YORKSHIRE, a north-eastern county of England, bounded by Durham, the North sea, the Humber estuary (separating it from Lincolnshire), Nottinghamshire, Derbyshire, Cheshire, Lancashire and Westmorland. It is the largest county in England, having an area of 6,046.3 sq.m. (exclusive of water) and being more than double the size of Lincolnshire, which ranks next to it. In a description of the county it is constantly necessary to refer to its three great divisions, the North Riding, East Riding and West Riding.
Physical Features.—The county of Yorkshire can be divided into four upland tracts separated by lowland areas. These lie in the south-west, north-west, north-east and south-east quadrants of the county respectively. The great Yorkshire plain, drained by the Yorkshire Ouse (q.v.), stretches from the river Tees, which forms the northern boundary of the county, through the Vale of Mowbray, Vale of York and Vale of Ouse to the Trent basin in the south. The Ouse divides the county into an eastern and a western division; whilst the "Aire Gap" separates the north Pen nine moors from the south Pennine moors, and on the eastern side the Vale of Pickering separates the north Yorkshire moors from the Yorkshire Wolds. The north Pennine moors, which stretch northwards beyond the limits of the county, form a high moorland tract of Carboniferous limestone and Yoredale beds capped by millstone grit. The rocks have a very small dip east ward but are fractured by a series of faults, the most important being the Craven faults from Kirkby Lonsdale by Ingleton, Stainforth and Linton. There are also inliers of Ordovician and Silurian rocks at Horton and at Sedbergh.
The chief valleys are Teesdale, Swaledale, Wensleydale, Nidder dale, Wharfedale and Airedale. The chief peaks are Mickle Fell (2,591 ft.), Whernside (2,414 ft.), Ingleborough (2,373 ft.), Buckden Pike (2,302 ft.) and Penyghent (2,273 ft.). The "Aire Gap," which forms the gateway between north Lancashire and Yorkshire, has been followed by roads, railways and canals. The south Pennine moors are formed of millstone grit, which has been arched upwards approximately along the county boundary and the coal measures are preserved along the eastern and western flanks. The uplands are bleak grouse moors in which the feeders of the rivers Aire, Calder and Don, have carved out valleys across the northern portion of the Yorkshire, Derby and Notts coal field. Between the Yorkshire plain and the Pennines there is a belt
of magnesian limestone, which, lying across various members of the Carboniferous, forms a well marked scarp-face toward them in the southern half of the county. The country along this belt forms a marked contrast with the districts of Palaeozoic rocks on the west, for the limestone produces a rich soil, the effect of which is seen in a luxuriant vegetation.
On the south the alluvium-filled Vale of Pickering marks the site of an ancient lake and the river Derwent, which drains the vale, has broken its way through the Jurassic ridge of the Howardian hills to reach the Vale of York. In this south-eastern quadrant the chalk forms the Yorkshire Wolds and has a general dip towards the south-east thus forming scarp edges from Flam borough Head, along the south side of the Vale of Pickering and sweeping round in a broad arc toward Market Weighton. This ridge of higher ground is continued southward across the Humber into the Lincolnshire Wolds. The north Yorkshire moors rise immediately from the coast and form cliffs for the most part, whilst to the south of Flamborough Head the cliffs disappear beneath the low-lying drift-covered Holderness. There are several watering-places along the coast; the principal are Redcar, Salt burn-by-the-Sea, Whitby, Robin Hood's bay, Scarborough, Filey, Bridlington and Hornsea. There are numerous mineral springs in Yorkshire, the principal being at Harrogate.
Minerals.—The coal-field in the West 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 iron-smelting and engine furnaces. Associated with the upper coal measures are iron-ores, occurring in the form of nodules. Brick-clay, pottery clay and fire-clay are also raised, as well as gannister and oil shale. Middlesbrough is the most important centre of pig-iron manufacture in the kingdom. Lead-ore occurs in the Yoredale beds of the north Pennine moors, 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.