Down to the time of the French Revolution, Europe had hardly dared to cast a covetous eye on the interior of Africa. Portugal, Eng land and France held sway at a few stations along the coast. The sturdy Boers, near the Cape of Good Hope, alone represented actual colonization by Europeans. The Revolution brought in its train Bonaparte's conquest of Egypt, the first great onslaught on African territory on the part of Christendom in mod ern times. The consequences of the French domination, brief as it was, were far-reaching in the loosening of Turkey's hold upon that country. Another result of the wars of the revolution was the supplanting of Dutch do minion at the Cape by that of England. An army of ardent missionaries now made their way into the interior of South Africa. While England was laying the foundations of an empire at this end of Africa, France suddenly invaded north and conquered Algeria (1830-48). A few years before this invasion, Mehemet Ali, viceroy of Egypt, brought Nubia and Kordofan under his sway. This ambitious potentate, who, for the first time since the days of Saladin, made the aggressive power of Africa felt in another continent, in his role of modernizer of Egypt, sent various scientific expeditions to explore the Nile, which was now traced almost to the equator. To this period of African exploration belong the travels of Riippell, the brothers Abbadie, Beke and Krapf in Abyssinia.
With the middle of the 19th century com menced an extraordinary era in the history of geographical discovery. The world began to close in upon the dark interior of Africa, and in the course of a generation the great features of the continent were unfolded almost in their entirety. In 1847 the German missionaries Krapf and Rebmann discovered the snow capped peaks of Kilima-Njaro and Kenia, near the equator. In 1849 Livingstone discovered Lake Ngami, in the heart of South Africa, at a distance of 1,000 miles from Cape Town. In the course of the next seven years he extended his explorations to the Upper Zambesi, of which mighty stream hardly anything had hitherto been known, followed it up, struck out west along the edge of the Kongo basin (a circumstance unknown to him), made his way to the Portuguese possessions on the At lantic, then, turning back, followed the Zam besi down stream, discovered the Victoria Falls, the rival of Niagara, and came to the shores of the Indian Ocean. While Livingstone was drawing a luminous trail across South Africa from sea to sea, Heinrich. Barth was lifting the veil from the depths of the continent on the other side of the equator by his extraordinary journeys in the-west half of the Sudan. In the sixth and seventh decades of the century large accessions were made to the knowledge of the Nile basin and the surrounding regions, includ ing Abyssinia, by the travels of Petherick (who explored the basin of the Bahr-el-Gazal), Mun zinger, Beurmann, Heuglin, and others. In the meanwhile the French were pushing into West Africa on the side of Senegambia, Du Chaillu traveled in the country back of the Gabun and through the wilds of the Ogowe, the home of the gorilla and the pygmy Obongo; Burton scaled the peak of Kamerun, and Von der Decken explored what is now British East Africa.
Just as Barth was emerging from the scorching suns of Central Africa, laden with the knowledge of countless peoples, in another con tinent three equally intrepid Germans proceeded to explore the most elevated region of the globe. The brothers Schlagintweit crossed the Himalayas and the Karakoram, traversed the lofty plateau of Tibet and surmounted the Kuenlun, reaching heights to which no traveler had ever climbed.
Soon after Livingstone's traverse of South Africa, the beginning was made of those dis coveries which unraveled the most interesting problem presented by the geography of that continent. In 1858 Burton and Speke, dis patched by the Royal Geographical Society in quest of a great reservoir of fresh water which was believed to exist somewhere in the region whence the Nile issued, discovered Lake Tan ganyika. Before the close of that year, Speke discovered a still larger lake, the Ukerewe, or Victoria Nyanza, which he assumed to be a reservoir of the Nile, though as yet its outlet remained to be found. To what river system, if any, Lake Tanganyika belonged was a prob lem which was to wait still many years for a final solution. In 1859 Livingstone came to the shores of a third great lake, the Nyassa, a feeder of the Zambesi. Within the next five years the question of the sources of the Nile was approximately settled by the explorations of Speke, Grant and Baker. The last named, ascending the river from Egypt in 1864, dis covered the lowest of the Nile reservoirs, the Mwutan Nzige, or Albert Nyanza. What Ptolemy had laid down on his famous map 1,700 years before was found to be substan tially correct, and the discovery later on of snow-clad mountains near the Albert Nyanza, culminating in Ruwenzori, substantiated what the Greek had taught regarding the Mountains of the Moon.
The problem of the Nile was closely inter woven with that of the Kongo, the greatest mystery that still confronted geographers out side of those presented by the polar regions. The Nile question. indeed, could not be re garded as completely settled till the watershed between the two rivers had been determined. Of the Kongo basin, equal in extent to that of the Mississippi, but a mere fraction was known to the world. A boundless maze of tropical forests and rivers had thus far escaped the eye of Europeans. Geographers were not even agreed as to whether the Kongo issued from the heart of the continent or whether it was not rather in the nature of a coast river. Livingstone applied himself with heroic resolu tion to the task of ascertaining the parting of the waters that found their way to the Mediter ranean and those that flowed toward the At lantic. In 1867-68 he discovered the Luapula, the east headstream of the Kongo, and its two large reservoirs, Mweru and Bangweolo, and in 1871 stood on the banks of the great river that hurries past Nyangwe, but not possessed of the information that would assure him be yond doubt that it could be no other than the Kongo.