The territory which forms the modern kingdom of Scotland is thus thrown by its leading physical features into three great compartments. First, the districts extending from the Solway, the Cheviots, and the Tweed, on the south, to the Firths of Forth and Clyde on the north; secondly, the low country extending along the east coast from the Forth as far as the Moray Firth, and lying between the sea and the great barrier of the Grampians; and thirdly, the Highland or mountainous region on the north-west.

Mountain chains.

In each of these great districts natural boundaries are again found exercising their influence on the subordinate political divisions. |The Cheviots.| In the first of these great compartments, the lofty range of the Cheviots, which forms the southern boundary and presents a steep face to the north, extends from the Cheviot Hill on the north-east by Carter Fell to Peel Fell on the south-west; and from thence a range of hills, sometimes included in the general name of the Cheviots, separates the district of Liddesdale from that of Teviotdale, and has its highest point in the centre of this part of the island, in a group of hills termed the Lowthers, where the four great rivers of the Tweed, the Clyde, the Annan, and the Nith, take their rise. From thence it extends westward to Loch Ryan, separating the waters which pour their streams into the Solway Firth from those which flow to the north. From the centre of this range a smaller and less remarkable chain of hills branches off, which, running eastward by Soutra and Lammermoor, end at St. Abb’s Head, at the entrance to the Firth of Forth, separating the tributaries of the Tweed from the streams which flow into the Firth of Forth. In the centre of the island, a barren and hilly region divides the districts watered by the rivers flowing into the east sea from those on the west coast.

The same natural boundary which separated the eastern from the western tribes afterwards divided the kingdom of the Strathclyde Britons from that of the Angles; at a subsequent period, the province of Galweia from that of Lodoneia in their most extended sense; and now separates the counties of Lanark, Ayr, and Dumfries from the Lothians and the Merse. Galloway in its limited sense was not more clearly separated by its mountain barrier on the north from Strathclyde, than were the Pictish from the British races by the same chain, and the earlier tribes of the Selgovæ and Novantæ from the Damnii.

In the other two great compartments situated on the north of the Firths of Forth and Clyde, two great mountain chains and two large rivers formed the principal landmarks in the early history of the social occupation of these districts. These two principal mountain chains were in fact the great central ridges from which the numerous minor chains proceed, and the rivers flow in opposite directions, forming that aggregate of well-watered glens and rocky defiles which characterise the mountain region of Scotland, till its streams, uniting their waters into larger channels, burst forth through the mountain passes, and flow through the more fertile plains of the Lowlands into the German Ocean.

The Mounth.

The first of these two great mountain chains was known by the name of the Mounth, and extends in nearly a straight line across the island from the Eastern Sea near Aberdeen to the Western Sea at Fort-William, having in its centre and at its western termination the two highest mountains in Great Britain—Ben-na-muich-dubh and Ben Nevis.

Drumalban.

The second great chain, less elevated and massive in its character, but presenting the more picturesque feature of sharp conical summits, crosses the other at right angles, running north and south, and forming the backbone of Scotland—the great wind and water shear, which separates the eastern from the western districts, and the rivers flowing into the German Ocean from those which pour their waters into the Western Sea. It is termed in the early records of Scottish history Dorsum Britanniæ, or Drumalban—the dorsal ridge or backbone of Scotland. It commences in Dumbartonshire, and forms the great separating ridge between the eastern and western waters from south to north, till it terminates in the Ord of Caithness.

These two mountain chains—the Mounth and Drumalban, the one running east and west, the other south and north, and intersecting each other—thus divided the country north of the Firths of Forth and Clyde into four great districts, two extending along the east coast, and two along the west, while each of the two eastern and western divisions were separated from each other by the Mounth. The two eastern divisions are watered by the two great rivers of the Tay and the Spey and their tributaries, the one flowing south and the other north from these mountain chains. The two western divisions are intersected by those arms of the sea or lochs, which form so peculiar a feature in the West Highlands.