nineteenth century, travel, previously a pastime of the rich, was brought within the reach of very moderate purses. This democratisation of travel is still going on, and in certain recent visits of British working men to Germany and elsewhere we may perhaps see the beginning of a process which will eventually bring some amount of journeying abroad within the reach of all.

As yet the effect upon geography of this increase in travelling has been chiefly to enhance popular interest in the science, rather than to enrich it, for the vast majority of “popular” travel books have added little, if anything, to the sum total of knowledge. But this is partly because geographical teaching has hitherto been badly organised, and the greater number of travellers have started on their journeys without having been taught what to observe or how to observe. There are already indications that this condition of affairs is passing away, and that the traveller of the future will start better equipped, and will demand in his guide-books a new point of view. Starting from a higher level he will bring back more from his travels.

Meantime it should be noted that some knowledge of the generalisations laid down by geographers during the course of the last half century adds enormously to the interest of travel, both at home and abroad, and that for this reason, if for no other, geography is worth study by all.

In the following chapters we shall look, so far as possible, at those aspects of the subject which make the widest appeal, and which are best fitted to enable the ordinary man to understand his surroundings, whatever they may be, and so aid him in that delicate task of adjustment which, consciously or unconsciously, is the task of every living thing. As limitations of space involve a similar limitation of subject-matter, it has been thought best to lay most stress upon the conditions which prevail in Europe and North America, the areas which have been most thoroughly studied. Europe has the special interest that it has given origin to the type of civilisation which has most profoundly modified the earth’s surface. This limitation cannot, however, be made rigid, for it is of the essence of the modern standpoint that no area can be understood without reference to the world at large. The geography of Europe no less than of North America is determined by the position of the respective continents on the surface of the globe, and cannot be understood without a consideration of this position and its implications. The standpoint adopted here is frankly anthropological, that is, the world is considered as the home of man, its physical peculiarities being regarded as interesting chiefly in their relation to man and his activities.

Finally, we may note that the development of the subject within recent years has been such that it is quite impossible, even within the limitations already laid down, to give a complete survey of the subject. All that will be attempted, therefore, is to suggest some of the lines along which research is proceeding most actively at the present time, special stress being laid upon those aspects of the subject which are not as yet fully treated in the smaller text-books. The list of books of reference at the end will, it is hoped, enable those interested to fill in the blanks which such a scheme necessarily leaves.

CHAPTER II

SURFACE-RELIEF AND THE PROCESS OF EROSION

It is not necessary here to consider the various formal definitions of geography which have been proposed in the last few years. As is only natural with a developing subject, much discussion has taken place as to the exact limits of its field of action, and many definitions have been proposed with the object of setting forth these limits as clearly as possible. But it is sufficient for our purpose to note that geography deals with the surface-relief of the earth, and with the influence which that relief exercises upon the distribution of other phenomena, and especially upon the life of man. Before we proceed to study detailed problems, then, it is obviously necessary to look at some general points connected with the relief of the earth’s surface and its causes.

In the words of the physical geographer, the earth’s surface consists of the solid crust, or lithosphere, of the mass of water forming the seas and oceans and constituting the hydrosphere, and of that envelope of gas which we call the atmosphere. Considered separately, each of these is the concern of special sciences, and not of the geographer proper. His business it is to take the facts furnished by the meteorologists, the physicists, the geologists, and so forth, and with these facts in hand to proceed to consider the effect of the interaction of earth and water and air in a way which the separate sciences cannot do. We must further note that it is the interactions of these three which make the earth a possible home for life as we know it, and it is these interactions therefore which influence the distribution of life on the surface of the globe.

There may have been a period when the crust of the earth was clothed in a uniform sheet of water, just as the globe is now enveloped in a complete covering of air, but at present, as through the long ages of geological time, the lithosphere consists of elevations and hollows, and it is in the hollows that the water accumulates, so that we can distinguish between the dry land and the ocean beds. Both chemically and physically the fluid hydrosphere differs markedly from the solid lithosphere, and it is, above all, the physical differences which are of supreme importance to the geographer. Because of them sea and land respond differently to the stream of solar energy which pours down upon our globe, and it is this different response which is the predominating factor in the production of the different climates, which again determine in its main outlines the distribution of living organisms.

This being so, it is clear that it is of great importance to the geographer to know exactly the distribution of land and water over the surface of the earth. As the North Polar regions are still inadequately known, and the South Polar regions hardly known at all, we cannot as yet determine exactly this distribution, but any globe will show that land and ocean are very unequally distributed. The great land masses cluster round the North Pole, while the southern hemisphere consists largely of water. We thus have a land hemisphere and a water one. According to recent calculations the oceans occupy some 72 per cent. of the entire surface of the globe, leaving only 28 per cent. of land. But while in the northern hemisphere there is about one and a half times more water than land, in the southern there is about six times more water, both figures being liable to error, as indicated above, owing to our uncertainty as to the land and water of the Polar zones.

This distribution is of great importance in connection with certain theories as to the actual plan of the earth, but this is a difficult subject which need not concern us here. It is discussed in Prof. J. W. Gregory’s volume on The Making of the Earth. More interesting is the effect which the arrangement of land and water has had upon that part of the life of the earth which was evolved in late geological time. Though the geographer for convenience’ sake recognizes three separate continents in the Old