334 GRASS OF THE PLAINS. 



vegetation has prevented the country from becoming furrowed by 

 many rivulets or "nullahs." Were it not so remarkably flat, the 

 drainage must have been effected by torrents, even in spite of the 

 matted vegetation. 



That these extensive plains are covered with grasses only, and 

 the little islands with but scraggy trees, may be accounted for 

 by the fact, observable every where in this country, that, where 

 water stands for any length of time, trees can not live. The 

 want of speedy drainage destroys them, and injures the growth 

 of those that are planted on the islands, for they have no depth 

 of earth not subjected to the souring influence of the stagnant 

 water. The plains of Lobale, to the west of these, are said to 

 be much more extensive than any we saw, and their vegetation 

 possesses similar peculiarities. When the stagnant rain-water 

 has all soaked in, as must happen during the months in which 

 there is no rain, travelers are even put to straits for want of 

 water. This is stated on native testimony ; but I can very well 

 believe that level plains, in which neither wells nor gullies are 

 met with, may, after the dry season, present the opposite extreme 

 to what we witnessed. Water, however, could always be got by 

 digging, a proof of which we had on our return when brought 

 to a stand on this very plain by severe fever: about twelve 

 miles from the Kasai my men dug down a few feet, and found an 

 abundant supply ; and we saw on one of the islands the garden 

 of a man who, in the dry season, had drunk water from a well 

 in like manner. Plains like these can not be inhabited while 

 the present system of cultivation lasts. The population is not 

 yet so very large as to need them. They find garden-ground 

 enough on the gentle slopes at the sides of the rivulets, and 

 possess no cattle to eat off the millions of acres of fine hay we 

 were now wading through. Any one who has visited the Cape 

 Colony will understand me when I say that these immense crops 

 resemble sown grasses more than the tufty vegetation of the 

 south. 



I would here request the particular attention of the reader to 

 the phenomena these periodically deluged plains present, be- 

 cause they have a most important bearing on the physical geog- 

 raphy of a very large portion of this country. The plains of 

 Lobale, to the west of this, give rise to a great many streams, 



