 of estimated population was 2∙6, of births 22 ’ 4, and of deaths 15 ’ 9. The population is almost entirely rural, the only town being Carrick-on-Shannon, with a population in 1871 of 1442.

History and Antiquities.— Anciently the entire country bordering on Lough Erne, including Fermanagh and Cavan, was, according to Ptolemy, occupied by the Erdini. Afterwards, along with Cavan” Leitrim formed part of the territory of Breffny or Brenny, which was divided into two principalities, of which Leitrim under the name of Hy Bnιin-BretΓny or Brenny formed the western. From the fact that for a long time it was possessed by the O’Rourks descendants of Roderick, king of Ireland, it was also called Breffny O’Rourk. In the 12th century Tiernan O’Rourk was expelled from the government by the princes of Leinster and Connaught, but he was afterwards reinstated by Turlough, king of Ireland, and, although after the arrival of the English it was united to Roscommon, the O’Rourks remained practically independent till the reign of Elizabeth. Large confiscations took place in the reigns of Elizabeth and J âmes I., in the Cromwellian period, and after the Revolution of 1688-S9.

There are “druidical” remains near Fenagh and at Letterfyan, and important monastic ruins at Creevelea near the Bonnet, with several antique monuments, and at Firnagh in the parish of l·enagh. There was an important Franciscan friary at Jamestown. The abbeys of Mohill, Annaduff, and Drumlease have been converted into parish churches. Among the more notable old castles are O’Rourk’s Hall at Dromahaire, now in ruins, Manorhamilton Castle, originally very extensive, but now also in ruins, and Castle John on an island in Lough Scur.