On the 15th of July, 1869, after camping at Kassengé, when on his way to Manyema, he writes in his journal the following opinion of Lake Tanganika; “Tanganika narrows at Uvira or Vira, and goes out of sight among the mountains; then it appears as a waterfall into the Lake of Quando, seen by Banyamwezi.” In his letters home Dr. Livingstone constantly made mention of two lakes, called Upper Tanganika, which Burton discovered, and Lower Tanganika, which Sir Samuel Baker discovered, and which formed, as he said, the second line of drainage trending to and discharging its waters into the Nile. He makes record in his Journals of the causes which induced him to verify his opinions by a personal investigation of the north end of Lake Tanganika on the 16th of November, 1871, a few days after my arrival, at Ujiji, I being the fourth European who had arrived on the shores of the Lake, in this manner:— “_16th November, 1871._—As Tanganika Explorations are said by Mr. Stanley to be an object of interest to Sir Roderick, we go at his expense and by his men to the north end of the lake.” “_24th November._—To Point Kisuka in Mukamba’s country. A Mgwana came to us from King Mukamba, and asserted most positively that all the water of Tanganika flowed into the River Lusizé, and then on to Ukerewe of Mteza; nothing could be more clear than his statements.” “_25th November._—Our friend of yesterday now declared as positively as before, that the water of Lusizé flowed into Tanganika, and not the way he said yesterday! Tanganika closes in except at one point N. and by W. of us.” “_26th November._—The end of Tanganika seen clearly, is rounded off about 4′ broad from east to west.” On the 29th of November, Livingstone and I, in a canoe manned by several strong rowers, entered into Lusizé, or Rusizi, and discovered that it flowed _into_ Lake Tanganika by three mouths with an impetuous current. The explorations of Livingstone and myself in November 1871 to the north end of Lake Tanganika resolved that portion of the problem, but described only about thirteen miles of coast unvisited by Burton and Speke. On our way back, however, by a southern route to Unyanyembé, we added to the knowledge of the Tanganika coast-line, on the eastern side from Kabogo Point as far as Urimba, about twenty miles farther than Speke had seen. In August 1872, about five months after I had departed from him homewards, he recommenced his last journey. On the 8th of October of the same year he saw the Tanganika again about sixty miles south of the point where he and I bade farewell to the lake, eight months previously. Clinging to the lake, he travelled along the eastern shore, until he reached the southernmost end of it.