Most of the running waters of Scotland, owing to the prevalence of mountain, and the frequent penetrations of the sea, have small length of course, and, even in the country itself, are not designated rivers. Yet though very numerous, and, for the most part, individually unimportant, they will be found distinctively noticed in the articles on counties, and fully described in the alphabetical arrangement. We can here, without useless repetition, only name the principal streams, and state their locality and direction of course. South of the west end of the Southern Highlands, or in two cases in Wigtonshire, and in the third between that county and Kirkcudbrightshire, the Luce, the Bladenoch, and the Cree, run south-eastward to the Irish sea. South of the main range of the Southern Highlands, the Dee, the Urr, the Nith, the Annan, and the Esk, run southward to the Solway frith. In the large triangular district, two sides of which are formed by the main range of the Southern Highlands, and by the long spur to St. Abb’s-head, and whose aggregate basin comprehends about 1,870 square miles, the Tweed, aided chiefly by the affluents of the Gala, the Teviot, and the Whitadder, runs east-ward, north-eastward, and northward, to the German ocean. The Lothians and the plain of Stirlingshire, are drained north-eastward or northward to the frith of Forth, principally by the Tyne, the Esk, the Leith, the Almond, the Avon, and the Carron. Ayrshire is drained in a direction more or less westerly to the frith of Clyde, by the Stinchar, the Girvan, the Doon, the Ayr, the Irvine, and the Garnock. The basin of the Clyde, comprehending an area of 1,200 square miles, is drained in a direction north of west to the head of the frith of Clyde, by its cognominal stream, whose chief affluents are the Douglas, the Avon, the Kelvin, and the Leven. The Forth, drawing greatly the majority of its head-waters from the central division of Scotland, fed principally by the Teith, the Allan, and the Devon, and draining an area of 574 square miles, flows eastward to its frith. The streams which, throughout both the central and the northern divisions of Scotland, run westward to the Atlantic, are all individually too inconsiderable to bear separate mention. Those which drain the district east of the Ochil-hills, are chiefly the Leven and the Eden, – the former eastward to Largo-bay, and the latter north-eastward to St. Andrew’s-bay. A vast territory lying immediately south of the great central range of mountains, and comprehending large portions of both the Highlands and the Lowlands, is drained to the extent of 2,396 miles, chiefly eastward, and partly southward, by the Tay and its tributaries, the principal of which are the Tummel, the Isla, the Almond, and the Earn. The north-east corner of this territory is drained eastward to the German ocean, chiefly by the South-Esk and the North-Esk. In the district immediately north of the central mountain-range, and east of the Cairngorm mountain-knot, the Dee and the Don run eastward to the sea at Aberdeen. In the district lying between this and the eastern half of the Moray frith, the Deveron runs north-ward to that frith, and the Ythan and the Ugie eastward to the German ocean. The district enclosed by the great central mountain-range, the north-east branch of the Cairngorm ramification, the Moray frith, and the Glenmore-nan-albin, is drained to the extent of 1,300 square miles, north-eastward to the sea by the Spey, to the extent of 500 miles northward to the frith by the Findhorn, and to a less extent for each stream, northward to the frith by the Nairn, and westward to Loch-Lochy, near the west end of the Glenmore by the Spean. In the great northern division of Scotland, the chief streams eastward are the Beauly to the head of the Beauly frith, the Conan to the head of the Cromarty frith, the Oykell to the head of the Dornoch frith, the Brora, the Helmsdale, the Berriedale, and the Wick; and the chief streams northward are the Thurso, the Forss, the Halladale, and the Naver. Of all the rivers, the Clyde alone is navigable by sea-craft for any considerable distance above the estuary; and even it possesses this high property only in consequence of great artificial deepening and embanking, and over a distance of but about 12 miles.