3o6 AIIa)iso}i- JViuji : Sea's Encroachuient on the East Coast. 



cliffs ; here we observe ihe advance of deep water ; and since it is 

 improbable that the general inclinations of the shore and sea 

 bottom have very materially altered since the old days, we may 

 fairly suppose that when those ancient towns existed the five- 

 fathom line was a mile or so out to sea, that is, two miles out 

 from the present coast line (Fig. i). 



'The erosion below low-water level, whilst it deepens the 

 sea bottom, adds to the height of the shore above low-water 

 mark, and this change of position of material, of course, increases 

 the steepness of the shore, and therefore brings deep water closer 

 inland (Fig. 2). 



' I am inclined to believe that, in all situations where the sea's 

 encroachment is steady and continuous, and the material is of a 

 soft and easily eroded nature for a considerable depth below 

 low-water level, no protective works erected on the visible shore 

 between high and low water levels can be expected to permanently 

 arrest the encroachment of the sea, though thev mav afford 

 temporary relief by collecting and retaining material for short 

 periods. 



' Sections taken in a north-easterly direction into the North 

 Sea seem to indicate that the five-fathom line is reached about 

 a mile from the shore, and that the ten-fathom line is found at 



Naturalist^ 



