Tropical Forests 



kind is a very difficult undertaking. But when once a 

 strip of such jungle has been cut and burnt off, it will, 

 after a few years under crops, be allowed to relapse into 

 bush. Secondary forest will spring up which is by no 

 means so dense or so difficult to clear away as the 

 original jungle. Possibly after some seven years in 

 bush it will again be brought under crops. All this 

 clearance and destruction of the wet-jungle enormously 

 improves the climate, especially from a white man's 

 point of view. 



In Southern Nigeria, according to an interesting report 

 just published, 7 a strip of forest iooo yards wide along 

 both banks of the river has been by law reserved, so that 

 the wet-jungle seems already to require protection by 

 the British Government. 



This same report also contains an excellent account 

 of the way in which in M dry zones " the natural wood- 

 lands tend to be replaced by grass (see above, p. 268). 

 Where the rainfall is less than 50 inches, the natural 

 bush cannot hold its own against fires. Some young 

 trees are destroyed and others injured. Grasses are not 

 killed by these fires, but all valuable dead leaves and 

 other good material is burnt up, and in consequence 

 the land deteriorates steadily. So that there really is 

 some hope that the wet-jungles of Africa and South 

 America will no longer bid defiance to civilised man. 



In Bombay, in those early days when Europeans first 

 established a factory, the mortality was terrible, and quite 

 as bad as it used to be in Old Calabar from 1880 to 

 1890, and this fact is of course quite encouraging for 

 Old Calabar. Mangrove swamps are quite distinct and 

 different from the ordinary wet-jungle. 



The estuaries of tropical rivers are often of enormous 

 extent, for any large stream is apt to split and divide 

 itself into a complex series of winding creeks, a vast 

 confused delta, where the air is for ever hot, moist, 



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