Thus for six or seven thousand years after man achieved civilization there was rhythmic progress in many lines, but there came no great epochal invention to usher in a new ethnic period. Then, towards the close of what historians of to-day are accustomed to call the middle ages, there appeared in rapid sequence three or four inventions and a great scientific discovery that, taken together, were destined to change the entire aspect of European civilization. The inventions were gunpowder, the mariner's compass, paper and the printing-press, three of which appear to have been brought into Europe by the Moors, whether or not they originated in the remote East. The scientific discovery which must be coupled with these inventions was the Copernican demonstration that the sun and not the earth is the centre of our planetary system. The generations of men that found themselves (1) confronted with the revolutionary conception of the universe given by the Copernican theory; (2) supplied with the new means of warfare provided by gunpowder; (3) equipped with an undreamed-of guide across the waters of the earth; and (4) enabled to promulgate knowledge with unexampled speed and cheapness through the aid of paper and printing-press--such generations of men might well be said to have entered upon a new ethnic period. The transition in their mode of thought and in their methods of practical life was as great as can be supposed to have resulted, in an early generation, from the introduction of iron, or in a yet earlier from the invention of the bow and arrow. So the Europeans of about the 15th century of the Christian era may be said to have entered upon the Second or Middle Status of civilization.
The new period was destined to be a brief one. It had compassed only about four hundred years when, towards the close of the 18th century, James Watt gave to the world the perfected steam-engine. Almost contemporaneously Arkwright and Hargreaves developed revolutionary processes of spinning and weaving by machinery. Meantime James Hutton and William Smith and their successors on the one hand, and Erasmus Darwin, François Lamarck, and (a half-century later) Charles Darwin on the other, turned men's ideas topsy-turvy by demonstrating that the world as the abiding-place of animals and man is enormously old, and that man himself instead of deteriorating from a single perfect pair six thousand years removed, has ascended from bestiality through a slow process of evolution extending over hundreds of centuries. The revolution in practical life and in the mental life of our race that followed these inventions and this new presentation of truth probably exceeded in suddenness and in its far-reaching effects the metamorphosis effected at any previous transition from one ethnic period to another. The men of the 19th century, living now in the period that may be termed the Upper Status of civilization, saw such changes effected in the practical affairs of their everyday lives as had not been wrought before during the entire historical period. Their fathers had travelled in vehicles drawn by horses, quite as their remoter ancestors had done since the time of higher barbarism. It may be doubted whether there existed in the world in the year 1800 a postal service that could compare in speed and efficiency with the express service of the Romans of the time of Caesar; far less was there a telegraph service that could compare with that of the ancient Persians. Nor was there a ship sailing the seas that a Phoenician trireme might not have overhauled. But now within the lifetime of a single man the world was covered with a network of steel rails on which locomotives drew gigantic vehicles, laden with passengers at an hourly speed almost equalling Caesar's best journey of a day; over the land and under the seas were stretched wires along which messages coursed from continent to continent literally with the speed of lightning; and the waters of the earth were made to teem with gigantic craft propelled without sail or oar at a speed which the Phoenician captain of three thousand years ago and the English captain of the 18th century would alike have held incredible.