two thousand feet in coming
to it from Kolobeng. It is the southern and lowest part of the great
river system beyond, in which large tracts of country are inundated
annually by tropical rains, hereafter to be described. A little of that
water, which in the countries farther north produces inundation, comes
as far south as 20d 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 Tzo 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 happened in modern times--then
this little arm would prove a convenient escapement to prevent
inundation. If the lake ever becomes 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 th