In the year 1866 Livingstone was again in Africa. We find him at the mouth of the Rovuma, a river which enters the sea to the east of Lake Nyassa. He had thirty-seven servants, many of them from India, and one of his men, Musa, had been with him before. He crossed the country to Lake Nyassa, but when he wished to pass over to the eastern shore in native boats, he was stopped by the Arabs, who knew that he was the most formidable opponent of the slave-trade. He had no choice but to go round the lake on foot, and little by little he made contributions to human knowledge, drew maps, and made notes and collections. He came to districts he already knew, where black women were carried off by crocodiles on the bank of the Shire River, where he had lost his wife, and where all the missionaries sent out on his recommendation had died of fever. His staff of servants soon proved to be a worthless lot. The Indians were dismissed, and few of the others could be depended on. The best were Susi and Chuma, who by their faithfulness gained a great reputation both in Africa and Europe. Musa, on the contrary, was a scoundrel. He heard from an Arab slave-dealer that all the country through which Livingstone was about to travel was inhabited by a war-like tribe, who had lately fallen upon a party of forty-four Arabs and killed all but the narrator himself. Musa and most of his comrades were so frightened that they ran away. On his arrival at Zanzibar, Musa informed the British Consul that Livingstone had been attacked and murdered and all his goods plundered. The false account was so cleverly concocted and so thoroughly rehearsed that Musa could not be convicted of deceit. Every one believed him, and the English newspapers contained whole columns of reminiscences of the deceased. Only one friend of Livingstone, who had accompanied him on one of his journeys and knew Musa, had any doubts. He went himself to Africa, followed Livingstone's trail, and learned from the natives that the missionary had never been attacked as reported, but that he was on his way to Lake Tanganyika. The road thither was long and troublesome, and the great explorer suffered severe losses. Provisions ran short, and a hired porter ran away with the medicine chest. From this time Livingstone had no drugs to allay fever, and his health broke down. But he came to the southern extremity of Tanganyika, and the following year discovered Lake Bangweolo. He rowed out to the islands in the lake, and very much astonished the natives, who had never seen a white man before. Extensive swamps lay round the lake, and Livingstone believed that the southernmost sources of the Nile must be looked for in this region. This problem of the watershed of the Nile so fascinated him that he tarried year after year in Africa; but he never succeeded in solving it, and never knew that the river running out of Bangweolo is a tributary of the Lualaba or Upper Congo.