Manchester Memoirs, Vol. Ix. (191 6), No. tf. 9 



rift valley, containing lake Tanganyka, we are told that, 

 " Here Cameron found the surface not regularly terraced, 

 but retaining walls of loose stones dispersed at intervals, 

 which serve to hold the soil in place, without greatly 

 altering the natural slope. The scene recalled the 

 terraced heights of Switzerland, and the people working 

 there looked like flies on a wall." 2S 



Still further to the south terraced irrigation has been 

 carried on to a remarkable degree in Rhodesia. Hall, in 

 an account of the Inyanga ruins, situated 250 miles north 

 of Great Zimbabwe says, " On the summits of the hills 

 are stone forts, possibly a hundred of these structures, 

 while up the sides of the hills, from base to summit, are 

 stone terraces. Round their lower flanks run stone 

 aqueducts, each, one, two or three miles in length." He 

 further remarks that "the great extent of country covered 

 with these remains is simply marvellous." He goes on 

 to say in another place, " one of the most extraordinary 

 features of the Inyanga Range is the vast number of old 

 aqueducts, some two miles or more in length, running 

 from artificial dams on the mountain streams, and 

 crossing from hill to hill in a most remarkable manner. 

 " Whoever constructed these aqueducts must have been a 

 people thoroughly conversant with engineering, for their 

 levels are beautifully and exactly carried out in spite of 

 all natural obstacles, and not an inch of fall is wasted 

 throughout the length of their courses. These are a 

 marvel to all modern engineers who inspect them. 

 Evidently they were used for purposes of irrigation. . . " 

 And again he says : — " Perhaps the feature which most 

 strikes the visitor to this district is the hill terraces. 

 These are found in hundreds. 



"These terraces cover the hills from base to summit, 



- 3 Ibid, pp. 570-1. 



