C28 the "rua" houses. 



of this sort he was a sincere friend, and could not doubt his 

 statement or the wisdom of his caution. 



Thus worried beyond measure by these slaves, and baffled 

 utterly in his work, the doctor, sick at heart and in body, had 

 only one hope left. Dugumbe, who had not yet arrived, was ex- 

 pected daily ; he was bringing his whole family, and proposed 

 fixing his head-quarters in the country and establishing a mart 

 and lines of carriers between his district and Ujiji. The single 

 hope was that this man, who was highest in authority among 

 the traders of the section, might assist him. 



He at length arrived, and Dr. Livingstone offered him $2000 

 for ten men to replace the Banian slaves, and added to this offer 

 the proposition to give him all the goods he had at Ujiji be- 

 sides. Dugumbe said that he would consult his associates and 

 decide what could be done. Besides going down to Lomame the 

 doctor was very anxious to explore Rua, the great district ad- 

 joining Manyuema on the other side of the Lualaba. This 

 great district was distinguished particularly by a wonderful 

 system of underground dwellings, resembling immense caves, 

 which had existed from remote ages. Nothing in all Africa 

 surpasses in magnitude and marvellous structure these wonderful 

 dwellings. Many of them were reported to be so large that en- 

 tire tribes could take refuge in them. The people all spoke of 

 them as having been built by God and not by man. These vast 

 subterranean structures were said to be entered generally by 

 small unpretending openings, but to spread out suddenly into 

 enormous halls and corridors, wonderfully arranged and many 

 miles in extent; some were said to possess different entrances, 

 forty or fifty and sometimes even a greater number of miles apart. 

 The dwellers in these caverns w r ere a warlike race, but, like all 

 the inner tribes of Africa, provided only with their bows and 

 spears, were easy victims of those bloody hordes which came on 

 them armed with guns. They were a bright, intelligent people, 

 and the slaves had sought many pretexts for quarrels with them 

 that they might have excuse for making war, which always 

 means with the Arabs making as many#slaves as possible. 



Dr. Livingstone had seen many of the unfortunate victims of 

 these cruel invasions in the great slave-gangs at different times 

 during his later travels, and among all those whose wrongs had 



