I—Physical Geography
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I—Physical Geography. INDEX TO PLATES. TOPOGRAPHIC MAP ............................................... Plate 1 SPRING AND SUMMER RAINFALL................Plate 4 MEAN TEMPERATURE, JANUARY AND JULY, Plate 2 ANNUAL RAINFALL..................................................Plate 4 MEAN ANNUAL TEMPERATURE......................... Plate 3 RIVER BASINS........................................................... Plate 5 HYPSOMETRIC SKETCH ....................................... Plate 3 FORESTRY—ESTIMATED TIMBER SUPPLY, Plate 5 T o p o g r a p h y . — In describing the physical near Lynchburgh, its height is over 4,000 feet. The western member of this system is features of the United States, we have first to Entering North Carolina it develops into a known in different places under different consider the general topography of the country series of ranges and cross-ranges, forming a names. In Pennsylvania it is called the — its framework, as it may be called— since tangled mass of mountains, which cover the Alleghany plateau. In West Virginia, where upon this depends, to a great extent, its whole western part of the state and rise to it is extremely broken and eroded, different temperature, aridity of atmosphere, and rainfall. heights, in the peaks, of from 5,000 to 6,000 parts of it are known as the Alleghany This framework consists, in general terms, feet, while a number of the most prominent mountain, Great Flat Top mountain, etc. In of two great mountain systems, of which the peaks are considerably above the latter figure. Kentucky and Tennessee it is known as western, the principal one, is known as the Among them is Mt. Mitchell — the highest the Cumberland mountain or plateau. This Cordilleran system of North America; and the summit east of the Cordilleras— which is 6,707 portion of the system presents everywhere, eastern, as the Appalachian system. Between feet in height. In these mountains the line of however modified by erosion, the general the two lies a broad basin occupied by the the Blue Ridge proper can still be traced, character of a great plateau, breaking off Mississippi river and its branches, and the forming, most of the way, a water-divide sharply toward the valley and sloping grad chain of the Great Lakes. between the streams flowing directly into the ually in the opposite direction. Generally The Appalachian system enters the United Atlantic and those flowing into the Tennessee. speaking, its crest forms the divide between States in the northern part of New England It has here the character of a plateau, sloping the waters flowing directly into the Atlantic and northern New York, and, extending gradually on the northwest, but pitching off or into the Tennessee river, and those flowing in a general southwesterly direction, ter abruptly on the southeast. This mass of directly into the Ohio or into the Cumberland. minates in northern Georgia and Alabama. mountains extends into Georgia and north Exceptions may be found in the case of Throughout most of its extent it consists of eastern Alabama, finally terminating in long the Susquehanna and Delaware rivers in two members: the eastern, known as the narrow ridges. Pennsylvania, the New river, a branch of the Blue Ridge; the western, as the Alleghany The depression between the Blue Ridge Kanawha, in southwestern Virginia, and the or Cumberland mountains. These two are and the Cumberland mountains, known as The Potomac, which cuts back a short distance separated throughout Maryland, Virginia and Great Valley, is by no means a simple, smooth into the plateau in northern W est Virginia. Tennessee by a valley, known in different expanse. It is traversed by numberless ridges, In some localities, as in eastern Tennessee, this parts by the names of its principal streams. most of them low, although several rise to plateau has suffered comparatively little In northern Virginia it is the Shenandoah heights of between 1,000 and 2,000 feet above erosion, but throughout W est Virginia and valley, and in southwestern Virginia and the valley. These ridges are remarkably northwestern Kentucky erosion has so nearly eastern Tennessee, the Tennessee valley. continuous, extending, with slightly sinuous obliterated its form that little of the plateau The Blue Ridge first appears in northern courses, for hundreds of miles. In Pennsyl character is left. The slight inclination of the New Jersey. Detached portions of it may, vania they are extremely numerous. Part of strata, however, and the fact that all of the indeed, be traced to the eastern bank of the the valley occupied by the Shenandoah river in mountain and hill summits are, approximately, Hudson river, in the line of the Highlands. Virginia, is but very little diversified, only one upon the same level, together with the erratic The Delaware crosses it at the Delaware Water or two ranges being contained in it, while in course of the drainage, all indicate this as- the Gap. Within the State of Pennsylvania it is the high country about the heads of the original form of the region. known as the South Mountain, a range of but Shenandoah, James and New rivers, the ridges Toward the northeast, in New York and little topographic importance. It then rises are extremely numerous and much broken. New England, the character of this system gradually, however, and, at Harper’s Ferry, Farther to the southward they gradually of mountains becomes obliterated. In its where the Potomac cuts through it, has a become less numerous and of less importance, place we have the isolated masses of the height above the river of some twelve or so that, below Knoxville, Tenn., the valley Catskills, the Adirondacks, the parallel fifteen hundred feet. A t the Peaks of Otter, is again almost a plain. ridges of the Green mountains and the XX SCRIBNER'S STATISTICAL ATLAS Berkshire hills, the White mountains of some small ranges of hills in northern through New Mexico to 4,000 feet at the New Hampshire, and the irregularly grouped .Michigan and Wisconsin. Mexican boundary. The ranges in Montana rise summits of Maine. It is a singular fact, Westward from the Mississippi the country to heights of from 9,000 to 11,000 feet in the however, that in this part of the country, rises in a long incline to a great continental highest peaks, while the passes range from where the range has lost its continuity, are plateau, which is crowned by the ranges 5.000 to 6,000 feet. Southward the mountains found, with the exception of the North Carolina forming the Cordilleran system. The summit increase in elevation. The peaks of the Wind mountains, the highest peaks in the whole of this plateau forms the continental watershed. River range rise to heights of nearly 14,000 feet. system; among them are Mt. Marcy, in the In western Montana this crest-line has an From the end of this range, at South Pass, to Adirondacks, with an elevation above sea level elevation above the sea of from 4,000 to 5,000 a point near the Colorado boundary, the Rocky of 5,379 feet, and Mt. Washington, the culmi feet. It rises in western W yoming to heights mountains have only a theoretic existence, nating peak of the White mountains, which rises of from 7,000 to 8,000 feet, while in Colorado it being represented only by broad plateaus, 7,000 to a height of 6,294 feet above the sea. is still higher, ranging from 8,000 to 10,000 to 8,000 feet in elevation— plateaus so flat that, East of the Appalachian system there feet, the latter elevation being reached in the although carrying the continental water-parting, extends to the coast a gradually sloping plain. South Park. In New Mexico it diminishes in it is impossible to tell for many miles in what In the neighborhood of the mountains it is height, passing out of the country with an direction the water flows. In the southern slightly broken by isolated ridges and minor elevation, Just west of the Rio Grande, not part of Wyoming, about the heads of the undulations. In Maine the Atlantic slope is much above 4,000 feet. The basin of the North Platte river, mountains rise again from terminated by a rocky, broken coast, cut by deep Colorado and Green rivers forms a general the plateau. The easternmost of these is known bays and with thousands of islands scattered depression in this plateau, which rises again in Wyoming as the Laramie range, in along its front. From Massachusetts Bay to the westward, reaching its second summit Colorado as the Colorado or Front range, southward the coast begins to change its line in eastern Nevada, where, in the northern whose peaks reach a height of 14,300 feet. It form to a low, sandy shore, and on the New part of the state, it has an elevation of terminates in Pike’s peak, Just north of the Jersey coast there is the typical southern 6,000 feet, whence the height diminishes rapidly Arkansas river. Westward of this is the Park shore, with a low reef facing the sea, back southward. range, between which and the Front range are of which are bays or lagoons and coast The Cordilleran is an extremely complex the high mountain valleys, known as North, swamps. These swamps grow broader south system of ranges. In its widest part, that is Middle and South Parks. South of the ward, until on the coast of North Carolina between latitudes 370 and 420, it has a breadth Arkansas river the front rank is taken up by they cover a very considerable area. To a of no less than 190 of longitude. Crossing it the Sangre de Cristo range, which, with a great extent they are uninhabitable.