SCOTLAND, that portion of Great Britain which lies north of the English boundary; it also comprises the Outer and Inner Hebrides and other islands off the west coast, and the Orkney and Shetland islands off the north coast. With England lying to the south, it is bounded on the north and west by the Atlantic ocean and on the east by the North sea. It is separated from England by the Solway firth, the Sark, Scotsdyke (an old em bankment connecting the Sark with the Esk), the Esk (for one mile), the Liddel, the Kershope, the Cheviot hills, the Tweed and a small area known as the "liberties" of Berwick. The greatest length from Cape Wrath in Sutherland to the Mull of Galloway is 274 m., and the greatest breadth from Buchan Ness to Apple cross in the shire of Ross and Cromarty 154 m., but from Bonar Bridge at the head of Dornoch firth to the head of Loch Broom it is only 26 m. wide, and 3o m. from Grangemouth on the Forth to Bowling on the Clyde. The coast-line is estimated at 2,300 m., the arms of the sea being so numerous and in several cases pene trating so far inland that few places are beyond 4o m. from salt water. The total area is 19,069,50o ac. or 29,796 sq.m., exclu sive of inland waters (about 6o8 sq.m.), the foreshore (about 498 sq.m.) and tidal water (about 6o8 sq. miles).
The name Scotland (the ancient Caledonia—a name still poeti cally used) originated in the 11th century, when (from the tribe of Scots) part of it was called Scotia (a name previously applied to what is now Ireland) ; and the name of Scotland became estab lished in the 12th and 13th centuries.
Physically, Scotland is divided into three structural regions— le Highlands (subdivided by Glen More into the north-western Ind south-eastern Highlands) ; the central Lowlands (a tract of south-westerly to north-easterly trend, between a line drawn roughly from Girvan to Dunbar and a line drawn from Dumbar ton to Stonehaven) ; and the southern Uplands. To these, geogra phers add a fourth division, to be regarded as at least a sub-region of the Highlands, viz., the lower eastern slopes of that region bordering the North sea, from Stonehaven and Aberdeen in the south to the high plain of Caithness in the north. It may be termed the north-eastern region.
longitudinal valleys, which run in the same general direction as the ridges, have had their trend defined by geological structure, such as a line of dislocation (the Great Glen), or the plications of the rocks (Lochs Ericht, Tay and Awe, and most of the sea lochs of Argyllshire). The transverse valleys run north-west or south east and are for the most part independent of geological structure. The valley of the Garry and Tay crosses the strike of all the Highland rocks, traverses the great fault on the Highland border, and finally breaks through the chain of the Sidlaw hills at Perth. River-gorges are characteristic features in many of the valleys. In the Old Red Sandstone they are particularly prominent where that formation has lain in the way of the streams sweeping down from the Highlands. In the basin of the Moray firth some fine examples may be seen on the Nairn and Findhorn, while on the west side of the Cromarty firth some of the small streams descending from the high grounds of the east of the shire of Ross and Cromarty have cut out defiles in the conglomerates, remarkable for their depth and narrowness. Towards the south margin of the Highlands in stances of true canyons in the Old Red sandstone are to be seen where the Isla and North Esk enter that formation.
While many of the Highland mountains, viewed from near at hand, tower above the surrounding country, and are often of noble form, from a distance they are seen not to vary much from a general uniformity of height. A few exceptions occur along the western seaboard of Sutherland, in Skye, and elsewhere, but their structure explains the reason of their prominence. Regarded broadly, the Highland mountains are monuments of erosion, the relics of an old plateau, the surface and former slopes of which are shown approximately by the summits of the existing masses and the directions of the chief waterflows. The surface is rugged. The rocks project in bosses and crags, which roughen the sides and crests of the ridges. The shape and colour of these roughnesses depend on the nature of the underlying rock. Where it is hard and jointed, weathering into large quadrangular blocks, the hills are distinguished for the gnarled bossy character of their declivi ties, as may be seen in Ben Ledi and the heights to the north-east of it. Where, on the other hand, the rock decays into smaller debris, the hills assume smoother contours, as in the slate hills running from the Kyles of Bute to Loch Lomond.