a27 
become deeper and deeper, they widen out, and dongas are formed 
which carry off the rainwater rapidly, lower the water-level, etc. 
Attention has been frequently called to this evil, and it is hoped 
that before long active steps will be taken to prevent the Karroo 
from becoming a real desert. Some farmers have at all events 
tried to preserve the more or less extensive alluvial soils (which 
are probably the most productive in the world) from being washed 
way. They have built walls and formed terraces to break the 
force of the water-currents, and have blocked up dongas which 
soon get filled with silt that in many cases is excellent for 
crops. The terraces act at the same time as reservoirs, and on 
east, and is also widely pe towards the west. It is not touched 
by any kind of stock. 
Flora, are seen as far as the eye can reach: roteaceae, Resti- 
aceae, Bruniaceae, species of Cliffortia, Watsonia, Ericaceae, 
sandstone, partly on Bokkeveld beds, which, having been eroded 
into steep slopes, retain less moisture, and consequently the forest 
on them is not so tall as that‘on the Table Mountain sandstone. 
A2 
