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sand overlying the lias clay which slopes seaward. After a very rainy season, the. water, soaking through the pervious strata down to the clay bed, caused the sand to be supersaturated. With very little warning, in December, 1839, a portion of the cliff, covering about 22 acres and extending over a length of threequarters of a mile, and for a width of 240 feet, with some cottages, suddenly subsided a depth of 150 feet, leaving a deep chasm 300 feet wide; at the same time the beach was upraised, forming a reef parallel with the shore a mile long and 40 feet high in places. This reef consisted to a considerable extent of the sand and shingle which had covered the beach, and some chert from the cliff. The chalk and gravel which had subsided formed an under-cliff, which, with the exception of the edges of the fallen rocks having lost their sharpness and the surface having become covered with brambles and other vegetation, is very much in the same condition as when the cliff subsided. The mound or reef on the shore, which remained in existence for some years, has now disappeared.1

The beach at the foot of the slip is covered with boulders, but is bare of sand and shingle.

Lyme Regis. Beyond this to Pinney Bay, a distance of 2 miles, the coast is indented with several shallow bays, the beach of which is covered with sand, and some chert and flint shingle; but outside the bays the beach is strewn with large blocks of lias and greensand, which, with ledges of rock projecting from the cliffs, assist in their protection.

From Pinney Bay to Lyme Regis, a distance of 2 miles, the Ware cliffs, which reach to a height of 400 feet, consist of blue lias, limestone, and clay, above which is chalk and greensand. The beach consists of thin beds of lias rock, which, when the British Association Report of 1885 was made, was bare of sand or shingle, and the tides then reached the cliffs at high water.

Large quantities of material have been taken from the cliffs and from the ledges east and west of Lyme Regis for making lime. About 10,000 tons were sent to Hull in one year, to be used in the construction of the docks.

The reefs that were removed acted as a protection to the cliffs, and in the British Association Report of 1888 it was stated that, owing to the denudation of the cliffs, the church was placed in

1 "Memoir of Views of Landslip at Axmouth, on Coast of Devon," by Conybeare and Dawson. London: Murray. 1840.

considerable danger. At the present time there is a deep indent on the east side of the town, and part of the graveyard has gone, the clay cliffs having been eroded to within 25 yards of the church.

There have been several large landslips along the cliffs. Between 1803-33, 90 feet of cliff was lost, partly by weathering, and by the removal of the stone from the base and shore. The loss of cliff has been estimated at 3 feet a year in the soft strata, and 1 foot in the harder rocks.

Material is still removed, but the erection of three stone and one wooden groyne since the report was made has been of service in accumulating some sand and shingle on the beach.

Lyme Regis to Burton Bradstock.-Eastward of Lyme Regis the Church cliffs, consisting of lias limestone, rise to a height of from 70 to 140 feet, and are succeeded by the Black Ridge cliff, rising to 400 feet. This cliff consists of clay and marl, capped by sand and chert gravel. The cliffs then dip down to the valley of the river Char, but rise again to a height of 400 feet at Stonebarrow, and 600 feet at Golden Cap, which consists of marl and clay. Both Stonebarrow and Golden Cap are topped with a thick bed of sand and chert gravel.

The beach cast of Lyme Regis is clay, and bare of sand or shingle.

At Charmouth, and for some distance to the eastward, the beach in the bay is covered with sand, and then shingle commences, the size and quantity of which increase towards Golden Cap, the headland of which, aided by large blocks of stone which have fallen from the cliff, and by ledges of rock on the beach, forms a natural groyne beyond which the shingle cannot travel. On the west side of this headland, below Charmouth, the shingle has accumulated in a bank which extends out from the cliff for a distance of about 30 yards, the pebbles varying fromto 12 inches in diameter. They consist principally of flints and chert, with a few of quartzite and an occasional piece of jasper. Below the shingle to low water is a hard sand beach. This shingle-bank has diverted the small river Char for 300 yards to the east.

West of Charmouth the cliffs have wasted a great deal, one field having decreased 3 acres in 150 years; on the east side within living memory 6 acres of land have been lost, and there was a grass field where now the beach is. The erosion has been less in recent years.

At Seatown, which lies about a mile to the east of Golden Cap, the beach in the centre of the bay, for about 30 yards above highwater line, and from 20 to 30 yards below it, is covered with shingle. This shingle is frequently drifted about, the beach being denuded in south-west gales, and the shingle accumulating again in calm weather or with off-shore winds. The shingle consists principally of brown flints and chert, with a few of limestone and quartzite, also an odd jasper pebble may be found. The majority of pebbles have probably been derived from the gravel beds which have fallen from the top of the cliffs. The pebbles vary in size from to 2 inches, with a few larger.

The sea is gradually gaining on the land here, a road and four houses having gone within the last twenty or thirty years owing to slips of the cliff. A limekiln and road at Stonebarrow have twice been set back, and 7 acres of land been lost about fifty years ago; but the sea only reaches the cliff now at high tides, and there is less waste of land.

Beyond Seatown, Thorncombe Beacon rises to a height of 430 feet. It consists of sand and clay, the upper part having bands of indurated limestone, capped by beds of chert gravel, which afford a supply of shingle to the beach when the cliffs fall. This shingle drifts along the shore in an easterly direction, and accumulates on the west side of the Thorncombe headland, where the projection and some reefs on the beach intercept the travel of the shingle, and a high bank of pebbles, some of large size, is formed on its west side. On the other or east side of the headland there is no proper beach, the sea reaching up to the cliffs at high tides. Such beach as there is consists of small fragments of stone.

From Thorncombe Beacon to the termination of the cliffs at Burton Bradstock, a distance of 3 miles, the coast-line is nearly straight, and there are no indents or bays. The cliffs west of Bridport are clay, sand, and shale, from 40 to 100 feet in height; and between Bridport and Burton, sand with indurated bands of sandy limestone, which is easily acted on by the weather and sea.

At Eypemouth there was a considerable landslip in 1897, when a mass of cliff about 50 yards in width fell, and further falls have taken place since. It is estimated that these cliffs are wasting at the rate of 1 to 3 feet a year.

The beach between the headlands is covered with sand, and in the bight of the bay there is a fair sprinkling of shingle, which

extends out from the cliffs in the centre for 50 yards at an inclination of 1 in 10. There are also a few lias stone boulders projecting from the beach. The pebbles are irregular in size, varying from to 24 inches in diameter. They consist principally of flint, chert, and lias limestone, with a few quartzite, some of which have marks like blood-spots similar to those found at Budleigh Salterton. The flint and chert shingle appears to have been derived from the inland gravel beds on the top of the cliffs.

West of Bridport Harbour the cliffs consist of sand and lias clay capped with gravel. They are continually falling. Recently a mass of clay cliff 20 yards wide fell on to the beach. The beach, for a distance of about 15 yards from the cliff above the line of ordinary high water, and for 35 yards below it, is covered with shingle varying from to 1 inch in diameter, beyond which is lias stone. The shingle has accumulated nearly to the top of the esplanade wall, in the pocket formed by this and the west pier of the harbour. A considerable sea breaks on this shore, and it is recorded that in a gale about four years ago two fishing-smacks were lifted bodily by the waves and deposited on the promenade.

East of Bridport Harbour the beach is of a different character to any other along this coast, and resembles that at Slapton in the size and shape of the pebbles, but the material of which they are composed is different. Abutting up to the eastern wall of the harbour, and between there and the cliffs which commence about 300 yards to the eastward, the shingle has accumulated in a bank stretching inland above high water for about 50 yards, and beyond this for another 130 to 200 yards. In front of the cliff's from here to Burton Bradstock, the width of the shingle is from 60 to 70 yards wide. This shingle consists principally of flint and chert; there are a few limestone pebbles and some pink quartzite, and a peculiar red flint similar to those found on the Chesil Bank. The bulk of the pebbles vary from to inch in diameter.

At Burton Bradstock, 23 miles further east, the character of the shingle is the same as that to the east of Bridport, but there are several large pebbles up to 12 inches long interspersed amongst the small ones.

Shingle and sand are removed from the beach near Bridport for ballast for vessels, and for railway ballasting and roads.

The cliffs between Bridport and Burton Bradstock range from 120 to 140 feet in height, and consist of sand with indurated

bands of limestone belonging to the Oolite series and beyond the river Brid, of clay and marl with a band of limestone.

These cliffs end about a mile beyond Burton Bradstock, where the Chesil Bank commences.

Behind the shingle-bank and the Fleet the coast consists, from Burton to Chesil, of various strata, including fuller's earth, cornbrash, Oxford clay, and coral rag, and near Wyke, Kimmeridge clay. Inland there are some gravel beds.

The Chesil Bank.-The Chesil Bank, situated at the east end of Lyme Bay, is one of the most remarkable collections of shingle to be found in this country. The name is derived from A.S. cesil, a pebble."

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The bank, commencing near Abbotsbury, extends thence in a south-easterly direction to the Island of Portland, which it joins at Chesilton, the distance being 103 miles; westward of Abbotsbury the shingle slopes down from the low cliffs as in the case of an ordinary beach, and gradually dies out at Bridport Harbour, a distance of 4 miles. At the Portland end the shingle-bank sweeps round in a southerly direction nearly to Blacknore Point.1

Between the bank and the shore is a sheet of tidal water known as the Fleet, varying in width from a quarter to half a mile. This backwater is entirely cut off from the west or Lyme bay, but is in communication with the east bay. It receives the discharge from some small streams, which have been diverted from the west bay by the shingle-bank.

The east end of the bank acts as a natural breakwater to Portland Roads in the east bay, sheltering it completely from south-west gales.

The average width of the base of this mound, as given by Sir J. Coode, varies from 600 feet at the east end to 500 feet at the west end. The height at the Portland end above L.W.S.T. is 53 feet, and at Abbotsbury 32 feet. The top is 43 feet and 23 feet respectively above H.W.O.S.T.

1 66 Description of the Chesil Bank," by John Coode. Min. Proc. Inst. C.E., vol. xii., 1853.

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The Origin of the Chesil Bank," by Joseph Prestwich. Idem., vol. xl., 1875. "The Alluvial Formation of the South Coast of England," by J. B. Redman. Idem., vol. xi., 1852.

"The Chesil Bank, Dorset, and Raised Beach at Portland," H. W. Burton and William Whitaker. Geolog. Mag., Oct. 1869.

"The Grading of the Chesil Beach Shingle," by Vaughan Cornish. Proc. Dorset Natural History Field Club, 1898.

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