Joseph Thompson 
To The Central African Lakes and Back [PDF ebook] 
The Narrative of The Royal Geographical Society’s East Central Expedition 1878-80, Volume 1

First published in 1968: This, the record of the author’s first journey into the interior of Africa, established his credentials as an explorer of the first rank. Although he made no startling discoveries and his experiences lack the dramatic impact of those retailed in Through Masai Land, his more widely known and subsequent narrative, To The Central African Lakes added measurably to Europe’s knowledge of a part of eastern Africa which hitherto had only been understood in imperfect outline.