This, after all, was but natural. Not only had the white advance been continuous, but its tempo had been ever increasing. The nineteenth century, in particular, witnessed an unprecedented outburst of white activity. We have already surveyed white territorial gains, both as to area of settlement and sphere of political control. But along many other lines white expansion was equally remarkable. White race-increase--the basis of all else--was truly phenomenal. In the year 1500 the white race (then confined to Europe) could not have numbered more than 70,000,000. In 1800 the population of Europe was 150,000,000, while the whites living outside Europe numbered over 10,000,000. The white race had thus a trifle more than doubled its numbers in three centuries. But in the year 1900 the population of Europe was nearly 450,000,000, while the extra-European whites numbered fully 100,000,000. Thus the whites had increased threefold in the European homeland, while in the new areas of settlement outside Europe they had increased tenfold. The total number of whites at the end of the nineteenth century was thus nearly 550,000,000--a gain in numbers of almost 400,000,000, or over 400 per cent. This spelled an increase six times as great as that of the preceding three centuries. White race-growth is most strikingly exemplified by the increase of its most expansive and successful branch--the Anglo-Saxons. In 1480, as already seen, the population of England proper was not much over 2,000,000. Of course this figure was abnormally low even for mediæval times, it being due to the terrible vital losses of the Wars of the Roses, then drawing to a close. A century later, under Elizabeth, the population of England had risen to 4,000,000. In 1900 the population of England was 31,000,000, and in 1910 it was 35,000,000, the population of the British Isles at the latter date being 45,500,000. But in the intervening centuries British blood had migrated to the ends of the earth, so that the total number of Anglo-Saxons in the world to-day cannot be much less than 100,000,000. This figure includes Scotch and Scotch-Irish strains (which are of course identical with English in the Anglo-Saxon sense), and adopts the current estimate that some 50,000,000 of people in the United States are predominantly of Anglo-Saxon origin. Thus, in four centuries, the Anglo-Saxons multiplied between forty and fifty fold. The prodigious increase of the white race during the nineteenth century was due not only to territorial expansion but even more to those astounding triumphs of science and invention which gave the race unprecedented mastery over the resources of nature. This material advance is usually known as the "industrial revolution." The industrial revolution began in the later decades of the eighteenth century, but it matured during the first half of the nineteenth century, when it swiftly and utterly transformed the face of things.