part 4] JUEASSic cheois'Ologt. 428 



To account for these facts and inferences, the following history 

 of events may be suggested. Diagram 11 (I-Y), pp. 424-25, 

 which illustrates the different events is merely a slvetch, only 

 approximately to scale. Vertical scales are, of course, greatly 

 exaggerated in relation to horizontal: — 



(i) Towards the end of the deposition of the Red Bed there was elevation 

 of the tract of Bridport Sands on the east. 



(ii) There was denudation of this tract, and then the White Bed was 

 deposited on a surface consisting of Red Bed in the west, passing across strata 

 down to Bridport Sands in the east (I in diagram 11). 



(iii) Subsequent to the deposition of the White Bed, and before the deposi- 

 tion of the Astarte Bed, there was a renewed elevation of the Bridport Sands. 

 Then there was denudation of the White Bed and its complete removal oft" 

 the Red Bed, but its preservation in the Bridport-Sand area in a small fold 

 east of the anticlinal axis (II in diagram 11). 



(iv) Following this was the deposition of the Astarte to zigzag strata non- 

 sequentially upon the various denuded surfaces (II). 



(v) Renewed elevation of the Bridport-Sand tract came next, with a denu- 

 dation which removed from that tract all the zigzag to Astarte-'Bed strata 

 and possibly some more of the White Bed ; because the supposition that the 

 later denudation should cease at the same place as the earlier makes too much 

 demand upon coincidence (III in diagram 11). 



(vi) On such a denuded area Fuller's Earth was deposited (III). 



(vii)^ At some date subsequent to the deposition of the Fuller's Earth — 

 perhaps at the same date as the faulting in Watton Clift' — the strata of the 

 Bridport-Sand tract bearing the White Bed were let down considerably, and 

 at as steep an angle as are the Junction-Bed and Fuller's Earth of the faults 

 in Watton Cliff. 



(viii) That the soft Fuller's Earth would be rapidly removed, and would 

 then leave the White Bed exposed. IV (diagram 11) gives a view of this 

 condition of affairs, in profile at right angles to the supposed fault-face, the 

 elevation of the rocks inland being of course greatly exaggerated in relation 

 to the horizontal scale, and V gives a picture of the same looking on to the 

 fault-face, omitting the rocks which lie directly inland, but showing those of 

 the cliff which lie to the westward. In this case it should be noted that 

 really, from the fault westwards along the cliff to where the Fuller's Earth is 

 l^reserved, is a distance of about half a mile. 



(ix) While the White Bed was being eroded from the surface of the Red 

 Bed, there is the possibility that portions of it may have been broken off and 

 cemented on to the top of the Red Bed with ground-up paste of the Red Bed ; 

 and there is always the possibility that pockets of the White Bed may yet be 

 found in hollows of the Red Bed. A recent discovery of a possible White- 

 Bed block in the Astarte Bed will be noticed presently. 



This theory of the course of events is, at any rate, superior to the 

 percolation theory, in that it does not commence with an incorrect 

 assumption as to the facts. The only real call that it makes on 

 probability is in postulating two elevations and erosions, the second 

 elevation being so adjusted that all the hard rocks of Garanfiana 

 to zigzag hemerae are removed froiTi the surface of the White 

 Bed, but that some portion of the White Bed is left intact. Yet 

 this is only asking for a phenomenon on a small scale, such as is 

 exhibited on a large scale over a considerable area of the Cottes- 

 wolds. There the strata which intervene between those of hrad- 

 fordensls aiid Garanfiana hemene were deposited after a period of 



