David Livingstone many newspapers of the time, and Livingstone experienced great difficulty in raising funds to further explore Africa. Nevertheless, John Kirk, Charles Meller, and Richard Thornton, the scientists appointed to work under Livingstone, did contribute large collections of botanical, ecological, geological, and ethnographic material to scientific Institutions in the United Kingdom. In January 1866, Livingstone returned to Africa, this time to Zanzibar, and from there he set out to seek the source of the Nile. Richard Francis Burton, John Hanning Speke, and Samuel Baker had identified either Lake Albert or Lake Victoria as the source (which was partially correct, as the
John Hanning Speke variety of tropical diseases once they went inland. By 7 November 1857 they had traveled over 600 miles on foot and donkey and they reached Kazeh (Tabora), where they rested and recuperated among Arab slave traders who had a settlement there. In Kazeh Burton became gravely ill and Speke went temporarily blind as they travelled further west. After an arduous journey, the two arrived in Ujiji in February 1858 and became the first Europeans to reach Lake Tanganyika (although Speke was partially blind at this point and could not properly see the lake). They decided to explore the lake but