John Hanning Speke Furious and arrived in England on 8 May 1859. Burton was not far behind and he arrived on 21 May 1859. Now further disagreements developed; Burton maintained that they had promised each other in Aden not to make public announcements till they both were back in England and Burton accused Speke of a breach of promise by publicly claiming the source of the Nile was found on their trip. Burton now turned against the theory that Lake Victoria was the source of the Nile (and now said the river flowing "out" of the north side of Lake Tanganyika was the
Hamites races were too broad to have stemmed from a single common ancestor, but were instead consistent with separate racial origins. In his "Crania Aegyptiaca" (1844), Morton analyzed over a hundred intact crania gathered from the Nile Valley, and concluded that the ancient Egyptians were racially akin to Europeans. His conclusions would establish the foundation for the American School of anthropology, and would also influence proponents of polygenism. In the second half of the 19th century, the British explorer John Hanning Speke would further popularize the ancient Hamitic peregrinations in his publications on his search for the source of the Nile