GREAT BRITAIN. 164 GREAT BRITAIN. vulsion. The mountains are not so high as those of Scotland. It may be said of the island as a whole that it becomes lower and flatter as it widens out toward the south. The main direc- tion of the mountain ranges of England and Wales is from north to south or from northeast to southwest, and they thus interpose no ob- stacles to communication with the Scottish Low- lands except among the Cheviot Hills which, ex- tending along the border, belong to Scotland more than to England, and hel])ed Scotland long to maintain a separate political existence. The rail- road connections between England and Scotland are still mainly around the ends of the Cheviots through Carlisle and Berwick. The Cheviot Hills are separated from the Pen- nine Chain by a low strip through which there is easy railroad communication across North Eng- land between Carlisle and Newcastle. The Pen- nine Chain is a succession of moors and hills of Carboniferous formation, the latter from 1000 to 2900 feet high, the backbone of Northern Eng- land, extending south 150 miles, and forming the water parting between east and west flowing rivers. On both sides of the chain the coal meas- ures come to the surface of the plain, forming the coal-fields of Lancashire and Stafl'ordshire on the west and of Yorkshire on the east. The Cumbrian group of mountains, a region also known as the English Lake District, is in the northwest of England, and is joined to the Pennines by the high moorland of Shap Fell. This ring of peaks, rising to over 3000 feet, is in its scenic aspects the grandest and most beauti- ful part of England. Its deep valleys have been eroded from the original high plateau of igneous and old sedimentary rocks, and in these valleys are the long, narrow lakes that have made this district famous for its picturesque charm. The Welsh or Cambrian moimtains. in which the Welsh tribes were long able to maintain an inde- pendent and separate existence, cover Wales, and are mostly of very old sedimentary strata with crystalline rocks at various points. A wide band of coal measures in tlie south forms the great coal-field of Wales. Unlike the Scottish High- lands, these mountains do not impart great rug- gedness to the coast, because the rivers have brought down vast quantities of sediment, spread- ing it out into delta plains and largely filling the fiords that formerly existed. The high peninsula ■of Devon and Cornwall, forming the extreme southwestern extension of England, is the fifth and last feature of the highlands of South Brit- ain. It is sejiarated from Wales by the Bristol Channel, while another great depression on the south, the English Channel, severs it from Brit- tany, France, with which it is closely related in its crystalline and primary rocks, its high, un- fertile moorland, and its climate. To the southeast of this great highland region extend the fertile lowlands of England, less than .oOO feet above sea-level as a ride, comparatively flat, composed of younger sedimentary (Jle.sozoic and Tertiary-) rocks, the harder of which stand above the general level, fornung several bands of higher ground, the oolitic and chalk bands be- ing most prominent. The oolitic belt of higher ground extends to the northeast from Portland Bill in the soith to Whitby in the north, form- ing, among the various elevations, the Cotswold Hills and the north Yorkshire moors, the latter, nearly 1500 feet in height, being the loftiest part of the plain region of England. Directly east of this Jurassic formation and extending parallel with it is the chalk country, whose ridges of hills form the Salisbury plateau, the Chiltern Hills, and other elevations. These chalk heights also extend along the south of England (the North and South Downs ) , and are seen in the wliite clifi's fronting the English Channel and abutting on the North Sea in the North and .South Forelands. Between the North and South Downs, the weald, once heavily wooded, wedge-shaped, penetrates westward from the North Sea; and between the north extending chalk lands and the North Sea extends the London Basin, low, remarkably fertile, whose coast is broken by several estuaries, among which that of the Thames is most prominent. One more distinc- tive feature, about midway on the east coast of England, is the marsliy expanse of the Fenland. lying almost at the level of the sea. This great plain of England, with its diversified formations, is preeminently the agricultural region of Great Britain. Hydrography. The water parting is situated much nearer the west than the east coast, with the result that the larger number of rivers flow to the east : with the exception of the western Severn, the eastern rivers are the longest, and their basins larger than the western basins. As the eastern rivers of England flow sluggishly down the gentle slope of the plain lands, it is nat- ural that they should be least liable to floods and most important for navigation. Their value for comftierce is somewhat impaired, however, by the fact that, crossing the softer rocks of the plain, they carry down a great deal of alluvium with which their mouths are often seriously clogged. The Tyne, Wear, and Tees of Northeast England have a course of only 70 or 80 miles, and their commercial importance depends upon the great coal-fields (Tyne and Wear) and the iron and salt deposits (Tees) near them. The basin of the Humber embraces 10.000 square miles, from the mineral beds of the Pennine slopes through the rich agricultural plains ; the Aire, Ouse, Trent, and other tributaries help to make it one of the most useful river systems in Eng- land. The Thames rises only .300 feet above the sea, but it has a long course of about 200 miles. Its sluggish current, its well-protected estuary, and the tides which carry the largest ocean vessels 50 miles up to London Bridge, help to make the Thames one of the largest commerce-carriers among the world's rivers. The important western rivers of South Britain are limited to the Severn and the Mersev. The Severn is the longest Brit- ish river (nearly 250 miles), with tides of ex- traordinary height, and empties through one of the largest and richest coal-fields in Europe. It is navigable for a long distance, and is a great com- merce-carrier. The ilersey is a short river, rising on the Pennine slopes and obstructed at its mouth by a shifting bar, but its proximity to a rich coal-field and to the great manufacturing dis- trict of England gives it immense importance in commerce. The western rivers of Scotland, ex- cepting the Clyde, are only short, torrential, and commercially valueless streams; but the Clyde, artificially widened and deepened in its lower part at enormous expense, is the most important river in Scotland, and all the industries of the Low- lands and Southern Uplands — agricultural, min- eral, and manufacturing — are represented in its
