CHAPTER XIII 



RAMBLES TO SEE THE EFFECTS OF WATER ON THE LANDSCAPE 

 THE MAKING OF RELIEF MAPS 



RAMBLES TO SEE THE EFFECTS OF WATER 



Most of the present features of the earth's surface are due to the 

 continued action of water in some form or other. That is to say, 

 the hills and valleys, tablelands and plains, which characterise our 

 English scenery, have all been the result of forces, which act so 

 slowly that a lifetime is often too short to trace the least effect. It 

 must not be thought, however, that for this reason it is useless to 

 try to see for ourselves how this great process of earth-carving is 

 brought about. Far from it. If we keep our eyes open and use our 

 imagination, we shall soon be able to understand how it is that 

 geologists have been able to write the past history of our landscapes. 

 Let us take three common events and see what we can learn from 

 them : a highroad after a heavy shower ; a stream in flood ; and a 

 sea cliff after a storm. A well-engineered road will generally be 

 found to be higher in the centre than at the sides. After heavy rain, 

 tiny rivulets may be seen running from near the centre of the road 

 to the gutters on each side. In fact, the middle of the road acts as 

 a watershed. Look at the little streams, and you will notice that 

 they have cut shallow grooves in the road at the bottom of which 

 gravel can be seen ; while in the gutter there is often to be found an 

 accumulation of sand. The streams, in fact, have washed the lighter 



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