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able to ascertain the cause of the movement at Hedgemead is 

 this — it presents no feature widely dififerent from other landslips 

 — certain beds of clay are super-saturated with water, they 

 become softened at their planes of contact, superincumbent 

 pressure causes them to slide over each other, the upper bed 

 being the one most liable to move. In the ground of the 

 Hydropathic Establishment at Limpley Stoke, they have lately 

 constructed a new tennis lawn, which required that soil should 

 be cut away from the upper side and transferred to the lower; 

 in doing this they cut through two thin beds of clay, the support 

 to these beds being now removed the upper has begun to slide 

 over the lower, bringing the soil down on to the new level. 



What is the remedy for such things ? Clearly the first thing 

 appears to get rid of all superfluous water — and thus to keep the 

 adjacent beds in a condition to exert as much friction on each 

 other as possible — and secondly to reduce the superincumbent 

 pressure. 



As regards Hedgemead, we have had long continued warnings — 

 and if at an unexpected moment some great catastrophe should 

 happen we cannot plead that we have not had notice. Such an 

 event is not probable, but there is no saying what might be the 

 effect of a very wet season and a very stormy time. 



Doubtless there are many other forms that landslips and sub- 

 sidences may take, but these are enough for my present purpose, 

 which had chiefly reference to the Zng disaster. I see a notice 

 from Geneva, in last week's papers, in which it is stated that nearly 

 the whole of the northern shore of the lake of Zug has become 

 unsafe, and that it has been deserted by all the inhabitants. It 

 would be interesting to know how far inland the danger is 

 supposed to extend. The Railway station is not far away and 

 may have to be removed. 



The plans on the table are copies from one issued at Zurich 

 directly after the subsidence, and the photos are copies of 

 photographs of taken on the 6th of July. 



