Chap. XXV. RAINS. 529 



it would scarcely occur to a people, who have few or no cattle 

 or goats, to quarrel about land which they cannot use them- 

 selves. The shallow valleys, along the sides of which the 

 villages were dotted, have, at certain times of the year, rivers 

 running through them, which at this time formed only a 

 succession of pools, with boggy and sedgy spaces between. 

 When the sun is vertical over any part in the tropics on 

 his way south, the first rains begin to fall, and the effect of 

 these, though copious, is usually only to fill the bogs and 

 pools. When, on his way north, he again comes over the 

 same part, we have the great rains of the year, and the pools 

 and bogs, being already filled, overflow, and produce the great 

 floods which mark the Zambesi, and probably in the same 

 manner cause the inundations of the Nile. The luxuriant 

 vegetation which the partial desiccation of many of these 

 rivers annually allows to grow, protects their bottoms and 

 banks from abrasion, and hence the comparative clearness 

 of their water in the greater floods. We were now on the 

 sources of the Loangwa of the Maravi, which enters the 

 Zambesi at Zumbo, and were struck by the great resem- 

 blance which the boggy and sedgy streams here presented 

 to the sources of the Leeba, an affluent of the Zambesi 

 formerly observed in Londa, and of the Kasai, which some 

 believe to be the principal branch of the Congo or Zaire. 



The first or lesser rains take place in this region in 

 November, when the sun is vertical, going south. The greater 

 rains fall in January, February, and March, when he is on his 

 way back to the Equator. Supposing our observation of the 

 cause of inundating floods in south intertropical Africa to 

 be applicable to the north intertropical district, the pools, 

 bogs, and rivers there might be expected to fill, when the 

 sun became vertical, on his way south, and overflow on his 

 return. But this must be decided on the spot. We know from 



2 M 



