EATE OF EEOSION OF THE SEA-COASTS OF ENGLAND AND WALES. 905 



I knew it to be twenty years ago. This was shown by some of the foundation screws 

 of the piles of the pier having been washed bare. 



The ordinary cost of keeping the present sea-wall in repair amounts to over 1,500?. 

 per annum, in addition to which much loss and anxiety are frequently caused during 

 a heavy storm. 



Attempts have been made to replace the shingle driven away by the wall, by 

 erecting timber groynes. The result is that shingle may sometimes be found on their 

 north and sometimes on their south sides, but never during heavy weather can any 

 reliance be placed on an accumulation to assist the sea-wall. The general level of the 

 beach is not in the least raised ; the seaward ends of the groynes have deep pools of 

 water around them, and the waves driven along them to their shore ends have struck 

 heavily against the wall and have greatly worn the stonework. It is only by very 

 constant attention that the wall is maintained. 



Whilst this damage continues to be done at Blackpool thousands of tons of 

 shingle are driven past it, as before described. 



yt. Anne's, a new watering-place near the most northern boundary of the estuary 

 of the Kibble, is built on what was a few jears ago a rabbit-warren, underlying it 

 being the old shingle ridges before mentioned. 



When the town was lirst laid out a sea-wall, smaller, but of similar outline to the 

 one at Blackpool, was built, much shingle being left between it and the sea. Soon 

 after its erection the shingle began to be driven away, and it became necessary to 

 lower the foundations several feet, as was found to be the case at Blackpool. 



Many attempts have been made to protect tbe wall by groynes constructed of 

 timber, but the invariable result Ijas been to produce an increased scour. I have 

 myself made several attempts, but it was not until I discarded solid groynes and sub- 

 stituted open ones that I met witli any really good result. 



After various modifications I put up several open groynes at right angles with the 

 wall, their sides or panels being made of wrought-iron g^ratings, so as to retain the 

 shingle while allowing the water to pass through tliem freely. These produced a 

 very considerable accumulation of shingle, which after several years still remains 

 there. 



Subsequently, during a heavy gale, a considerable length of another portion of the 

 wall was undermined, and, as it was in imminent danger of being washed down, I 

 fixed several open groynes in front of it. The result was that after the next rough 

 tide a large quantity of shingle was trapped. Then, as the groynes became buried, 

 they were lifted up from time to time, so that this part of the beach was raised from 

 10 to 12 feet above the level which existed when I commenced operations, and the 

 wall has since remained safe. 



After this experience the owners of the property were so convinced of the benefit 

 derived from having the open groynes erected that they purchased from me the right 

 to place them along anj' part of their frontage (about one mile). Having afterwards 

 learnt that they were about to erect a number of short groynes, I pointed out that 

 they would not be likely to attain their object. Short groynes could only lead to the 

 formation of a narrow and steep incline of shingle, whereas they should strive to 

 accumulate a broad, tlat incline upon which the waves would break before reaching 

 the sea-wall. They did not, however, carry out this suggestion, so that I fear little 

 good can be expected from these additions. 



The foregoing evidence appears to me to show — 



(a) That a sea-wall causes the shingle in front of it to be driven away. 



(b) That solid groynes, especially if high ones, are most mischievous, as 

 owing to the scour they produce during heavy weather they drive the shingle 

 seawards. 



On the other hand, with open groynes it is impossible for the shingle to be 

 driven away, and in practice they have retained it for several years, where it 

 still remains. 



E. Notes on the Coast of Durham, between the rivers 



Tyne and Wear, 



By Hugh Bkamwell, The Whitburn Coal Company, Limited, South Shields. 



2. The nature of the coast is as follows : — a. 1^ mile of sand immediately 

 south of the Tyne ; 4 miles of limestone cliffs (magnesian limestone 

 Permian); 1 mile of sand, the Whitburn sands ; | mile of limestone cliffs 



