BENSTED — ON THE GEOLOGY OE MAIDSTONE. 



449 



process continuing for a very long period of time, as the depth of 

 this clay is, in the highest faults, from eighty feet upwards. The 

 transverse faults were filled also with the same clay, but we now find 

 them occupied by drift-gravel from half an inch to three inches in 

 diameter. Another epoch, I imagine, then occurred, when a force of 

 water swept out the fine clay in the transverse faults, and deposited 

 the drift in its place. This had its subsequent sub;.iidence into the 

 fissure or fault. A. third period then took place, during which the 

 land-surface was reduced to its present form ; some of the faults 

 were hollowed out, others left undisturbed. The undisturbed faults 

 show no indication on the present surface of the subsidence of ma- 

 terials which has taken place within their walls, and this proves that 

 the beds of clay were at one time much higher than they are now. 

 We find a clay similar in many respects to this, lying upon the 

 highest summits of the chalk-hills, and at an elevation of 200 feet 

 above the ragstone on which this lower clay reposes; but this upper 

 clay contains chalk-flints not w^orn by attrition, and immense boulders 

 of "Druid sandstone." I have never found any fragments of rag- 

 stone in these upper beds of clay, which run up to the very verge of 

 the chalk escarpment. At page 301 I have observed that in some 

 situations no indication is seen at the surface of the land of the fault 

 below, although this may be afterwards exposed in digging for stone ; 

 and when a section is thus made, a great subsidence is seen to have 

 taken place, as indicated by bending lines at d d d in the diagram. 



EockyHill, EiverMedway. Thorn Hill. 



Fig. 10,— Section of the beds of Ragstone from E. to W., Maidstone. 



a a represents the beds or cliffs of ragstone. c c, faults filled 

 with red clay, d, divisions of beds of fuller's earth, gravel and sand, 

 clay, etc., showing the lines of subsidence and of lateral pressure of 

 the masses. 



The "Druid sandstone," of which rock Kits Coty house, Stone- 

 henge, and many other Druidical remains are composed, is found 

 scattered in great blocks over the surface of the chalk-hills, or buried 

 superficially in the beds of clay retained in the hollows on the sum- 

 mits of the escarpments. 



These blocks or boulders of siliceous sandstone are composed of 

 granular quartz, and occasionally envelope chalk-flints and other ex- 

 traneous bodies ; they are perfectly analogous to those found in 

 Berkshire and Wiltshire, where tlicy are distinguished by the title of 

 "grey wethers." Dr. Mantell, in his ' Geology of the !South-East 

 of England,' speaks of the " beautiful conglomerate or pudding-stone 

 of Hertfordshire, I have occasionally found fragments of a similar 



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