ON THE EROSION OF THE SEA-COASTS OF ENGLAND AND WALES. 373 



9. a. I have not had an opportunity of measuring tliis. d. From 3 to 4 inches. 



10. I should say stationary. 



13. The degradation of the cliffs is due to the water issuing from the base of the 



gravel over the slippery clay surface. 



14. The face of the cliS has slipped away at a rate of 3 feet per annum, taking an 



average line of about f mile in length during the last twenty-two years. This 

 is the rate as ascertained during that period, and it is probable that this has 

 been the average rate for a longer period. 



The shingle beach appeared to me to be stationary ; so now tliat drains 

 have been laid up the slipped slopes of the cliff to remove the water issuing 

 between the gravel and clay, the slopes will become consolidated, and slipping 

 will no longer take place. 



15. It must he explained that the course of the channel of the river Avon formerly 



ran parallel to the beach eastwards for some distance from its mouth in 

 Christchurch Harbour, but certain works executed some lime ago by some 

 landowner at the mouth had the effect of diverting the course straight out to 

 sea, and thus the channel parallel to the beach has become stopped. No 

 doubt this is the cause of the present stationary character of the beach, for 

 otherwise erosion would take place, and the slipping of the cliff further 

 facilitated bj' the undermining of the toe. 



16. No. 



17. No. ^ 



Sussex Coast. 



By KiCHAED F. Grantham, M.Inst .C.E. 



(I) Opposite Lancing. 



1. Sussex coast, opposite Lancing. It is that portion which lies between ' Shop's 



Dam ' and the gap in the Worthing and Lancing Eoad, referred to in my 

 father's returns, Nos. II and 12 in the Committee's Report, dated I88o. 



2. The main features of that part of the coast are described in those returns, but I 



have, within the last two years, constructed nine groynes between Shop's Dam 

 and the gap in the road, a distance of about 1,100 yards. 



3. That is westwards of the groynes erected under my father's superintendence ; but 



I have had an opportunity of making a survey of that part of the coast, which 

 shows exactly the rate at which the sea has been advancing opposite Lancing. 



8. Partly of shingle, partly of sand foreshore. Opposite the Coastguard Station, 



west end of Lancing, chalk rocks and flints, covered with seaweed, can be seen 

 at low water slightly above the level of the sand foreshore. In storms the 

 flints are loosened, raised up, and washed up on the shore. 



9. The shingle lies in the form of a high bank, thus : 



Fig. 2. 



w^^^^^--"" ■'"■'■ "■■■• ""■■ ' ■'" 



The base of the shingle bank is about 500 feet broad, and the top of it is 

 about 6 feet above H.W.O.S.T. ; the land behind is below the level of H.W. 

 Formerly, in storms, the sea washed the shingle back, encroaching further 

 and further on the low-lying land. There is a ' fall ' of shingle, but this varies 

 according to the state of the sea. It is generally just above H.W. springs. 



11. I think that until the groynes were erected the quantity of shingle remained 



constant, but it was perpetually being driven back. 



12. a, b, and c. The new groynes point south-east at a rather greater inclination 



■with the shore line than those erected by my father. Their length is 300 feet, 

 and the width apart is 400 feet, except the three groynes at the west end, which 

 are 350 feet in length and rather closer together, d. The top end is 18 feet 

 above CD. and 8 feet above H.W.O.S.T. e. Timber partly memel, partly 



