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THE LAND WE LIVE IN.

INTRODUCTORY CHAPTER.

ASTRONOMICAL AND GEOGRAPHICAL POSITION OF THE BRITISH ISLANDS.

THE BRITISH ARCHIPELAGO, consisting of Great Britain, Ireland, and numerous adjuncts, is situated between 49° 52′ and 60° 49′ N. lat. ; and between 1° 46′ E. and 10° 40′ W. long. The Channel Islands, which geographically belong to France, are not included in these limits; nor Rockall, a very small and solitary granite rock in the North Atlantic, upwards of 250 miles from the north coast of Ireland, and 180 miles from the most westerly of the Western Isles of Scotland, the nearest point of land. Herma Ness, in Unst, one of the Shetlands, forms the northern extremity, and the Scilly Islands the southern. Lowestoft Ness, on the coast of Suffolk, is the eastern confine, and the Blasquet Isles, off Dunmore Head in Kerry, the western. The archipelago lies off the north-west coast of Europe, from which it is separated by the North Sea or German Ocean, the Strait of Dover, and the English Channel. The opposite portions of the continent are the north of France, the Netherlands, Denmark, and the south of Norway.

Between the extreme eastern and western points, there is a difference of 12° 26' of longitude, or nearly 50 minutes of time; and owing to the range of latitude amounting to 10° 57', the sun is above the horizon at the summer solstice about 2 hours 40 minutes longer in the north than in the south. The length of the longest day, independent of refraction, is about 18 hours 48 minutes in the northern extremity, and 16 hours 8 minutes in the southern. This great length of the days at the summer solstice in the north, together with the nights consisting of brief intervals of bright twilight when the sky is cloudless, originated the impression current with the ancients that in the highest latitudes of the British Isles the sun did not set for 24 hours at midsummer. Pytheas of Marseilles, a Greek navigator, who visited Thule, supposed to be the Shetlands, probably in the fourth century before Christ, reported this physical exaggeration, which, nearly five centuries later, was reproduced in the pages of Tacitus: "In the farthest part of Britain," he states, "the nights are so clear that you can hardly tell when daylight begins or ends; and when the sky is not overcast with clouds, you may see all night long the light of the sun, which does not rise or go down, but moves quite round,”—a phenomenon only exhibited at and within the Arctic Circle.

Great Britain, the largest island of Europe, extends through 8° 43′ of latitude, from the parallel of the Lizard in Cornwall, 49° 57′, to that of Dunnet Head, 58° 40', the north extremity of Scotland; and through 7° 54′ of longitude, from the meridian of Lowestoft Ness, 1° 46′ E., to that of Ardnamurchan Point in Argyleshire, 6° 8′ W., which stretches somewhat farther west than the Land's End of England. It makes the nearest approach to the continent at the south-east angle, where the Kentish shore at Folkestone is not more than 20 miles from the French coast at Cape Grisnez, where the submarine telegraph station is now placed. The former union of the two countries by an isthmus, wasted by the denuding force of the seas on either hand, is intimated by the comparative shallowness of the intervening strait, the proximity, and identity in composition, of the opposite cliffs and shores, whether flat

B.-VOL. I.

and sandy, or steep and chalky, and the occurrence of a submarine ridge running across the Channel. Northwards, from this point of contiguity, the British coast has a general direction N.W., and the continental N.E., the two therefore mutually receding, a distance of 400 miles subsisting between Scotland and Denmark. In the contrary direction, the British coast trends W. by S., and the continental S.W., consequently retreating from each other, but in a less degree than in the preceding instance, their greatest distance being about 140 miles, from St. Alban's head, in Dorsetshire, to St. Malo, in Brittany.

Ireland, to the west of Great Britain, is separated from it by the Irish Sea, St. George's and the North Channels. It comprises nearly 4° of latitude, from Brow Head in Cork to Malin Head in Donegal; and 5° of longitude, from the east of County Down to Cape Sybil in Kerry. The north extremity corresponds in latitude to that of the Coquet River at its mouth in Northumberland, and the south point to that of Bristol. It approaches nearest to Great Britain in the north-east, where Fair Head in Antrim is only 13 miles from the Mull of Cantire in Argyleshire. In the south-east, the distance is about 50 miles between the nearest projections, Greenore Point in Wexford, and St. David's Head in Wales.

The smaller portions of the archipelago are very unequally distributed. They are prolongations of the western and northern extremities of the two main masses, excepting the Isle of Wight, off the south coast of England, and a few islets of unimportant extent. The Scilly group, 140 in number, including mere rocks, is evidently a detached extension of the south-west angular projection of England. Anglesea and Holyhead are close adjuncts of the mainland of Wales. The Isle of Man, by its configuration and the direction of its high land, from N.E. to S.W., indicates itself to be a continuation of the adjacent Scottish coast. The Isles of the Firth of Clyde and the Inner Hebrides, are prolongations of the western mainland of Scotland, of which the Outer Hebrides form a more distant detachment; the Flannan Islands, with St. Kilda, being remote outliers of the latter group. The three clusters comprise upwards of 200 members, of which about 80 only are inhabited. Northwards the main mass of Britain is prolongated by the Orkneys, 67 in number, with 29 inhabited; and by the more outlying Shetlands, consisting of upwards of 100, with 32 inhabited. The islands connected with Ireland are principally western or north and south-western prolongations of the mainland, in most instances very little detached, amounting to nearly 200, of which between 130 and 140 are inhabited.

No straight line can be drawn due north and south intersecting the whole of Great Britain, owing to its general inclination N.W. The meridian of 2° W., which cuts the centre of England from the Dorset coast to Berwick upon Tweed, scarcely touches Scotland at all. The greatest direct linear extent of the surface is from S.E. to N.W., stretching from Rye in Sussex to Cape Wrath in Sutherlandshire, measuring about 580 miles; and the next longest straight line, cutting no portion of the sea, extends from S.W. to N.E., or from the Land's End to Winterton Ness on the Norfolk coast, including 367 miles. Due east and west, the greatest breadth occurs near the parallel of 52°, between St. David's Head in Pembrokeshire and the Naze in Essex, the distance being about 280 miles. But the deep indentations of the sea remarkably contract the space between the opposite coasts at various points, and almost insulates the north extremity of Scotland.

The North Sea, forming a kind of Mediterranean or close sea between the east of Great Britain and the Continent, extends from the Strait of Dover, lat. 51° N., to a line which joins the northernmost of the Shetlands with the coast of Norway at the Sogne Fiord, near lat. 61° N. From south to north it comprises a linear extent of 690 miles, by 405 miles from east to west, where the greatest expansion occurs, about the parallel of 56°, between St. Abb's Head on the Berwickshire coast, and the Ringkiobing Fiord on the Danish shore. Its area is computed at 244,000 square miles. The greatest depth is on the Norwegian side, where the soundings give from 100 to 290 fathoms; but the mean depth of the whole is stated by Mr. Stevenson to be only about 31 fathoms. Notwithstanding the irregularity of the depth from the occurrence of numerous sandbanks, it increases upon the whole as we proceed from south to north. Transverse sections, taken at various points, show that from west to east the depth varies considerably; but that, as a general conclusion, there is a greater depth of water on the west and east sides except close in shore, than in the central parts; and that on the whole the water is deeper on the British than on the continental shores, the coast of Norway excepted. Great accumulations of debris occupy the bed of the sea. The Dogger Bank, which is subdivided by the navigator into the Long Bank, the White Bank, and the Well Bank, occurs in the centre, extending upwards of 300 miles from north to south. Another great bank, known to mariners as the Long Forties, stretches upwards of 110 miles N.E. from the mouth of the Firth of Forth. A considerable

number, of inferior dimensions, lie between the entrance of the Humber and the South Foreland, among which the Goodwin Sands have acquired an unhappy notoriety for the numerous shipwrecks of which they have been the scene. These sands, about 10 miles long, by from 3 to 4 broad, divided into two parts by a narrow channel navigable for small boats, lie off the Kentish shore between the North and South Foreland, and form a kind of breakwater, protecting on the east the roadstead of the Downs. Altogether, from a vast number of observations and comparisons, Mr. Stevenson estimates the average height of the sandbanks of the North Sea at about 78 feet, their superficial extent at upwards of 27,400 square miles, and their solid contents at no less than 2,241,248,563,110 cubic yards, -equal to 28 feet of the whole of Great Britain in perpendicular height or depth, supposing its surface to be a level plane.

The British part of the coast-line is marked with several considerable inlets,-the estuaries of the Thames, the rivers of the Wash and the Humber, with the Firths of Forth, Tay, Murray, and Dornoch. It presents also prominent projections, the most extensive being the angular district terminating at Kinnaird's Head in Scotland, and the rounded protuberance formed by the most easterly counties of England. But generally the coast is far more regular than on the west of the island. South of Flamborough Head the shores have for the most part a tame appearance, consisting of low cliffs of clay or chalk, flat marshy lands, and sand-hills or sandy levels; but northwards from that promontory a bold and rocky character predominates.

The English Channel, separating Great Britain and France, extends from the Strait of Dover to a line connecting the Land's End and the Island of Ushant, a distance somewhat exceeding 300 miles. Westward from the narrow strait, the Channel rapidly expands to 90 miles from Brighton to Havre, contracting to scarcely 70 between St. Catherine's Point on the Isle of Wight and Cape Harfleur, but opening to upwards of 110 miles at its junction with the Atlantic.

The Irish Sea, with St. George's and the North Channels, between Great Britain and Ireland, extends from a line joining Carnsore Point with St. David's Head on the south, to a line connecting Fair Head with the Mull of Cantire on the north, and includes an area estimated at 22,900 square miles. Its bed on the side of Ireland is largely encumbered with shifting sands, bars, and sunk rocks; and sandbanks render the navigation intricate on the British side towards the estuary of the Mersey. The two coast-lines differ remarkably. Few inlets of importance occur on the Irish shore, while the opposite shore of Wales has the deep indentation of Cardigan Bay, and the most extensive inlet of the sea exhibited in the British Islands is formed between North Wales and South Scotland.

The Atlantic, from the south-west of England, round the greater part of Ireland, and the west and north of Scotland, to the Shetlands, supplies a magnificent seaboard, the rugged and torn aspect of the shores exposed to its huge breakers proclaiming their force. The coasts are generally bold, rocky, and precipitous, largely consisting of long narrow peninsulas, formed by the denuding action of the waves upon the more yielding materials. A remarkable physical feature of the Atlantic in the neighbourhood of the British archipelago is the sudden and great depression of its bed from 100 to 200 fathoms and upwards, indicated by dotted lines upon the map

MOUNTAIN SYSTEMS OF THE BRITISH ISLANDS.

SOUTH BRITAIN, according to the aspect of the surface, may be considered as consisting of two principal divisions, possessing a definite and distinct physiognomy, a generally rugged and occasionally mountainous tract on the north-west, west, and south-west; and a district of gentle elevations intermingled with plains, much more extensive, embracing the eastern, central, and southern counties. They may be conveniently styled Highland and Lowland Regions.

The Highland Region extends, though with several interruptions, along the western side from the Scottish border to the Land's End, approaching the east coast in the north, and running out towards the centre of the kingdom in the hills of Derbyshire and Staffordshire. It comprises the Pennine Chain, the Cumbrian, Cambrian, and Devonian or South-western Mountain Systems, with detached ridges and eminences.

PENNINE CHAIN.-This Chain traverses northern England in the line of its length from north to south. It stretches from Carter Fell, one of the Cheviots, near the sources of the Upper Tyne on the frontier of Scotland, lat. 55° 18′ N., to the Weaver Hills on the east border of Staffordshire, lat 52° 50′ N., comprising an entire course of about 170 miles. A depression intersected by the Newcastle and Carlisle Railway, near to which is the line of the old Roman wall, and the valleys in which the Eden, Tees, Lune, Ribble, and affluents of the Yorkshire Ouse, have their upper courses, interrupt its continuity. The chain, low and narrow at its north extremity, attains its greatest elevation near the

junction of Cumberland, Westmoreland, and Durham, acquires considerable expansion in Yorkshire, and continues broad and high to the Derbyshire Peak. Mountain limestone, largely cavernous, is the characteristic rock, composing the great masses of Cross Fell, Ingleborough, Wharnside, and Pennigant. Millstone grit, extensively developed, forms the surface of elevated moorlands covered with heathy vegetation, and is occasionally seen capping isolated limestone summits, projecting in remarkably bold escarpments.

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PROJECTION OF MILLSTONE GRIT, ON THE TOP OF STONNIS, DERBYSHIRE.

In the East Riding of Yorkshire there is an extensive tract of high lands completely detached from the offsets of the Pennine Chain by the valley of the Ouse and its tributaries. It is divided into two principal portions by the valley of the Derwent, extending east and west, the northern portion forming the Egton or North York Moors, and the southern the Yorkshire Wolds. The former district has a general elevation of 1000 feet, but rises in Black Hambleton Down to 1246 feet; Loosehoe Hill, 1404 feet; and Button Head, 1485 feet. The Wolds are considerably lower, Wilton Beacon, 12 miles E. by N. from York, the highest point, being only 809 feet.

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CUMBRIAN SYSTEM.-This group forms, with the preceding chain, a continuous mass of high land, but its geological constitution is quite distinct; and while its direction is nearly at a right angle with that of the Pennine Range, it acquires a character superior to that of a lateral offset by its great elevation. The two, therefore, though frequently classed together under the denomination of the Northern Range of England, are more properly separated. The narrow valley through which the

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Eden descends from its source to Kirkby Stephen, in lat. 54° 25', about the parallel of Richmond, Yorkshire, may be regarded as the eastern limit of the Cumbrian or Lake Mountains, which extend from thence, variously expanding, nearly due west towards the Irish Sea, terminating at Dent Hill near Egremont, a few miles from the coast. They stretch from east to west about 35 miles, by 37 miles from north to south, where the group has its greatest expansion, and are estimated to occupy more than a third of Cumberland, about a fifth of Westmoreland, and a small part of north Lancashire. Varieties of slate constitute the main masses, intersected by dykes of trap, and associated with granite, sienite, greenstone, and other primitive rocks.

The Cumbrian Group and Pennine Chain inclose the extensive plain of North Cumberland, near the centre of which is Carlisle. The tide sometimes ascends the Eden to within four miles of the city; the water is salt to within five miles of it; and the coast is so low above Maryport that a very slight rise of the sea would send its waters to the foot of the mountains, and change the Solway Firth into a great gulf.

CAMBRIAN SYSTEM.-Wales, the most truly Alpine district of South Britain, has almost its whole surface occupied by ranges of mountains, which, while really distinct, have such a close general connection as properly to be classed together in one group; and the ridges and heights of the English counties bordering on the principality, may be viewed as detached offsets of the Cambrian System. The principal chains are Snowdonia, the loftiest, in the north-west, chiefly occupying Caernarvonshire ; the Berwyn range, extending from near the mouth of the Dovey in Cardigan Bay N.W. to the junction of the three counties of Denbigh, Salop, and Cheshire; the Plynlimmon range, stretching from the mountain of that name along the south side of the valley of the Upper Severn into Salop; and the range of South Wales, running nearly due east and west between the Usk and Towy rivers, parts of which are styled the Black Mountains, from the dark appearance of the heather when out of blossom. These chains have many offsets, and high moorland tracts occur apart from them. Coal strata occupy an extensive area in South Wales; the mountain limestone appears in the north-east; the old red sandstone occurs in force in the south-east and south; but slates and sandstones of the Silurian series are the characteristic formations, associated to some extent with porphyritic and other trappean rocks. The hills of south Salop, and the Malvern Hills, which divide Herefordshire from Worcestershire, are outlying portions of the mountain system of Wales. The Malverns form a beautiful ridge, extending about eight miles, but everywhere narrow, swelling into many distinct summits, principally composed of sienite.

The mountains of Wales are not continuous with those of the north of England, but separated by an extensive plain which comprehends the south-west of Lancashire, great part of Cheshire, and north Salop. They are divided also from the next group by the valley of the Severn and its estuary.

DEVONIAN OR SOUTH-WESTERN SYSTEM.-The angular projection of England terminating at the Land's End, only assumes a mountainous character at a few points, and contains no extensive definite chain, but rather consists of a series of bleak rugged heights stretching through Cornwall, connecting themselves with the grand plateau of Dartmoor in South Devon, and with the elevated mass of Exmoor in the north, which stretches into Somersetshire, prolonged by the Quantock Hills towards Bridgewater. The Black Down Hills, Mendips, and other ridges of the latter county, may be regarded as offsets; and the Cotteswold Hills of Gloucestershire as a detached outlier. Granite, with transition rocks consisting of varieties of slates, constitute the masses of Devon and Cornwall. The Black Down Hills are composed of green sand. Old red sandstone forms the nucleus and highest points of the Mendips, the mountain limestone clothing the flanks. The Cotteswold Hills are oolitic.

A further portion of the southern counties belongs to the South British highlands, near the junction of Wilts, Hants, and Berks, where the Inkpen Beacon attains the elevation of 1011 feet, the highest point of the chalk in Great Britain.

The remainder of the surface, from the Vale of York to the English Channel, and from the North Sea to the Welsh border, is composed, with a few exceptions, of formations more recent than the carboniferous epoch,-the new red sandstone, oolitic, wealden, and cretaceous groups, with tertiary deposits, which nowhere attain the height of a thousand feet. But an agreeable diversity marks its general aspect. The leading features consist of broad and fertile river-valleys, verdant hills, ranges of downs occasionally, bold, barren, and heathy, and a large extent of comparatively level country forming the great south-eastern plain of England, comprising some marshy grounds. From Salisbury Plain, a woodless tract of table-land with an uneven billowy surface, three ridges of chalk hills diverge E. by S., E., and N.E., cut up into separate masses by transverse river-valleys, presenting rounded summits with one side steeper than the other, a characteristic of the chalk. The most southern range crosses

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