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
John Davis (English explorer) John Davis (English explorer) John Davis or Davys (c. 155029 December 1605) (b. 1543?) was one of the chief English navigators of Elizabeth I. He led several voyages to discover the Northwest Passage and served as pilot and captain on both Dutch and English voyages to the East Indies. He discovered the Falkland Islands (today a British Overseas Territory) in August 1592. It is important that Captain John Davis of Sandridge should not be confused with a contemporary, Captain John Davis of Limehouse. Both served in the fleet of Captain James Lancaster during the first voyage of the East India