, we Behe lk 
254 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [| Feb. 23, 
Sandy schistose stone. 
Yellow sands, 
Yellow clayey sand. 
To the north-west of this quarry and at a little distance we find 
the strata dipping south and east, while on the south of this and of A. 
quarry, and rather near them, with a little depression of the surface-— 
line intervening, we find a small quarry (B.), Fig. 2, im the same 
Purbeck formation, dipping in an opposite direction,—to the north, 
with some of its strata nearly vertical. 
I cannot therefore but suspect that the gradual dip to the north of 
B. quarry increasing towards verticality pomts to the complete doule- 
versement of the Purbeck formation in A. quarry, and that the yellow 
sands and yellow clay are really a part of the Hastigs sands*. If 
this be a correct view of the subject, we may have found the same 
cause acting here also which produced the conditions of the strata in 
the Ridgway cutting. 
The local geological features of this district having been considered, 
it will now be desirable to take a more comprehensive view of the 
great chalk range in its comparatively undisturbed state ; and it gives 
me pleasure to acknowledge that the importance of directing attention 
to the range generally was suggested to me by Mr. Lonsdale, our late 
and much-valued Curator. 
If we consult Conybeare and Phillips, we find from about south of 
Wincanton, the high escarpment which continues its course to the 
south part of Dorset is generally composed of—1. chalk ; 2. green- 
sand; and 3. Oxford clay. It is stated} that “from Melksham 
(Wilts) the Oxford clay contimues its course through Somerset and 
Dorset, passing by Wincanton and Sturminster, on the south of 
which it is overlaid by the great western extension of the chalk and 
greensand ;” and although the coral rag is visible south of Melksham, 
yet “near Wincanton the greensand (overlying the basset edges of 
the coral rag) advances upon the Oxford clay.” 
Mr. Greenough in his Geological Map seems to be of the same 
opinion to a still greater extent, as the whole range (with one excep- 
tion) from Frome to Ridgway is made to consist of these three several 
formations. 
If we consult the surface-map of the authors of the paper above 
referred to, we find several localities exhibiting the same order within 
a short distance of the spot under consideration. 
We may therefore on the whole consider the geological superposi- 
tion of this great range as consisting generally of chalk, greensand 
and Oxford clay ; and thus the Oxford clay will m effect be brought 
high up in the geological series. 
The Oxford clay at Weymouth and the Oxford clay at Ridgway 
* This idea, in connection with the positive existence of this formation in the 
Ridgway Hill cutting, leads me to conjecture that the Hastings sands really range 
much further west. They may be co-extensive with the Portland oolite, and thus 
reach nearly to Portisham. Perhaps too the Purbeck deposit may ultimately be 
found equally extensive. 
t+ Conybeare and Phillips, 198. 
8 
