The productive capacity of a country is, however, in one respect very different from those great physical features—such as temperature, rainfall, coast configuration, surface character, geological structure, and river system—which have been previously noted. Those features are permanent qualities which man can affect only to a limited extent, as when he reduces the rainfall a little by cutting down forests, or increases it by planting them, or as when he unites an isle, like that of Cadiz, to the mainland, cuts through an isthmus, like that of Corinth, or clears away the bar at a river mouth, as that of the Mississippi has been cleared.
Exhausting the Mineral Wealth
But the natural products of a country may be exhausted and even the productive capacity of its soil diminished. Constant tillage, especially if the same crop be raised and no manure added, will wear out the richest soils. This has already happened in parts of Western America. Still the earth is there; and with rest and artificial help it will recover its strength. But timber destroyed cannot always be induced to grow again, or at least not so as to equal the vigour of primeval forests. Wild animals, once extirpated, are gone for ever. The buffalo and beaver of North America, the beautiful lynxes of South Africa and some of its large ruminants, are irrecoverably lost for the purposes of human use, just as much as the dinornis, though a few individuals may be kept alive as specimens. So, too, the mineral resources of a country are not only consumable, but obviously irreplaceable. Already some of the smaller coalfields of Europe have been worked out, while in others it has become necessary to sink much deeper shafts, at an increasing cost. There is not much tin left in Cornwall, not much gold in the gravel deposits of Northern California. The richest known goldfield of the world, that of the Transvaal Witwatersrand, can hardly last more than thirty or forty years. Thus in a few centuries the productive capacity of many regions may have become quite different from what it is now, with grave consequences to their inhabitants.
These are some of the ways in which Nature affects those economic, social, and political conditions of the life of man the changes in which make up history. As we have seen, that which Nature gives to man is always the same, in so far as Nature herself is always the same—an expression which is more popular than accurate, for Nature herself—that is to say, not the laws of Nature, but the physical environment of man on this planet—is in reality always changing. It is true that this environment changes so slowly that a thousand years may be too short a period in which man can note and record some forms of change—such, for instance, as that by which the temperature of Europe became colder during the approach of the glacial period and warmer during its recession—while ten thousand years may be too short to note any diminution in the heat which the sun pours upon the earth, or in the store of oxygen which the earth’s atmosphere holds.
Progress of Modern Invention
But as we have also seen, the relation to man of Nature’s gifts differs from age to age as man himself becomes different, and as his power of using these gifts increases, or his need of them becomes either less or greater. Every invention alters those relations. Water power became less relatively valuable when steam was applied to the generation of motive force. It has become more valuable with the new applications of electricity. With the discovery of mineral dyes, indigo and cochineal are now less wanted than they were. With the invention of the pneumatic tyre for bicycles and carriages, caoutchouc is more wanted. Mountains have become, since the making of railways, less of an obstacle to trade than they were, and they have also become more available as health resorts. Political circumstances may interfere with the ordinary and normal action of natural phenomena. A race may be attracted to or driven into a region for which it is not physically suited, as Europeans have gone to the West Indies, and negroes were once carried into New York and Pennsylvania. The course of trade which Nature prescribes between different countries may be hampered or stopped by protective tariffs; but in these cases Nature usually takes her eventual revenges. They are instances which show, not that man can disregard her, but that when he does so, he does so to his own loss.
It would be easy to add further illustrations, but those already given are sufficient to indicate how multiform and pervading is the action upon man of the physical environment, or in other words, how in all countries, and at all times, geography is the necessary foundation of history, so that neither the course of a nation’s growth, nor its relations with other nations, can be grasped by one who has not come to understand the climate, surface, and products of the country wherein that nation dwells.
There is no Unmixed Race left
This conception of the relation of geography to history is, as has been said, the leading idea of the present work, and has furnished the main lines which it follows. It deals with history in the light of physical environment. Its ground plan, so to speak, is primarily geographical, and secondarily chronological. But there is one difficulty in the way of such a scheme, and of the use of such a ground plan, which cannot be passed over. That difficulty is suggested by the fact already noted—that hardly any considerable race, and possibly no great nation, now inhabits the particular part of the earth’s surface on which it was dwelling when a history begins. Nearly every people has either migrated bodily from one region to another, or has received such large infusions of immigrants from other regions as to have become practically a new people. Hence it is rare to find any nation now living under the physical conditions which originally moulded its character, or the character of some at least of its component elements. And hence it follows that when we study the qualities, aptitudes, and institutions of a nation in connection with the land it inhabits, we must always have regard not merely to the features of that land, but also to those of the land which was its earlier dwelling-place. Obviously, this brings a disturbing element into the study of the relations between land and people, and makes the whole problem a far more complicated one than it appeared at first sight.