How soil has been made 



121 



Tlie experiment shows us that the fine material 

 washed away by a quickly flowing stream is partly de- 

 posited when the river becomes wider and the current 

 slower, and a good deal more is deposited by the action 

 of the salt water when the river flows into the sea. 

 The rock that crumbles away inland is spread out on 

 the bed of the river or at its mouth. 



The convex side. 



This makes the 



longer course. 



The stream flows* 



quickly, washes 



away the banks, 



and deepens the 



channel 



The concave side. 

 This makes the 

 shorter course. 

 The stream flows 

 slowly, and de- 

 posits silt on the 

 shaded part 



Fig. 65. 

 The two sides of the river at the bend 



The river Stour at Wye showed all these things so 

 clearly that I will describe it ; you must then compare 

 it with a river that you know, and see how far the 

 same features occur. At the bridge the stream was 

 shallow and flowed quickly : the bottom was gritty and 

 pebbly, free from mud, and formed a safe place for 

 paddling. Before the bridge was built there had been 



