March i6, 1893] 



NATURE 



469 



to be bulged up, so as to form a mound on the foreshore, 

 which is being rapidly destroyed by the sea ; while fur- 

 ther east, opposite the end of WelHngton Terrace, the 

 overlying more sandy clays are also seen bulged up. 

 Along the main road also, in front of West Lawn, on the 

 western side of the supposed fault, the surface has been 

 squeezed up. On the eastern side of this fault, further 

 cracks, indicating a forward motion, are seen at the 

 entrance to Encombe grounds ; and, finally, the Coast 

 Guard houses and the wall in front bulge forward at least 

 three feet, and probably more, and the two sides of the 

 street opposite have been squeezed together. 



Thus the whole disturbance has been caused by the 

 slipping downwards of the overlying soft beds over the 

 inclined plane formed by the basement band of clay 

 which rests on the Hythe Hmestone as a firm foundation, 

 the direction of motion having been somewhat modified 

 by the resisting mass of rock which lies to the east, and 

 by the natural tendency of the sliding mass to take the 

 shortest course to a lower level. 



It is thus seen that the circumstances of the locality 

 exactly fulfil the usual geological conditions for a 

 landslip — i.e. a sloping bed of clay, which is liable to 

 become slippery, and whose dip is towards the lower 

 surface level where the overlying rocks find no support. 

 Hence it may safely be said that any geologist, whose 

 attention had been specially directed to the question, 

 could have predicted that such an occurrence was ex- 

 tremely likely, sooner or later, to happen. There is, 

 however, one necessary condition, which does not depend 

 on the lie of the strata and the form of the ground, and 

 that is that the clay should become slippery. This con- 

 dition will probably, account for the fact that in the area 

 to the east of the Enbrook fault where all the other con- 

 ditions are satisfied, i.e. in the neighbourhood of Radnor 

 Cliff, no landslip has occurred. Clay is of course 

 rendered slippery by the access of water. Now water 

 will easily find its way through sandy strata, and there 

 are sandy beds even in the lower portion till we come to 

 the band of clay itself. As this is equally true in both 

 localities the only difference can be in the amount of 

 water. 



Now there is a natural tendency for water to run down 

 the dip slope of the strata, especially when there are 

 hard bands as in the Folkestone beds, so that in this 

 case most of the water will come from the west, and this 

 source is cut off from the Radnor Cliff side by the 

 Enbrook Valley, to the east of which there is little or no 

 gathering ground ; but to the west and north-west of the 

 disturbed area there is a wide expanse of high ground, 

 mostly rising loo feet above the level of the Sandgate beds, 

 and the water which falls on this finds its easiest outlet 

 into these beds. They are therefore exactly in a position 

 to get waterlogged, and that they are so is shown by the 

 numerous springs that may be seen along the upper 

 limit of the disturbed area. 



The above considerations show that this area always 

 has been and always will be liable to landslips. The lie 

 of the beds which produces this liability cannot be 

 altered by human agency, but the liability may be reduced 

 to a minimum by a suitable system of drainage, which 

 shall prevent the access of so large a body of water to so 

 dangerous an area. 



In the meantime the inhabitants of Sandgate may con- 

 gratulate themselves that the shoreward dip of the beds 

 and fault which breaks their continuity have reduced the 

 result of the slip to a minimum, and rendered possible the 

 remarkable circumstance that, though it happened in an 

 area covered with houses, not a single house has been 

 actually thrown down — not a single life lost. 



As to the immediate cause of the occurrence, it is per- 

 haps scarcely necessary to look for it. The landslip must 

 necessarily have occurred at some time or another, and 

 the conditions must for a long time have been gradually 



NO. 1220, VOL. 47] 



accumulating, by the constant access of water and the 

 wearing action of the sea. If, however, the free discharge 

 of the water from the beds has been in any way inter- 

 fered with— by the stoppage of wells, or the construction 

 of imperforate sea-walls— this would doubtless tend to 

 the acceleration of the catastrophe ; and an exceptionally 

 wet season, like that we have recently experienced, might 

 suffice to determine it. It would be scarcely necessary 

 to add, except that the idea has been mentioned in the 

 House, that the blowing up of the Benvenue and the Calypso 

 could have absolutely nothing to do with it : in the first 

 place, because the scene of the explosions was to the 

 west of the disturbed area, and cut off from it by the 

 massive Hythe beds, which are absolutely undisturbed— 

 to say nothing of the Atherfield clay at sea which must 

 necessarily intervene ; secondly, because such a cause 

 could not require several months to operate ; and, 

 lastly, because a vibration would rather tend to cause such 

 beds to settle than to slip. J. F. Blake. 



NOTES. 



Prof. Virchow will deliver the Croonian Lecture this after- 

 noon, and in the evening he will be entertained at the public 

 dinner which is to be given in his honour at the Hutel Metro- 

 pole. It may at the same time be noted that an important 

 scientific work, in three volumes, has just been issued by the 

 Berlin publisher, August Hirschwald, in memory of the celebra- 

 tion of Prof. Virchow's seventieth birthday. The work is 

 entitled "Internationale Beitrage zur Wissenschaftlichen 

 Medicin," and among the contributors to it are Sir James Paget, 

 Sir Joseph Lister, and other English writers. 



A MOVEMENT has been started for the celebration of the 

 hundredth anniversary of the birth of the illustrious Russian 

 mathematician, Lobatcheffsky, who was described by the late 

 Prof. Clifford as "the Copernicus of geometry." He was born 

 on October lo, 1793. It is proposed that honour shall be done 

 to his memory at the Imperial University of Kasan, with which 

 he was for many years connected as a professor and as rector. 

 The Physico-Mathematical Society of the University, which has 

 taken the matter in hand, hopes to be able either to establish a 

 prize with Lobatcheffsky's name for researches in mathematics, 

 or to erect a bust of the great investigator in the University 

 buildings. If the funds suffice, both of these things will be done. 

 Subscriptions should be sent to the Physico-Mathematical 

 Society, Kasan. 



The German Congress of Naturalists and Physicians, which 

 was postponed last year on account of the outbreak of cholera, 

 is to meet this year at Niirnberg. 



Prof. W. C. Roberts-Austen, F.R.S., chemist and assayer 

 to the Royal Mint, and Mr. Thomas Bryant, President of the 

 Royal College of Surgeons, have been elected members of the 

 Athenasum Club, under the provisions of the rule by which the 

 Committee is empowered to elect annually nine persons "of 

 distinguished eminence in science, literature, the arts, or for 

 public services." 



The half-yearly general meeting of the Scottish Meteoro- 

 logical Society was held at Edinburgh on Monday, March 13. 

 The council of the society submitted its report, and the follow- 

 ing papers were read : — On the temperatures of Lochs Lochy 

 and Ness as affected by the wind, by Dr. Murray ; mean tem- 

 perature of London from 1763 to 1892, by Dr. Buchan ; 

 hygrometric researches at the Ben Nevis Observatories, by 

 A. J. Herbertson. 



We understand that an enormous iron meteorite weighing 

 nearly one ton (2044 lbs.) has just been received by Mr. J. R. 



