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earthquake some years ago precipitated masses of overhanging rock into several 

 vaUeys. GeneraUy they are caused by the effect of springs of water accumulating 

 on retentive beds of clay acting on cracks, undermining the strata, and saturatmg 

 beds with moisture, untU a track of land is undermined and is precipitated mto 

 the valley below. 



The geological formation of the ground has much to do with the kind of 

 landsUp. The landsUps of Lyme Regis, on the Une of coast between Lyme and 

 Axmouth, is an example of such dislocations along a long line of coast, as is also 

 the UndercUff of the Isle of Wight. The Lyme landsUp happened in 1840, 

 but even now it presents a v\ild scene of ruin, exhibiting fragments of once 

 cultivated fields amid chalky knolls, and crags, and broken dingles. The strata 

 of both the Lyme Regis landsUp and that of the Undercliff, in the Isle of Wight, 

 are much more horizontal than are those on the slopes round the VaUey of Wool- 

 hope— whether you examine that of Backbury Camp, above Dormington (Adam's 

 Rocks), that above Pirton, near Stoke Edith, or that of the Wonder, near Marcle. 

 All the Woolhope landsUps occur on the line of junction between the harder Ume- 

 stonesof the Aj-mestry rocks and the softer Ludlow shales, while you may observe 

 that the angle at which the beds dip teU of their high inclination from the axis of 

 upheaval. LandsUps often occur on Unes of joints as well as on Unes of high dip. 

 Indeed, wherever we find rocks traversed by joints, or upheaved at a high angle, 

 or interstratified with beds of a porous nature and sloping, landsUps from time to 

 time are sure to happen. 



" The Wonder " is somewhat classical in its associations, as it is recorded in 

 Drayton's " Polyolbion," and is thus described by Camden :— " Near the conflux 

 of the Lugg and Wye, eastward, a hill, which they caU Mardey HiU, in the year 

 1575 roused itself up, as it were, out of sleep, and for three days together shoving 

 its prodigious body forwards, with a horrible roaring noise, and over-turning all 

 that scood in its way, advanced itself (to the astonishment of beholders) to a 

 higher station by that kind of earthquake, I suppose, which the naturaUsts caU 

 Brasmatia." In 1783 there happened the landsUp on the Severn near Buildwas 

 Abbey and Leighton. Here a large mass of earth and wood was precipitated into 

 the Severn, and we find the visitors to the scene of disaster "picking up eels and 

 fishes on dry ground," looking for " curious fossils," a great many of which bore 

 " the impression of a flying insect not unUke a butterfly into which silkworms are 

 changed." I need not say these " flying insects " were the taUs of trilobites, and 

 that if the fallen debris of " The Wonder " had been examined at the time plenty 

 of Butterflies would have been found there, as I found at the great sUp between 

 Dormington and Stoke Edith which I visited soon after it happened with Sir C. 

 LyeU, who there observed and was much interested in the Pentamerus galeatus, 

 which is also abundant at Niagara. Our EngUsh landsUps, however, are nothing 

 compared to those which have happened on the Continent, as that of Chiavenna, 

 in Switzerland, where in 1618, the town of Pleurs, with upwards of 2,000 of its 

 inhabitants, were buried underneath a landsUp from the side of Monte Conto ; or 



