221 



ALLEGHANY. 



ALLEGHANY. 



222 



system which runs through the eastern side of the continent of 

 North America. They were called the Appalaches, or Appalachian 

 Mountains, by the French, who first became acquainted with them at 

 their southern extremity, from the Indian name of a river that flows 

 into the Gulf of Mexico, in Appalache Bay ; but the English, who visited 

 them principally in their more northern parts, preserved the Indian 

 name there given of Alleghanies, which is supposed to mean the Endless. 

 The Alleghany system consists of numerous parallel chains, some of 

 which form detached ridges, extending, in most instances, in the same 

 direction as the entire system which they contribute to form. Taken 

 as a whole, it has a range which does not deviate materially from N.E. 

 to S.W., and it extends about 1200 miles in length. The northern 

 and southern extremities of this mountain-system are not well defined, 

 but the elevations which form a part of the whole system may be 

 traced from the state of Maine into Alabama. The most remarkable 

 chains are the Blue Ridge, which lies nearest to the Atlantic, and 

 stretches from North Carolina to the Hudson River, in the state of 

 New York ; the Kittatinny Chain, which extends from the north part 

 of New Jersey, across Pennsylvania, and the west of Maryland, to 

 Virginia; the Alleghanies Proper, in the western part of Virginia and 

 the central parts of Pennsylvania ; the Cumberland Mountains, on the 

 eastern boundary of Tennessee and Kentucky ; the Catskill Moun- 

 tains, in the state of New York ; the Green Mountains, in the state of 

 Vermont; the Highlands, eastward of the Hudson River; and the 

 White Hills in New Hampshire. In the whole of the Alleghany 

 system, there are no great detached mountain-peaks; the greatest 

 elevations are in the White Hills of New Hampshire, where Mount 

 Washington rises to the height of 6631 feet above the sea, its base 

 being at an elevation of 1888 feet. The summit is much below the limit 

 of perpetual snow. Moosehillock, another of the White Hills, is 4636, 

 and Gnui'l Monadnoc, 3254 feet. In the Green Mountains, Killington 

 Peak is 3924 feet above the sea ; in the Catekill Mountains, Round 

 Top in 3804, and the High Peak, 3718 feet above the tide-level of the 

 Hudson, about 18 miles distant. The Peaks of Otter, in the Blue 

 Ridge, Virginia, are said to be about 4000 feet above the sea-level ; 

 though the general elevation of the Blue Ridge in Virginia is far 

 below this height. Table Mountain, in South Carolina, is supposed to 

 be not less than 4300 feet above the sea. Canawhee Mountain in 

 Georgia, the southern extremity of the Blue Ridge, i 1500 feet. 



The Alleghany Mountains do not form a high dividing line between 

 the waters which flow into the Atlantic on one side, and into the Missis- 

 sippi on the other. They cover a widely-extended area of about 100 

 miles in breadth, only one-third of which is occupied by the mountain- 

 chains, the rest being the intermediate valleys. The rivers which rise 

 in them flow in long valleys between the chains, and are deflected 

 sometimes to the east, and sometimes to the west, after passing nearly 

 at right angles through depressions in the ridges, or through deep 

 rents in the mountains, as at Harper's Ferry, in Virginia, where the 

 united Potomac and Shenandoah cut the Blue Ridge at right angles. 

 From the Connecticut River, the most northern of the great rivers 

 belonging to the system, to the Alatamaha of Georgia, we find a series 

 of large rivers which, originating within the Alleghanies, or on their 

 eastern margin, flow to the Atlantic. The line of the great watershed, 

 between the streams that run to the Atlantic, and those that flow into 

 the Gulf of Mexico, runs from the sources of St. -John's River, on the 

 north-western limit of the state of Maine, to the Point of Florida, 

 almost following the inflection of the coast, but the mountain-system 

 crones that line at an angle of about 30 degrees. The land between 

 the sea-coast and the foot of the most eastern of the chains, is of very 

 unequal breadth ; at the Hudson River, the Atlantic almost washes 

 the base of the mountains, but from that point southward there is a 

 gradual increase in the breadth of the Atlantic Slope, as it is called, 

 as far as Cape Hatteras, in North Carolina ; and from that point to 

 the mouth of the Alatamaha in Georgia, the coast runs nearly parallel 

 to the mountains, at a distance of about 200 miles. 



The western slope of the Alleghanies falls by a gentle but broken 

 descent to the Mississippi ; it is upwards of 1000 miles in length, and 

 about 300 miles in width, from the river to the base of the mountains, 

 covering an area of about 300,000 square miles, unbroken by any other 

 than gently rising hills, but deeply furrowed by rivers over its whole 

 surface. Nowhere can the wearing effects of rivers be more advan- 

 tageously studied, for their channels do not appear to have been 

 formed by rents and dislocations of the ground, the strata being 

 usually horizontal, but by the erosion of a stream. The hills parallel 

 t-i the Alleghanies on the western slope consist, hi their lower parts, 

 of transition slate and limestone, in highly inclined beds, which are 

 covered near their summits by coal-measures and superior secondary 

 formations, in unconfonnable and horizontal stratification. Hills, 

 separated by valleys several miles wide, are composed of the same 

 horizontal strata, the identity of the beds on both sides of the valley 

 being recognisable ; it seems therefore a legitimate conclusion that 

 the strata were once continuous over the valley, and it is difficult to 

 conceive how the gap could have been produced, in such circumstances, 

 except by the scooping out of water acting with great force, and for a 

 considerable period. 



In the northern parts of the Alleghanies, a considerable tract of 



try is occupied by primary strata, such as gneiss, mica-elate, 



clay -slate, and granular limestone, associated with granites, serpentines, 



and traps, under various aspects, underlying and penetrating the 

 strata. Grauwacke sandstone and slates, and transition limestones, are 

 however more abundant in this mountainous range than the primary 

 strata. Grauwacke slate forms the western margin of the primary 

 country of New York and New England, and also of the great body 

 of the Alleghanies Proper and of the Catskills. It is still more widely 

 extended in the north, occupying much of the surface in the state 

 of Vermont, the northern parts of the state of New York, and Canada. 

 In the Alleghany Mountains of Pennsylvania, Maryland, and Virginia, 

 its beds are of great thickness, and form, in some instances, the pre- 

 vailing rocks, being however almost invariably overlaid by sandstone. 

 Transition limestone occurs over a great extent of country along the 

 north-western side of the Alleghany chain, associated with the grau- 

 wacke slate, but generally inferior to it. It is found in Vermont 

 alternating with grauwacke slate, and is separated from a secondary 

 limestone in the valley of Lake Champlain by a red sandstone, which 

 forms the upper part of a range of hills called the Snake Mountain. 

 In the western part of Massachusetts, and along the eastern side on 

 the Hudson River in New York, it lies upon primary clay-slate. North- 

 east of the Hudson, this limestone nowhere occupies any great extent of 

 country. Crossing the Hudson, and proceeding south-west, little of this 

 limestone is seen in the lower part of New York, but it becomes more 

 abundant in the western parts of New Jersey and Pennsylvania, forms 

 the lower part of the ridge in southern Pennsylvania and Virginia, and 

 extends nearly to the south-west termination of the mountains, between 

 the Alabama and Tombeckbee rivers. It contains many caves, some 

 of which are of great extent, and in these caves fossil bones of various 

 animals have been found. Arenaceous and conglomerate grauwackes 

 are perhaps the most frequent forms in which the transition rocks 

 present themselves. A red sandstone partially covers the lower levels 

 of the primary strata, from 12 miles south of Connecticut River to near 

 the Rappahannock River in Virginia, a range of nearly 400 miles ; and, 

 though often interrupted, it retains a remarkable degree of uniformity 

 throughout the whole distance. The sandstones, in highly -inclined beds, 

 prevail very generally throughout the middle and eastern chains in 

 Pennsylvania and Maryland. Near the summit of the Alleghanies 

 of Virginia, the grauwacke passes into a red sandstone, which 

 gradually assumes a horizontal position. 



In Pennsylvania there is a vast deposit of anthracite coal, associated 

 with sandstones and slates, which American geologists have hitherto 

 described as belonging to the transition or grauwacke series. The 

 great Pennsylvanian coal-fields are situated in the valleys of the 

 Susquehanna, Lackawanna, and the Lehigh and Schuylkill rivers, the 

 two last being affluents of the Delaware. The coal-region along 

 the Susquehanna River is in the valley of Wyoming, and runs up into 

 the valley of its tributary the Lackawanna. It is between 60 and 70 

 miles long, by about 5 miles broad. The beds of coal break out in 

 the face of the precipices, in the banks and beds of the rivers, and 

 occur in several alternations with conglomerates, sandstones, and 

 slates. In these sandstones and slates, as well as in the coal itself, 

 there are numerous vegetable impressions, belonging to the fern tribe 

 and others. 



The coal-region of the Lehigh River is chiefly wrought at a place 

 called by an Indian name Mauch Chunk. The coal here also forms 

 alternating beds with sandstones and slates, and is extracted at the 

 summit of a mountain 1500 feet above the level of the sea, in a 

 quarry open to the day. The beds are usually from 20 to 25 feet 

 thick, but in some places they swell out to 54 feet, and they are 

 known to extend over many miles. These mines, together with others 

 on the Schuylkill River, are an immense source of wealth to the state 

 of Pennsylvania. They are extensively wrought, and the coal is 

 conveyed by railroads to the banks of the navigable rivers. Deposits 

 of the same kind of coal are wrought in Rhode Island, and in 

 Worcester County in the state of Massachusetts. Bituminous coal of 

 the same sort as the regular coal-measures of Europe is found in 

 several places on the Atlantic slope. About 10 or 12 miles west of 

 Richmond, in Virginia, there is such a deposit, from 20 to 25 miles 

 long and about 1 miles wide ; it is situated in an oblong basin, 

 having a whitish freestone and slaty clay, with vegetable impressions 

 alternating with the coaL It lies upon and is surrounded by primary 

 rocks. Bituminous coal is abundant also in Tioga County, in the 

 state of New York. About one mile west of the summit of the 

 Alleghanies, on the road from Philadelphia to Pittsburg, the coal- 

 measures appear, and descending into the valfcys, the transition 

 strata again emerge. 



There are, in several other situations in the Appalachian system, 

 very extensive deposits of bituminous coal ; one of the most remark- 

 able of which is in the vicinity of Pittsburg, on the Ohio, where it is 

 associated with ironstone, as in Staffordshire. A mountain-group, 

 called the Laurel Ridge, lies between Pittsburg and the Alleghanies, 

 and is separated from the latter by a wide valley. Near the summit 

 of the mountain are strata of sandstone and bituminous shale, 

 alternating with coal, which is thick enough to be worked. These 

 coal-measures are very little lower than the summit of the Alleghanies, 

 and as they are horizontal, they must have been raised up from the 

 bottom of the sea in a vertical direction to this great height ; a 

 circumstance which perhaps seems to indicate rather a gradual 

 upheaving of the mountains than a sudden and violent action. The 



