Sir Richard Francis Burton 
Two Trips to Gorilla Land and the Cataracts of the Congo Vol I & Vol II 

(Excerpt): "The notes which form the ground-work of these volumes have long been kept in the obscurity of manuscript: my studies of South America, of Syria and Palestine, of Iceland, and of Istria, left me scant time for the labour of preparation. Leisure and opportunity have now offered themselves, and I avail myself of them in the hope that the publication will be found useful to more than one class of readers. The many who take an interest in the life of barbarous peoples may not be displeased to hear more about the Fan; and the few who would try a fall with Mister Gorilla can learn from me how to equip themselves, whence to set out and whither to go for the best chance. Travelling with M. Paul B. du Chaillu’s "First Expedition" in my hand, I jealously looked into every statement, and his numerous friends will be pleased to see how many of his assertions are confirmed by my experience."