598 



DENUDATION AND SCENERY, 



and they have occurred in great magnitude along the coast at different periods. A 

 landslip occurred at Beer Head in 1790. The great landslip of Dowlands and 

 Bindon, near Lyme Regis, took place at Christmas, 1S39 (see Fig. 99) ; the length 

 of the great chasm caused by this founder was 1000 yards, the breadth 300 yards, 

 and the depth varied from 130 feet to 210 feet, while twenty-two acres of land 

 were sunk in the chasm.' (See also Fig. 40, p. 252.) Landslips have occurred on 

 Portland in 1665, 1734, 1750, and 1792, and also at St. Albans Head ; these have 

 been promoted by joints and fissures in the rocks. Landslips have taken place 

 inland at Hermitage, in the Vale of Blackmore, in 1583 ; and near Selborne 

 in Hampshire in 1764. 



In the Isle of Wight the beautiful scenery of the Undercliff between Blackgang 

 chine and Bonchurch near Ventnor, has been produced by the Chalk and Greensand 

 foundering over the Gault Clay, which for this reason has been called ' the blue 

 slipper.' There is an Undercliff of old date, known as the Warren, at East Wear 

 Bay, near Folkestone, and a landslip occurred hereabouts in 1716. Landslips 

 have also taken place near Beachy Head, and to the east of Hastings.^ 



Fig. 99. 

 Bindon Cliff. 



-DiAGR.\M Section of Landslip near Lyme Regis. 



Sea-level. 



a. Chalk. ^- s^^ds^^'^^' | Upper Greensand. ,/. Lias and Rh.-etic Beds. 



The overthrow in 1275 of the nave of the church on Glastonbury Tor has been 

 attributed to an earthquake ; but as the tower was not affected, it may be that the 

 foundations of the church were partially undermined by springs carrying away 

 portions of the Oolitic sands on which the church was built. 



In the neighbourhood of Bath and along the Cotteswold Hills' vast masses 

 of the Great Oolite are frequently spread over the slopes of the Fuller's Earth, and 

 the Inferior Oolite is similarly tumbled in places over the Lias. 



Large landslips have taken place in the Upper Ludlow rocks of Marcley Hill, 

 Herefordshire, in 1575, and near Ludlow (see p. loi) ; in the Woolhope district, 

 the Upper Ludlow rocks, uwing to their jointed nature and steepness of dip, have 

 frequently tumbled into the valleys. 



East of Build was Bridge, near Coalbrookdale, a landslip occurred in 1783, in 

 the W^enlock Limestone. Many landslips have occurred in Derbyshire, at Mam 

 Tor (see p. 167), and around the Peak district, where the Kinder Scout Grit 

 is underlaid by shales.* 



Landslips have occurred along the coast between Flamborough Head and Filey 

 Point, where the Chalk and Speeton Clay are exposed ; many have taken place 



^ A model of this landslip by Mr. W. Dawson may be seen at the Museum in 

 Jermyn Street, London. Fig. 99 is partly taken from a drawing by Mr. Dawson, 

 see Conybeare and Dawson, o/>. cit. ; and George Roberts, Account of the Mighty 

 Land-slip of Dowlands and Bindon, ed. 5, 1839. 



- Weaver, T. G. S. ii. 192. 



^ G. F. Playne, Proc. Cotteswold Club, 1S68, p. 230 ; E. Witchell, Ibid. p. 223. 



* E. Hull and A. H. Green, Q. J. xx. 253. 



