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
Nile (TV series) of discovering where the Nile was born, but for centuries the river kept its secrets close. The obsession grew and by the mid-19th century some were prepared to risk their lives to be the first to discover the source of the Nile. Nomads first settled along the banks of the Nile around 5000 BC and replenished by annual floodwaters grew into the Ancient Egyptian civilisation but the source of the miraculous waters remained a mystery to them. The Royal Geographical Society dispatched Richard Burton and John Speke to Lake Tanganyika to find the source in 1857 but unable to complete