20 
EUROPE AND AFRICA 
the years 1850 to 1855 in the scientific study of the lan- 
guages, peoples, and geography of the region just mentioned 
(west of Lake Chad) including the kingdom of Sokoto. 
Farther south, on the East Coast, Paul du Chaillu traveled 
over the Gaboon River district between 1856 and 1868; 
and, in the interior, David Livingstone explored the Zam- 
besi River, the region about Lakes Nyasa and Tanganyika, 
and crossed the continent to Benguella during the eighteen 
years following 1851. Meanwhile, Burton, Speke, and 
Grant, coming up from the East Coast, had discovered 
Lake Victoria Nyanza and the headwaters of the Nile; and 
Sir Samuel Baker, traversing the whole of that river from 
the north to south, found its other source in Albert Nyanza. 
But it was the work of Dr. Nachtigal, who in 1869 to 
1871 studied carefully the Eastern Sahara and Sudan; of 
Cameron, who crossed the whole continent from the Zan- 
zibar Coast to Benguella between 1873 and 1875; of Sa- 
vorgnan de Brazza, who explored scientifically the whole 
region between Libréville on the Gaboon and the north 
banks of the Congo and Ubangi Rivers from 1874 to 1884; 
and of Henry M. Stanley, who found Livingstone in 1871, 
that drew the attention of the general public to Africa. 
Books were written, money raised, and colonial societies 
formed with the purpose of inducing people to study African 
conditions and to start colonies. By the time Stanley 
returned from his second journey in 1877, with the news 
of the discovery of the great Congo River and its tributaries, 
the statesmen and the intelligent public of Europe were 
taking a very considerable interest in African affairs. The 
general topography of the continent had been mapped, 
— in outline, at least, — the location of all the important 
lakes and waterways pointed out, and the possibilities of 
the different sections as sources of wealth and trade for 
Europe ascertained with a fair degree of accuracy.