122 



GEOLOGY OF THE ISLE OP WIGHT. 



Fig. 33. Fig. 34. 



Calyptrcea trochiformis, Typhis pungens, 

 Lam. Brand. 



Fig. 35. 



Pecten reconditus, 



Brand. 



Headon Hill Sands. 



Between the Barton Clay and the Headon Beds lies a mass 

 of unfossiliferous or sparingly fossiliferous sands. These have 

 been usually called Upper Bagshot Beds, but as they probably 

 belong, as already mentioned, to a higher zone than the Upper 

 Bagshot Series of the London basin, it is better to use for the 

 present the older term " Headon Hill Sands." 



The lower part of these strata at Headon Hill consists of about 

 50 feet of yellow and white sand, succeeded by 60 feet of white 

 sand, with occasional yellow stains caused by the presence of oxide 

 of iron. The total thickness of this group in Alum Bay cannot 

 be determined accurately, in consequence of the disturbed state of 

 the beds there, but probably it ranges from 140 to 200 feet. The 

 Headon Hill Sands art of considerable economic value, their 

 whiteness and purity rendering them particularly suitable for 

 making glass, for which purpose they were extensively worked 

 for many years. Mr. Squire, who rented the cliffs for several 

 years, stated that between 1850 and 1855, 21,984 tons were 

 shipped from Yarmouth, principally to Bristol and London, 

 for the use of the glass-houses there ; and a native author, 

 writing in 1795, says, — "Our trade and commerce chietiy 

 is dealing in corn and wool. There are other commodities, such 

 as copperas stones and white shining sand. The former are 

 gathered up in heaps on the sea-shore, and occasionally sent to 

 London, &c. for the purpose of producing the several species of 

 vitriol ; the latter is dug out of some very valuable mines, which 

 are the property of David Urry, Esq., near Yarmouth, and 

 from thence sent to London and Bristol for the use of the glass 

 manufactories." 



Inland there are at present few or no clear sections of these 

 Sands, but pits, now overgrown, formerly showed the junction with 

 the overlying clays of the Fluvio-marine beds. This junction was 

 formerly seen in a ])it about half a mile west of Swainstone, by 

 the bide of a road t<> Fulholding Farm; and, again, further east, 

 under similar circumstances, in the lane a short distance south of 

 Great Park Farm. 



