IRELAND, called by the inhabitants Erin, and by the 'Welsh Yvcrdon, lies in the Atlantic Ocean, between 6° and 10° 40' West Longitude, and 15' and 55° 13' North Lati t.v.de. It is separated from Great Britain on the east by the Irish CI annel, which is also called St. George's Chan nel ; the latter appellation, however, is more commonly and particularly given to the southern entrance ; and the northern entrance is, strictly speaking, distinguished by the appellation of the North Channel. The Atlantic Ocean hounds it on all the other sides. The nearest land to it on the west is America ; on the south, Gallicia in Spain ; and on the north, the Hebrides. The Irish Channel varies very much in breadth ; generally speaking, it is narrowest at the two extremities, and broadest in the middle; the least breadth is between the Mull of Kintyre, in Argyle shire, and Torhead, in the county of Antrim ; the distance between these two places is about 16 miles.
Ireland is of an oblong shape, which, however, is bent from a straight line by the province of Munster ; for this province, instead of stretching itself first from the north to the south, and then from the south to the west, like the rest of the island, runs, in a sloping dii ection, from north east to south-west, and its western shores stretch farther into the sea than any other part of Ireland. Although Ireland is more compact in its form than flreat Britain, yet it is still irregular, narrowing from the middle, with various inequalities to the north-east and south-west ; “ contracting suddenly in the former direction, and then somewhat dilating, so as to make in that quarter a rounded peninsula ; in some degree gibbous on the south east, and of a serrated form on the south-west." From this account of its figure, it will be evident that its greatest length must be from the north-east to the south-west ; a line drawn between the two most distant points in these qua] ters, viz. Fairhead in the county of Antrim, and Mizenhead in the county of Cork, will mea sure 241 Irish, or rather more than 306 English statute miles. From Ernlah-rash, in the county of Mayo, to Carnsore-point, in the county of Wexford, is the greatest breadth of Ireland, being 163 Irish, or 207 English miles. The greatest length that can be drawn along a meridian, however, is not more than 185 Irish, or 235i English miles ; and the greatest breadth that can be measured nearly on a parallel of latitude is not more than 137 Irish, or 174 English miles. In consequence of the numerous and deep indentations of the sea on the west coast, there is not a spot in the kingdom 50 miles distant from the sea.
Geographers differ with regard to the superficial con tents of Ireland. Dr. Beaufort, from a computation made by carefully measuring the area of each county on the best maps, is of opinion that it contains considerably more than 18,750 square miles, or several thousand acres above 12 millions, Irish measure, which is equal to 30.370 English miles, or 19,436.000 English acres. Mr. Wakefield is of opinion that, including the inland lakes, the superficial con tents amount to 32,201 English square miles, of 15' to a degree ; or 12 722 615 Irish acres, or 20,437 974 Eng lish acres. Mr. Pinkerton, and some other geographers, reduce its contents below those assigned to it by Dr. Beaufort and Mr. Wakefield, and assign it only 27.457 squ re miles. -According to others, its contents amount to 11,067,712 Irish, or 17 927.864 English statute acres.
The progressive geogiaphy of Ireland presents little that is interesting. The map of Ptolemy is the most an cient geographical document of this island which we pos sess ; and, considering the period in which he lived, and compared with the maps and descriptions he has given us of countries at that time better known, it is distinguished for its correctness in the delineation of its general shape, and of its rivers, promontories, &c. The principal tribes mentioned by Ptolemy are, the Darni, on the north-east, and the Venicni and Rubogdii, on the north-west ; to the south of these he places the Nagnati, Auteri, and Gangani, on the west, the Erdini in the centre, and the Voluntii, Eblani, and Cauci, on the east ; and still further south, were the tribes of tree llenapii. Brigantes, Bodii, Ivelni, Velabri, and Luceni. This geographer also mentions ten• towns, of which the principal is Eblana, now Dublin. The geography of Ireland during the middle ages is more ob scure than it was in the time of Ptolemy ; at that period the Dalriadi occupied the north-east ; the Crutheni occu pied the north-west ; and a numerous tribe called the Neill seem to have occupied a large portion of the centre of the northern part of the island. Notwithstanding Ire land was first reduced under the subjection of the Eng lish in the reign of Henry II., it was little known till the time of Queen Elizabeth, when Stanihurst and Spencer published descriptions of it ; and even at this day the geography of its western counties is by no means perfect.