SURVEY OF LAKE TANGANYIKA. 603 



the waters flowed into, instead of out of, the lake. Lieutenant Cameron pro- 

 ceeded for about four or five miles along the stream, the current of which 

 runs from one to two knots per hour, but further navigation was impeded by 

 floating grass and large rushes. In a letter to Lord Derby, from Kawele, 

 Ujiji, May 14, 1874, Lieutenant Cameron says : — " I think, from what I have 

 heard from the Arabs here, that the Lualaba is the Congo. One important 

 fact mentioned by my Arab informant requires looking into. He said he 

 met no English merchants, although he heard of them and of our men-of-war, 

 as all the white merchants he met traded in slaves. This, if true, would point 

 to the Spanish and Portuguese merchants on the Congo. Of the vast import- 

 ance to the trading community of England of the Congo and Lualaba proving 

 one there is little for me to say, but I will glance over the principal articles 

 of export. The Guinea palm extends, I believe, from the West Coast to here; 

 india-rubber is abundant in Manyema ; sem sem (from which much so-called 

 olive-oil is extracted) grows well wherever cultivated; the castor-oil plant 

 grows almost wild ; ground nuts the same ; copper and gold are found in Ka- 

 tanga ; cotton grows well, and of to or three kinds ; coffee is reported to grow 

 wild ; ivory, it is well known, mostly comes from this portion of Africa ; there 

 are many sorts of fibrous substances which might be exported with advantage, 

 and the various millets and maize grow in such abundance that they would 

 form a profitable export; rice also grows most luxuriantly wherever culti- 

 vated. The only obstacles to a free water communication of which I know 

 are the Yellala Falls and the rapids on the Lualaba, a short way above the 

 Nyangwe. The Lukuga is at present obstructed with grass, but a way might 

 easily be cut through that. The trade at present is about here entirely in 

 the hands of Arabs who, when in Manyema, live nearly entirely by plunder, 

 and who take the wretched inhabitants as slaves to carry their ivory and 

 other goods. The efforts of England will, I trust, be successful in putting 

 down the slave-trade by sea ; but at present they leave untouched an equally 

 crying evil, the internal trade, which is rapidly depopulating vast districts. 

 In going round the lake I was constantly shown places where villages had 

 been, and when I asked where the former inhabitants were, invariably 

 received the same, ' Killed, or carried off for slaves.' The price of a slave 

 is only 5 dotis (20 yards) of calico, while the hire of a passage is 5^ from 

 Unyanyembe here, so that it is far cheaper to buy slaves than to hire porters, 

 besides which no porters are obtainable in Manyema, and the whole trade 

 there is carried on by means of slaves. The Arabs take with them a horde of 

 Wagwana or free men, armed with muskets, and carry a few stores by means 

 of domestic slaves, and the ivory, of which they obtain large quantities, is all 

 brought by fresh-caught slaves to Ujiji. The numbers of Arabs settling in 

 the country is constantly increasing, and they all have large numbers of 

 slaves for domestic purposes, for cultivating their gardens, and for porters. 



