of the White Chalk. 



It is unimportant to the present question whether this is a case 

 of fault in the ordinary sense, originating in upheaval or depres- 

 sion due to causes acting from below, or whether it is a case of 

 sliding towards the valley. In either case it is equally import- 

 ant that it and all such cases should be noted and known ; 

 though I have little doubt that it is a true fault. I have since 

 met with another case of undoubted true fault — the direction of 

 the fault being transverse to the valley — at a distance of about 

 twenty miles from the last. Of this also an outline is here given, 

 in which a — b will be seen to be the line of fault. Both sides 

 exhibit the upper chalk only, but the fault is well seen owing to 

 the displacement of the layers of flint*. 



Another phenomenon, which is found especially in the middle 

 chalk, is well-worthy of being here noted, — a phenomenon not of 

 fault, but of dislocation. In pits which externally appear smooth 

 and unbroken, and lying underneath thick beds which are wholly 

 undisturbed, the chalk will sometimes be found not to lie in 

 unbroken or merely jointed strata, but to be made up of huge 

 masses, each many tons in weight, and each of the faces of every 

 one of which is smooth and polished f. There is no rubbish : all 

 is massive : but there has clearly been very much dislocation and 

 disturbance, and which must have taken place before the beds 

 lying above were solidified. 



But beyond each of these evidences of motive force in the beds 

 of the white chalk another is sometimes found, which also is 



* Many other instances of faults in the chalk have come under my notice, 

 to which I shall probably take a future opportunity of alluding more in detail. 



f Something of this kind must explain the case cited by Dr. Mantell, 

 ' South Downs,' p. 149, but the " brown " colour is not present in the in- 

 stances I have before me. 



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