THE NGAMI. 79 



tion, comes as far south as 20° 20', the latitude of the upper end 

 of the lake, and instead of flooding the country, falls into the 

 lake as into a reservoir. It begins to flow down the Embarrah, 

 which divides into the rivers Tzo and Teoughe. The Tzd divides 

 into the Tamunak'le and Mababe ; the Tamunak'le discharges 

 itself into the Zouga, and the Teoughe into the lake. The flow 

 begins either in March or April, and the descending waters find 

 the channels of all these rivers dried out, except in certain pools 

 in their beds, which have long dry spaces between them. The 

 lake itself is very low. The Zouga is but a prolongation of the 

 Tamunak'le, and an arm of the lake reaches up to the point 

 where the one ends and the other begins. The last is narrow 

 and shallow, while the Zouga is broad and deep. The narrow 

 arm of the lake, which on the map looks like a continuation of 

 the Zouga, has never been observed to flow either way. It is as 

 stagnant as the lake itself. 



The Teoughe and Tamunak'le, being essentially the same river, 

 and receiving their supplies from the same source (the Embarrah 

 or Varra), can never outrun each other. If either could, or if 

 the Teoughe could fill the lake — a thing which has never hap- 

 pened in modern times — then this little arm would prove a con- 

 venient escapement to prevent inundation. If the lake ever be- 

 comes lower than the bed of the Zouga, a little of the water of 

 the Tamunak'le might flow into it instead of down the Zouga ; 

 we should then have the phenomenon of a river flowing two ways ; 

 but this has never been observed to take place here, and it is 

 doubtful if it ever can occur in this locality. The Zouga is broad 

 and deep when it leaves the Tamunak'le, but becomes gradually 

 narrower as you descend about two hundred miles ; there it flows 

 into Kumadau, a small lake about three or four miles broad and 

 twelve long. The water, which higher up begins to flow in April, 

 does not make much progress in filling this lake till the end of 

 June. In September the rivers cease to flow. When the supply 

 has been more than usually abundant, a little water flows beyond 

 Kumadau, in the bed first seen by us on the 4th of July ; if the 

 quantity were larger, it might go further in the dry rocky bed of 

 the Zouga, since seen still further to the east. The water supply 

 of this part of the river system, as will be more fully explained 

 further on, takes place in channels prepared for a much more 



