Topography

“ Great generalizations are not often completed at a single step, and it is enough that every effort at advance should have part of its movement in the right direction. What I wish to show is that topographic form was regarded in the days of our eastern surveys, even by our first master of American topography, as a completed product of extinct processes. Topography revealed structure, but it did not then reveal the long history that the structure has passed through. ”

“ In a mountainous country, where the streams, swollen by sudden or heavy rains, sweep down much detritus into the valleys and plains, the great changes of topography thereby produced impress the imagination and dwell in the memory of the inhabitants. ”

“ Origin of the topography.—The topography of the plain surrounding the quartzite ridges, especially that part lying west of Devil's lake, is then an erosion topography, developed by running water. Its chief characteristic is that every depression leads to a lower one, and that the form of the elevations, hills or ridges, is determined by the valleys. ”

“ Topography. The land area on most charts is distinguished from the water area by a stipple or tint; on some charts the topographic features have, however, been depended upon to bring out the land from the water. The solid shore line is the high-water line, and should be clear on the chart; the area between high and low water is sanded or otherwise shaded on all charts. The relief of the land is represented by hill shading or by contour lines which are the successive curves of elevation on the land. ”

“ The basin type of topography calls into existence a set of relations quite distinct from either of those we have just described. Figure 34 represents the main facts. The rich and comparatively flat floor of the basin supports most of the people. ”

“ The importance of studying the geographical location of cities is due to the insight thus obtained into their structure, the distribution of population conforming to the same principles within a city as without. Topography operates in a similar manner, whether within or without a city, in causing population to flow along the same levels. ”

“ The more striking elements of topography accordingly aroused the curiosity of the earliest races who came to dwell among them, and to whom, in the infancy of the world, the forces of nature were more or less mysterious. ”

“ The Hills and Valleys.—Sir Charles Warren was the first to point out the necessity of ascertaining the depth of the rock below the present surface, in as many places as possible, and of referring all the measurements to one fixed datum, the level of the sea. In the study of the ancient topography the original appearance of the ground is the first consideration, for although a certain amount of soil may always have existed, still the ancient surface must have conformed far more closely to that of the rock than does the present. ”

“ The height is greatest along the inner or north-western border of the belt, and here a sub-mountainous topography has been produced by normal dissection, chiefly in the Tertiary cycle; the valleys being narrow because the rocks are resistant. ”

“ Foyers; and the other, “the waterfall of the moorish uplands,” which every one understands who walks up to it.
So much for the features of unappropriated nature, stereotyped, as it were, at once and for ever, in the old names of local scenery. But as into a landscape an artist will inoculate his sentiment and symbolise his fancy, so on the face of the earth men are fond to stamp the trace of their habitation and their history. Under this influence the nomenclature of topography becomes at once changed from a picture of natural scenery to a record of human fortunes. ”

“ We all know that in topography there are what are called water-sheds, sometimes high, sometimes low, and from these elevations flow in opposite directions the currents which there find their fountains. ”

“ When thus studied, the endless variety of the topography will be considered in its proper relations, and it will not seem as hopeless as it does now to gain a rational understanding and appreciation of geographic morphology.
We should first recognize the fact that a geographic individual is an area, large or small, whose surface form depends on a single structure. Boundaries may be vague, different individuals may be blended or even superposed, but in spite of the indefiniteness, the attempt to sub-divide a region into the individuals that compose it will be found very profitable. ”

“ After a little practice in map reading one becomes proficient and he will be able if in unsurveyed territory to make his own map. Get the compass directions from the camp of every prominent landmark with particular attention to streams and the ridges separating them. If one is out exploring it is a good idea to climb to the summit of some bare faced promontory and there study the topography of the country:—the location of the lakes, swamps, whither the streams run, the number and direction of the ridges, etc. ”

“ As much of the ground as possible is walked over, and its shape is delineated by contour lines sketched by eye, assisted by an aneroid barometer. In wooded country much of the topography may have to be shot in from the ship; sketches made from different positions at anchor along the coast with angles to all prominent features, valleys, ravines, spurs of hills, &c, will give a very fair idea of the general lie of the country. ”

“ They show none of the grandeur and ruggedness of the Highlands. The hills, on the whole, have smooth, rounded outlines, save here and there, where some crag of grey rock protrudes from the pervading mantle of green bent and purple heath. Yet the topography is sufficiently varied not to become monotonous, while the slopes in every season of the year glow with colour, spread over them like a delicate sheet of enamel. There is beauty enough in the landscape of itself to please, and even here and there to fascinate. ”

“ On seeing a relief map of one of the continents for the first time, there arises a sense of wonder and surprise, and as the realization dawns upon one of the continuity of the great mass of land represented, with its altitudes and depressions, and that it is one stupendous aggregation of soil, rock and vegetation, surrounded by a great expanse of water, a feeling of awe and astonishment is awakened. ”

“ To measure the elevation of the mountain-top above the sea, and to lay down upon our maps the mountain ranges of the earth, is regarded in geography as an important thing, and rightly so. Equally important is it, in bringing the physical geography of the sea regularly within the domains of science, to present its orography, by mapping out the bottom of the ocean so as to show the depressions of the solid parts of the earth’s crust there below the sea-level. ”

“ Without the aid of Geology the geographer cannot, in fact, discriminate between mountains of elevation and mountains of denudation; hence geographical terms so constantly in use as mountain-range and mountain-chain are very often applied by writers, ignorant of geological structure, to elevated regions which have no claim to be described either as chains or ranges. Some knowledge of Geology, therefore, is essential to us if we would have correct views of many of the grandest features of the globe. ”

“ Much the same may be said of the dikes of cooled magma which have been injected along preëxisting fractures.
The base of the geological map.—Modern topographic maps form an important part of the library of the serious student of physiography; they are the gazetteer of this branch of science. Every civilized nation has to-day either completed a topographic atlas of its territory, or it is vigorously prosecuting a survey to furnish maps which represent the relief with some detail, and publishing the results in the form of an atlas of quadrangles. ”

“ At every stage of the geographical cycle the land forms, as they exist at that stage, are concerned in guiding the condensation and flow of water in certain definite ways. Thus, for example, in a mountain range at right angles to a prevailing sea-wind, it is the land forms which determine that one side of the range shall be richly watered and deeply dissected by a complete system of valleys, while the other side is dry, indefinite in its valley systems, and sends none of its scanty drainage to the sea. ”

“ The anthropo-geography of mountain valleys depends upon the structure of the highlands themselves, whether they are fold mountains, whose ranges wall in longitudinal valleys, or dissected plateaus, whose valleys are mostly transverse river channels leading from the hydrographic center out to the rim of the highlands. Longitudinal valleys are not only long, but also broad as a rule and often show a nearly level floor.1215 They therefore form districts of considerable size, fertility, and individuality, and play distinct historical rôles in the history of their respective highlands. ”

“ The main object for which you are dispatched on this occasion, is, that from 45 or 50 degrees, or from the farthest point to which the land shall be found to extend southward within these latitudes, up to the northernmost extremity of the South-land, you will have to discover and survey all capes, forelands, bights, lands, islands, rocks, reefs, sandbanks, depths, shallows, roads, winds, currents and all that appertains to the same, so as to be able to map out and duly mark everything in its true latitude, longitude, bearings and conformation. ”

“ As the horizontal contours of any portion of the earth's surface must depend on the vertical, or, in other words, the various features which are marked on the map—the coast line, plains, rivers, vallies, lakes, hills, mountains, &c., being consequent on the different elevations of the various portions of the surface above the level of the sea ”

“ The features represented on the topographic map are of three distinct kinds: (1) inequalities of surface, called relief, as plains, plateaus, valleys, hills, and mountains; (2) distribution of water, called drainage, as streams, lakes, and swamps; (3) the works of man, called culture, as roads, railroads, boundaries, villages, and cities.
Fig. 13.—Diagram showing the outline of dunes in process of destruction. Seven Mile Beach, N. J. (N. J. Geol. Surv.) Fig. 14.—Illustrates the protective effect of vegetation against wind erosion. ”

“ At the base of the mountains themselves, where the bold relief begins, is always a piedmont zone of hilly surface but gentler grade, at whose inner or upland edge every phase of the historical movement receives a marked check. Here is a typical geographical boundary, physical and human. It shifts slightly in different periods, according to the growing density of population in the plains below and improved technique in industry and road-making. ”

“ As the mere existence of mountain range, desert, sea or river, may be essentially the influence which has led to the growth or downfall of empires, it is clearly seen that a sound knowledge of structural geography is absolutely necessary for all intelligent study of history ”

“ As a work of art, graphically delineating the configuration of a district of surpassing beauty and variety of scenery, it will, perhaps, possess greater interest to the ordinary observer than any scientific value of accuracy and completeness could give it. If a person were called upon to construct an ideal map which should group together specimens of all types of topographical form and the conventional signs known to the draughtsman, he could hardly derive from his imagination a chart more comprehensive than this. ”

“ The great typical forms already considered, highland, plateau, mountain, lowland, terrace, and river, which all claim so large a share of attention in studying their physical characteristics, are no less worthy of careful attention, in consequence of their influence on human culture. ”

“ The distinctive characteristic of a mountain land is the height of isolated groups. Great differences of elevation within small distances characterize mountain regions; small differences within great distances characterize plateaus. The plateau depends upon uniform evenness of surface, or an approximation to it, over a large extent of territory. The mountain range is the exact opposite, the development of all kinds of extremes within a limited space, and the consequent individualization of the locality where it stands. ”

“ The chief features of mountain relief reappear on a large scale in the continents, which are simply big areas of upheaval lifted above sea level. The continents show therefore homologous regions of lowlands, uplands, plateaus and mountains, each district sustaining definite relations to the natural terrace above or below it, and displaying a history corresponding to that of its counterpart in some distant part of the world, due to a similarity of relations. ”

“ An essential as well as an advantage in this extension of the study of geography will be the definition of types and terms, both chosen in accordance with a rational and if possible a natural system of classification. Types and terms are both already introduced into geographic study, for its very elements present them to the beginner in a simple and rather vague way: mountains are high and rough; lakes are bodies of standing water, and so on. ”

“ These popular efforts to explain physical phenomena [Pg 52] which, from the earliest days of human experience, have appealed most forcibly to the imagination, have survived longest in the more rugged and remote regions, partly, no doubt, because these regions have lain furthest away from the main onward stream of human progress, but partly also because it is there that the most impressive topographical features exist. The natural influence of mountain-scenery upon the mind is probably of an awe-inspiring, depressing kind. ”