Page:Popular Science Monthly Volume 53.djvu/118

106 of western civilization. No one can predict what the end of this movement may be.

Without going into detail concerning the fluctuations seen in general history, we may consider those that have taken place in the interior development of particular countries. In France, once busy centers have declined, and their glory has been transferred to other places where conditions have in some way become more advantageous.

In the United States, a country as of yesterday, the fluctuations are sometimes very remarkable. A new region is opened to cultivation; a new lode is discovered; and railroads are built and cities rise as if by magic; then the railroad is extended, the mine is exhausted, or more fertile lands are discovered, and the new city disappears while another one is built somewhere else; but if the favorable conditions continue or others are found or made, it becomes permanent.

In England, the ancient towns which owed their prominence to military, ecclesiastical, or feudal conditions are declining or stationary, while places only recently of relative insignificance have become immense manufacturing centers or commercial cities.

There is no region which we can say will never be of importance; no country that can be supposed superior to a reverse of fortune. The most arid desert will become populous if a gold mine or a diamond bed is discovered in it; the most prosperous country would be liable to decline if a more important source of wealth were found near it. Suppose a method were discovered of applying the heat of the sun directly to the production of motion. Coal would become useless and coal lands waste. If a system of irrigation by artesian wells were practically developed and conveniently applied in the Great Desert, it would become populous. The future of any country is at the mercy of the discovery or of a new application by man of some property of matter. What seems to be a speculative research may possibly result in overthrowing the material or moral equilibrium of the world.

But while the evolution of the earth is going on slowly, almost imperceptibly to man, it is advancing all the time; and while man's evolution is, as we have seen, vastly more rapid to appearance, it has limitations. Man can never burst the bonds that subject him to Nature, and will never be able to abstract himself from the material necessities of his existence. Great as seem to be the resources now at his disposal, his development is absolutely controlled by the conditions of animal life. The earth is already far advanced on its course from the primitive nebulous condition toward that which has been reached by the moon. It, too, like the moon, will eventually lose its interior