Page:Encyclopædia Britannica, Ninth Edition, v. 24.djvu/280

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256 VIRGINIA Maryland, and on the E. by the Virginian Sea of the Atlantic Ocean. Its greatest length from east to west is 476 miles, its greatest breadth from north to south 192 miles. It is subdivided into 100 counties. The area is variously stated at about 44,500 and 42,450 square miles ; the latter extent is that given at the census of 1880. Of the 1,512,565 inhabitants of Virginia (1,059,034 of them over ten years of age) in 1880, 494,240 were engaged in gainful occupations, 254,099, or over 50 per cent., in agriculture, 30,418 in trade and transportation, and 63,059 in manufactures and mining and mechanical industries; but now (in 1888) a very much larger proportion of the industrial population is engaged in mining, manufacturing, trade, and transportation, in consequence of the opening of mines, the erection of blast-furnaces, coke ovens, and various manufacturing establishments since 1880. Physical Physical Features. Speaking broadly, Virginia may be features, divided into a lowland and a highland country. Its south-eastern part over 23,000 square miles, or more than half of the whole has the aspect of a broadly undulating plain, that, with but few marked variations of relief, rises from the sea-level to from 400 to 800 feet above it. The north-western portion is a region composed of approximately parallel mountain ranges, running entirely across the State from north-east to south-west, separated by nearly parallel valleys, the whole presenting all the varieties of relief peculiar to the Appalachian country between the levels of 800 and 5700 feet. To speak more accurately, the State is naturally divided into seven grand divisions or belts, each with marked characteristics of relief and geological structure, and each succeeding the other, somewhat as a more or less ascending stairway, from the sea to the north-west. 1 . Tidewater Virginia is the marine plain, of Quaternary and Tertiary structure, 10,850 square miles in area, that extends westward, for nearly 100 miles, from the Atlantic border to " The Ridge," the granitic escarpment which by its rise determines the tidal limit in the great rivers of the State. This Tidewater plain, rectangular in form, is divided by Chesapeake Bay and the great estuaries of the Potomac, the Rappahannock, the York, and the James rivers, into five large peninsulas, which are subdivided by arms of the bay and tidal branches of the rivers into hundreds of smaller peninsulas, thus giving to the region great wealth of tidal shore outline fully 2000 miles so that nearly every square mile of its surface can be reached by tide-borne vessels. The nearly level surface of its north to south trending peninsulas, those of the eastern marine plain, the Quaternary ones, averages about 12 feet above sea-level ; their low-lying semi-insular position and their warm finely comminuted soils make these the highly favoured great market-garden or " trucking " portions of Tidewater. The north-west to south-east trending penin sulas, those of the western marine plain, the Tertiary ones, have more broken surfaces that vary in altitude from sea- level to about 100 feet, and are disposed in flat watershed ridges and slopes, terraces, and swamps, all deeply trenched by the secondary drainage. 2. Midland Virginia is the triangular area (12,470 square miles) which, 25 miles wide along the Potomac and 100 wide along the North Carolina line, extends from the Tidewater escarpment westward to the eastern base of the Atlantic coast range, the broken eastern range of the Appalachian Mountains. The elevation here varies from 100 to 200 feet above sea-level in the east to from 700 to 800 in the west ; once a gently east ward ly sloping plain, mostly underlaid by steeply clipping granitic and other Archaean rocks with included areas of Jura-Trias striking north-east to south-west, the rivers have deeply trenched into this, and so given it a greatly broken and varied relief through a moderate range of altitude ; it abounds in stream-valleys. This, with Piedmont and the Blue Ridge, was the first dry land, the oldest portion of Virginia. 3. Piedmont Virginia is the area (6680 square miles) of greatly diversified country, some 250 miles in length and 20 to 30 miles in width, that stretches between the Blue Ridge and the Coast Range mountains, including all of the latter and the east ward spurs and slopes of the former; its valleys, coves, and plains vary in altitude from 300 to 700 feet in the north-east to from 500 to 1000 in the south-west, while its included and bordering mountains range through all gradations from above 4000 feet down to the levels of its valleys. It is charmingly varied and picturesque, and adapted to a great variety of productions. 4. Blue Ridge Virginia is the Virginian portion (300 miles in length) of the great mountain chain of that name, with its numerous tablelands especially the Floyd-Carroll- Grayson plateau (1230 square miles) in the south-west, having an altitude of from 916 to 5700 feet. It is, for most of its length, a chain of two ranges : the eastern, the chief, in which numerous rivers have their origin, is a grand mountain mass, carved from the Archaean and eruptive rocks, forming the most striking feature of thousands of square miles of Virginia landscape ; the western is mainly composed of short ridges, formed from the easterly out crops of the Palaeozoic rocks, flanking the western slopes of the main range. 5. The Valley of Virginia is the Virginian portion (300 miles) of the length of the great limestone or Appa lachian valley of the Atlantic highlands, one that, made up of numerous subordinate valleys, extends with unbroken continuity from Canada to Alabama, and has for its whole length, with varying local names, the Blue Ridge on its eastern and the Kitta tinny or Great North Mountain on its western border. In Virginia this is a plateau-valley, embracing 7550 square miles, its greatly varied tillable surface ranging in altitude from about 500 to over 2500 feet and averaging fully 1000. Carved from the lime stones and limy shales and slates of the Cambrian group into an almost endless variety of valley and upland forms, the higher ones in gracefully rounded outline, all blending into one or more broad valleys, and bounded by grand mountain chains, this is indisputably one of the most desirable regions in the United States. 6. Appalachia (4500 square miles), a region of alter nating " rich " and " poor " valleys (according as they are carved from the lime-abounding or from the slaty sandstone rocks of the Silurian or the Devonian groups), is Virginia s portion of the Appalachian Mountains region proper, the one that lies between the Great Valley on the east and the great Carboniferous escarpment of the Trans-Appalachia plateau. Its general features are repetitions of long, parallel, straight, and level-crested mountain ranges many of them over 4000 feet succeeding one another in echelon, with narrow, trough-like valleys, ranging from 800 to 2700 feet, but these are diversified by the occa sional dying out of some mountain ranges and the conse quent widening of valleys, and by the widening of ranges into plateaus or their opening into double crests or lovely mountain "coves" and "gardens." It is a noted grazing and timber region. 7. Trans-Appalachia (mainly the 1200 square miles in Buchanan, Dickenson, and Wise counties) is the Virginian portion of the tableland that extends westward from the great Carboniferous escarpment or Alleghany " backbone." It is eroded from the Carboniferous rocks, and so is the great coal-bearing portion of the State. Climate. The State lies in the middle latitudes. It is open to Climate,

the sea on the east ; its great mountain chains guard it on the