I8o IN THE GUI AN A FOREST. 



inexorable ; like the policeman, it tells the monster 

 obstructionist to move on, and there is no pos- 

 sibility of disobedience. 



However, it sometimes happens that an obstruc- 

 tion of a particularly obstinate nature succeeds in 

 withstanding the flood. Perhaps it has existed 

 long enough to allow the climbers on the over- 

 hanging bushes to lay hold, and the mocca-moccas 

 to grow up and penetrate it like stakes. It was 

 stranded in a shallow, and has been the cause of 

 further deposits on and around it. By and by 

 down comes the flood, bringing with it great 

 masses of similar material, most of which is 

 deposited on the fast -forming bank, until it 

 becomes an impregnable barricade, narrowing the 

 channel to a considerable extent. The waters 

 become higher, and the current swifter. Some- 

 thing has to go, but it is not this late erection. 

 The opposite bank is undermined, one bush after 

 another goes down with the flood, trees fall over 

 and are also carried away, and a few months later 

 the great river has a new bend. This sort of thing 

 is continually going on ; now the stream over- 

 comes the plants, and anon they are borne away to 

 the ocean, the general result being, however, that 

 everywhere except where the bed is rocky the 

 channel is quite unstable. 



