Meanwhile two explorers, Captain (afterwards Sir Richard) Burton and Captain Speke, had started from Zanzibar to discover a lake of which rumours had for a long time been heard, and in the following year succeeded in reaching Lake Tanganyika. On their return Speke parted from Burton and took a route more to the north, from which he saw another great lake, which afterwards turned out to be the Victoria Nyanza. In 1860, with another companion (Captain Grant), Speke returned to the Victoria Nyanza, and traced out its course. On the north of it they found a great river trending to the north, which they followed as far as Gondokoro. Here they found Mr. (afterwards Sir Samuel) Baker, who had travelled up the White Nile to investigate its source, which they thus proved to be in the Lake Victoria Nyanza. Baker continued his search, and succeeded in showing that another source of the Nile was to be found in a smaller lake to the west, which he named Albert Nyanza. Thus these three Englishmen had combined to solve the long-sought problem of the sources of the Nile. The discoveries of the Englishmen were soon followed up by important political action by the Khedive of Egypt, Ismail Pasha, who claimed the whole course of the Nile as part of his dominions, and established stations all along it. This, of course, led to full information about the basin of the Nile being acquired for geographical purposes, and, under Sir Samuel Baker and Colonel Gordon, civilisation was for a time in possession of the Nile from its source to its mouth. Meanwhile Livingstone had set himself to solve the problem of the great Lake Tanganyika, and started on his last journey in 1865 for that purpose. He discovered Lakes Moero and Bangweolo, and the river Nyangoue, also known as Lualaba. So much interest had been aroused by Livingstone's previous exploits of discovery, that when nothing had been heard of him for some time, in 1869 Mr. H. M. Stanley was sent by the proprietors of the _New York Herald_, for whom he had previously acted as war-correspondent, to find Livingstone. He started in 1871 from Zanzibar, and before the end of the year had come across a white man in the heart of the Dark Continent, and greeted him with the historic query, "Dr. Livingstone, I presume?" Two years later Livingstone died, a martyr to geographical and missionary enthusiasm. His work was taken up by Mr. Stanley, who in 1876 was again despatched to continue Livingstone's work, and succeeded in crossing the Dark Continent from Zanzibar to the mouth of the Congo, the whole course of which he traced, proving that the Lualaba or Nyangoue were merely different names or affluents of this mighty stream. Stanley's remarkable journey completed the rough outline of African geography by defining the course of the fourth great river of the continent.