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erected for the purpose of collecting or preventing the denudation of the sand from the beach consist of a layer of mattress-work made of willows secured in place by piles. This is used for the purpose of preventing the stones sinking into the fine sand. On this mattress-work is placed a layer of rubble basalt about 18 inches in thickness. These groynes extend to some distance below low water, certain lengths reaching at Scheveningen to 325 yards, the average length being about 120 yards, and the full width 40 feet, the distance apart being a little more than that of the length. The willow mattress does not last longer than about twenty years, and consequently the groynes frequently require reconstruction. Similar groynes are used on other parts of the coast. On some of the groynes the piles project above the shore as much as 6 feet. There is a strong controversy as to whether this does good or harm, the more general modern opinion being that they are injurious. In addition to their uselessness, these piles, projecting above the beach over a wide area, are a great eyesore and give a dismal appearance, and tend greatly to destroy the beauty of the shore where they are used in front of a watering-place. In some cases these groynes collect sand or raise the beach, but their general effect is only to prevent denudation. Where the beach is steep, say at an angle of 1 in 25, they are most effective, but when the slopes reach 1 in 50, little or no accretion takes place.

At West Kapelle, the groynes for the protection of the coast of the Island of Walcheren, and more particularly of the sea-bank between Domburg and West Kapelle, are of a very substantial character. They vary in length, the average being about 130 yards, the maximum distance apart being 300 yards. They consist of from two to four rows of fir piles, 8 inches in diameter, 12 to 18 feet in length, and projecting 6 feet above the beach, driven from 6 to 8 inches apart. They are connected by walings on each side, and divided into bays by cross-timbers. The space between the piles is filled with clay, brushwork, and stones, some of these being 2 feet square. They rake at a broken slope, the angle varying from 1 in 23 near the bank to 1 in 35 further out. At the end of each groyne mattresses are placed 130 feet in length. The piles formerly were studded with worm nails to 64 feet below high-water level, having broad flat heads, the rust from which stopped the action of the teredo.

At Schleswig and Holstein the sea-dykes are protected by

They rake it to 1 in 35 40 feet in lengths

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groynes, which run out a long way across the sands. Experience has shown that when these groynes extend only a short distance, although they are serviceable in preventing the beach from being hollowed out, they do not lead to any accumulation of sand. When they are extended outwards from 430 to 560 yards they afford practical protection to the sea-wall, and cause a rise in the upper part of the beach. These groynes are from 2 to 3 feet high, made of mounds of earth covered with grass and matting, having a top width of 4 feet, with slopes of 4 to 1 on the windward side and 3 to 1 on the lee side (Min. Proc. Inst. C.E., vol. xxi.).

On the north coast of the Island of Schouwen, for the purpose of preventing the waves from the North Sea forming deep lows close to the shore and endangering its safety, groynes were placed at right angles to the coast, spaced 164 yards apart. These were constructed of layers of fascines covered with stones and fastened down to the beach with oak staves. The result was satisfactory. The cost of maintenance of from 18 to 25 groynes between the years 1872–86 was given as £5703, equal to £19 a year for each groyne.

For the purpose of protecting the coast of Mecklenburg near Rostock, and to keep open the entrance of the Warnemunde by trapping the sand drifting along the coast, and thus creating a beach, groynes spaced 1} times their length were erected in 1889, for a length of 27 miles along the coast, and carried to a depth of 8 feet. They consisted of piles 8 inches in diameter driven 31 feet, and pitched in two rows 24 feet apart. Fascines were packed between the piles, and secured by transverse timbers and walings. The piles at the end of the groynes were sunk 5 to 6 feet, and the fascines weighted with stones. The result was quite successful, the drift of the sand, which is very fine, being stopped by the fascines, and a beach formed 55 yards wide and to a depth of 64 feet.

INDEX

60

Barricane Bay shell sand, 326

Barry Island, 323
ABBOTSBURY, Chesil Bank, 144, 147 Barry, Sir J. Wolfe, Dymchurch sea-wall,
Abergele, 315

203
Aberthaw, 323

Bars, Boston Deeps, 242, 70
Aberystwyth, 319

- river Adur, 182
Admiralty Pier, Dover, 209

- , river Blyth, 71
Adur, river, diverted by shingle, 69, 182 - river Deben, 71
Aldborough, or Aldeburgh, 282, 27

—, river Mersey, 70, 314
Alde, river, 283

Basalt, use for sea-walls, 197
Alderney breakwater, 15, 20

Bawdsey, 284
Aldrington, 184

Bay du Vay shingle-bank, 333
Aldwick, 177

Beach protection, object to be attained, 3
Alluvium, 23, 57, 60

Beaches, control of Board of Trade over.
- , analysis and composition of, 58, 57 L See BOARD OF TRADE
- at mouth of Humber, 239

- lows or swills in, 40, 118, 235
- , clay, 57

- meaning of word, vii.
, effect in making water turbid, 59

-, raised, 146, 149
, formation into salt marshes, 60

-, removal of material from, law relating
found in ocean at mouth of rivers, 50, to, 5; when this may be permitted, 6

-, supply of material on, limited, 4, 33
- not derived from sea, 59

Beachy Head, 191
not drifted along the coast, 58, 61 Beacon Cliff, 290
settlement in salt and fresh water, 62 Beal Point, 213
silt, 57

Beard, Mr., system of groynes, 127, 194
, size of particles, 57

Bee sands, 112
, specific gravity, 57

Beer Head, 139
-, tíme taken to settle in water, 65 Belgium, coast of, 340
Alnwick Bay, 214

Bembridge, 173
Alum Bay, 168

Benacre Broad, 275
America, sand-spits on East Coast of, 45, 46 Bents. See SAND-DUNES
Anglesey coast, 317

Berrow Flats, 324
Annaside, 303

Berry Head, 133
Antifer, Cape, 333

Berwick, 214
Arrish Bay, 157

Beveland, 342
Arromanches, 334

Bexhill, 193
Atherfield, 170

Birchington, 296
Atherington, 181

Blackgang Chine, 170
Ault, 337

Blackpool coast, 307, 84, 105
Axe river diverted by shingle, 69, 139

Bay, 132
Axmouth, 139

Blakeney, 246
Blanc Nez, Cape, 339
Blankenbergh, 341
Blue Anchor coast, 324

Blyth coast, 214
BABBACOMBE BAY, 135

Blyth, river, 279
Baker, Sir B., on pressure of earthwork, 91 | Board of Trade, inspector sent to hold
Ballard Point, 158

inquiry as to damage to coast from
Baltic, sand-spits in, 44

storms, 249, 264
Banbury Castle, 213

- care of Spurn Point, 237
Barfleur, Cape, 333

-

permission required from, to
Barmouth, 318

erect groynes on a beach, 128, 159, 249,
Barnstaple Bay, 326

274

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Board of Trade, powers as to removal of | Case and Gray, Messrs., Report on Holder-
material from beaches, and prevention of ness coast, 224
same, 5, 176, 238, 315

Cayeux, 337
Bognor, 176, 101

Cayton Bay, 218
Bonchurch, 171

Chale Bay, 170
Bootle, 303

Chalk cliffs, coast of France, 333-337
Borth coast, 318

- flints. See FLINTS
Bouldnor, 174

Charmouth, 141
Boulogne, 338

Cherbourg pier, 80, 15, 18, 19
Bournemouth Bay, 161, 35

Chesil Bank, 144, 25, 17
Brading Harbour, 173

Chesilton, 145
Brancaster, 247

Chewton landslip, 164
Branscombe, 138

Chichester Harbour, 167
Braunton Burrows, 326

Chines, 170
Braystones, 302

Chit Rocks, 138
Bridlington, 227, 220, 122, 83

Christchurch, 162, 16
Bridport, 142, 143

Clacton, 291, 90, 102
Brighton, 183

Clay, 57
Bristol Channel, 322

- rate of deposit in water, 65
British Association, papers read at, vii., Cleethorpes, 238
277

Cley, 247
- Reports, 140, 162, 167, 180, 181, 200, Cliffs, destruction of, 31

212, 222, 281, 294, 300, 306, 308, 313 Coast, destruction, v., 2, 23, 31
Broad Sands, 133

- cost and policy of preservation, 2
Broads in Norfolk, 262, 265

- , example of cost of protection on
Brook Point and Bay, 170

Yorkshire, 2; scheme for protection, 3
Brydges, 0. A., Bognor sea-wall, 101

---, questions to be considered in design-
Bude, 330

ing protective works, 3
Budleigh Salterton, 136

Collins, Grenville, charts, 197, 199, 265
Burning Cliff, 157

Colwyn Bay, 168, 316
Burrows. See SAND-DUNES

Combe Martin Bay, 325
Burry Inlet, 321

Compton Bay, 169
Burton Bradstock, 142

Comte Jean, sea-wall, 341
Coode, Sir J., Chesil Bank, 144-148

- , Hove sea-wall, 98
-; - , Spurn Point, 238
Cooding, groynes at, 119

Coolernose Point, 214
CADZAND), 342

Coquet Island, 214
Caermarthen Bay, 321

Cornish, Dr. Vaughan, sand beaches, 151
Caister, 263

- - Chesil Bank, 147
Calais coast, 339

Cornwall, coast of, 330
Calder, river, 302

Corton, 268
Caldy Island, 321

Covehithe, 276
Callanstoog, 346

Cowes, 174
Calshot Castle, 166

Cranz, sea-bank, 114
Cape Antifer, 333, 335

Cressy, T. H., Clacton sea-wall and groynes,
- Barfleur, 333

103, 292
- Blanc Nez, 339

Cromer coast, 251, 28, 249
- Cod, 45

- groynes, 254, 124
- Grisnez, 349

- Point, 218
- La Heve, 335

Crown rights to the shore, 128
Cardigan Bay, 317, 319

Cubitt, Sir W., Rye Harbour, 198
Carnarvon Bay, 317

Culver Cliff, 173
Case, Mr., system of groynes, 124, 125, 203 Curische Haff, 44
Aldborough, 283

Curry Point, 215
Black pool, 310
Borth, 318
Cromer, 256, 257
Deal, 301
Dymchurch, 202

DAUBRÉE, experiments on wear of rock
Eastbourne, 192

fragments, 32
Lowestoft, 273

Deal, coast of, 296
Maria-Kerke, 348

Deben, river, 284
Middel-Kerke, 348

Dee estuary, 314
Mundesley, 260

Deposit of solid matter in water, table
Southwold, 279

sbowing rate of, 65
Weymouth, 156

Dieppe, 336
Worthing, 181

Donna Nook, 238

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