Rev. T. G. Bonney—On the Roslyn Hill Clay Pit. 405 



hand' extremity is- covered by a talus. Two or three yards to the 

 right is another smaller mass of Gault, apparently disconnected and 

 inclosed in Boulder-clay (possibly re-arranged) . This rests with an 

 irregular base on brown (Neocomian) sand, and the upper part of 

 this sand is full of small flattened nodules of soft clay with car- 

 bonauceous markings and fragments of shells, resembling some of the 

 Weald clays. These soft sands, after about a couple of feet, rest on 

 sandstone and hard conglomerate of small pebbles. The whole 

 appears to dip sharply towards the pit-floor, and I believe has slipped 

 down from above. 



In brief then this section gives us 

 (even if we suppose that the second 

 fragment of Gault became detached Gault. 



from the first during the possible 

 re-arrhngement of the neighbouring 

 Boulder-clay, and that the Gault 

 and Neocomian are dipping in the 

 same direction and conformable, — 

 which I do not believe) a reversed Neocomian, 

 fault of about 45°, bringing the 

 Boulder-clay under the Gault and 



Neocomian : as shown in the an- /Boulder-clay, 



nexed diagram, which is drawn as 

 seen in the cliff. 



Passing along grass-grown talus on the south side of the pit, we 

 find this too much masked to make out clearly the relations of its com- 

 ponent strata. There is much Neocomian rock scattered about, and the 

 wetness of the bank shows that clay is very near the surface. Some 

 of this (at any rate near to where a small mound of white earth may be 

 an evidence of the former presence of Chalk-marl) is probably Gault. 



We then come to a spur projecting from the south side of the 

 pit, where the Chalk-marl is still left ; and discover below it the Upper 

 Greensand seam, with the G^ult in sequence (phosphate nodules and 

 fossils), and beyond this Upper Neocomian resting apparently on 

 Kimmeridge Clay. I have repeatedly examined this section (Fig. 3) ; 

 and from comparison of my notes and drawings have come to the 

 following conclusions : — That the Kimmeridge Clay just at this 

 spot is not horizontal, but dips into the pit at an angle of some 15 

 degrees; that the Upper Neocomian beds which dip at much the same 

 angle are disturbed, shattered, and to some extent mixed with Boulder- 

 clay ; that the Gault is not conformable with the former, but that 

 the plane of junction dips at an angle of not less than 60°, and that 

 the strike is not quite the same ; that the Kimmeridge Clay and 

 Neocomian beds have come into this position by slipping down from 

 above, as the clay in the wall of the pit is horizontally stratified. 

 If however these beds were brought into their present position by 



' If further proof were needed, I found on one oocasion a mass of chalky 

 Boulder-clay, some two feet in diameter, included in the Kimmeridge Clay,, just above 

 the floor of the pit. 



