Part I.
PHYSIOGRAPHY OF NORTH AMERICA.
THE continents of the earth have two distinct types of form,—the one regular, symmetrical, triangular in outline; the other without these regularities of shape. To the first of these groups belong the continents of Africa and Australia of the Old World, and the two Americas of the New; to the second, the massive continent of Europe and Asia. Some have sought to reduce the continent of Asia to the same type as that of the other continents; but a glance at a map of the hemispheres will show how different is this Indo-European continent from the other land-masses.
These general features of the continents are not only of scientific interest; they are of the utmost importance to the history of man’s development upon these several lands. It is not without meaning, that, while man has existed for a great length of time upon all the continents, the only original civilizations that have been developed have been on the lands of the Indo-European continent. Working on several different lines of advance, several diverse races—Aryan, Semitic, Chinese, and perhaps others—have risen from the common plane of barbarism, and have created complicated social systems, languages, literatures, and arts; while on the four other continents, despite their great area, greater fertility, and wider range of physical conditions, no race has ever had a native development to be compared with that undergone by the several successful races of Asia and Europe.[1]
In this great Old-World continent there are many highly individualized areas, each separated from the rest of the continent by strong geographical barriers; it has a dozen or so of great peninsulas upon its seaboard, many great islands off its shores, and the interior of the land is divided into many separated regions by mountain ridges or by deserts. It is a land where man necessarily fell into variety, because of the isolation that the geography gave. If we look at the other continents,—namely, the Americas, Africa, and Australia,—we find that they want this varied and detailed structure. They each consist of a great triangular mass, with scanty subordinate divisions. In all of them put together there are not so many great peninsulas as there are in Europe. If we exclude those that are within the Arctic Circle, there are but few on the four regular continents, none of which compare in size or usefulness to man with the greater peninsulas of the Old World. The only one of value is that of Nova Scotia, in North America.
These regular continents are all in the form of triangles, with their apices pointing towards the southern pole. Near either long shore lie the principal mountain systems that give definition to the coast line. The middle portion of each continent is generally a region of plain, somewhat diversified by lesser mountain systems. Along either shore is a narrow fringe of plain land to the east and west of the main mountain chains. Near the northern part of the continent, and aiding to define the base of the triangle, there is another system of mountains having a general east and west course. With the exception of North America, none of these regular continents have seas inclosed within their areas,—such bodies of water as form so striking a feature in the Asiatic continent, which is indeed a land of mediterranean seas.
In a word, these continents are characteristically as simple as the Asiatic continent is varied. Their mass is undivided, and their organic or human histories are necessarily less diversified than in such a land-mass as Asia.
The continent of North America is, of all the triangular continents, the most nearly akin in its structure to the great Old-World land. In the first place, it is the only one of these continents that has the same general conditions of climate; then it has a far greater diversity of form than the similar masses of South America, Africa, and Australia. North America has several considerable seas inclosed within its limits or bordering upon its shores; its mountain systems are more varied in their disposition than in the other regular continents. So that in a way this continent in its structure lies intermediate between the Asiatic type and what is considered the normal form of continents.
Although this varied structure of the continent of North America makes it more fit for the uses of man than the continents of Africa, South America, and Australia, there are certain considerable disadvantages in its physical conditions. To show the relation of these evil and fortunate features, it will be necessary for us to consider the general geography of the continent somewhat in detail.
The point of first importance concerns the distribution of heat and moisture over the surface of the land; for on these features depends the fitness of the land for all forms of life. The influences which principally determine the climate of a continent come to it from the neighboring seas. The moisture arises there, and finds its way thence to the land; and the heat or coolness which modifies the land climate comes with it.
North America faces three oceans. On the north is the extremely cold Arctic Sea, mostly covered by enduring ice: it is the extreme coldness of this sea, and its ice-clad character near the continent of America, that in good part causes the great severity of its winters. Where the Arctic Sea lies against Europe and Asia it is partly warmed by the Gulf Stream, and so is not completely ice-bound even in winter; but that part of it which lies near the northern coast of America is ice-bound the whole year, and the winds that come from it are many degrees below those that come over open water.
Both the Atlantic and Pacific oceans send streams of warm water against the American coast. But the Gulf Stream has actually very little direct effect upon our climate; it only touches the coast about the Gulf of Mexico, where the temperature is naturally so high that its warming power is not felt. It then leaves our coast, to give its warmth to the shores of Europe and to the European part of the Arctic Ocean. The Pacific current corresponding to the Gulf Stream is feebler than the Atlantic current, and sends its tide of waters against the northwest shore of America. Its effects on that coast are very noticeable; but they are limited, by the geography of that shore, within narrow bounds. In the first place, the passage of Behring’s Strait is too small to permit its waters to have access to the Arctic Sea; then the high ranges of the Cordilleras fence off the interior of the continent, so that the warm winds that blow from the sea cannot penetrate far to the east. Confined to the shore, the heat of the Pacific Gulf Stream generates a large amount of fog; this fog shuts off the sun’s rays, and so lowers the temperature almost as much as the current itself serves to raise it.
The distribution of moisture over the surface of the continent is effected in much the same way as is the distribution of heat. The Gulf Stream gives an abundant rainfall to the States about the Gulf of Mexico lying to the north of that basin; its effects on the rainfall are seen even as far north as the New England States, but they have little effect to the west of the Mississippi River. The high mountains of the Cordilleras cut off the Pacific winds from the centre of the continent, so that very little of the water which flows down to the Gulf of Mexico or to the Atlantic is derived from the Pacific. From the general conditions thus rudely outlined the following arrangement of climates arises. The northern half of the continent is more completely under the dominion of the Arctic Sea than any part of Europe or Asia; the only parts of it fit for the use of civilized man are the northern watershed of the St. Lawrence, the valley of Lake Winnipeg and the Saskatchewan, and the west-coast region as far north as Alaska. The rest of the northern part of the continent is practically barred out from the life of the race by the intensity of the winter cold, and by the brevity of the summer season.
South of this domain of northern cold, North America divides itself, by its climate, soil, and topographical reliefs, into the following fairly distinct regions: (1) The eastern lowlands lying between the shore and the Appalachian range; these shade southwardly into (2) the lowlands of the Gulf States, which is the only part of North America in the immediate control of the Gulf Stream. These Gulf lowlands pass northwardly into (3) the great plain of the Mississippi Valley. Between these lowlands of the centre of the continent and the Atlantic sea-coast lie (4) the table-lands and mountains of the Appalachian system. West of the Mississippi Valley lie (5) the region of the Cordilleras of North America; and finally on the western shore we find (6) a narrow region of low mountains, forming a slender fringe of shorelands.
The mountains of the Appalachian system are composed of two parallel series of elevations, an old eastern range of peaks which are worn down to mere shreds; so that in place of being as high as the Alps, as they once were, they have no peaks that rise seven thousand feet above the sea. This outer range is traceable from Newfoundland to Alabama; but it only rises above six thousand feet in the White Mountains of New Hampshire and the Black Mountains of North Carolina. In form these mountains are steep and rugged. Their steep sides hold the little untillable land that exists east of the Mississippi; their actual area is small, for the chain is very narrow, not exceeding a score or so of miles in width, except in the Carolinas and in the White Mountains, where it is somewhat wider. The total untillable area in this chain does not exceed twelve thousand square miles. West of this, the old Appalachian mountain system, separated from it by a broad, elevated, somewhat mountainous valley, lies the newer Alleghany range. This valley intermediate is one of the most fertile and admirably situated in the world; it extends from New Jersey to Georgia, with an average width of about forty miles and a length of about six hundred, having an area of over twenty thousand square miles. The Alleghany Mountains on the west are composed principally of round, symmetrical ridges, often like gigantic works of art, so uniform are their arches; none of them rise to more than five thousand feet above the sea, and their surfaces are so little broken that they generally afford tillable though as yet generally untilled land. Practically no part of this great range, which extends from near Albany to Alabama, is completely unfit for the uses of man, and it includes some of the most fertile valleys of America. The most important feature connected with this double mountain system of the Appalachians is the great area of table-lands which it upholds; these bordering uplands are found all around the mountain system. The greater part of the States of New York, Pennsylvania, Virginia, West Virginia, the Carolinas, Georgia, Tennessee, Kentucky, and Ohio owe the considerable elevation of their surfaces to the table-land elevations bordering the Appalachian mountain system. Taken altogether, this mountain system is perhaps the finest region for the uses of man that the world affords; its great length, of more than fifteen hundred miles from north to south, gives it a range of climate such as would be had in Europe by a mountain chain extending from Copenhagen to Rome. The total area of this Appalachian district, mountains as well as table-lands, is about three hundred thousand square miles. This is an area equal to near thrice the surface of Great Britain.
The Appalachian table-lands fade gradually into the Mississippi Valley. Their distinct character continues to near the borders of that stream where it unites with the Ohio. As we come upon the table-land system of the Cordilleras, soon after we pass west of the Mississippi, this great valley may be considered as made up of the table-lands of two great mountain systems, with only a relatively small area of alluvial matter between the mouth of the Ohio and the Gulf. Unlike the Ganges, the Amazon, and most other great rivers of the first class, the Mississippi River has a small delta section: not over twenty to thirty thousand square miles has this character. By far the greater part of the basin is really table-land, and is thus free from the evil of low countries to a degree equalled by no other very great river basin. Its valley is characteristically a table-land valley, with a general surface of rolling plain, varying from three hundred to five thousand feet above the level of the sea. Outside of the Cordilleras and the Appalachians, this valley has few mountain folds within its ample space. The absence of included mountain systems is almost as noteworthy a feature as the small amount of delta. There are only two or three patches of mountains that lie far beyond the limits of the great mountain systems of the east and west; and only one of these, the Ozark Mountains of Missouri and Arkansas, is at any distance from the main ranges. This is an insignificant group of low hills having considerable geological but no geographical importance.
On the western border of the Mississippi Valley rise the vast ridges of the Cordilleras. This great mountain region is, next after the mountainous area of Central Asia, the most extensive region of great altitude in the world. From Mexico northward this system of mountains widens, until, in the parallel of forty degrees, it has a width of about one thousand miles. This system is made up of many ridges lying upon an elevated table-land. The valleys of the lesser streams are generally over seven thousand feet above the sea; the main peaks, to the number of many hundred, rise over twelve thousand feet above the sea level; many of them attain to about fourteen thousand feet of altitude. Its table-land extends east to near the Mississippi River. The great height and width of this mountain system produce a very marked effect upon the climate of the vast area that it incloses, and upon the country which lies within a thousand miles to the east of its mountain walls. The winds from the Pacific are to a great extent drained of their moisture in the western or Sierra Nevada section of these mountains, and have little moisture to give to the central and eastern chains; and when these winds emerge on to the western plains, they are as dry as those that blow over the Sahara.
Although these Cordilleras of North America afford access by their dislocations to a great supply of mineral substances, they are on the whole a curse to the continent. By the cold and dryness which their height entails, they reduce one third of the continent to sterility. Though here and there in their valleys we find oases of fertile land, and many regions of limited area may be made fertile by the use of irrigation, at least nineteen-twentieths of their lands are irretrievably barren. When their resources of precious metals are exhausted, as is likely to be the case within a hundred years, they will probably be to a great extent abandoned by man. Only the extreme northern section and a part of the central and border lands afford any other attractions to settlers than is found in their mineral wealth.
West of the Cordilleras of North America we have a narrow and mountainous coast region that is abundantly watered by the moisture from the Pacific, which penetrates some distance into the land over the lower ridges that border on them. Although this belt of fertile country cannot be compared in populationsustaining power with the Atlantic coast region, it is of great fertility, and has a climate of surpassing excellence.
On the borders of Mexico, within the limits of the United States, the mountains sink down to much less extreme heights, and the climate becomes less strenuous. This region is better fitted for the permanent occupation of man; but only a small part of the land is arable,—probably not one-tenth of its surface is or ever will be fit for the plough.
In Mexico proper we have a country that retains the character of the Cordilleras so far as its general elevation is concerned, but loses the lofty ridges which we find farther to the north. The loss of these barriers, combined with the narrowing of the space between the Atlantic and the Pacific waters, and its more southern position, increases the temperature and the rainfall; so that the fertility of the country augments in a rapid way as we go southwards, until finally in the isthmic part of the continent we have a tropical luxuriance of life. The lowland borders of the country gain upon the width of the table-land, until south of the Tehuantepec Isthmus the whole region is essentially unfit for the uses of our race.
The climate of North America south of the divide which separates the streams flowing toward the Arctic Circle from those entering the Atlantic south of Labrador may be said to resemble that of Europe in all important respects. The winters are far colder; but the summer seasons, which determine the usefulness of the soil to man, are as warm and quickening to plants as are those of the Old World. The more considerable cold of winter is a disadvantage, inasmuch as it limits the work of agriculture to a smaller part of the year, and requires a greater expense in the keeping of livestock. This is a considerable evil, especially in the regions north of the parallel of forty degrees; but the cold is not greater than in Northern Germany or in Scotland. There can be no doubt that the body and the mind receive certain advantages from the tonic quality of the winters which compensate for this loss.
Nearly the whole of North America that is within the limits of the United States receives some share of frost. This secures it against the permanent occupation of contagious fevers, which from time to time find their way to it from the tropics.
North America, east of the 100th meridian (west of Greenwich) and north of thirty-five degrees, has a soil which is on the whole superior to that of Europe. Practically the whole of this vast area is tillable, and the variety of crops is very great, considerably greater than that of Europe. West of the 100th meridian the rainfall diminishes rapidly, being especially limited in the summer season. The winters become longer and more extreme throughout all the region within or under the climatic influence of the Cordilleras; the soil is thinner, and over vast regions almost wanting. In certain exceptional tracts as far westward as the Saskatchewan, and at points along the line between the United States and Canada to the south of that valley, there are considerable areas of good soil; but, considered in a general way, we may exclude all the region between the 100th meridian and the Sierra Nevada range from the hope of any great agricultural future. Even should the rainfall be increased by tree-planting in those regions where trees may grow, the quality of the soil in this district, even where soil exists, is often too poor for any use. Yet in some parts it is very good, and if tree-planting should increase the rainfall, some limited areas will be tillable.
Next to the quality of the soil, the forest covering of a country does the most to determine its uses to man. Although the Western prairies have the temporary advantage that they are more readily brought under cultivation than wooded regions, the forests of a land contribute so largely to man’s well-being, that without them he can hardly maintain the structure of his civilization. The distribution of American forests is peculiar. All the Appalachian mountain system and the shore region between that system and the sea, as well as the Gulf border as far west as the Mississippi, were originally covered by the finest forest that has existed in the historical period, outside of the tropics. In the highlands south of Pennsylvania and in the western table-land north to the Great Lakes, this forest was generally of hard-wood or deciduous trees; on the shore-land and north of Pennsylvania in the highlands, the pines and other conifers held a larger share of the surface. The parts of the land bordering the Mississippi on the west, as far as the central regions of Louisiana, Arkansas, and Missouri, are forest clad. Michigan and portions of Wisconsin and Minnesota have broad areas of forests, but the cis-Mississippian States of Indiana and Illinois, and the trans-Mississippian country west to the Sierra Nevada, is only wooded, and that generally scantily, along the borders of the streams. Data for precise statements are yet wanting, but there is no doubt that this area is untimbered over about seven eighths of its surface, and the wood which exists has a relatively small value for constructive purposes. North of the regions described, except along the Pacific coast, where fine soft-wood forests extend from near San Francisco to Alaska, the forest growth rapidly diminishes in size, and therefore in value, the trees becoming short and gnarled, and the kinds of wood inferior. So that the region north of the St. Lawrence and of the Great Lakes is not to be regarded as having any very great value from the forest resources it affords. In estimating the value of North America to man, the limitation of good forests to the region east of the Mississippi must be regarded as a disadvantage which is likely to become more serious with the advance of time. Undoubtedly the timberless character of the prairie country for at least two hundred miles west of the Mississippi is in the main due to the constant burning over of the surface by the aborigines. It seems possible that these regions may yet be made to bear extensive woods. The elevated plains that lie farther to the west seem to have too little rainfall for the support of forests.
The rivers of a country are a result and a measure of its climate. The generally large rainfall of the eastern half of North America is shown by the number and size of its streams, which, area for area, are longer and more frequent than those of the Old World, except on the eastern coast of Asia. The heaviest rainfall and the greatest average of streams is found about the Gulf of Mexico and the southern part of the Appalachian district. Hence, northerly, westerly, and northwesterly, the rainfall decreases in amount. The average of the region east of the Mississippi and south of the Laurentian Mountains is probably about fifty inches per annum, somewhere near one-third more than that of Europe. North America, despite the very dry district of the Cordilleras, has an average rainfall about as great as that of Europe, and probably rather greater than Asia; indeed its water-supply is rather greater than the average for lands situated so far from the equator.
The rivers of America have been of very great importance in the settlement of the land. They afford more navigable waters than all the streams of Asia put together. Without the system of the Mississippi, which has more navigable waters than any river except the Amazons, it would not have been possible for America to have been brought under the control of colonies with such speed.
The elevation of the surface of North America, at least of its more habitable portions, is very favorable to man. A large part of its fertile soils lie from five hundred to fifteen hundred feet above the sea. It has a larger part of its surface within the limits of height that are best suited to the uses of man than Asia, but less than Europe has.
In considering the fitness of this continent for the use of European races, it will not do to overlook the mineral resources of the country. It may be stated in general terms that North America is richer in the mineral substances which have most contributed to the development of man than any other continent. The precious metals may be briefly dismissed. They occur constantly in two areas: the Cordilleran,—which, from Mexico, California, Nevada, New Mexico, and Colorado, has doubtless furnished more gold and silver than any other one mountain district,—and the Appalachian region, which has given about sixty million dollars to the world’s store of gold. The precious mineral resources of the Cordilleran region are probably greater than those of any other continent. They have already exercised a very great influence on the commercial and political history of the continent, and are likely to become of more importance as time goes on, for at least half a century to come.
In the so-called baser, yet really more precious, metals this continent is even more fortunate. The supplies in the most important metal, iron, are very great,—certainly greater than in Europe. This metal is distributed with much uniformity over the country, there being scarcely a State except Florida that cannot claim some share of this metal. Especially rich in deposits of this metal are the States which share the Appalachian district, and the States of Missouri and Michigan. The Rocky Mountains also abound in iron ores, which there often contain a certain proportion of the precious metals; so that it is possible that the exploitation of the two metals may in time be carried on there together. There is probably no other continent that contains as large a share of iron,—the most important metal for the uses of man.
The other less used, but still commercially important, metals,—zinc, lead, and copper,—are found in considerable abundance in the Appalachian, the Laurentian, and the Cordilleran regions, especially in the last-named district. The only metal that is rarely found in North America, never yet in quantities of economic importance, is tin. Some specimens of bronze implements have been found in Mexico and Peru. They seem to afford the only evidence that the aboriginal peoples knew how to smelt any metals. Though the natives in the more northern districts used copper, they never discovered the art of smelting it.
Considering the useful metals as a whole, North America is proportionally richer than any other country that is well known to us.
The most considerable of the resources that the rocks of America offer, are found in the deposits of coal which they contain. These deposits are of vast extent, and are excellently fitted for the various uses of this fuel. While the other mineral resources of the country are most abundant in the region of the Cordilleras, the best of these deposits of coal are accumulated in and about the Appalachian district. At least nine tenths of the coal of America lies to the east of the Mississippi River. New England, New York, South Carolina, Florida, Mississippi, and Louisiana are the only States that are practically without coal; and even in New England, Rhode Island and the neighboring parts of Massachusetts have promising but essentially undeveloped fields. In the Cordilleran district coal deposits of small area occur; but the material is generally of poor quality, and is not likely to have a great utility.
As a whole, the resources in the way of subterranean fuel are far richer on this continent than in Europe. The area of coal-bearing rocks is at least eight times as great, and the deposits are much better disposed for working. No other continent save Asia is likely to develop anything like these coal resources; in China the coal area seems much larger than that of North America, but the richness of the field has not yet been fully proven: it is, however, undoubtedly great.
As the latent power of any modern society depends in an intimate way upon the buried stores of solar energy in coal-beds, the large area and good quality of the American coal-fields are very important advantages, and are full of promise for the economic future of its people.
Among the less important resources of the rocks in North America are the various classes of coal-oils which were first brought into commerce from its fields. Although these oils are not peculiar to North America, the small amount of disruption which its rocks have undergone have caused them to be retained in the subterranean store-houses; while in other countries, where the rocks have been more disturbed, these oils have been allowed to escape to the streams or the air. The areas where these oils occur on the continent are widely scattered. They are, however, principally confined to the Upper Ohio Valley; they are known to exist also in the Valley of the Cumberland River, in California, and in Western Canada north of Lake Erie. Besides these flowing oils there are immense areas of black shales, which yield large quantities of oil to distillation. These are not now of value, on account of the abundance of these flowing oils; but as in the immediate future these flowing wells are likely to cease their production, we may look to these shales for an almost indefinite supply of oil. In the Ohio Valley, extending eastward in Virginia into the valleys of the Atlantic streams, there is an area of over one hundred thousand square miles of this shale, which is on the average over one hundred and fifty feet thick, and yields about ten per cent of oil. In other words, it is equal to a lake of oil as large as New York and Pennsylvania, and fifteen feet deep,—a practically unlimited source of this material.
It is important to note that the sources of supply of phosphate and alkaline marls are very large. As these substances are subject to a constant waste in agriculture, and are the most important of all materials to the growth of the standard crops, the soil of America promises on the whole to be as enduring as is that of Europe, though, owing to the larger rainfall, it tends to waste away more rapidly.
The building stones of a country are of importance, inasmuch as they affect the constructions of a people; in such materials, suited for the purposes of simple strength and durability, the country is very well supplied, being quite as well off as Europe. On the other hand, the stones that lend themselves to the more decorative uses, the pure white or variegated marbles, are not nearly as rich as the countries about the Mediterranean, which is of all known regions the richest in decorative stones.
It is not possible within the limits of this chapter to support by sufficient details the foregoing statements concerning the physical conditions of America. The necessary brevity of the work has made it difficult to find place for all the points that should be presented; it may be fairly said, however, that the statements as made are to a very great extent matters of general information, which lie beyond the scope of debate, being well known to all students of American physiography.
Accepting the foregoing statements as true, it may be fairly owned that the general physical conditions of the American continent closely resemble those of Europe, and that in all the more important matters our race gained rather than lost by its transfer from the Old World to the New.
