194 Dr. FiTTON on the Strata below the Chalk. 



Paces. 



2700. The King's Head Inn, at Sandown, by Sir John Herschel's measurement, is 2700 paces 

 from the gap or fissure at Little-stairs point. 



The coast, from the end of the cliff above mentioned, to a point about 400 paces north of the 

 Fort, is a dead flat, occupied by the Weald-clay, which is visible at low tides on the shore 

 beneath the Inn, and thence southward. 



At 364 paces north of the Inn, beds of ferruginous (Hastings) sand first make their appearance, 

 rising from beneath the clay, which dips to the south-west at an angle of about 5° : this being 

 the descending side (on the south-west) of the curve, of which the summit is at 3330 of the pre- 

 ceding list, (97.). 



(100.) Strata on the South-west Coast of the Isle of Wight, from 

 Blackgano Chine to Brook Chine. 



At the west end of the back of the island, the Lower green-sand makes its 

 appearance beneath the Gault^ a little to the east of Puckaster Cove^ where 

 the sands are ferruginous. 1 have no sections from that point to Black- 

 gang Chine^ a space much obscured by ruins fallen from above : but thence 

 westward, the sections, from about the middle of the Lower green-sand to 

 the lowest beds of the Hastings series which appear above the sea, are probably 

 the most complete and the best developed that anywhere exist in England. In 

 the following list, the numbers, as far as Cowleaze Chine, are taken from Sir 

 John Herschel's sections, and the descriptions from his notes, with additions 

 from my own. 



A. Blackgang to Cowleaze Chine. 



In the broken ground above Blackgang Chine, whitish sand-rock is visible immediately beneath 

 the Gault, above the Sand- rock spring*, which breaks out about 150 feet above the sea, and ap- 

 parently about 50 feet below the top of the green-sand, from whitish sand, containing much lignite 

 in small fragments, with a considerable depth beneath of dark and ferruginous sands mixed with 

 clay. There can be little doubt that these upper beds which form the shore between Puckaster 

 Cove and Blackgang Chine, belong to the uppermost group of this formation. (See above (16.) et 

 seq.) The same beds form also the heights about the village of Chale, and seem to extend from 

 that place from Walpen to Kingston, as already, mentioned, (93.) p. 184. 



The strata immediately over Blackgang Chine, rise upon the shore at a considerable distance to 

 the east t. They consist of the following substances : 



* A full account of this spring, by the late Dr. Marcet, has been published in a former volume 

 of these Transactions, (1st Series, Vol. I. p. 213, &c.). It is remarkable for the extraordinary 

 quantity of saline matter which the water holds in solution; — no less than 107 grains in 16 ounces; 

 of which 41*4 are sulphate of iron; 31 "6 sulphate of alumina. The saline matter in one of the 

 strongest mineral waters previously known, at Horley Green, near Halifax in Yorkshire, is only 

 40 grains in the same quantity of water. The water of the streamlet at Blackgang Chine itself is 

 pretty strongly impregnated with sulphate of iron. 



t The gravel on the beach along this part of the coast consists, in a great measure, of small 

 rounded fragments of chalk flint ; which, from their incessant agitation under the surge, are 

 worn, and almost polished, to such smoothness and mobility, as to render it extremely laborious 

 to walk there. 



