SOUTHERN AFRICA. 
97 
fine-grained blue fand, and it generally exceeded a hundred 
yards in width j but the colle£ted ftreamlets, creeping over its 
furface, would fcarcely have furnifhed a quantity of water 
fufficient to turn a mill. The rivers that crofs the Karroo have 
this difference, which diftinguiflies them from rivers in general, 
that, notwithftanding all the tributary ftreamlets that may fall 
into them, the greater the diftance from the fource the lefs 
water they contain. As it feldom rains on the defert, they 
have no fupply but from the fprings ; and the water, in its 
paffage from thefe, is continually lofmg of its bulk both by ab- 
forption and by evaporation. Though the furrounding coun- 
try was deftitute of vegetation, a thick foreft of mimofas 
covered the banks of the Dwyka, and followed it through all 
its windings. This plant grows indeed on every part of the 
defert, on which it is the infeparable companion of all the 
rivers and all the periodical ftreamlets. Should a traveller 
happen to be in want of water, the appearance of the mimofa 
is a fure guide to the place where it occafionally at leaft is to 
be found. 
On the evening of the nineteenth we encamped upon the 
banks of the Ghamka, or Lion's river. The diftance from the 
Dwyka is about twenty miles of the moft beautiful road I ever 
beheld. There was neither ftone nor loofe fand, nor rut, to 
break the equality of the furface, which was level as that of a 
bowling-green, and confifted of a hard bed of clay bound toge- 
ther, and colored brown, with iron. Not a fwell of any fort 
intervened to interrupt the line of the horizon, which was as 
perfect as that viewed over the furface of the fea. Here, too, 
o as 
