Black Africa, as I have said, lies south of the Sahara Desert. Here the negro has dwelt for unnumbered ages. The key-note of black history, like yellow history, has been isolation. Cut off from the Mediterranean by the desert which he had no means of crossing, and bounded elsewhere by oceans which he had no skill in navigating, the black man vegetated in savage obscurity, his habitat being well named the "Dark Continent." Until the white tide began breaking on its sea-fronts four centuries ago, the black world's only external stimuli had come from brown men landing on its eastern coasts or ascending the valley of the Nile. As time passed, both brown and white pressures became more intense, albeit the browns long led in the process of penetration. Advancing from the east and trickling across the desert from the north, Arab or Arabized adventurers conquered black Africa to the equator; and this political subjugation had also a racial side, for the conquerors sowed their blood freely and set a brownish stamp on many regions. As for the whites, they long remained mere birds of passage. Half a century ago they possessed little more than trading-posts along the littorals, their only real settlement lying in the extreme south. Then, suddenly, all was changed. In the closing decades of the nineteenth century, Europe turned its gaze full upon the Dark Continent, and within a generation Africa was partitioned between the European Powers. Negro and Arab alike fell under European domination. Only minute Liberia and remote Abyssinia retained a qualified independence. Furthermore, white settlement also made distinct progress. The tropical bulk of Africa defied white colonization, but the continent's northern and southern extremities were climatically "white man's country." Accordingly, there are to-day nearly a million whites settled along the Algerian and Tunisian seaboard, while in South Africa, Dutch and British blood has built up a powerful commonwealth containing fully one and one-half million white souls. In Africa, unlike Asia, the European has taken root, and has thus gained at least local tenures of a fundamental nature. The crux of the African problem therefore resolves itself into the question whether the white man, through consolidated racial holds north and south, will be able to perpetuate his present political control over the intermediate continental mass which climate debars him from populating. This is a matter of great importance, for Africa is a land of enormous potential wealth, the natural source of Europe's tropical raw materials and foodstuffs. Whether Europe is to retain possession depends, in the last analysis, on the character of the inhabitants. It is, then, to the nature of the black man and his connection with the brown world that we must direct our attention.