Henry Morton Stanley's first African expedition was in 1871, on assignment for The New York (/places/united-states-and-canada/us-political-geography/new-york) Herald to find Livingstone, who was assumed dead. Stanley's famous question upon finding him, "Dr. Livingstone, I presume?" made Stanley a household name in the explorer frenzy that followed Livingstone's journeys. Although not a scientist, Stanley was sent back out to answer the geographic questions left following Livingstone's death in 1873. Among these, Stanley set out in 1874 to circumnavigate the enormous Lake Victoria to see if it was a single body of water, and—more importantly—to see if it was the much-sought-after source of the Nile River. Stanley also planned to circumnavigate Lake Tanganyika (/places/africa/african-physical-geography/laketanganyika), to see if it was the source of the Nile, as Burton had suggested. Finally, Stanley planned to finish Livingstone's work of mapping the Lualaba River. Livingstone had theorized that the Lualaba, which flowed from Lake Bangweolo, was quite possibly the Nile itself. (Others thought that the Lualaba was the same as the Congo River, not the Nile.)