Encyclopædia Britannica, Ninth Edition/Pennsylvania

PENNSYLVANIA, one of the original thirteen States of the North American Union, lying between 39° 43' and 42° 15' N. lat., and between 74° 40' and 80° 36' W. long., is 160 miles wide, and more than 300 miles long from east to west. Its northern, southern, and western border-lines were meant to be straight; the eastern follows the course of the Delaware river. It is bounded by the States of New York and New Jersey on the N. and E., by Ohio on the W., and by Delaware, Maryland, and West Virginia on the S. At its north-west corner a small triangular addition gives it a shore-line of 40 miles, with one good harbour, on Lake Erie. At its south-eastern corner, a circle of 10 miles radius (struck from the court-house at Newcastle) throws a small area into the State of Delaware. Its surface, subdivided into sixty-seven counties, measures nearly 28,800,000 acres or 45,000 square miles; less than one-half of its acreage is in cultivated farms, and only 1,000,000 of the people live in separate farm-houses. Out of a population of 4,283,000, nearly 2,000,000 lived in towns and cities in 1880, and more than 2,000,000 in country hamlets or factory villages, at iron mines and furnaces, at coal-mines and coke-ovens, at lumber-camps and oil-wells, or along the many lines of canal and railroad which traverse the State in all directions.

Physical Features.—Pennsylvania is topographically divisible into three parts: a south-east district, the open country between the South Mountains and the sea; a middle belt of parallel valleys separated by low parallel mountain-ridges; and a northern and western upland, behind the escarpment of the Alleghany Mountain. One and a half millions of its people inhabit the fertile and highly-cultivated south eastern triangle, which is nowhere more than 600 or 700 feet above the level of the sea. One million inhabit the middle belt of higher-lying valleys, rich in iron ore and anthracite coal. One and a half millions occupy the great bituminous coal and oil regions of the northern and western counties, elevated from 1000 to 2500 feet above the sea,

which constitute at least one-half of the State, and drain, not eastward into the Atlantic, but northward into the St Lawrence and westward into the Mississippi.

The valleys of the middle belt are of two characters, distinguished by the farming population of the Atlantic States as &ldquo;rich valleys&rdquo; and &ldquo;poor valleys.&rdquo; The former, whether large or small, are completely enclosed and comparatively level arenas of limestone land, surrounded by rocky and wooded barriers, less than 1000 feet high, through narrow gaps in which streams enter or issue. A curiously sculptured slate-terrace, half the height of the encircling mountain, overlooks each of these secluded valleys. Their entire limestone floor has been under cultivation for a century, and the best iron-ore deposits of the State and its oldest mines are situated in them. They are gardens of fertility, yielding heavy crops of wheat, rye, and maize to the frugal, thrifty, and laborious descendants of their early settlers. Innumerable caverns ramify beneath the surface; sink-holes receive the drainage of the fields; many of the water courses appear and disappear beneath sunken arches of limestone; and wells are the chief source of supply. Old orchards and great planted trees abound, and more picturesque landscapes cannot be found. Nittany, the largest of these isolated valleys, occupies the centre of the State. It is 60 miles long, but its greatest width is only 10 miles; and it is subdivided at its north-eastern end by long projecting mountain-spurs into narrow parallel coves, each of which is known by a special name, Brush valley, Penn's valley, &amp;c. Sinking Spring valley is at its south-western end, and here it is traversed by the Little Juniata river, along the banks of which runs the Pennsylvania Railroad. A narrow valley, called Canoe valley, leads southward into Morrison's cove, which is half as large as Nittany valley. The next largest limestone valley is Kishicoquilis, 40 miles long by 5 miles wide, ending southward in a point, and split at its north-east end into three. German Amish (Mennonite sect) and Scotch-Irish Presbyterian settlers, separated by an ideal cross line, have made this valley famous for its loveliness and wealth. Farther south is M&lsquo;Connell's cove, west of this Friend's cove, and still farther west Millikin's cove. Two little oval holes in the mountains north-east of Nittany valley, Nippenose valley and Oval valley, and two long slit-like depressions in Tuscarora and Black Log Mountains conclude the short list of these remarkable limestone threshing-floors of Pennsylvania.

Across the whole State, however, stretches the Great Valley in a wide and gentle curve from east to south, one-half its surface covered with the soil of the terrace-slate, the other half with the same limestone soil which causes the exceptional fertility of the isolated valleys above enumerated. This very remarkable feature of the Atlantic side of the continent extends in an unbroken line for nearly 1000 miles, from eastern Canada to the lowlands of the Gulf of Mexico, only 150 miles of its length being in Pennsylvania, where its average width may be called 15 miles. Everywhere on its north-west side rises a sharp and regularly level-crested ridge, about 1000 feet high, heavily timbered. On its other or southern side a range of irregular mountain-land completely secludes the Great Valley from the seaboard, except for about 50 miles in Pennsylvania. This mountain-range is known in Vermont as the Green Mountains, in Massachusetts as the Taconic Mountains, in New York and New Jersey as the Highlands, in Pennsylvania and Maryland as the South Mountains, in Virginia as the Blue Ridge, in North Carolina as the Unaka or Smoky Mountains. In their northern extension they rise to heights of 3000 and 4000 feet; in the southern States they have summits from 4000 to 7000 feet above the sea. In Pennsylvania few parts of the range exceed 1500 feet; and at the broken

gap of 50 miles already mentioned the Great Valley limestone land protrudes southward through the interrupted range, to make of Lancaster the richest agricultural county in the State. Before the era of railways Lancaster county made the markets of Philadelphia the cheapest and most luxurious in the world. It was on this exceptional outspread of the Great Valley limestone that the Germans of the first immigration settled. The limestone plain of Lancaster spreads west across the Susquehanna river into York county, and east into Berks and Chester counties to within 20 miles of Philadelphia. The whole plain swarms with life; the houses are small, but the stone barns are of colossal size, 100 and even 150 feet long and from 30 to 50 feet high, the barnyard-wall supported on ranges of heavy columns, while on the other side of the building an earthen slope ascends to the great barn door.

The eight counties which lie along the face of the South Mountains, in the south-eastern region of the State, are in the highest state of cultivation, and resemble the most picturesque rural districts of England,—a country of rolling hills and gently sloping vales, with occasional rocky dells of no great depth, and low cascades utilized for grist-mills, factories, and machine shops; a country of wheat, rye, maize, potatoes, tobacco, turnip-fields, orchards, meadows, and patches of woodland; a country of flowing water, salubrious, fertile, and wealthy; dotted with hamlets, villages, and towns, and with the country-seats of affluent citizens. But the region as a whole is divisible into at least four districts, differing as much in population as in soil and situation. The counties of York and Adams, lying west of the Susquehanna river along the Maryland line, are inhabited by Germans, who for the most part still use the patois of their fatherland, mixed with English words and phrases. The counties of Montgomery and Bucks, lying between the Schuylkill and Delaware rivers, have a mingled population of the descendants of Germans, Quakers, and French Huguenots. The hilly district of northern Chester is also partly German. Southern Lancaster, southern Chester, and Delaware counties support the most intelligent and virtuous population in the State, largely composed of the descendants of Penn's colonists, who have mostly escaped the narrowing and enervating influences of the city, and enjoy the mental and physical activity, the simplicity of manners, and the loyalty to truth, justice, and charity which characterized the Quakers at the origin of the sect in England. The district which they inhabit is a veritable fairyland, and its principal town, Westchester, has been for a long time one of the notable centres of scientific life in the State.

Climate.—The climate of so great a State is necessarily various, and is made more variable by its situation on the eastern side of the continent facing the Gulf Stream. The north-west wind is dry and cold in winter, the south-west wind always mild and rainy, and the south-east ocean wind wet and sultry in summer; but the dreaded north-easters of New England lose much of their rigour by the time they reach the Delaware. The northern highlands of the State are buried under 4 or 5 feet of snow four months of the year. The southern middle counties enjoy genial weather the whole year round, interrupted only by a few short intervals of intense heat or cold, never lasting more than three consecutive days. The midland valleys are very hot in midsummer and very cold in mid-winter, the thermometer ranging between 0° and 100°, with a not unfrequent sudden fall after a sultry week of 30° or 40° in a few hours, ending with thunderstorms, and followed by dry, clear, cool weather, with winds from the north-west. The climate of the south-western counties is comparatively dry and equable, but with a sufficient annual rainfall, and plenty of snow in winter, productive of great river-floods

in spring. The average annual rainfall ranges from 36 inches in the western counties to 42 inches at Philadelphia. Destructive &ldquo;freshets&rdquo; descend the eastern rivers when the ice breaks up; for the Delaware and Susquehanna rivers are almost every year frozen over from tide-water to their sources; thunderstorms happen in the midst of winter; the January thaw is always to be apprehended; and when heavy rains break up the ice and it accumulates in the gaps of the mountains, the main river-channels become scenes of inevitable disaster. In 1837 the valley of the Lehigh was swept clean for 60 miles, the dams and locks of the canal were all destroyed, and every bridge and mill disappeared. Along the lower Susquehanna the floating ice has often been piled upon the railroad embankment to the height of several yards. Even in midsummer a heavier downpour than usual in 1836 carried destruction through the valley of the Juniata. But the affluents of the Ohio river in the western part of the State are subject every year to this danger.

Geology.—For unknown geological reasons Pennsylvania is peculiar for exhibiting the Palæozoic system in its

maximum development, that is, from the Permian formation down to the base of Murchison's Lower Silurian, with a total thickness of more than 40,000 feet at the eastern outcrops, diminishing to half that amount in the western counties. As all the formations are thrown into great anticlinal and synclinal folds, and cut through transversely by the rivers, they can be measured along numerous continuous and conformable section lines. Near Harrisburg, at Pottsville, and at Mauch Chunk the Carboniferous, Devonian, and Upper Silurian rocks, standing vertical, show a cross section 5 miles thick. At the Delaware and Lehigh water-gaps the Lower Silurian slates are 6000 feet thick. In Canoe valley the underlying Lower Silurian limestones have been measured 6500 feet thick. In the south-western corner of the State about 1000 feet of Permian rocks overlie the Coal-measures proper. Thus the following Palæozoic column can be studied with peculiar advantages in Pennsylvania, many of its more important stages either becoming greatly attenuated or wholly disappearing when followed into the neighbouring States of New York, Ohio, and Virginia.



Geological Map of Pennsylvania.

The geology of south-eastern Pennsylvania is not understood. There can be no doubt that the copper-bearing porphyritic Huronian system is well represented in the South Mountains, south of the Chambersburg fault, on the borders of Maryland; but the systematic age of the gneisses, mica schists, garnetiferous schists, serpentine and chrome iron rocks, of the Philadelphia belt, commencing at Trenton,

crossing the Schuylkill river on a section line 15 miles wide, and extending through Delaware and Chester counties into Maryland, is still under discussion, some geologists considering them of pre-Cambrian age and others regarding them as metamorphosed Silurian rocks. They contain minute quantities of gold and are evidently a prolongation of the great gold-bearing belt of Virginia and the Carolinas.


 * (J. P. L.&mdash;C. G. A.)