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 not generally remarkable for great beauty of outline. The higher parts are bleak and wild, and the slope towards the central plain is gradual. The chief beauty of the district is to be found in the numerous deeply scored valleys or dales, such as Teesdale, Swaledale, (q.v.), Nidderdale, Wharfedale and Airedale, in which the course of the streams is often broken by waterfalls, such as High Force in Teesdale and Aysgarth Force in Wensleydale.

The hills E. of the central plain cannot be similarly considered as a unit. In the N., wholly within the N. Riding, a line of heights known as the Cleveland Hills, forming a spur of the N. Yorkshire Moors, ranges from 1000 to nearly 1500 ft., and overlooks rather abruptly the lowest part of the Tees valley. The line of greatest elevation approaches the central plain, and swings sharply S. in the Hambleton Hills to overlook it, while to the S. of the line long deep dales carry tributary streams S. to the river Derwent, thus draining to the Ouse. Eastward the N. Yorkshire moors give immediately upon the coast. Their higher parts consist of open moorland. The remarkable upper valley of the (q.v.) marks off the N. Yorkshire moors from the Yorkshire wolds of the E. Riding, the river forming the boundary between the N. and E. Ridings. The wolds superficially resemble the moors, inasmuch as they abut directly on the coast E., run thence W., and swing S. to overlook the central plain. At the S. extremity they sink to the shore of the Humber. Their greatest elevation is found near the W. angle (Howardian Hills), but hardly reaches 800 ft. Eastward they encircle a low-lying fertile tract bounded S. by the Humber and E. by the North Sea. The name of Holderness is broadly applied to this low tract, though the wapentake of that name includes properly only the E. of it.

The diverse character of the coast may be inferred from the foregoing description. In the north, S. of Teesmouth, it is low for a short distance, then the E. abutments of the Cleveland Hills form fine cliffs, reaching at Boulby the highest elevation of sea cliffs in England (666 ft.). Picturesque valleys bearing short streams break the line, notably that of the Esk, reaching the sea at Whitby. The trend of the coast is at first S.E. and then S. South of Scarborough it sinks with the near approach of the Derwent valley, begins to rise again round the shallow sweep of Filey Bay, and then springs seaward in the fine promontory of Flamborough Head (see ). South of this, after the sharp incurve of Bridlington Bay, the low coast-line of Holderness succeeds, long and unbroken, as far as Spurn Point, which encloses the mouth of the Humber. Encroachments of the sea are frequent, but much land has been reclaimed.

There are several watering-places on the coast in high favour with visitors from the manufacturing districts. The principal, from N. to S. are Redcar, Saltburn-by-the-Sea, Whitby, Robin Hood's Bay, Scarborough (the largest of all), Filey, Bridlington and Hornsea. There are numerous mineral springs in Yorkshire, the principal being those at Harrogate. There is also a spa at Scarborough, and others are Askern near Doncaster, Boston Spa near Harrogate, Croft on the Tees near Darlington, Hovingham, near Malton, Guisbrough in Cleveland and Slaithwaite near Huddersfield. The springs are chiefly sulphurous and chalybeate.

By far the greater part of Yorkshire is within the drainage basin of the Ouse, which with the Trent makes the estuary of the (q.v.). It is formed in the central plain by the junction of the Ure and Swale, both rising in the Pennine hills; but whereas the Swale drains the N. of the plain, the Ure, traversing Wensleydale, is enclosed by the hills over the greater part of its course. The Ouse also receives from the Pennine district the Nidd, traversing Nidderdale, the Wharfe, the Aire, with its tributary the Calder, and the Don. The Aire rises in the fine gorge of Malham Cove, from the subterranean waterways in the limestone. None of these tributaries is naturally navigable, but the Aire, Calder and Don are in part canalized. From the E. the principal tributary is the Derwent, which on entering the central plain follows a course roughly parallel to that of the Ouse, and joins it in its lower part, between Selby and Howden. The Foss joins the Ouse at York. In the W. the county contains the headwaters of several streams of the W. slope of the Pennines, draining to the Irish Sea; of these the principal is the Ribble. In the N. the Tees forms most of the boundary with the county of Durham, but receives no large tributary from Yorkshire. In the S. of the W. Riding a few streams drain to the Trent. In Holderness, debarred by the wolds from the general drainage system of the county, the chief stream is the Hull. The only sheets of water of any size are Semmer Water, in a branch of Wensleydale; Malham Tarn, near the head of Airedale, the effluent of which quickly disappears into an underground channel; and Hornsea Mere, near the flat seacoast at Hornsea.

Geology.—The great variety in the scenery of Yorkshire is but a reflection of the marked differences in the geological substructure. The stratification is for the most part regular, but owing to a great line of dislocation nearly coincident with the W. boundary of the county the rocks dip towards the E., while the strike of the strata is from N. to S. The bold and picturesque scenery of the western hills and dales is due to the effects of denudation among the harder rocks, which here come to the surface. The strata in the Pennines consist of (1) older Palaeozoic rocks, viz. a faulted inlier of Silurian and Ordovician at Horton in Ribblesdale, and a small patch of Silurian at Sedbergh with inliers of Coniston limestone; (2) the Carboniferous or Mountain Limestone, which has been subjected to great dislocations, the more important of which are known as the N. and S. Craven faults; (3) the Yoredale series, consisting of shales, flagstones, limestones and thin scams of coal; and (4) the Millstone Grit, forming part of the hilly moorlands, and capping many of the loftier eminences. In the W. Riding the Pennine range forms part of the elevated country of Craven and Dent. The scenery in the W. of the N. Riding is somewhat similar to that in Craven, except that the lower hills are of sharper outline owing to the perpendicular limestone scars. To the intermingling of the limestone with the softer rocks are due the numerous “forces” or waterfalls, which are one of the special features of the scenery of this district. The action of water on the limestone rocks assisted by joints and faults has given rise to extensive caverns, of which the best examples are those of Clapham and Ingleton in the W. Riding, as well as to subterranean watercourses. At Brimham, Plumpton and elsewhere there are fantastic masses of rocks due to irregular weathering of the Millstone Grit. The Pennine region is bounded on the S.E. by the Coal Measures, forming the N. of the Derbyshire, Nottingham and Yorkshire coal-field, which in Yorkshire extends from Sheffield N. to Leeds. The noted fire clays of the Leeds district are obtained from this formation. To the E. the Coal Measures dip beneath the unconformable Permian beds, with magnesian limestone and marl slate, of which a narrow band crops up from Masham southwards. The Permian strata are overlain to the E. by the Trias or New Red Sandstone, scarcely ever exposed, but having been partly worn away is covered with Glacial deposits of clay and gravel, forming the low-lying Vale of York, extending from the Tees S. to Tadcaster and E. beyond York to Market Weighton. Near Middlesbrough red rock with gypsum and rock-salt (100 ft.) have been proved. Farther E. the Triassic beds are overlain by Lias and Oolite, Rhaetic beds have been recorded from near Northallerton. The Lias crops to the surface in a curve extending from Redcar to the Humber. In the Middle Lias there is a seam of valuable iron ore, the source of the prosperity of the Cleveland region. The moorlands extending from Scarborough and Whitby are formed of Liassic strata, topped with the estuarine beds of Lower Oolite, rising gradually to the N.E. and attaining at Burton Head a height of 1489 ft., the greatest elevation of the Oolite formation in England. In the Oolitic “Dogger” series the magnetic iron ore of Rosedale is worked. Corallian rocks form the scarp of the Hambleton hills and extend E. on the N. of the Vale of Pickering through Hackness to the coast, and S.W. of the vale to the neighbourhood of Malton. The Vale of Pickering is underlaid by faulted Kimeridge Clay. Lias and Oolites fringe the E. of the Vale of York to Ferriby on the Humber. In the S.E. of the county, Cretaceous rocks cover up the older strata, N. to the Vale of Pickering and W. to the Vale of York. The Chalk forms the Yorkshire wolds and the country S. through, Driffield, Beverley and Holderness.

The Yorkshire coast between Redcar and Flamborough presents a continuous series of magnificent exposures of the strata from the Lower Lias to the Chalk. The Upper Lias fossils and jet of Whitby and alum shale of Saltwick are well known. At Scarborough the Corallian, Oxford Clay, Kellaways Rock, Cornbrash and Upper Estuarine beds are well exposed in the cliffs. In Filey Bay the Kimeridge Clay appears on the coast, but it is covered farther S. by the historic beds of Speeton, representing the marine equivalents of Portland, Purbeck, Wealden, and Lower Greensand of S. England. Over the Speeton beds lies the Red Chalk, the Yorkshire equivalent of the Upper Greensand and Gault. The evidences of glacial action are of unusual interest and variety; the great thickness of boulder clay on the coast is familiar to all, but inland also great deposits of glacial clay, sand and gravel obscure the older geology. The Vale of Pickering and many of the smaller northern valleys were at one period the sites of Glacial lakes, and the “warp” which covers much of the Vale of York is a fluvio-glacial deposit. The Cleveland Dike is an intrusive igneous dike of augite-andesite of Tertiary age which can be traced across the country in a N.W. direction from the neighbourhood of Fylingdales Moor.

Minerals.—The coal-field in the W. Riding is one of the chief sources of mineral wealth in Yorkshire, the most valuable seams being the Silkstone, which is bituminous and of the highest reputation as a house coal, and the Barnsley Thick Coal, the great seam of the Yorkshire coal-field, which is of special value, on account of its semi-anthracitic quality, for use in iron-smelting and in engine furnaces. Associated with the Upper Coal Measures there is a valuable iron ore, occurring in the form of nodules. Large quantities of fireclay are also raised, as well as of gannister and oil-shale. Middlesbrough is the most important centre of pig-iron manufacture in the kingdom. Lead ore is obtained in the Yoredale beds of the Pennine range in Wharfedale, Airedale, Nidderdale, Swaledale, Arkendale and Wensleydale. Slates and flagstones are quarried in the Yoredale rocks. In the Millstone Grit there are several beds of good building stone, but that most largely quarried is the magnesian limestone of the Permian series, which, however, has of somewhat variable quality.