EIVEES. 7 



sluo-o-isli rivers as the Juba, Tana, Lufiji, and Rovuma. But soutli of the great 

 central lacustrine plateaux the Zambezi, whose furthest headstreams rise near the 

 west coast, drains a vast tract of country estimated at about 750,000 square miles, 

 or nearly three times the size of France. In volume it ranks third amongst African 

 rivers, but in length fourth only. Still farther south the Limpopo has also a con- 

 siderable discharge ; whereas the Orange, whose basin exceeds 400,000 square miles 

 in extent, contributes to the South Atlantic very little of the rainfall collected in 



Fig. 3. — Outflow of Lake Nyanza, according to Speke. 

 Scale 1 : 1,000,000. 



n 



180 Miles. 



the gorges of its upper course. The Kunene and Koanza, which follow from south 

 to north, although more copious, have still but a slight volume compared with their 

 respective areas of drainage. The same may be said of the Ogowe, which rises in 

 the peninsular tract formed by the great bend of the Congo east of equatorial 

 Guinea. 



The Niger, or " Nile of the Blacks," forms with the Nile, Congo, and Zambezi, 

 one of the four great arteries of Africa. Even down to the beginning of this cen- 

 tury many geographers still supposed that the Nile and the Niger mingled their 



