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PEOCEEDINGS OP THE GEOLOGICAL SOCIETY. [Jime]^20, 



At "Wangford tile Crag is at the surface continuously for about a 

 furlong, at the bottom of a hill, and comes out with the red sands over 

 it immediately above some marsh-ground. On the opposite side of 

 the valley, divided from the Crag by this marsh, a Chillesford-Clay- 

 pit occurs, on the top of the hill, distant about half a mile, occupying 

 precisely the same position relatively to the Crag-pit as does the 

 Chillesford- Clay-pit at Thorpe to the Crag-pit there (see fig. 2). 

 Were it not for the interception of the view by a row of high trees, a 



Fig. 2. — Section showing the position of the Bulchamp and Wangford 

 Crag-pits relatively to the Chillesford Clay (2 miles). 



a. Boulder-clay. 



b. Chillesford Clay. 



e. Eed sands between 



riuviomarine 



Crag and the Chillesford 

 (d3' and 4' of Diagram). 

 d. Fluviomarine Crag. 



Clay 



spectator standing on the edge of the Clay-pit here would look down 

 into the Crag-pit some 20 to 25 feet below him, in the same manner 

 as is the case at Thorpe. Nothing but an actual vertical section 

 (which would require to be 30 feet at least in height) could, I think, 

 show more clearly the superiority, in these places, of the Chillesford 

 Clay to the Fluviomarine Crag than do these two sections. With re- 

 spect to the passage upwards of both the Fluviomarine and Eed Crags 

 into the Chillesford beds, it is only necessary to observe that there 

 is nothing to indicate any break either physically or palaeontologically. 

 In the case of the Fluviomarine Crag the interval is represented by 

 a mass of red sand, of which abundant sections occur around Wang- 

 ford and Bulchamp, and which, as I have said, is in section at the 

 My til US-pit of Mr. Fisher at Thorpe, and in the adjacent railway- 

 cutting. The sand containing the shell-bed, which passes evenly 

 into the Chillesford Clay, and shells of which occur in the base of the 

 clay itself in the Cliff at Easton, is, I have no doubt, only the upper por- 

 tion of these sands ; but no sufficient section seems to exist to show 

 the passage. In the case of the Red Crag this interval of sand is, 

 as my son pointed out to me, occupied by the upper or horizontal 

 portion of the Red Crag, exposed in the pit below the church at 

 Chillesford — that to which I have further on to refer as the Scrobi- 

 cularia-crag ; but neither of us could form a positive opinion whether 

 or not this Crag had been laid dry in the interval between its 

 deposit and the overspread of the sand containing the Chillesford 

 shell-bed (Mya-bed of Fisher). Pot-holes descend into it, but it is 

 not altogether clear whether these are of the age of the sand, or of 

 post-glacial origin ; the even bedding of the sand over them seems, 

 however, to point to the former. Be this as it may, I do not regard 



