The River Port Hutton to Smithford 



wild pig, and a wolf, all of which are living in the 

 country at the present time. From this it was evident 

 that we were dealing with a recent deposit. 



Reaching the opposite bank by means of our ship's 

 boat, there being no suitable landing for the steamer, 

 we proceeded to investigate the undrained land, and 

 found it to consist of marshy and swampy ground 

 covered with reeds and rushes and other aquatic and 

 semi-aquatic plants. 



Here there were several breaches in the banks, and 

 in one of them we were able to see a section of the 

 embankment. It consisted of materials similar to those 

 seen in the upper part of the drainage channel section, 

 namely, the finer silts and muds, but strongly bound 

 together by interlacing roots and stems of plants similar 

 to those growing on its upper surface. 



The manner in which these natural embankments 

 are formed is somewhat as follows : The mud-laden 

 waters of the river overflow the banks during wet 

 seasons, inundating the surrounding country, and con- 

 vert it for the time being into an inland sea. Then as 

 the water flows out from the river-course, its velocity is 

 checked by the resistance of the rank vegetation on the 

 margins, and much of its burden of solid particles is 

 deposited. The waters, thus partially clarified, pass 

 outwards over the flood plain, where they deposit the 

 remainder of their load. 



In this way the whole surface of the area is slowly 

 raised, but since the greater amount of the sediment falls 

 close to the side of the river, this part is raised more 

 rapidly than the remainder, and thus the embankments 

 are produced. 



G 97 



