class="x-ebookmaker-pageno" title="[9]" id="pgepubid00012"/> and interest, but in the stress which he laid upon the earth as above all interesting in that it is the field of the activity of man, he emphasised an aspect of the subject in which perhaps the most interesting modern developments have taken place.

Darwin had a twofold effect upon the progress of geography. In the first place, in his detailed work, e. g. in connection with coral reefs, and with the distribution of animals, and less directly in his investigation of the part played by earthworms in the formation of soil, he himself added to geographical knowledge. But he did much more than this. The doctrine of evolution which he made common property has had and is having an enormous effect upon geographical science, both directly and indirectly.

As is well known, in connection with his own theory of the cause of evolution, Darwin laid great stress upon the “Struggle for Existence.” But he himself expressly stated that he used the term in a “large and metaphorical sense,” a sense which in popular language it has tended to lose. From the geographer’s standpoint, therefore, it is better to say that Darwin’s work has added a new interest to the study of interrelations. Humboldt, as we have indicated, was greatly interested in such subjects as the connection between the climate of a region and the vegetation, between the activities of man in a particular region and the physical conditions, and so on. But Darwin added a new interest to such studies. For example, it is a curious fact that desert plants have often spiny leaves, long roots, and so forth, and it is interesting to note how these peculiarities fit the plants for life in an arid climate. But when Darwin showed that there was evidence that the physical conditions of the desert gave rise to certain types of vegetation, it became worth while to study both the physical conditions and the characters of the plants in much greater detail than before.

If we simply lay it down as an axiom that, e. g. cactuses live in deserts, the fact has only a moderate interest, but when we find that almost any natural group of plants, if exposed through long ages to gradually increasing conditions of drought, will produce “cactus” types, then the whole subject acquires new importance. This illustration may serve to suggest what Darwin has done for geography.

He showed that there is a delicately adjusted balance between organisms and their surroundings, taken in their widest sense. But geology proves that through the ages there have been constant, if slight, changes in the physical conditions, and the effort of the organisms to readjust the balance thus disturbed has led to evolution. Thus to some extent at least the characters of organisms can be explained by the nature of their surroundings. A further interest is added by the fact that in this respect human societies and settlements can be shown to behave like organisms. Therefore we can hope to explain at least partially the manifold differences in man and his societies in different parts of the globe by the minor differences in physical conditions. In other words, the doctrine of evolution has added a unifying and co-ordinating principle which has not only prevented geography from being crushed by the enormous recent increase in known facts, but has also for the first time raised it to the level of a science.

This addition of a co-ordinating principle may be said to be the direct effect of the publication of the Origin of Species, but there has been an indirect effect almost as important. The principles enunciated in that book had a stimulating effect, not upon one science only but upon every department of thought. Phenomena of no importance suddenly became interesting, and the result of this interest was an enormous addition to known facts. Not only has research been stimulated in every direction, but as this research has been largely directed by the desire to discover the interrelation of phenomena, we find that many of the old barriers between the sciences are breaking down.

The botanists are no longer content to study the facts of plant distribution; they now want to be able to give reasons for particular distributions. Therefore they must seek the aid of the meteorologists to explain differences of climate; of the physical geographer to make clear the effects of relief, of differences of soil, and of drainage; of the cartographer to represent the facts which emerge from their surveys, and so on. The physician must now seek the assistance of the zoologist before he can deal adequately with tropical disease, and the zoologist must have the help of the physical geographer before he can give adequate aid. The result is that in all directions geography is being enriched by facts brought from the collateral sciences, while at the same time its position as a central unifying science is becoming more and more established; as a science which can deal with all these varied facts, but deal with them from a standpoint peculiarly its own.

At the present time, geography may be compared to one of Rodin’s statues in which we see a beautiful figure as it were struggling to escape from the marble in which it is imprisoned. So the geography of to-day is in the act of escaping from the matrix of mere facts in which it has been too long imprisoned. It is now displaying itself as a great unity in the making of which all the sciences have played their part.

But even in this general survey of recent developments two other sets of facts must be touched upon. We have given fifty years as the period within which most of what is distinctively modern in geography has developed. It must not be forgotten that within the same period there has been a remarkable renewal of interest in geographical exploration. Roughly speaking, within this period Africa has ceased to be an unknown continent; the innermost recesses of Asia have been largely explored; the Arctic and Antarctic areas have yielded many, though by no means the whole, of their secrets; a great deal of exploration has been done in America as a whole, as well as much detailed survey work in the United States and Canada; the oceans have been investigated by successive series of expeditions. Generally it may be said that in its broad outlines our knowledge of the world has been completed, so that geographical science is free to pass from the mere collection of raw material to the higher task of arranging, classifying, and making deductions, as well as to the more detailed surveys which are still necessary.

The other point of interest is that the last fifty years have seen an enormous increase in the facilities for travel, a fact which has led to a great increase in the number of people to whom geography appeals. The decade between 1830 and 1840 saw the beginning of two great series of guide-books, Murray’s Handbooks and Baedeker’s Guides, whose importance for the travelling public can hardly be over-estimated. The first “Baedeker” was a little guide to the Rhine, and since it was first published this firm of publishers has not only extended its field of operations over nearly the whole world, but has issued a constant stream of new editions, which for the most frequented tourist regions are practically annual. That great tourist agency whose name is now a household word began operations in the early forties, and like the firm of Baedeker has now taken the world as its sphere of action. We may say, then, that during the course of the