KATE OF EROSION OF THE SEA-COASTS OF ENGLAND AND WALES. 915 



their length through the sand and shingle into the clay battering on the outside, 

 their heads inclining inwards towards each other and nearly meeting, the intervening 

 space being filled with rough Kentish ragstone; the piles in the longitudinal 

 direction of the groyne are driven close together. Similar piling is used for pro- 

 tecting the margins of the stone slopes. 



Where longer and loftier groynes than usual have been erected for the protection 

 of projecting points, such as the west end of Neptune Terrace, or for a particular 

 purpose, like the hotel-groyne, outer steps have been formed by rows of smaller piles, 

 driven sloping and parallel with the inner piles, and filled in with stone, forming an 

 outer ledge, sometimes constructed to windward, sometimes to leeward, and in the 

 case of the hotel-groyne on both sides. The large groyne at the east end of your 

 property has six parallel rows to leeward ; the single and ordinary construction of 

 groyne is generally from 2 to 3 feet above the shore, which is usually 12 inches 

 higher on the east side than on the west. The short groynes have a fall of from 

 7 to 1 to 10 to 1, i.e., taking the slope of the beach, the larger groynes are at their 

 outer ends correspondingly more easy in inclination, being as much as 30 to 1, and 

 even more corresponding with that of the foreshore. 



There are some cases where, from this recession of the shingle, or from the pecu- 

 liarity of position, like the groyne at the end of Neptune Terrace, the groynes are much 

 higher above the shore. The above, however, is the medium where the wall, shingle- 

 slope, and groynes are in good order; in other cases, as at the east end of these 

 defences, where the shingle has accumulated, the groynes are not much above its 

 surface. The prevailing mode appears to have been to run them out at right angles, 

 or nearly so, to the length of wall they appertain to, and consequently presenting 

 varying angles to the prevailing wind, with spaces or bays between of from one-half 

 to one-fourth their respective length of groyne. In some cases the ends of the groynes 

 have been connected together, with the object of retaining the shingle on the recoil ; 

 and in otlier cases triangles have been formed within the bays by two inner and 

 shorter groynes running out at an acute angle from the roots of the main groynes, and 

 meeting and forming an apex seaward, apparently with the same purpose — viz., to 

 retain the shingle on the return wave. This may be seen at Cheney Point, where, 

 however, these artificial works are so close together — in one case two groynes cross 

 each other at an angle that it becomes almost an artificial slope. 



In the two plans proposed for the repairs and extension of your groynes the 

 principles of construction hitherto followed have been adopted, and differ only as to 

 the number, extent, position, and direction of the groynes. The aggregate length of 

 work in each case, and consequent cost, are nearly the same. 



The plan proposed by Major Nugent last October recommended the elongation, 

 in certain instances, of existing sound groynes, and the introduction of new inter- 

 mediate grojmes, this view, no doubt, being encouraged by the favourable state of 

 the beach at the eastern end beyond Cheney Point. 



In this plan the groynes are nearly parallel to each other, from the east end to 

 the hotel-groyne, and at right angles nearly to the mean line of high water. Those 

 opposite the recess, between Neptune Terrace and the return end of the stone wall 

 near the windmill, are about 53 feet apart on an average, giving bays of about one 

 third the mean projection of the groynes ; thence to the hotel-groyne the bays average 

 from 32 to 33 feet in width, or from one fourth to one fifth the projections. Under the 

 lee of the hotel groyne four groynes were proposed to be placed in a radiating position 

 from a common centre, about 90 feet north-east of the outer end of the hotel-groyne, 

 the bays between these groynes having a mean width of 45 feet, or about half the 

 mean length of these radiating gprojnes, the western one of which would be detached 

 from the shore at a very acute angle in a north-easterly direction. From this point 

 westward to just past the path to Blue Town the groynes are proposed to be placed 

 parallel to the old ones, i.e., at right angles nearly to high-water mark, and to the 

 mean direction of the shingle 'full,' dividing the shore in that extent into No. 15 

 bays, with a mean width of 37 feet each, equal to one third of length of groynes. 



In the plan for the current year, by Colonel Montagu, the length between the 

 road to Blue Town and the east return of the stone wall at the mill is alone considered. 

 The groynes proposed are longer, and the bays wider, than in last year's plan. In 

 order to retain the shingle after it has passed to the westward, the direction given to 

 the new groynes is in two cases more westerly, with an obtuse angle to windward and 

 an acute one to leeward. In a third case, the second from the west end, this direction 

 is reversed ; and to aid in promoting deposit, another principle, which has before been 

 adopted on this shore (though not to the same extent), is here called in aid, viz., to 



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