Chap. XXVI. DEAINAGE OF THE GREAT VALLEY. 529 



acquaintance with the river-system, certainly would convey the im- 

 pression. None of the rivers in the valley of the Leeambye have 

 slopes down to their beds. Indeed, many parts are much like 

 the Thames at the Isle of Dogs, only the Leeambye has to rise 

 twenty or thirty feet before it can overflow some of its meadows. 

 The rivers have each a bed of low water ; a simple furrow cut 

 sharply out of the calcareous tufa, which lined the channel of 

 the ancient lake ; and another of inundation. When the beds of 

 inundation are filled, they assume the appearance of chains of 

 lakes. When the Clyde fills the holms (" haughs ") above Both- 

 well Bridge and retires again into its channel, it resembles the river 

 we are speaking of, only here, there are no high lands sloping 

 down towards the bed of inundation, for the greater part of the 

 region is not elevated fifty feet above them. Even the rocky 

 banks of the Leeambye below Gonye, and the ridges bounding 

 the Barotse valley, are not more than two or three hundred feet 

 in altitude over the general dead level. Many of the rivers are 

 very tortuous in their course, the Chobe and Simah particularly 

 so ; and if we may receive the testimony of the natives, they 

 form what anatomists call anastamosis, or a network of rivers. 

 Thus, for instance, they assured me that, if they go up the Simah 

 in a canoe, they can enter the Chobe and descend that river to 

 the Leeambye ; or they may go up the Kama and come down 

 the Simah. And so in the case of the Kafue. It is reputed to 

 be connected in this way with the Leeambye in the north, and to 

 part with the Loangwa ; and the Makololo went from the one, 

 into the other, in canoes. And even though the interlacing may 

 not be quite to the extent believed by the natives, the country is 

 so level and the rivers so tortuous, that I see no improbability 

 in the conclusion, that here is a network of waters of a very 

 peculiar nature. The reason why I am disposed to place a certain 

 amount of confidence in the native reports is tins, — when Mr. 

 Oswell and I discovered the Zambesi in the centre of the con- 

 tinent in 1851, being unable to ascend it at the time ourselves, 

 we employed the natives to draw a map embodying their ideas of 

 that river. We then sent the native map home with the same 

 ■view that I now mention their ideas of the river system — namely, 

 in order to be an aid to others in farther investigations. When I 

 was able to ascend the Leeambye to 14° south, and subsequently 



2 m 



