Page:Encyclopædia Britannica, Ninth Edition, v. 24.djvu/549

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WESTMOKLAND 515 vast pile of old marine sedimentary accumulations, ten or more thousand feet in total thickness, and mainly consisting of alterna tions of indurated shales, nmdstones, and Hags, with subordinate beds of grit. This is the Skiddaw Slate, which may be conveniently examined on and around Murton Pike, near Appleby. The same general type of strata prevails over a very wide area. The bottom of these "rocks has never been reached. The principal areas of inetamorpliie rocks in Westmorland are situated in the volcanic area. Rocks more or less altered by deep-seated action occur also around the Shap Granite. The alteration of the volcanic rocks here takes the form of an approach to the mineral characters of granite ; but there is no passage from the one to the other. The sedimentary rocks are altered also, more or less, but in a different way : the calcareous beds are developed into idocrase rocks, the cleavage in the Coniston Flags is sealed or welded up anew, while the grits are rendered more or less quartzitic. Amongst the plutonic rocks the chief is the well-known granitic porphyry, fragments of which occur in the Upper Old Red near Shap. There are many intrudes of diorite, gabbro, felsite, mica trap, and the like, all Post-Silurian and Pre- Carboniferous in age. Another well-known plutonic rock, of later date than the Carboniferous period, is the Whin Sill, an intrusive sheet of dolerite, which has eaten its way into the Carboniferous rocks over hundreds of square miles in the north of England. It forms the most characteristic feature of the sombre and gloomy fell-side recess known, as " High Cup Gill," or Haikable, near Appleby ; and it also forms the waterfall known as Caldron Snout. It is the newest intrusive rock known in Westmorland. The whole county is traversed in many directions by great numbers of faults. One set, the Pennine faults, call for a brief notice here. Two lines of disturbance continued northward from the Craven faults enter the county east of Kirkby Lousdale. One ranges north-north-eastwards, on the east of the Barbon Fells, and lets in the Carboniferous rocks forming Gragreth, throwing down about 2000 feet on the east ; it ranges by Dent, and east of Sedbergh, entering the county again in the valley between Clouds and the Ravenstonedale Fells. Here its effects are as strik ingly exhibited as at Gragreth, as the Millstone Grit summit of Wilbert Fell on one side of the fault is let down to the same level as the summits of the Silurian hills on the other. The second set of faults referred to throws down in the opposite direction, letting down the Millstone Grit, the Yoredalc Rocks, the Mountain Lime stone, and finally, as its throw diminishes, the Old Red, against the foot of the Silurian massif of the Barbon Fells. This fault ranges parallel to tho general course of the Lune nearly as far northward as Sedbergh, where it is joined by another set ranging east-north-east, which joins the set first described as ranging north-north-east to Ravenstonedale at a point near the county boundary north of Cautla. Thence the conjoined faults run northward in a very complex manner, producing some important effects upon the scenery about the foot of Mallerstang. Near Kirkby Stephen its throw changes from a downthrow to the east to one in the opposite direction, which throw increases rapidly in amount as the faults trend northwards, until at the foot of Stain- moor, below Barras, its throw amounts to quite 6000 feet down to tho west; and we find the important patch of Coal-Measures above noticed let down in consequence. At this point it changes in direction, running north-westerly, with many complications, past Brough, Helton, Dufton, and Milburn, out of tho county at the foot of Cross Fell. Along this line it throws down to the south west several thousands of feet ; and it is to the complicated disturb ances accompanying this great dislocation that nearly the whole of the more striking physical features of North Westmorland owe their origin. It is in connexion with the same important sets of disturbances also that the existence of most of the mineral veins of the district is due. Climate. The rainfall is exceptionally heavy. The largest quan tity recorded appears to be that in the mountains along the county boundary west of Grasmere, where the mean amounts to as much as 140 inches. At Sty Head the rainfall in 1872 amounted to 243 98 inches. The area of greatest rainfall forms a rude ellipsoid around these two places, lying with its longest dimensions towards the south-east, nearly coinciding with the distribution of land above 1500 feet. The heaviest precipitation takes place in the months of January, September, and October, and the smallest in July. At Grasmere, well in the heart of the mountains, but farther east, and at a much lower elevation, the mean rainfall for the past twenty years has been 80 inches, rain of 01 inch or more falling on about 210 days of the year. Between Grasmere and Shap the rainfall diminishes somewhat in the mountain areas. But in the lower ground still farther east the rainfall steadily but more rapidly diminishes, until at Milburn (644 feet) the mean for the last ten years has been about 33 inches on 175 days in the year. At Kendal the mean appears to be about 50 inches, and the number of wet days about 190 in the year; at Kirkby Lonsdale it is rather less, and at Kirkby Stephen less again. The mean tem perature for January is between 38 and 39 F., February 40-41, March 41-42, April 46-47, May 51, June 58 , July 60-61, August 60, September 56 U , October 49, November 42, and December 38-40. The principal characteristic of the climate is the preponderance of cloudy, wet, and cold days, especially in tho spring and the autumn, combining to retard the growth of vege tation. The late stay of cold winds in the spring has much to do with the same, especially in the lowlands extending along the foot of the Cross Fell escarpment from Brough north-westwards. Here, for weeks at a time, prevails a kind of cyclone revolving on a horizontal axis parallel to the escarpment, the " helm-wind." The remark able feature connected with it is that, when the wind is rushing furi ously from the slopes of the escarpment in the direction of the low grounds, little movement of the air can be detected on the summit. Flora and Fauna,. Among the denizens of the mountains are several plants distinctly alpine in character ; and others, more or less boreal in their principal stations, are here found at nearly their southernmost point of distribution. Bog plants are also conspicu ous in their variety, and include several forms of some rarity. Tho lichens, mosses, and ferns are well represented. Of trees the oak and the common elm do not seem quite at home anywhere except in the more sheltered nooks, and in parks and other cultivated places. But the place of the common elm is well supplied by the wych elm, which grows to great perfection. In place of the oak the sycamore is seen almost everywhere in the lower lands ; and there are probably few parts of England where the ash thrives so well, or attains to so large dimensions. On the higher lands, up to the upper limit of woodland growth, the birch, the hazel, and the mountain ash, and, in limestone districts especially, the yew are the prevailing trees. The alder is abundant, and willows of various kinds occur. The upland character of the region affects also its fauna. Tho badger, the polecat, and perhaps even the wild cat are still met with in Westmorland. The lineal descendants of the wild red deer range over a carefully-preserved remnant of the primeval forest in more than one place. The raven, the peregrine, and the buzzard may still be seen, and the moors sustain a considerable variety of birds other than grouse. The whistle of the golden plover and the note of the curlew are intimately associated with the scenery of the moory uplands. In the lowlands the avifauna is characterized rather by the absence of many forms common in the south than by the presence of birds elsewhere rare. The orni thologist cannot, however, help being struck with the comparative abundance of the redstart, the woodwren, and the grasshopper warbler, none of them very common in other parts of England. Minerals. Coal, the most important mineral product, occurs in connexion with the Carboniferous rocks, but most of the seams are thin and their quality is inferior, so that they have long ceased to have the industrial importance they once possessed. Fireclays of excellent quality and of unusual thickness occur with the coals at Argill, but have not hitherto been turned to indus trial account. Amongst the building-stones those of the New Red certainly deserve the first rank. The warm-tinted, easily- worked, and durable Penrith Sandstone furnishes one of the finest building-stones in the kingdom ; while the associated Brockrams are in their own way hardly less valuable ; and the same may lie said of the St Bees Sandstone, whence the materials used on so many of the larger public buildings of the northern part of the county have been derived. The Carboniferous rocks nearly everywhere furnish durable freestones and good flags. The Silurian rocks likewise yield building-stones, but somewhat difficult to work. Some of the thinner beds of Carboniferous sandstone are occasionally quarried for roofing purposes. The Coniston Flags are quarried at several places on the south side of the county ; while in the north-western parts cleaved beds of volcanic ash, belonging to the Borradale Series, have long furnished an ample supply of the well- known "green slates." Amongst stones available for ornamental purposes tho Shap granite-porphyry is undoubtedly the finest, as its choice for decorative purposes in our large cities has shown abundantly. In the way of marbles there are the bituminous limestones at tho base of the Yoredale Rocks, and the encrinital limestones nearer their top, both much appreciated ; while among limestones of different character there are the mottled and variegated limestones of several places in the neighbourhood of Kendal in the southern and of As by in the northern parts of the county. Well-chosen specimens of Brockram have a pleasing effect when polished. Gypsum is worked extensively in- the New Red rocks in the neighbourhood of Kirkby Thore and Temple Sowerby. Amongst the ores of the useful metals those of lead are of prime importance. The rich lodes of Greenside mines were until lately reckoned amongst the finest of their kind in the United Kingdom, and they have also supplied considerable quantities of silver, which has been extracted from the lead. These were worked in the volcanic rocks. Copper and zinc ores also occur in small quan tities. Haematite has been discovered here and there at many points, especially where calcareous strata have been affected by infiltration from the New Red rocks. 1 1 For other minei als of Westmorland, the interest of which is chiefly scientific,

see Trans. Cumb. and West. Assoc., Nos. 7, 8, and 9.