Page:Encyclopædia Britannica, Ninth Edition, v. 6.djvu/733

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COUNTY.] CUMBERLAND 697 woodlands, which, combined or contrasted with the gigantic masses around them, exhibit many remarkable scenes of grandeur, desolation, and beauty. Scawfell, Skiddaw, and Helvellyn, rising to the height of more than 3000 feet, belong to this quarter. The highest part of that immense ridge known as the Pennine chain, and not inaptly termed the " backbone " of England, which, rising in Derbyshire, extends in a continuous chain into the Lothians of Scotland, forms the eastern boundary; the culminating point of this ridge is Crossfell, nearly 3000 feet high; it is surrounded with other lofty and bleak eminences, which retain the snow upon them for more than half the year. The following are the loftiest heights, with their respec tive elevations : Feet. Scawfell Pike 3210 Scawfell 3162 Helvellyn 3118 Skiddaw 3058 Great End... ....2984 Feet. Bowfell 2960 Great Gable 2949 Pillar 2927 Blencathra 2847 Grisdale Pike 2593 The north and north-eastern part of the county consists of the vale of the Eden, which separates the Pennine chain from the mountainous system of the south-west, and gradually expands into the great Cumbrian plain, extend ing north and north-west to the shores of the Solway. A tract of low land, varying from two to five miles in breadth, and consisting generally of a gravelly or sandy soil, extends along the coast-line. [Geology.- The oldest rocks known in this county a^e the Skiddaw slates, representing ancient marine deposits of clay and sand formed during a long period of subsidence and containing a fev fossils (graptolites, trilobites, phyllopod Crustacea, <fec.). These old mud rocks have been much contorted, cleaved, and metamorphosed, the metamorphosed portions, including chiastolite slate, spotted schist, and mica schist (rarely gneissic), being specially developed around the granite of Skiddaw Forest. The quiet marine condi tions under which these slates were formed seem to have given way to a long series of volcanic outbursts, at first sub-marine in character, but soon becoming sub-aerial. Thus, above the Skiddaw slates are piled up great thicknesses of volcanic ashes and lavas the volcanic series of Borrowdale (or greeu slates and porphyries). Then must have followed a renewed period of depression beneath the waters of the sea, and upon the denuded sur face of volcanic rocks the great series of sedimentary strata known as the Coniston limestone and the overlying Upper Silurian (Westmoreland, about Windermere and Kendal) was deposited. The next geological epoch (the Devonian or Old Pied) is unrepresented in Cumberland by any sedimentary deposi tion, except quite tow r ards it close; but during the long lapse of time between the Upper Silurian and the commencement of the Carboniferous, that mighty but pro bably slow elevation and denudation of all the previously formed rock-groups took place, which resulted in the first appearance of the Cumberland mountain district, the rough- hewn block out of which, during long succeeding ages, mountain and valley were carved. Around this early nucleus was formed the conglomerate so well shown in Mell Fell and at the foot of Ullswater. and then the thick series of Carboniferous rocks, the limestones, sandstones, shales, and coal-seams, which form so admirable a framework to the mountain country. In Carboniferous times there must have been frequent alternations of marine and low-lying land conditions over large parts of Cumberland. At the close of this period the conditions around the mountain nucleus, whether marine or partly fresh-water, allowed of the deposition of great thicknesses of sandstones (mostly red) and marls, together with some breccias and magnesian limestone, which make up the geological formations known as the Permian and New Red (or Trias). With the exception of a small area occupied by Liassic rocks, near Carlisle, no newer formations are known in Cumberland; but during that great length of time represented by the Secondary and Tertiary rocks of the rest of England, the area which is now our lake district seems to have been dry land, and to have been sculptured and moulded by atmospheric denudation into its present form. Within comparatively recent times this district has been the home of glaciers, which have left abundant traces of their former existence in the ice-scratched and rounded rocks, perched blocks, and glacial moraines. Besides these various rock-groups, there are several large masses of granite and granitoid rocks in the area of the mountain district. Granite occurs in Skiddaw Forest and in Eskdale. Syenitic and quartz-felsitic rocks occur in Buttermere and Ennerdale (closely associated with the Eskdale granite), in St John s Vale, and in other smaller masses. Bosses and dykes of diorite and dolerite are of frequent occurrence among the older Silurian rocks, but the basalt known as the Whin Sill is the only instance of intrusive igneous rocks yet recognized among the post- Silurian strata. The mineral resources are extensive. Among the Lower Silurian rocks (Skiddaw slates and volcanic series) are veins of iron (but little worked), lead, and copper, while the cele brated plumbago mine occurs in the midst of some intrusive dioritic and diabasic masses among the volcanic rocks of Borrowdale. The valuable deposits of hematite are found in connection with the Carboniferous limestone, and the Whitehavea coal-field furnishes a large supply of valuable fuel. Lead veins of much value occur in the limestone area in the east of the county, and specially in the neigh bourhood of Alston. Slates are worked in the volcanic series, in which case they consist of cleaved ash-beds, and flags are largely wrought among the Coniston ssries in the Upper Silurian. Building stone of more or less value is found in the various formations developed in the county. (j. c. WA.)] The climate necessarily corresponds with the variety of surface. Along the shore-level it is mild and temperate, though subject to an excess of moisture compared with the eastern part of the country; among the mountains the winters are sometimes very rigorous, but more frequently subject to heavy and almost incessant rain for days at a time. The average yearly rainfall, as shown by careful observation for several years back, is as follows : Carlisle, 30 inches; Wigton, 34; Whitehaven, 50; Keswick, 59; while at Seathwaite, in Borrowdale, 420 feet above the sea- level, it amounts to about 140 cubic inches. On the Sty- Head Pass, at an elevation of 1077 feet, the rain-guage showed in the year 1872 the enormous fall of 243 98 cubic inches, which, as far as has yet been ascertained, marks this region as the wettest spot in Europe. Black peaty earth is the most prevalent soil in the mountainous districts, and is found, too, in the moors and commons of the eastern parts of the county. About one-half the cultivated land consists of dry loams, excellently adapted for the growth of turnips, potatoes, grain, and herbage. Fertile clays occupy only a small portion, but clay, wet and sterile, forms the subsoil in many parts. The principal rivers are the Eden, Irthing, Derwent, Greta, Caldew, and Esk. The Eden has its source in Westmoreland, near the borders of Yorkshire, and, pursuing a north-westerly direction through Cumber land, passes Kirkoswald and Carlisle, falling into the Solway Firth near Rockliffe Marsh, where it forms a fine estuary. The land on its banks is for the most part very narrow, and in some places the high grounds approach to the water s edge. On this river there are several valuable

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