John Hanning Speke questions about the height and extent of the lake could not be answered easily. Speke's eyes were still bothering him and he only saw a small part of the southern end of the lake and his view was blocked by islands in the lake so he could not judge the size of the lake well. However, Speke did estimate the elevation of Lake Victoria at 4000 feet by observing the temperature at which water boiled at that level. (This lake's being substantially higher than Lake Tanganyika did make it a more likely candidate for the source of the Nile.) From
Mountains of the Moon (film) Mountains of the Moon (film) Mountains of the Moon is a 1990 Rankcolor theatrical film depicting the 1857–58 journey of Richard Francis Burton and John Hanning Speke in their expedition to Central Africa – the project that culminated in Speke's discovery of the source of the Nile River. The expedition led to a bitter rivalry between the two men. The film stars Patrick Bergin as Burton and Iain Glen as Speke. Delroy Lindo made an early film appearance as an African native the adventurers meet. The film was directed by Bob Rafelson, for whom this was something of a dream